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Applying Climate Compatible Development and Economic Valuation to Coastal Management: A Case Study of Kenya's Mangrove Forests
Abstract
Mangrove forests are under global pressure. Habitat destruction and degradation persist despite longstanding recognition of the important ecological functions of mangroves. Hence new approaches are needed to help stakeholders and policy-makers achieve sound management that is informed by the best science. Here we explore how the new policy concept of Climate Compatible Development (CCD) can be applied to achieve better outcomes. We use economic valuation approaches to combine socio-economic data, projections of forest cover based on quantitative risk mapping and storyline scenario building exercises to articulate the economic consequences of plausible alternative future scenarios for the mangrove forests of the South Kenya coast, as a case study of relevance to many other areas. Using data from 645 household surveys, 10 focus groups and 74 interviews conducted across four mangrove sites, and combining these with information on fish catches taken at three landing sites, a mangrove carbon trading project and published data allowed us to make a thorough (although still partial) economic valuation of the forests. This gave a current value of the South Coast mangroves of USD 6.5 million, or USD 1166 ha(-1), with 59% of this value on average derived from regulating services. Quantitative risk mapping, projecting recent trends over the next twenty years, suggests a 43% loss of forest cover over that time with 100% loss at the most vulnerable sites. Much of the forest lost between 1992 and 2012 has not been replaced by high value alternative land uses hence restoration of these areas is feasible and may not involve large opportunity costs. We invited thirty eight stakeholders to develop plausible storyline scenarios reflecting Business as Usual (BAU) and CCD - which emphasises sustainable forest conservation and management - in twenty years time, drawing on local and regional expert knowledge of relevant policy, social trends and cultures. Combining these scenarios with the quantitative projections and economic baseline allowed the modelling of likely value added and costs avoided under the CCD scenario. This suggests a net present value of more than US$20 million of adoption of CCD rather than BAU. This work adds to the economic evidence for mangrove conservation and helps to underline the importance of new real and emerging markets, such as for REDD + projects, in making this case for carbon-rich coastal habitats. It demonstrates a policy tool - CCD - that can be used to engage stakeholders and help to co-ordinate policy across different sectors towards mangrove conservation.
Copyright © 2015 Elsevier Ltd. All rights reserved.
... Our method for transforming fish biomass into monetary value was straightforward but has been demonstrated to be highly useful and effective for estimating the value of fishing resources in various coastal habitats, including seagrass beds and coral reefs (Polunin and Roberts 1993;Watson, Coles, and Long 1993;Harborne et al. 2008;Unsworth et al. 2010). Overall, our estimates of potential monetary value of fishery resources in surf zones of the Gulf of Cádiz (408.63 €/ha*year) differed from other authors (coastal vegetated ecosystems in Australia, 61,150 Australian dollars (AUD)/ha*year, Jänes et al. 2020; fisheries in Kenyan mangroves, 229 US dollars (USD)/ha*year, Huxham et al. 2015). A higher value of resources in surf zones of the Gulf of Cádiz may be related to the extensive coastline that spans 280 km in Spain (Del Río et al. 2012), and large continental shelf with high nutrient inputs from major rivers (e.g., Guadalquivir, Guadiana, Tinto, Odiel) (García Lafuente and Ruiz 2007). ...
... The higher value of juvenile benthic species than for adults in our study was similar to seagrass meadows in the Canary Islands, where juveniles were two orders of magnitude higher in value than adults . In other similar habitats, juvenile fish are more productive and therefore have a higher PMV than adults, as in seagrass meadows, mangroves or marshes (Kamimura, Kasai, and Shoji 2011;Huxham et al. 2015;Cole and Moksnes 2016;Jänes et al. 2020). This difference in our results between juveniles and adults could be related to high productivity of the Gulf of Cádiz (Navarro and Ruiz 2006) which provides environmental conditions favourable to recruitment, such as salinity flows, turbidity and food availability (Miró et al. 2020). ...
... In conclusion, our estimates of monetary value can serve as an initial step in recognising the present and future ecosystem value of sandy beach surf zones, as in other vital coastal habitats like mangroves or seagrass meadows (Bertelli and Unsworth 2014;Huxham et al. 2015). Future research is also needed to understand ecosystem functions in global surf zones, with the most urgent need being to examine how the communities inhabiting these areas interact with urbanisation, beach use and ecological relationships (Olds et al. 2018), as these areas, much like seagrass meadows (Costanza et al. 1997), offer diverse values beyond fishery resources, including temperature regulation and sediment transport processes (Defeo et al. 2009). ...
Beaches are among the world's most important coastal ecosystems, within which surf zones are crucial providers of essential ecosystem services to humans. We completed the first estimate of current and potential monetary value of fishery resources in surf zones of beaches on the southwestern Iberian Peninsula. Over 1 year, five beaches in the Gulf of Cádiz were sampled using a beach seine. For monetary valuation, average first‐sale prices were used, with a capital update based on the Consumer Price Index (CPI). The 189.16 kg of 38 commercial species captured had a potential monetary value (PMV) of 408.63 €/ha. The annual value of adult fish (19 species) averaged 115.05 €/ha and juvenile fish (33 species) averaged 293.58 €/ha. Our findings highlight the value of surf zones and beaches as fishery resources, similar to other marine ecosystems. Our findings are useful for ongoing monitoring and research to enhance knowledge of these areas and the array of ecosystem services they provide.
... Even though many studies have analyzed local-level implementations of triplewins (Huxham et al., 2015;Naess et al., 2023;Ryan-Collins et al., 2011a;Tilahun et al., 2023;Wood et al., 2016) there is limited investigation on how institutional structures collaborate and compete in achieving triple-wins. In order to critically analyze CCD, we must not only ask what kinds of problems currently exemplify its multi-sector and multi-stakeholder elements but also whether new institutional processes are beginning to emerge that reflect the convergence of development and triple-win thinking with climate adaptation and mitigation. ...
... Climate Compatible Development is defined as development minimizing harm from climate change impacts by maximizing low-emission and climate-resilient development (Mitchell and Maxwell, 2010). Commonly referred to as "triple wins" describes the interrelated nature of adaptation, mitigation, and development, where progress in one component has implications for and depends on progress in the other two components (Anton et al., 2014;England et al., 2018;Huxham et al., 2015). Climate compatible development (CCD) is gaining traction as a conceptual framework for mainstreaming climate change mitigation and adaptation within development efforts. ...
... In addition to providing food and wood, mangroves act as blue carbon and are gaining popularity as a natural climate solution for human wellbeing. They also provide habitats for commercial fish species and biodiversity, regulate floods, storms, and erosion, offer recreational opportunities, and sequester atmospheric carbon, all of which have an increasing impact on climate change (Cameron et al., 2021;Friess, 2023;Huxham et al., 2015;Orchard et al., 2015;Ruslan et al., 2022;Rakotomahazo et al., 2023;Singh and Chudasama, 2021;Sudharmma Vishwanathan et al., 2023). ...
Climate Compatible Development (CCD), which aims to mitigate greenhouse gas emissions and promote economic growth while adjusting to the effects of climate change, necessitates integrated policy approaches across several sectors. However, little attention has been given to the types of institutional structures collaborating and competing in conceptualizing CCD and understanding its functioning. This paper develops and applies a qualitative analysis to determine the compatibility of national and local policies and multi-stakeholder roles with the aims of the three dimensions of CCD (development, climate adaptation, and climate mitigation) using the mangrove governance case. Results indicate that mangrove governance policies currently support shifts towards CCD, especially by national governments. The existence of Ministry of Development National Planning that play roles in formulating climate change policy and development planning in Indonesia proved beneficial for CCD attainment. However, several regulations showed that political intervention and sectoral interests were present in multilevel governance toward CCD. Institutional challenges in this context were described, particularly in the existence of a hierarchy of statutory powers in Indonesia.
... Mangroves are salt-tolerant intertidal ecosystems that provide various goods and services ranging from climate regulation through carbon sequestration (Donato et al., 2011;Githaiga et al., 2017), to provisional services such as exploitation for firewood and construction materials (Kairo et al., 2001). Similarly, the complex structure of the mangrove root system provides ideal nursery grounds for juvenile fish thus directly supporting local artisanal fisheries (Huxham et al., 2004(Huxham et al., , 2015. ...
... Gazi is a fishing village and fishing is a male-dominated activity. The observed high involvement of females in the survey was due to absence of majority of men being involved in fishing at sea and in fish distribution, while women dominated value addition and subsistence fish mongering within the village (Huxham et al., 2015), and active participation in Gazi Women Boardwalk ecotourism initiative. Most of the study's respondents were in their economically productive age (< 60 years), indicating that the success of any conservation or economic interventions would require careful consideration targeting this group as a priority (Ochiewo et al., 2020). ...
... This could either mean that education was either previously inaccessible or its relevance in the community was ignored. A study by Kenya Demo- (Kirui et al., 2008;Kairo et al., 2009;Huxham et al., 2015;Huff and Tonui, 2017). ...
Community Based Ecotourism (CBET) has the potential to both improve the conservation status of mangrove ecosystems and stimulate local economies. However, these ecotourism initiatives often fail due to a lack of active local participation, poor management and a lack of an appropriate benefit sharing scheme. This paper explores perceptions, opportunities and challenges of community mangrove-based ecotourism in Gazi Bay, Kenya. Data collected from household surveys, key informant interviews and focus group discussions were used to examine local perceptions, challenges and opportunities with respect to their participation in ecotourism as a tool for mangrove conservation. The results obtained indicated that 81.4 % of the Gazi village community was aware of the ecotourism activities being undertaken in the area with 62.8 % acknowledging the socio-economic as well as the environmental impacts of the ecotourism activities. Also, 66.0 % of the local community identified cultural traditions and local skills possessed by the community as having the potential to promote sustainable ecotourism activities in the area. For the design and implementation of any ecotourism venture and the management of mangroves to be sustainable, including that undertaken by the Gazi community, this study recommends prioritising effective local participation and capacity building. In addition, private sector involvement is essential for the mobilisation of resources to further enhance the management and conservation of mangroves in the long-term. The results provide key insights needed not only to improve the design and management of community-led marine conservation initiatives but also for ensuring that optimal conservation benefits are achieved.
... Smallerscale mangrove restoration projects (<1,000 ha) have higher rates of plant survival than larger projects [49] (Table 1). This occurs because smaller projects are often done by motivated landholders and community groups (e.g., the 117-ha Mikoko Pamoja project in Kenya [50], or 392 ha of shrimp pond restoration on Tanakeke Island in Indonesia [51]) and reflect concentrated management effort, even with limited resources. Smaller projects may work particularly well in contexts where sustainable extraction of resources from the mangroves is important for local communities [52]. ...
... Reconciling the advantages and disadvantages of large versus small restoration projects could be achieved through nesting smaller, community-led projects into larger projects. Government-supported schemes, such as community forestry nested within coastal adaptation planning, could help communities implement smaller restoration projects while also delivering landscape-scale benefits [50]. In small island states, which are particularly vulnerable to climate change, small restoration projects may provide the most appropriate scale and deliver the most benefits in providing a range of ecosystem services and supporting community livelihoods [51]. ...
... For example, common asset trusts [60] could maintain an inventory of funding opportunities for mangrove restoration projects. These projects would be endorsed by local stakeholders and adhere to social safeguards, including comanagement arrangements with communities and fair benefit sharing [50]. Such arrangements offer ESG investment funds a range of options with clearly articulated benefits to communities that can support long-term investment plans. ...
... Smallerscale mangrove restoration projects (<1,000 ha) have higher rates of plant survival than larger projects [49] (Table 1). This occurs because smaller projects are often done by motivated landholders and community groups (e.g., the 117-ha Mikoko Pamoja project in Kenya [50], or 392 ha of shrimp pond restoration on Tanakeke Island in Indonesia [51]) and reflect concentrated management effort, even with limited resources. Smaller projects may work particularly well in contexts where sustainable extraction of resources from the mangroves is important for local communities [52]. ...
... Reconciling the advantages and disadvantages of large versus small restoration projects could be achieved through nesting smaller, community-led projects into larger projects. Government-supported schemes, such as community forestry nested within coastal adaptation planning, could help communities implement smaller restoration projects while also delivering landscape-scale benefits [50]. In small island states, which are particularly vulnerable to climate change, small restoration projects may provide the most appropriate scale and deliver the most benefits in providing a range of ecosystem services and supporting community livelihoods [51]. ...
... For example, common asset trusts [60] could maintain an inventory of funding opportunities for mangrove restoration projects. These projects would be endorsed by local stakeholders and adhere to social safeguards, including comanagement arrangements with communities and fair benefit sharing [50]. Such arrangements offer ESG investment funds a range of options with clearly articulated benefits to communities that can support long-term investment plans. ...
Mangroves have been converted and degraded for decades. Rates of loss have declined over the past decades, but achieving resilient coastlines requires both conservation and restoration. Here, we outline the challenges for the global restoration of mangroves and what actions could enhance restoration. Ambitious global targets for mangrove restoration, if successful, could deliver global benefits of carbon sequestration, fisheries production, biodiversity, and coastal protection. However, large-scale mangrove planting efforts have often failed, and smaller projects may not deliver landscape-scale benefits, even though they are more suited to community management. Solutions to achieving global targets include reducing risks of large projects and increasing the uptake and effectiveness of smaller projects. Sustainable mangrove restoration requires investment in capacity building in communities and institutions, and mechanisms to match restoration opportunities with prospective supporters and investors. Global reporting standards will support adaptive management and help fully understand and monitor the benefits of mangrove restoration.
... On small islands such as Bhasan Char, higher LAI vegetation plays a crucial role in coastal protection by mitigating the effects of waves, tides, and storm surges by facilitating soil stabilization and preventing erosion (Feagin et al., 2009). A decrease in LAI can make the island more susceptible to coastal erosion, increased saline intrusion, and the loss of protective natural buffers, posing threats to infrastructure, human settlements, and ways of life (Huxham et al., 2015). Additionally, it can alter the ecosystem structure and functional processes of the island by contributing to a reduction in tree canopies, consequently altering the local climatic determinants such as temperature, sunlight, and humidity of that ecosystem (Atkins et al., 2023;Didham and Fagan, 2004;Nakamura et al., 2017). ...
... This can influence the rates of photosynthesis activities, biogeochemical processes, aboveground biomass, and overall ecosystem productivity. Furthermore, it can have a negative impact on biodiversity by influencing habitat loss, fragmentation, and a decline in habitat suitability for numerous plant and animal species (Almeida et al., 2019;Huxham et al., 2015;Nakamura et al., 2017). This can result in alterations in species composition, declines in populations, and the extinction of local flora and fauna. ...
Geomorphological changes have had numerous environmental impacts on landscape features, natural resources, landform stability, and ecosystem services on Bhasan Char Island in the Northern Bay of Bengal, Bangladesh. Therefore, the present study examines the morphological change of the island and its impacts on landscape features, landform stability, and coastal mangrove forest resources since its evolution. Optical satellite images from Landsat (TM and OLI) spanning from 2003 to 2023 have been used to assess geomorphological parameters using the bio-physical indices NDWI and MNDWI. A hybrid classification method involving unsupervised classification, supervised machine learning, and post-classification refinement was employed to precisely delineate landscape features and evaluate ecosystem services. Indeed, to evaluate forest cover health dynamics, the leaf area index (LAI) was estimated using the Google Earth Engine (GEE) cloud platform. The study results reveal that the geomorphology of the island was changed by fluvial and marine processes and responses, whereas only 3% of the landscape ages older than 19 years. Results also disclosed that built-up area construction for Rohingya nations drastically lost
7% of mangrove plantations over the last 8 years, from 2015 to 2023. The current research delivers crucial management strategies regarding further structural development by evading unplanned construction, hastening reforestation, and evolving the green belt along the existing embankment. The study findings will help policymakers, environmental managers, coastal and marine resource planners, ecologists, and geomorphologists take an eco-friendly sustainable development plan and conserve the coastal island and its landscape resources from the risk of fluvial and marine processes.
... The county has approximately 6,490 ha of mangrove forests concentrated in four major areas, Gazi, Shimoni, Vanga, and Funzi ( Figure 1). All nine mangrove species in Kenya are also found in Kwale county, with Rhizophora mucronata, Avicennia marina, and Ceriops tagal being the dominant species (Huxham et al. 2015). Mangrove forests are of great importance in ecological and economic to the county. ...
... However, the current population growth, doubled with the limited other sources of livelihood, will further increase fishing efforts excreted on coastal fisheries and may result in the depletion of the resources. For example, the projection of mangrove loss from 1992 -2010 was 13.5 % to the 20 years to come; with the BAU scenario 43%, the mangrove cover in Kwale County will be lost by 2032 (Huxham et al. 2015). Furthermore, this mangrove loss will negatively affect the other adjacent fish habitats, seagrasses, and coral reefs through sedimentation. ...
Ahmed HA, Mwaura F, Thenya T, Kairo JG. 2022. Coastal and mangrove economic valuation associated fisheries and problems in Kwale County, Kenya. Indo Pac J Ocean Life 6: 17-27. The coastal fisheries in Kenya are essential to the livelihoods of the coastal communities. They provide employment, income, and food and support other auxiliary industries. Despite the socio-economic importance of coastal fisheries, various anthropogenic and climate change impact threatened their existence. Fish habitats, including mangroves, coral reefs, and seagrasses, are threatened by human activities such as aquaculture, mangrove extraction, unplanned expansion of coastal cities, and marine pollution. Usually, coastal fisheries are also neglected in key policy-making agendas. That is attributed to inadequate information and a lack of data on the socio-economic contribution of coastal communities engaged in fisheries. This study aimed to estimate the economic value to provide crucial information for policy making of mangrove ecosystem-based coastal fisheries in Kwale County. The study also attempted to establish the coastal fishery production trend for the past decade, to estimate the economic value of mangrove ecosystems to fishery production, and the future of coastal fisheries projecting based on Climate Compatible Development (CCD) and Business As Usual (BAU) scenarios. Combining the primary data from interviews with 242 respondents with secondary data, including a decade of fish catch data, were analyzed, which exhibited a continuous increase from 1,908 tonnes in 2004 to 2,450 tonnes in 2013 coastal fisheries production. The coastal fisheries value was estimated to be Ksh.182 million (US 198/ha/year). Moreover, the estimated values could be much higher than the calculated ones because a considerable amount of fish caught is unrecorded. The future projections reveal that the scenario of Business As Usual (BAU) is not sustainable. Hence, the study demands a shift to the scenario of Climate Compatible Development (CCD), which incorporates mitigation measures, climate change adaptation, and investment in infrastructure. The study recommends reviewing the existing fishery policies regarding the unique characteristics of coastal fisheries to ensure sustainable exploitation and address the challenges. The research also recommends further economic studies on the coastal fisheries value chain.
... Mangrove forests are receiving growing attention in the climate change (CC) debate due to their capacity for 'blue carbon' sequestration (Friesen, Dunn, and Freeman 2017). 1 In tropical climates, mangrove ecosystems act as efficient carbon sinks in terms of their capacity for carbon sequestration in both above-ground biomass and below-ground biomass and in sediments (Donato et al. 2011;Huxham et al. 2015;Pham et al. 2018). Mangroves have an array of features that contribute to their resilience to significant environmental change such as storm damage and sea-level rise (SLR), and catastrophic events such as tsunamis, hurricanes, tidal bores and cyclones (Alongi 2008). ...
... Restoration of mangrove forests plays an important role in reducing the vulnerability of ecotourism to CC impacts, especially in coastal wetlands. Examples of effects of mangrove restoration include mitigating the impact of CC on sea turtles' terrestrial reproductive phase by providing shade to beaches and preventing coastal erosion (Fuentes, Fish, and Maynard 2012) and helping to protect against SLR by accumulating sediments and stabilizing weak shorelines (Huxham et al. 2015;Tuan et al. 2014;Gunawardena and Rowan 2005). Furthermore, restored and protected mangrove ecosystems prevent increased future vulnerability of mangroves due to urban expansion into low-lying coastal areas, protect buildings and infrastructure from damage caused by storms, and provide habitats for a variety of terrestrial, estuary and marine species, while creating new livelihood options in mangrove areas such as naturebased ecotourism (Tuan et al. 2014). ...
This study investigates tourist preferences and willingness to pay (WTP) for restoration of mangroves to reduce the effects of climate change (CC) on ecotourism at Rekawa coastal wetland, Sri Lanka, using a double bounded discrete choice elicitation format in a contingent valuation method. The survey also included socio-economic, demographic, and attitudinal characteristics of respondents. The results reveal that domestic and foreign tourists on average were willing to pay 2.65 USD and 11.4 USD per person, respectively, for mangrove restoration in Rekawa wetland. Among socio-demographic variables, education, age, and occupation had a significant effect on WTP. Furthermore, we show that foreign respondents with greater trust in the role of mangroves in mitigating the impacts of CC on sea turtles, and domestic tourists who believed effects of mangrove restoration in reducing the future vulnerability of urban expansion, were willing to pay more for the proposed mangrove restoration fund. Based on tourists’ preferences and WTP for mangrove protection, our results support the establishment of an environmental protection fund from the collection of tourists’ entrance fees using a dual pricing strategy, and the use of the funds for planting mangroves, patrolling mangrove areas to prevent illegal activities, and promoting nature-based tourism activities.
... In addition to their ecological value, mangroves have significant economic and social benefits. Several studies have shown that the involvement of local communities in mangrove management can improve community welfare while ensuring the sustainability of these ecosystems (Huxham et al., 2015;Jusoff & Taha, 2008). In Banda Aceh, this approach has the potential to integrate environmental conservation with improving community welfare. ...
Objective: This study aims to analyze the role of mangrove conservation in disaster mitigation and improving community welfare on the coast of Banda Aceh City. The research focuses on the effectiveness of community-based approaches to mangrove rehabilitation and their contribution to Sustainable Development Goals (SDGs), particularly SDG 11 (Sustainable Cities and Communities), SDG 13 (Climate Action), and SDG 15 (Life on Land). Theoretical Framework: This study is based on the theory of ecosystem services, where mangroves act as natural coastal protectors, carbon sinks, and sustainable economic resources for local communities. It also integrates disaster resilience and community development perspectives to highlight the socio-ecological benefits of mangrove conservation. Method: A qualitative approach is employed using interviews, field observations, and documentation studies in selected mangrove forest areas in Banda Aceh. This approach helps understand community participation in mangrove conservation and its socio-economic and environmental impacts. Results and Discussion: The findings reveal that community-based mangrove conservation enhances ecological awareness and provides economic benefits through ecotourism development. Additionally, mangroves effectively protect coastal areas from abrasion, storm surges, and the impacts of climate change, while aiding post-tsunami ecosystem rehabilitation. Research Implications: This study emphasizes the need for policy support to strengthen community empowerment in mangrove management and integrated ecotourism development. These policies can enhance coastal resilience, environmental sustainability, and socio-economic welfare, aligning with the objectives of SDG 11, SDG 13, and SDG 15. Originality/Value: This research offers a holistic perspective on mangrove conservation as a nature-based solution for disaster mitigation, environmental protection, and local economic development through ecotourism. By integrating SDG principles, this study contributes to both academic literature and practical policymaking in sustainable coastal management.
... 21 The slow uptake of participatory management in mangroves has been attributed to a lack of financial capacity, and KFS reluctance to give up power over the mangroves (Kairu et al., 2018;KI7, KI10). This is perhaps due to the official (taxes, permits, fees, fines) and unofficial incomes (from illegal logging) estimated at USD 1166 ha − 1 yr − 1 (Huxham et al., 2015). ...
... Similarly, Kenyan mangroves, though historically reduced by direct provisioning services such as wood and fuel harvesting, have recently been revalued for their indirect benefits to local fisheries, carbon sequestration, and cultural services. These benefits, which include flood risk reduction, are estimated in the hundreds of millions of dollars-far outweighing the benefits experienced in nearby urban Mombasa [84]. Similar additional benefits were determined to exist in other cases, such as that of rural Mozambique [87]. ...
... The range of reported costs for mangrove restoration is 225 to 216,000 USD ha À1 , not including the cost of the land (Lewis, 2005). However, not all ecosystem services provided can be given a "price," there are others, in particular on a local scale, which have an important value in sustaining the livelihoods of people, for example, the collection of wood for use as fuel for cooking though not having a high direct economic value (Huxham et al., 2015). ...
... One means of raising novel finance at the practitioner level is to develop mechanisms for the Payment for Ecosystem Services provided by seagrass ecosystems (UNEP, 2020b). Whilst Payment for Ecosystem Services frameworks have been successfully applied in mangrove restoration (Huxham et al., 2015), success across other terrestrial projects is limited (Erbaugh, 2022). Most, if not all, the discussion around the use of Payment for Ecosystem Services in seagrass focuses on credits to facilitate seagrass restoration. ...
Societal Impact Statement
Seagrass meadows are a globally important habitat subject to significant loss. As efforts to restore these sensitive habitats are hampered by their high cost and low levels of reliability, rigorous guidance is required to improve effectiveness and ensure they are cost‐effective. Here, we define 10 golden rules for how we can undertake seagrass restoration. We do this by considering that for seagrass restoration to be successful, it needs to take place with people and not against people. The framework we present aims to direct efforts for seagrass restoration that are holistic and achieve broad goals for people, biodiversity and the planet.
Summary
The world has lost a significant proportion of its seagrass, and although glimmers of hope for its recovery exist, losses and degradations continue. First and foremost, evidence highlights the need to put the world on a global pathway to seagrass net gain. Achieving this outcome requires that conservation of what remains is a priority, but reaching net gain requires seagrass coverage to increase at rates unlikely to be achieved naturally; large‐scale active restoration is required to fill this gap. Novel finance mechanisms aligned to the climate emergency and biodiversity crises are increasingly leading to larger scale restoration projects. However, no clear framework exists for developing or prioritising approaches. With seagrass restoration expensive and unreliable, rigorous guidance is required to improve effectiveness and ensure it is cost‐effective. Building on evidence from terrestrial and marine sources, here, we apply the ‘10 golden rules’ concept, first outlined for reforestation and later applied to coral reefs, to seagrass restoration. In doing so, we follow international standards for ecological restoration and view seagrass restoration in a broad context, whereby regeneration can be achieved either by planting or by enhancing and facilitating natural recovery. These rules somewhat differ from those on reforestation and coral reef restoration, principally due to the relative immaturity of seagrass restoration science. These 10 golden rules for seagrass restoration are placed within a coupled social‐ecological systems context, and we present a framework for conservation more broadly, to achieve multiple goals pertaining to people, biodiversity and the planet.
... Kenya's commitment to the pursuit of sustainable natural resource exploitation is further evidenced by signing and ratifying key multilateral environmental conventions, treaties, and agreements including United Nations Framework Convention on Climate Change (UNFCCC), the Kyoto Protocol, and Paris Agreement. Furthermore, to demonstrate leadership in climate action, the country has enacted several climate-specific policies including; National Climate Change Strategy (2010), Climate Change Act (2016), Climate Finance Policy (2018), National Climate Change Action Plan 2018-2022 (which is a 5-year rolling plan), and National Adaptation Plan (2015)(2016)(2017)(2018)(2019)(2020)(2021)(2022)(2023)(2024)(2025)(2026)(2027)(2028)(2029)(2030) which guides the climate actions of the National and County governments and other stakeholders. Others include; Energy Act 2012, Environmental Management and Coordination (Amendment) Act 2015, Green Economy Strategy Implementation Plan (GESIP) (2016)(2017)(2018)(2019)(2020)(2021)(2022)(2023)(2024)(2025)(2026)(2027)(2028)(2029)(2030), and Vision 2030. ...
Kenya is committed to the global efforts on climate change mitigation and adaptation as seen through investments in various sustainable green and blue economy projects. In this review paper, we present the current status of what has been done, particularly on the blue carbon offset initiatives undertaken in the mangrove and seaweed ecosystems as well as the decarbonization activities at the port of Mombasa and which should form reference information for local, regional, bilateral/multilateral partners, scientists and other climate change stakeholders. The blue carbon offset projects involve mangrove conservation, reforestation and carbon credit sale as well as seaweed farming. The initiatives have several unique features amongst which are the community-led income generation systems that simultaneously act as an inducement for ecosystem preservation, co-management and benefits sharing which are recipes for economic, socio-cultural, and environmental sustainability. A notable project impact is the conferment of economic power to the locals, particularly the women and the youth The model used embraces a collaborative approach involving multisectoral engagements of both the government, multilateral organizations, NGOs, and local communities. This integrated top-down (government) and bottom-up (local community) method deliberately targets the strengthening of economic development while ensuring sustainability.
... One means of raising novel finance at the practitioner level is to develop mechanisms for the Payment for Ecosystem Services (PES) provided by seagrass ecosystems (UNEP, 2020b). While PES frameworks have been successfully applied in mangrove restoration (Huxham et al., 2015), success across other terrestrial projects is limited (Erbaugh, 2022). Most, if not all the discussion around the use of PES in seagrass focuses on credits to facilitate seagrass restoration. ...
It is unequivocal that the world has lost a significant proportion of its seagrass, and although glimmers of hope exist, losses continue with many ongoing negative trajectories. First and foremost, we need to put the world on a global pathway to seagrass net gain. Conservation of what remains must be a priority, but we need to increase coverage at rates unlikely to be achieved naturally; large-scale active restoration is required to fill this gap. Novel finance mechanisms aligned to the climate emergency and biodiversity crises are increasingly leading to larger-scale restoration projects. However, no clear framework exists for developing or prioritising approaches. With seagrass restoration expensive and unreliable, rigorous guidance is required to improve effectiveness and ensure it is cost-effective, so that projects can begin to transform whole coastlines. Building on current evidence from both terrestrial and marine sources, here we apply the ‘10 golden rules’ concept, first outlined for reforestation and later applied to coral reefs, to seagrass restoration. In doing so, we follow the International Principles and Standards for the Practice of Ecological Restoration and view seagrass restoration in a broad context, whereby regeneration can be achieved by either planting or by enhancing and facilitating natural recovery. These rules somewhat differ from those on reforestation and coral reef restoration, principally due to the relative immaturity of seagrass restoration science compared to these comprehensively researched ecosystems. These 10 golden rules for seagrass restoration are placed within a coupled social-ecological systems (SES) context and we present a framework for conservation more broadly, to achieve multiple goals pertaining to people, biodiversity and the planet.
... These includes development of viviparous mode of reproduction, aerial roots (pneumatophores), salt exclusion and salt secretion to overcome the environmental stress and be able to survive in intertidal zones (Scholander, 1968;Shi et al., 2005), as well as development of silt root which does not only provide physical support to the plant but serves as a means of gaseous exchange in the root system through the lenticels (McKee, 1993), Scientists in recent times, started unveiling the immense potentials and benefits the mangrove forest and wetlands at large possess. This interests toward mangrove forest today has revealed several ecosystem services offered by the mangrove forest and includes; (1) facilitate the expansion of coastal areas as well as enhancing the productivity of marine life, (2) home for Biodiversity (landing point for migratory birds), (3) enhancement of coastal fisheries (4) nursery grounds for commercially and recreationally valued species, (5) filtration of sediment, nutrients and pollutants, (6) prevent soil erosion, (7) protect coastlines; from natural disasters such as floods and protection of coastal communities against strong winds and devastating sea waves and (8) Carbon sequestration (FAO, 2007;Komiyama et al., 2008;Hoang and Pham, 2010;Mukherjee et al., 2014;Huxham et al., 2015;Barbier, 2016). ...
This study investigated the effect of charcoal and spent engine oil on some growth indices of mangrove seedlings Rhizophora racemose G. Mayer grown in garden soil. The aim was to discover means of improving mangrove nursery growth and survival in the Niger Delta area of Nigeria. Rhizophora racemose was planted in garden soil amended with four different treatments: C (Garden soil only), PC (Garden soil + Charcoal), PCSEO (Garden soil + Charcoal + 6% Spent engine oil), and SSEO (Garden soil + 6% Spent engine oil), with three replicates each and randomized complete block design was adopted for the study. The effect of these treatments was monitored biweekly on some growth indices – plant height, leaf area, leaf length, number of leaves and stem girth, except for root length, number of roots, fresh weight, dry weight and chlorophyll content of R. racemosa which were obtained at 18th week after planting. The study revealed that PC treatment had the highest values for plant height, number of leaves, fresh weight, plant girth, root length when compared to other treatments (C, PCSEO and SSEO) while SSEO recorded the least values. Among the treatments, there were significant differences in the plant height, fresh weight and root length of R. racemosa at P = 0.05. The garden soil amended with charcoal improved the performance of R. racemosa than in spent engine oil alone (PC > PCSEO > SSEO). This could be attributed to the presence of heavy metals in spent engine oil. Again, the charcoal amended soil had higher values for growth indices when compared with the control (C) treatment. This suggest that charcoal has the potency of improving garden soil fertility, plant survival and productivity. Therefore, charcoal could be beneficial in environmental conservation, restoration of endangered forest especially the mangroves in the Niger Delta polluted with crude oil. The study recommends that, charcoal should be incorporated in reforestation and afforestation approaches of mangrove forests.
... The production function method employs dynamic modeling to simulate the contribution of pure public ecological products or quasi-public products (e.g., forest or forest rights trading) to economic output [35]. The replacement cost method determines the value of ecological products via the estimation of the cost required to replace pure public ecological products (e.g., water conservation), such as the cost of building and operating water treatment plants [36]. The contingent valuation method typically designs questionnaires to assess people's willingness to pay for pure public ecological products. ...
The value realization of ecological products is currently a rapidly evolving research topic; however, the definition of its concept, type, and operation mechanism remains relatively ambiguous. Operating in accordance with the PRISMA guidelines, this review employs keyword retrieval and screening, utilizing VOSviewer and word cloud mapping for analysis, in order to reveal three primary research domains related to ecological product value realization. Based on thorough screening and the analysis of high-quality literature, this study comprehensively accomplished the following objectives: (1) clarifying the fundamental concepts of ecosystem services and ecological products, their interrelationships, and the scope of research on ecological products; (2) clarifying the basic connotation of realizing the value of ecological products; (3) demonstrating government-led approaches, market-driven approaches and collaborative pathways for realizing the value of ecological products; (4) reviewing international cases related to realizing the value of public ecological products, quasi-public ecological products, and operational ecological products. The academic contributions of this study are (1) expanding the theoretical framework for realizing the value of ecological products; (2) providing a Chinese perspective on global research on pathways to realize value from ecological products; and (3) offering a novel approach to revitalizing regional economies and improving local ecological environments. Based on this research, several shortcomings and future directions in this field are identified: (1) insufficient clarity, standardization, and uniformity in evaluation and measurement methods; (2) the absence of comparison between ecological products and urban economic products; (3) inadequate exploration of multi-stakeholder allocation and coordination mechanisms; (4) limited research on the role of capital markets in allocating ecological product resources.
... Mangrove vegetation monitoring using indices and remote sensing has several advantages and disadvantages. The most common advantages include quantitative measures, in which the indices provide quantitative measures of mangrove vegetation, facilitating comparisons over time and between areas [53]. Accordingly, the indices can provide consistent measures of mangrove vegetation, allowing for long-term monitoring, and accessibility, where the indices can be easily calculated from remote sensing data, making them accessible to a wide range of researchers and practitioners [54]. ...
Normalized difference vegetation index (NDVI) is one of the parameters of vegetation that can be studied by remote sensing of land surface with Sentinel-2 (S-2) satellite image. The NDVI is a nondimensional index that depicts the difference in plant cover reflectivity between visible and near-infrared light and can be used to measure the density of green on a piece of land. On the other hand, the dual-pol radar vegetation index (DpRVI) is one of the indices studied using multispectral synthetic aperture radar (SAR) images. Researchers have identified that SAR images are highly sensitive to identify the buildup of biomass from leaf vegetative growth to the flowering stage. Vegetation biophysical characteristics such as the leaf area index (LAI), vegetation water content, and biomass are frequently used as essential system parameters in remote sensing data assimilation for agricultural production models. In the current study, we have used LAI as a system parameter. The findings of the study revealed that the optical data (NDVI) showed a high correlation (up to 0.712) with LAI and a low root-mean-square error (0.0296) compared to microwave data with 0.4523 root-mean-square error. The NDVI, LAI, and DpRVI mean values all decreased between 2019 and 2020. While the DpRVI continued to decline between 2020 and 2021, the NDVI and LAI saw an increase over the same period, which was likely caused by an increase in the study area’s average annual rainfall and the cautious stance of the Red Global (RSG) project on sustainability.
... Incentives could include financial compensation for propagule collection and planting (Gallup et al., 2020), ecosystem service payments at the community level (Thompson, 2018), or approvals for sustainable harvesting (Hamza et al., 2023). Introducing incentives when negotiating with community members and private land holders may persuade them to shift their views on allowing restoration to occur and thereby ensuring mangrove survival (Canning et al., 2021;Huxham et al., 2015). ...
Accurately accounting for the many variables which can influence restoration feasibility is critical to achieve desired outcomes, yet robust frameworks to assess feasibility are lacking. In conservation planning, feasibility can be defined as ‘the probability that a project will achieve its stated objectives’. Often, important biophysical, social, governance, logistical, or resource factors that co-vary across space and determine feasibility are not explicitly included in restoration planning, even though this could enhance outcomes. Here, we present a four-step approach to include feasibility into restoration planning, using mangrove restoration as a case study. Step 1 uses expert knowledge and published literature to identify relevant spatial gradients and explore feasibility factors spanning biophysical, governance, social, logistical, and resource realms which influence restoration outcomes. Step 2 describes the functional relationships between specific feasibility factors and spatial gradient(s) of interest. Step 3 assesses how management interventions could increase feasibility of specific factors. Step 4 analyses ‘joint feasibility’ of multiple feasibility factors and identifies whether further management interventions are required. The approach provides a systematic and repeatable evaluation of multiple feasibility factors and is applicable in spatial planning to enhance restoration outcomes.
... Scenarios and stakeholder engagement are suggested as key tools to analyse potential trade-offs and co-benefits in these various restoration objectives and outcomes across space, time and stakeholders [20,27,28]. Their propensity for integrating diverse data collection and analysis [15,29] alongside facilitating participatory discussion allows for more social and economic dimensions to be captured in a discipline that has traditionally focussed on evaluating environmental components alone [30][31][32]. In contrast, Bremer et al., [15] quantified ecological and economic outcomes of scenarios alongside qualitative evaluation of cultural outcomes to understand trade-offs between them. ...
Background and context
The scale of land degradation worldwide has led to nearly one billion hectares committed to restoration globally. However, achieving such restoration targets will necessitate complex trade-offs against limited time, competing knowledge, costs, resources and varying stakeholder and societal preferences. Participatory scenarios allow a way to identify collaborative solutions for restoration planning and implementation best suited for the local cultures and societies they are tied to. They can be used to navigate uncertainties surrounding future trajectories of restored areas by evaluating trade-offs in outcomes. This research aims to systematically map the evidence on the use of participatory scenarios in restoration planning. We use the following research question: What evidence exists on the use of participatory scenarios in ecological restoration? This is answered by examining the characteristics of the evidence base, types of study design, types of outcomes, trade-offs in outcomes, and the role of participants.
Methods
A comprehensive and reproducible search strategy was followed using bibliographic databases, web-based searches, and targeted searching. Search results underwent a two-step screening process according to eligibility criteria. Metadata on key areas of interest were extracted from included texts and were narratively synthesised alongside data visualisations to answer the research questions.
Review findings
18,612 records were initially identified, and 106 articles were included in the final map. Most studies were conducted in Europe and North America, focusing on restoring agricultural land or forests. Most texts used mixed methods and explored multiple outcome types, but environmental outcomes were the most assessed. Within environmental outcomes, indicators for ecological function were assessed more frequently than structural or compositional indicators. The most common reason for choosing outcomes and indicators was stakeholder interest. Trade-offs in social, ecological, and economic outcomes were mainly examined across space using mapping techniques, while far fewer studies looked at trade-offs across stakeholders and time. Participants were mostly included in the scenario creation step and were usually chosen purposefully by the research team.
Conclusions
It is difficult to understand how useful scenarios are for restoration planning because few texts reported how scenarios fed into the process. Despite this, the range of outcomes used and different method types adopted suggests participatory scenarios allow for integrating different knowledge and approaches, alongside facilitating the use of qualitative or semi-quantitative data when this is more appropriate or quantitative data is not widely available. To better use participatory scenarios as a tool for ecological restoration planning, decision-makers can push for greater levels and definitions of participation from the offset of restoration projects with specified, regular, and structured communication and participation channels. We also recommend more systematic methods of participant selection, such as stakeholder analysis. Further research is needed to understand the effectiveness of participatory scenarios in restoration planning and whether the participation of stakeholders was successful in meeting objectives. To improve the evidence base, future studies should clearly evaluate their effectiveness in the restoration planning process and their success in meeting their participatory objectives.
... In order to understand how mangrove forests are changing in the context of natural and anthropogenic interventions, and to assess the impact of these changes on marine habitats and ecosystems (Carvalho et al. 2019), it is crucial to map mangrove forests and the changes in their area in detail (Earp et al. 2018). Due to the complicated distribution of mangrove forests over vast and isolated areas, relatively little mapping and modelling has been done despite their importance and progressive destruction (Wang et al. 2019a, b;Huxham et al. 2015). In recent decades, remote sensing (RS) technology has become a reliable source of information for mapping and monitoring the dynamics of mangrove forests around the world (Avtar et al. 2017;Kuenzer et al. 2011). ...
Mangrove ecosystems provide numerous benefits, including carbon storage, coastal protection and food for marine organisms. However, mapping and monitoring of mangrove status in some regions, such as the Red Sea area, has been hindered by a lack of data, accurate and precise maps and technical expertise. In this study, an advanced machine learning algorithm was proposed to produce an accurate and precise high-resolution land use map that includes mangroves in the Al Wajh Bank habitat in northeastern Saudi Arabia. To achieve this, high-resolution multispectral images were generated using an image fusion technique, and machine learning algorithms were applied, including artificial neural networks, random forests and support vector machine algorithms. The performance of the models was evaluated using various matrices, and changes in mangrove distribution and connectivity were assessed using the landscape fragmentation model and Getis-Ord statistics. The research gap that this study aims to address is the lack of accurate and precise mapping and assessment of mangrove status in the Red Sea area, particularly in data-scarce regions. Our study produced high-resolution mobile laser scanning (MLS) imagery of 15-m length for 2014 and 2022, and trained 5, 6 and 9 models for artificial neural networks, support vector machines and random forests (RF) to predict land use and land cover maps using 15-m and 30-m resolution MLS images. The best models were identified using error matrices, and it was found that RF outperformed other models. According to the 15-m resolution map of 2022 and the best models of RF, the mangrove cover in the Al Wajh Bank is 27.6 km², which increased to 34.99 km² in the case of the 30-m resolution image of 2022, and was 11.94 km² in 2014, indicating a doubling of the mangrove area. Landscape structure analysis revealed an increase in small core and hotspot areas, which were converted into medium core and very large hotspot areas in 2014. New mangrove areas were identified in the form of patches, edges, potholes and coldspots. The connectivity model showed an increase in connectivity over time, promoting biodiversity. Our study contributes to the promotion of the protection, conservation and planting of mangroves in the Red Sea area.
... Kenya has been experiencing a rapid increase in environmental regulations over the past few decades (Rajé et al., 2018). The country's government has been implementing stringent measures to protect its environment and natural resources from degradation caused by industrial activities (Huxham et al., 2015;Rajé et al., 2018). Evolution of these regulations can be traced back to the 1970s when Kenya established its first environmental law, the Environmental Management and Coordination Act (EMCA) in 1999 (Kotzé & Soyapi, 2021;Haregu et al., 2017) . ...
As the environment continues to become increasingly constrained, the relationship between environmental protection and economic growth is becoming a crucial subject. This study considered Kenya’s new environmental regulation laws on emission control as a "quasi-natural experiment" to assess the impact of stringent environmental regulations of emission control on industrial’ export performance using a difference-in-differences (DID) framework. The study uses a panel data of 137 firms from the Export Processing Zone (EPZ) and Pooled OLS analysis with agricultural food industry as the control group. The heterogeneous impacts of firms with different size level is investigated. The study reveals that stringent environmental regulations of emission control enhances export intensity among the EPZ firms. Micro firm’s export intensity gains the highest (18.21 %,) from stringent environmental regulations on emission control than both small (11.09%) and large firms (9.50%). The study also found a significant association between export performance and firm ownership status, location and experience in exporting. The study thus recommends applicability of stringent environmental regulation in achieving both export performance and environmental improvement in Kenya.
... Therefore, high CI implies older, less dense trees with a more diverse mangrove species mix, as found in mature, old-growth forests. In Kenya, the old growth forests with high CI values have the highest stocks of carbon and are thus the most important carbon sinks (Huxham et al., 2015). However, these results suggest that a lower CI is better for fish, and this is consistent with the idea that fish prefer very dense stands, which are often younger and less likely to be multispecies. ...
Mangroves often support rich fish and crustacean communities, although faunal abundance and diversity show strong spatiotemporal variability. Consistent patterns in mangrove animal communities might be dictated by forest characteristics, by seascape context or by some combination of these factors. Predicting drivers of spatial heterogeneity in mangrove faunal communities can better support the zoning of forests for management purposes, for example by identifying sites important for fisheries nursery provision.
We sampled 14 sites within a large (4000 ha) mangrove forest in Kenya, quarterly over a period of 2 years. There were clear and consistent differences in the quality of sites for fish and crustacean abundance and diversity.
Forest characteristics (as summarised by the complexity index, CI) and seascape metrics (the presence, area and configuration of contiguous seagrass) were strong predictors of site differences. However, they showed opposite influences on dominant members of the fish and crustacean faunas, with CI correlated negatively with fishes and positively with crustaceans, and seagrass area correlated positively with fishes and negatively with crustaceans.
Synthesis and applications. Sites within the same mangrove forest exhibit consistent differences in fish and crustacean abundance. However, the fish and crustacean communities (and particularly dominant species within them) act differently in response to forest and seascape characteristics. Old growth, mature forest, set in a seascape of seagrass patches with bare sediment, was associated with highest crustacean abundance. In contrast, denser smaller trees and seascapes with larger, continuous areas of seagrass correlated better with fish abundance. Zoning for management, as mandated in new Kenyan policy, will need to consider these differences in seascape use between fish and crustaceans.
... Moreover, communities have their source of livelihood from the immense presence of mangrove forest which provides a variety of good and services such as breeding sites for fish and crabs which they sell for economic empowerment. Notably, sustainable mangrove management's vision revolves around community participation to deescalate the growing environmental degradation from competing interests and the effects of climate change experienced by the community [14, 20,21]. ...
Community Participation is fundamental for sustainable mangrove management which enhances environmental sustainability. This study analyses the setting of governance standards using policy frameworks. The study adopted a correlational research design and used a mixed methods approach. It shows awareness of policies supporting community participation in mangrove conservation was at 94.6%. The respondents who knew existing policies of the forest conservation and management act were at 27.80% closely followed by those with knowledge of local agreement with Kenya Forest Service at 25.40%, and those who practiced community/traditional by-laws at 21.80%. Notably, 18.40% of the respondents indicated knowledge of the national mangrove management plan while only 6.70% expressed awareness of the public participation law. Community participation is overly affected by gender perceptions in the education level, age, and knowledge of governance standards. The findings indicate 71% of women have not participated in setting governance standards as well as 69.20% of men. 81% of respondents disagree with the existence of county government policies in mangrove conservation. There is a lack of enough participation in setting governance standards towards the existing policy framework, affecting mangrove management.
... . This values include regulatory ecological functions, which lead to indirect benefits such as flood control, storm protection, nutrient retention, nursery grounds for different species, and main erosion control [27][28][29][30]. As the government considers mangrove planting for coastal protection to replace dykes, the indirect value can be considered as a replacement value for investment in the construction and maintenance of a sea dyke system. ...
In this paper the values of mangrove ecosystem service in Soc Trang and Bac Lieu provinces, Vietnam were presented.
... The current study expands the scope and geographic coverage of previous research by investigating the socio-ecology of mangroves in Lamu County, in northern Kenya, aiming to advance the understanding of how resource use and the perceptions about environmental changes are influenced by different sociodemographic factors. It is estimated that 80% of community residing adjacent to mangroves in Kenya derives about 70% of their wood requirements from the forest (Huxham et al. 2015). According to the Kenya's National Mangrove Ecosystem Management plan (2017)(2018)(2019)(2020)(2021)(2022)(2023)(2024)(2025)(2026)(2027), at least 40% of the mangrove forests in the country are in degraded conditions. ...
Deforestation and overexploitation of mangrove forests are affecting the livelihoods of millions of families that rely on their ecosystem services. Understanding local perceptions about the status and threats to mangroves is therefore crucial in addressing this issue. This research aims to enhance understanding of how sociodemographic factors influence resource use and perceptions of environmental changes through a questionnaire survey (n = 592 households) in five locations in Lamu County, home to 62% of Kenya's mangroves. The results highlight the variability of mangrove use, ecosystem service recognition, and perceptions and drivers of change across locations, which are influenced by sociodemographic factors such as gender, education, and occupation. Although 89% of respondents reported using mangrove products, only 56% were able to identify mangrove ecosystem services, with those without formal education being less likely to recognize them. Interestingly, 50% of respondents perceived an increase in mangrove cover, contrary to research showing mangrove loss in the area over the last decade. Results show that communities are diverse and perceptions vary between groups, suggesting that implementing uniform management measures may be incomplete or ineffective. Awareness campaigns and capacity-building efforts must be tailored to reduce misperceptions about the state of local resources and to address the specific needs and challenges faced by different groups. Recommendations made here are widely applicable to promote more inclusive and sustainable community engagement in the management of natural resources in developing countries worldwide.
... Based on the estimate, Barbier (2007) [49] estimated the erosion prevention service of mangroves of Thailand for protecting the shoreline with a 75-meter width stand of mangrove to be approximately US$13.48 per m 2 , or US$134800/ha (1996 prices). Shoreline loss after mangrove removal and hard structures establishment and maintenance to protect Kenya coast was estimated at US$ 20.81 m 2 /yr., US$ 395/ ha (Mark Huxham et al. 2015) [57] . Mangroves help to purify and maintain freshwater sources in coastal areas. ...
Mangroves are a group of trees and shrubs that live in the coastal intertidal zone. Mangroves have been distributed in low-energy, tidal shorelines between latitudes in tropical and subtropical areas. Mangroves are important productive ecosystems in coastal areas. Mangrove ecosystems are rich in biodiversity and provide a wide range of goods and services to human communities living in coastal areas including wood and non-wood forest products, fisheries, medicines, tannins, apiculture, wildlife resources, fishery, recreation, ecotourism, bio-filtration, nursery grounds, coastal protection, and carbon sequestration. Mangroves are bio shields of the coast and protect people from disasters like tsunamis, and cyclones. Mangroves support shoreline protection, sediment accretion, and, other functions. Mangrove cover in coastal areas of India is 559098.62 ha. They have been discontinuously distributed in 42859 patches of the coastal areas. India's coastal States and UTs are distributed with mangrove ecosystems except the UT of Lakshadweep. Benefits from mangroves are often ignored by industry and local inhabitants since the values of goods and services and their equivalent economic benefits are derived from the mangroves of India. This study aims to analyse various benefits of mangroves and estimate their equivalent economic benefit to inform the conservation benefits of mangroves. This study has followed the Millennium Ecosystem Assessment framework. The average total economic benefit of mangroves' goods and services is the equivalent economic values of India's mangroves range between Rs. 92662/-/ha/yr., = US72008.47/-/ha/yr. (maximum) with an average total economic benefit of Rs. 958766/ha-/yr = US1148.40 Rs./yr (Average) to the welfare of coastal communities. The ecosystem value shall support policy decisions and awareness creation on conservation benefits and sustainable utilisation of goods and services of the mangrove ecosystem.
... The trees that make up the vegetation in the mangrove forest will later play a role in the formation of a microclimate, improving air quality and reducing carbon dioxide, as well as protecting the city's water supply [27]. photosynthesis and respiration [28]. Mangrove forests with good tree conditions will certainly have good physiological processes from each plant. ...
The condition of mangrove forests in East Lampung Regency is currently experiencing degradation, resulting in the function of mangrove forests being reduced, especially in preventing natural disasters. This research is the third-year measurement of the activities of monitoring the health of mangrove forests in East Lampung Regency. The purpose of this study was to determine the value and trend category of the health condition of the mangrove forest in East Lampung Regency. The stages of this research, namely: measuring the health trend of mangrove forests in the six FHM clusters that have been built and analysing the data using the Forest Health Assessment Information System software. The results of this study indicate that the trend value of the health condition of mangrove forests in each location is Kuala Penet (8.64-20.90) with a good category because CL-1 and CL-2 are constant, Margasari (2.52-5.57) in the bad category because CL-3 and CL-4 decreased, and Purworejo (5.58-8.63) in the moderate category because CL-5 and CL-6 increased. Thus, the average trend value of the health condition of the mangrove forest in East Lampung Regency (7.70) is in the moderate category. This can provide information to the community on preparedness in dealing with natural disasters.
... We suggest organizing provincial-level meetings in the coastal provinces at least every four months specifically to discuss mangrove-related matters so that all stakeholders can have a clear understanding of how other stakeholders perceive mangroves. Continuous engagement of stakeholders is an important factor to improve mangrove management (Huxham et al., 2015). Most of our respondents knew that mangrove management is mandated by jurisdiction. ...
Understanding the extent of collaboration among stakeholders is key to supporting mangrove management. Despite the existence of robust policies, collaboration among stakeholders of mangrove co-management remains largely unexplored in Sri Lanka. This was partly due to the civil war, natural disasters, and other socio-economic changes over the past 30 years. Our study aimed to identify the collaboration between stakeholders of mangrove management and their perceptions regarding mangrove co-management in Sri Lanka using social network analysis and content analysis. Surveys were conducted in all five coastal provinces of Sri Lanka. Stakeholders included in the study were from government departments, non-governmental organizations, and private institutes. Our results showed that there were differences between coastal provinces in the mangrove management networks, specifically in the number of stakeholders involved and their degree of collaboration. Some important stakeholders (for example the Land Use and Policy Planning Department) were excluded from the social networks in certain provinces (Eastern and Western provinces). There were various issues hampering effective mangrove management such as inefficient communication, inconsistencies between policies, and insufficient financial capacity of government stakeholders responsible for policy implementation. According to the stakeholders in our study, providing mangrove management initiatives with long-term collaboration, post-care, continuous monitoring, and funding may help to overcome these challenges. Additionally, we suggest the establishment of a common platform to coordinate stakeholders. We further encourage increasing the participation of academics, researchers, and students from national universities in the mangrove co-management of Sri Lanka. Insights from this island-wide survey can be adapted to mangrove and other natural resource management trajectories in other countries as well.
... As such, with an increasing international efforts to fight against climate change and as a result of the growing recognition of the high capacity of mangroves to either sequester or store large quantities of carbon [15,16], mangrove PES has been considered as part of the mechanisms to Reduce Emissions from Deforestation and Forest Degradation (REDD+) promoted by the United Nations Framework Convention on Climate Change (UNFCCC) [17]. Mikoko Pamoja mangrove carbon project of Kenya [18] is an example of successful mangrove PES in the world where local communities of the Gazi bay of Kenya (seller of ES) generate an annual income estimated at US$12,000 through the sale of the carbon sequestered by their mangroves. This credit is earned from the conservation and restoration of their mangroves which sequester 3000 metric tons of CO2-equivalent/year and sold to carbon buyers (e.g. ...
Although Payments for Ecosystem Services schemes emerged since the 1980 ′ s to manage forest ecosystems, their application to mangrove forests is still recent, and evidence of their effectiveness is still questioned towards the complex legal status of mangroves. This study explored the context of policy and institution regarding the Payment for Ecosystem Services (PES) implemented in the mangroves of the Southwestern Madagascar. We used Policy content analysis to examine the interactions between the Madagascar sectoral policies and the PES design frameworks developed under the Reduction of Emission from Deforestation and forest Degradation (REDD+) mechanism of the United Nations Framework Convention on Climate Change. In addition, semi-structured interviews with national and local stakeholders were conducted to identify i) institutional interplay between PES and mangroves and ii) challenges faced with the implementation of PES in the mangroves. We found that environmental, fisheries and land use planning policies that concern mangrove management are coherent with the frameworks and supportive of PES implementation. Lack of clear legal frameworks and coordination between the sectoral ministries, weakness of government organisations due to political instability, and limited local governance capacity are the major challenges for the implementation of PES schemes in mangroves. These led to lower motivation to collaborate in mangrove conservation efforts among the members of local communities. We emphasized that the existence of the mangrove PES initiative like in the Baie des Assassins could be a catalyst for Madagascar to develop clear policy, legislation, and institutions to support effective implementation of the PES schemes in mangroves.
... Although Mida Creek is globally recognized as an Important Bird Area (IBA) and is part of Watamu Marine Park and Reserve (Owuor et al., 2017;Birdlife International, 2020), increasing human population and an increase in demand for natural resources has led to continued degradation and loss of the mangrove forest and associated ecosystem services (Alemayehu, 2016). Undervaluation of the benefits provided by mangrove forests has led to them being rarely considered when resource management decisions are made (Huxham et al., 2015). This hampers awareness creation and policy formulation processes aimed at protecting mangroves. ...
... The labor of fuelwood collection in Africa is performed overwhelmingly by poor women and girls. Standard economic assessments may underestimate the value of this fuelwood provision and the opportunity costs, such as time not spent studying or at school, suffered by the girls (Huxham et al., 2015). Cash income is strongly correlated with mangrove fuelwood use. ...
The functional and ecological importance of dead wood in terrestrial forests is widely recognized and researched. In contrast, much less is known about dead wood in mangrove forests, despite its known or demonstrated contribution to key ecological processes including nutrient cycling and seedling recruitment. In addition, mangrove dead wood provides an important service for millions of people; harvesting wood for fuel is widespread in mangroves and is often vital for the lives and wellbeing of people living close to these forests. Limited information on stocks and production, and the drivers of these, means that understanding and managing the supply of this service is difficult. Here we conduct a systematic review of the literature on dead wood stocks and production in mangrove ecosystems. Four hundred and seventy-five subject articles were found, with large gaps in geography, species, and forest type. After excluding records that were not relevant to our study and those from mass mortality events, 68 studies remained. We also added new data from 9 sites in Kenya, to provide overall estimates of mean (± SD) stocks of dead wood of 16.85 ± 25.35 Mg ha−1 standing and 29.92 ± 36.72 Mg ha−1 downed. Our analysis shows that potentially, higher stocks of dead wood might be found in forests without evidence of human impact. Average mean production with 95% CI was 6.30, 3.10–11.40 Mg ha−1 yr−1. Estimates of daily wood use were applied to give likely demands on wood from mangrove dependent communities. This review reveals the paucity of research on mangrove dead wood, hence these estimates of average stocks and productivity remain very limited and thus, further work on the dynamics of dead wood in mangroves and the ecological effects of its removal is needed.
... The Kenyan government and wildlife service has been very proactive to restore and rehabilitate the marine habitats of this country (Ochieng and Erftemeijer 2003). Huxham et al. (2015) exemplified that devising climate-compatible development schemes in consultation with local stakeholders can lead to fruitful conservation of coastal ecosystems like mangroves. Owuor et al. (2019) recorded a community's willingness to pay to ensure and in return for continued ecosystem services. ...
The blue carbon ecosystems like mangroves, seagrasses, and salt marshes are facing severe threats throughout the globe due to several natural and anthropogenic factors. The persistence of such imminent threats has led to a dire need for conservation and management plans for these crucial marine habitats. The present chapter reviewed the overall conservation scenario of the blue carbon habitats in the periphery of the Indian Ocean. Preservation, restoration, rehabilitation, afforestation, and controlled felling maintaining forestry rules are some of the well-defined protocols that are implemented by several Indian Ocean countries to safeguard the blue carbon habitats. However, the involvement of local stakeholders, especially the communities exclusively relying on the services of these ecosystems should be included within the management framework. Several studies carried out in different countries unequivocally indicated that stringent law enforcement from the top authority toward the marginalized society residing in and around the blue carbon ecosystems often does not come up with the desired level of conservation. Instead, a consultation with the local community on a small-scale basis, understanding their needs and views, and accordingly cascading the region-specific conservation protocols to the higher officials in charge of the execution could lead to better outcomes. Poverty alleviation and proportionate access to ecosystem services should be given priority to effectively conserve these marine habitats. In several small island nations, where these ecosystems occupy small areas, spreading awareness of their benefits and roles is a top priority. In many western Indian Ocean countries, baseline studies are required in the first place to comment anything on the conservation status and needs. Overall, this chapter highlighted and discussed the present scenario of conservation status in the Indian Ocean countries, the shortfalls observed by the scientific community, and the endeavors that need to be undertaken soon.
... Kenya has ten of the mangrove species that occur in the East African Coast Multi-stakeholder approach in natural resources management in vital in decision-making, contributes to quality policy decisions and enhances policy acceptance during implementation [11,12]. The engagement of multi-stakeholders helps in coordination of policies across sectors in conservation and management of mangrove forest ecosystems [13]. Public participation increases confidence and enthusiasm in mangrove forests conservation and provides a focus for construction of common perspectives, agreed on solutions and interactions to reach consensus regarding the set objectives [12]. ...
Multi-stakeholder approach has an overall improvement in conservation and management of mangrove forests resources, more so with a functional coordination framework among stakeholders. Mida creek and Gongoni-Marereni sites were compared in terms of the presence of the multi-stakeholders and the level of coordination and cooperation among stakeholders in conservation of mangrove forests. Data was gathered through a semi-structured interview questionnaire from Key Informants from the stakeholders present in the two sites. The data collected captured stakeholder presence on site, participation in mangrove conservation, and coordination and cooperation with others. There was a variation in multi-stakeholder participation in the two sites. Gongoni-Marereni site had less stakeholders compared to Mida creek which had more, with the latter having a greater participation of stakeholders. The Gongoni-Marereni site mangroves were degraded while in Mida creek had healthy mangroves.
Regulating ecosystem services (RES) play a very critical role in the sustenance of environmental health and human well-being, yet their valuation remains a complex and dynamic field. The variety of valuation methods, each with its strengths and limitations, as well as the limited methodological guidance for the selection of appropriate methods, poses a challenge in the valuation of RES. This review examined RES valuation studies in Africa, focusing on growth trends, methodological preferences, and policy reporting approaches. Drawing on the existing literature, we also explored the use of decision trees to support the choice of appropriate methods. A synthesis of peer-reviewed literature identified 31 studies, and their analysis revealed the dominant use of single-valuation methods in the assessment of RES and a varied growth rate in the number of valuation studies over the period under review. Furthermore, a notable heterogeneity exists in the methods used to report policy impact across various value assessments. This review contributes valuable insights into the current state of RES valuation research, necessary to advance methodologies, guide future research, and inform policy discussions on the sustainable management of ecosystems.
В статье представлено описание и классификация методов оценки природного капитала. Описаны методы оценки экосистемных услуг как основы для оценки природного капитала. Отмечен синергетический эффект методов оценки экосистемных услуг. Результаты анализа могут быть использованы в процессах разработки и реализации политики природопользования различного уровня.
The articledescribes the description and classification of methods for assessing natural capital. Methods for assessing ecosystem services as a basis for assessing natural capital are described. The synergistic effect of methods for assessing ecosystem services is noted. The results of the analysis can be used in the processes of development and implementation of environmental management policies at various levels.
Mangrove ecosystem has an important role in reducing carbon in the environment. There has been massive conversion of mangrove area into ponds and buildings in the current period. Therefore, the species diversity and carbon sequestration capacity of the mangrove ecosystem must be evaluated to monitor its function. This research aims to evaluate the species diversity and the sequestered carbon in the mangrove ecosystem of Karimunjawa National Park (KNP), Indonesia. The species analysis in the 3 research sites, 9 transects, and 27 plots (10 m × 10 m) that was obtained using the quadrat sampling method. Allometric equations, Shannon–Wiener, and evenness indices were used to estimate the standing biomass and carbon, species diversity, and distribution, respectively. The sediment samples were obtained at a depth of 100 cm and divided into three depths, namely, 0–33, 34–67, and 68–100 cm. The carbon content of mangrove sediments was analyzed in the laboratory using the Walkley–Black method. The results revealed that mangroves in the KNP have moderate diversity and even distribution. The estimated carbon in the mangrove stand was 146.22 t C ha –1 and the estimated carbon stock in the sediment was around 360.61 t C ha–1. Although the mangrove ecosystem in Karimunjawa National Park is still in a stable condition, it is necessary to monitor its changes due to the anthropogenic activities.
Identifying contaminants in agricultural plant food products (APFPs) is a major problem. In this study, we developed a single-step extraction and integrated non-target data acquisition (INDA) workflow for increasing hazardous substances coverage. D-optimal experimental designs were applied to optimize filter plate extraction (FPE) for one-single extraction of multipolar hazardous substances. The vDIA mode was used to collect all precursor ion fragments within the range to supplement data loss caused by DDA mode. The underlying principle of vDIA is to increase the utilization rate of MS2 spectra that are likely to identify a maximum number and minimum amounts of hazardous substances. Compared with traditional DDA mode alone, a combination of the two modes increased the rate of identification of hazardous substances by 18.5%. The molecular network of hazardous substance provided by GNPS could enable some metabolites and structure-related products to discover potentially hazardous substance.
Abstract Storylines are introduced in climate science to provide unity of discourse, integrate the physical and socioeconomic components of phenomena, and make climate evolution more tangible. The use of this concept by multiple scholar communities and the novelty of some of its applications renders the concept ambiguous nonetheless, because the term hides behind a wide range of purposes, understandings, and methodologies. This semi‐systematic literature review identifies three approaches that use storylines as a keystone concept: scenarios—familiar for their use in IPCC reports—discourse‐analytical approaches, and physical climate storylines. After screening peer‐reviewed articles that mention climate and storylines, 270 articles are selected, with 158, 55, and 57 in each category. The results indicate that each scholarly community works with a finite and different set of methods and diverging understandings. Moreover, these approaches have received criticism in their assembly of storylines: either for lacking explicitness or for the homogeneity of expertise involved. This article proposes that cross‐pollination among the approaches can improve the usefulness and usability of climate‐related storylines. Among good practices are the involvement of a broader range of scientific disciplines and expertise, use of mixed‐methods, assessment of storylines against a wider set of quality criteria, and targeted stakeholder participation in key stages of the process.
Executive summary Thirty-five euros. That is what you approximately pay in Finland for the emission of one metric ton of CO2. However, metric tons of CO2 may become cheaper depending on your location. In Ireland for instance emitting one metric ton of CO2 only costs fifteen euros. But aren't the externalities caused by CO2 emissions equal around the world? Why, then, does the value given to a metric ton of carbon differ from one place to another? And why are we giving a monetary value to carbon emissions? In fact, with the scientific proof that climate change is happening, addressing it has become a major environmental, as well as social and economic issue. Governments, companies, and civil society are trying to find appropriate responses to mitigate it. However, in order to do so, we must first understand climate change. We must figure out what the long term effects of climate change are and how to measure these effects. Hence, there needs to be a common language and methodology that can determine the real impact on our planet. Therefore, our objective is to analyze if the creation of such a common framework is possible and how would it be conceptualized. Carbon valuation has become the predominant discourse among experts and policymakers in the last decades as the most effective way to mitigate climate change. The challenge lies in how such an issue, involving so many opposed stakeholders, can be tackled through an objective lense. It is also crucial to determine who the experts are and where their legitimacy comes from to build such a discourse. As prevalently spread, the idea that numbers are neutral is the backbone of the measurement methodology dominance. But can we really put a price on the pollution created by our economic system? And should we? Our research starts by deconstructing the process that has led to pricing carbon. The objective is to understand how scientific discoveries regarding climate change became framed by the economic interpretation as an urgent and global issue. We first examine the expertise that put the quantification of carbon damages at the heart of policymaking. After having questioned the objectivity of quantification methods, we review how these methods have shifted from a scientific point of view to an economic-oriented analysis of carbon impacts, notably thanks to the work of economists such as William Nordhaus and Nicholas Stern. This is mainly explained by the market relationship of Man as a "rational actor" to Nature as a "Common Pool Resource" system. As these resources are limited, putting a price on the overconsumption of them (over-polluting for instance) seems to be the prefered political approach to tackle the issue. Our second chapter presents precisely how carbon has been priced by governments and scientific experts. The aim is to understand the different methods that have been developed of carbon valuation. We focus on the methodology, the actors using them, their limits and criticisms. Carbon taxes were the first mechanism implemented as a tool for climate change mitigation. However, they are not the most commonly utilized tool. Instead, cap-and-trade systems, based on a "market" for carbon emissions, are the prevalent method. Nevertheless, even if these two methods are widely used by governments, the debate on which one is better for mitigation purposes is not closed. Their effectiveness on emissions reductions and their inability to include the many dimensions of climate change, such as the effects on agriculture, health or coastal areas, have been highly criticized. That is why we have decided 4
The small estuaries represent the least recognized transitional systems and receive limited research priority and management focus among the coastal ecosystems worldwide. Though they provide numerous ecosystem services to the local inhabitants, these services are not adequately recorded compared to large estuaries and coastal systems. In this study, we evaluated the primary ecosystem services (ES) of Terekhol (TRE), a small tropical estuary along the west coast of India. The key ES identified were provisioning- fish and shellfish, crops and mangroves, raw materials (sand and salt), water for navigation; regulating-carbon sequestration, disturbance regulation and water quality control, erosion control; supporting- breeding grounds for fish and biodiversity and habitat; recreational & tourism, and cultural & information services. We used a hybrid approach to evaluate these ES using primary and secondary sources of information and scientific literature. The provisioning, regulating, supporting, recreational & tourism, and cultural & information services yielded annual economic values of US2523095.4, US58714.3 and US$35520 respectively. The perception of key stakeholders (fishers/farmers/tourism operators/researchers and students / biodiversity management committee members) were assessed and documented. Most stakeholders (75-90%) believed that TRE is essential for ferry service, raw materials, biodiversity and species, fish/shellfish, recreation, science, and education. Only 10-15% indicated that the estuary is important for the ES, such as water quality control, sediment erosion control, and carbon sequestration. This knowledge could play a vital role in policy formulation and the decision-making process to manage and conserve the ecosystem of TRE. Moreover, the study could also trigger scientific research on the ecosystem evaluation of the least recognized transitional systems of the world.
Literature shows that most of the wetlands are threatened ecosystems due to increased human activities. The proper conservation and management of the wetlands is an important step to ensure that the human population continues to benefit directly and indirectly from the wetlands, and thus the need for this study that focuses on the influence of agricultural practices and activities on the conservation of the Ol-bollosat wetland. The study adopted a descriptive survey research design, targeting 1000 households and the key informants, including the Nyumba kumi representative, Area Chief, Sub chief, KWS officers, MCA’s from Ndaragwa and Ol-jororok sub counties in Nyandarua County. Stratified random sampling was used to select two hundred and eighty seven (287) household heads as the respondents of the study. The data collection tools were interview schedules for key informants and guided questionnaires for household heads. A pilot study was carried out in Rwamuthambi wetland in Kirinyaga County. The researcher used Statistical Package for Social Scientists (SPSS version 26) to analyse data. Both descriptive and inferential statistics were used for data analysis, and the results were presented in form of bar graphs, pie charts and tables. The findings showed that agricultural activities and practices have an adverse effect on the conservation of Ol-bollosat wetland. The analysis showed that the community engaged in unsustainable agricultural practices and activities which were deleterious to the conservation of the wetland. Overgrazing on the riparian land, abstraction of water for irrigation are some of the unsustainable agricultural practices that the local community routinely engages in. The study recommends that inter-agency collaboration be enhanced so as to address the multiple challenges facing the Ol-bollosat wetland. The role of the County and National government in the management of the wetland should be enhanced, and local communities must be engaged. Further, agricultural practices and activities must be upgraded so that more cost-effective and environmentally friendly methods of irrigation are adopted. The study also recommends that further investigations be done to explore areas of meaningful community engagement in the management of the Ol-bollosat wetland.
The current paper deals with the progressive and sustainable approaches of development of tree plantation through Miyawaki method at Sabarmati Riverfront Development Corporation Limited. Miyawaki forests are one approach that has recently received a lot of attention. The Miyawaki method of reforestation, named after Japanese botanist and plant ecologist Akira Miyawaki, is a method of ecological engineering that advocates the growth of forests even in small areas by first treating the top layer of soil and then planting the local species that can thrive on their own. Ahmedabad's municipal corporation, which has Kobe, Japan as a sister city, is experimenting with this and hopes to develop such green spaces not only on land but also now on completely flowing Sabarmati River. ‘We chose this fast-growing urban forestry method, as it has reported 15% faster growth rate per year compared to the other reforestation methods,’ said Dr. Asif Memon, General Manager (Parks and Garden), and Sabarmati Riverfront Development, who is overseeing the reforestation initiatives. Moreover, for maintenance, all that a Miyawaki forest requires is good water supply and weeding for two years. Thereafter, it will be self-sustaining, need no external support. The current study gathers the strategic objectives for developing tree plantations using the Miyawaki method, as well as the benefits to nature and other ecosystems.
Indigenous knowledge refers to the understandings, skills and philosophies developed by societies with long histories of interaction
with their natural surroundings (UNESCO, 2018; IPCC, 2019a). Local knowledge refers to the understandings and skills developed by
individuals and populations, specific to the places where they live (UNESCO, 2018; IPCC, 2019a). Indigenous knowledge and local
knowledge are inherently valuable but have only recently begun to be appreciated and in western scientific assessment processes in their
own right (Ford et al., 2016). In the past these often endangered ways of knowing have been suppressed or attacked (Mustonen, 2014).
Yet these knowledge systems represent a range of cultural practices, wisdom, traditions and ways of knowing the world that provide
accurate and useful climate change information, observations and solutions (very high confidence) (Table Cross-Chapter Box INDIG.1).
Rooted in their own contextual and relative embedded locations, some of these knowledges represent unbroken engagement with the
earth, nature and weather for many tens of thousands of years, with an understanding of the ecosystem and climatic changes over
longer-term timescales that is held both as knowledge by Indigenous Peoples and local peoples, as well as in the archaeological record
(Barnhardt and Angayuqaq, 2005; UNESCO, 2018).
This Cross-Chapter Box highlights the intersecting issues of gender, climate change adaptation, climate justice and transformative
pathways. A gender perspective does not centre only on women or men but examines structures, processes and relationships of power
between and among groups of men and women and how gender, particularly in its non-binary form, intersects with other social
categories such as race, class, socioeconomic status, nationality or education to create multi-dimensional inequalities
Blue carbon has been recently recognized worldwide as one of the various carbon reduction measures. There are three types of blue carbon in the South Korean Ocean: salt marsh, seagrass meadow, and tidal flat. This article strives to assess the economic value of blue carbon judged by the public by the use of a choice experiment (CE). Chosen attributes for the CE application were the area of salt marsh, the area of seagrass meadow, and the number of tidal flats. A CE survey of 1000 households was successfully implemented throughout the country. All the estimates for the three attributes and price held statistical significance. The yearly household economic values arising from one unit (1 km²) increase in each attribute were computed to be KRW 202 (USD 0.18), KRW 238 (USD 0.21), and KRW 331 (USD 0.30), respectively. This quantitative information can be used in calculating the economic benefits of a blue carbon restoration project and performing cost-benefits analysis on the project. The results demonstrate that for all three types of blue carbon, the economic benefit of restoring 1 km² of each blue carbon type was at least five times greater than the cost of restoring it. In other words, the restoration of blue carbon is socially profitable.
The present investigation was carried out to assess the physico-chemical characteristics of Mangrove region in the Kavi, Dhuvara and Somnath for a period of ten (10) months. Surface water samples were collected from the chosen sampling stations at fortnightly intervals and analyzed to provide baseline information on the physico-chemical characteristics of these coastal biotopes. During the study period, variations observed in different water quality parameters of mangrove stations respectively. The present study would be helpful in assessing the changes in water quality that might happen in long run due to port development, regular port activities, industries that are in operation in and around the port area, shrimp farming etc.
On 26 December 2004, the eastern part of the Indian Ocean was hit by a tremendous tsunami created by a submarine earthquake of magnitude 9.1 on the Richter scale off the west coast of Sumatra. The tsunami also reached the western part of the Indian Ocean, including the coastal areas of eastern Africa. Along the coast of Kenya (Figs 1, 2) it resulted in a sudden increase in water level comparable to a high tide situation. This rather limited consequence was partly due to the great distance to the epicentre of the earthquake, and partly due to the low tide at the time of the impact. Hence the reefs that fringe two thirds of the coastline reduced the energy of the tsunami waves and protected the coastal areas. During the spring of 2005, staff members from the Geological Survey of Denmark and Greenland (GEUS) carried out field work related to the project KenSea - development of a sensitivity atlas for coastal areas of Kenya (Tychsen 2006; Tychsen et al. 2006). Local fishermen and authorities often asked what would have been the effect if the tsunami had hit the coastal area during a high tide, and to answer the question GEUS and the Kenya Marine and Fisheries Research Institute (KMFRI) initiated a tsunami damage projection project. The aim was to provide an important tool for contingency planning by national and local authorities in the implementation of a national early warning strategy. The tsunami damage projection project used the database of coastal resources - KenSeaBase - that was developed during the KenSea project. The topographical maps of Kenya at a scale of 1: 50 000 have 20 m contour lines, which is insufficient for the tsunami run-up simulation modelling undertaken by the new tsunami project. Therefore new sets of aerial photographs were obtained, and new photogrammetric maps with contour lines with an equidistance of 1 m were drawn for a 6 - 8 km broad coastal zone. The tsunami modelling is based on the assumption that the height of a future tsunami wave would be comparable with the one that reached the coastal area of Kenya in December 2004. Based on the regional geology of the Indian Ocean, it appears that the epicentre for a possible future earthquake that could lead to a new tsunami would most likely be situated in the eastern part of the ocean. Furthermore, based on a seismological assessment it has been estimated that the largest tsunami that can be expected to reach eastern Africa would have a 50% larger amplitude than the 2004 tsunami. It was therefore decided to carry out the simulation modelling with a tsunami wave similar to that of the 2004 event, but with the wave reaching the coast at the highest astronomical tide (scenario 1) and a worst case with a 50% larger amplitude (scenario 2: Fig. 3). The 2004 tsunami documented that the coastal belt of mangrove swamps provided some protection to the coastline by reducing the energy of the tsunami. Hence we included in this study a scenario 3 (Fig. 4), in which the mangrove areas along the coastline were removed. Maps for the three scenarios have been produced and show the areas that would be flooded, the degree of flooding, and the distribution of buildings such as schools and hospitals in the flooded areas. In addition, the force and velocity of the wave were calculated (COWI 2006).
Mangroves are often reported as nursery grounds for fish. Fish may enter mangrovesin order to avoid predators, but may not need to do so if turbidity provides a sufficient predatorrefuge outside the forest. This study assessed the effects of turbidity in the field and laboratoryon mangrove fish community structure and behaviour. The extent to which fish penetrate intomangroves has received little attention. This study also looked at differences in fish communitystructure at mangrove sites near (6m) and far (200m) from the mangrove/sea boundary.Twelve field samples were taken at approximately monthly intervals from replicate 25m2landward and seaward plots, in a Sonneratia alba stand at Gazi Bay, Kenya. A total of 25 speciesof fish were caught, 15 in seaward plots and 13 in landward ones. Mean abundance for all plots andsampling times was 2.15 (equivalent to 0.09 m-2). Seaward plots had a total mean abundance morethan twice that of landward plots (2.75 ± 1.9 S.D. vs. 1.23 ± 0.33 S.D. respectively). There wasno relationship between abundance and turbidity. Laboratory experiments showed no significantchanges in behaviour of three common species in response to turbidity. The low density of fishrecorded concurs with previous work, and probably reflects conditions in Gazi Bay as a whole,rather than unusual features of the mangrove environment there.
Payments for marine and coastal ecosystem services (PCMES) offer a way of “capturing” ecosystem service values and internalising them into people’s land and resource use decisions. They respond to, and attempt to remedy, the persistent undervaluation of ecosystem services in the policies, prices and markets that drive economic activities. In turn, ecosystem valuation is a key step in the process of identifying opportunities for PCMES and justifying them to stakeholders. A major reason for valuing ecosystem services is to “make the case” for PCMES: to provide hard, and much-needed, evidence to public and private decision-makers of the benefits arising from marine and coastal ecosystem services and the costs that are incurred to provide them. From an economic perspective, ecosystems should be treated as a key part of coastal infrastructure — as a stock of facilities, services and equipment which are needed for the economy and society to function. The chapter contends that effective PCMES schemes require a shift in the way in which development and conservation trade-offs are calculated by decision-makers — moving from a paradigm which overlooks the value of natural ecosystems to approaches which count and invest in them as an economic part of coastal infrastructure. It is illustrated with examples from tropical Asia, and uses case studies of the Muthurajawela coastal wetland and the Maha Oya estuary in Sri Lanka to demonstrate how ecosystem valuation can be used to identify and communicate the opportunities and gains associated with PCMES.
The iCoast project 'understanding the fiscal and regulatory mechanisms necessary to achieve CCD in the coastal zone' is funded by the Climate & Development Knowledge Network (CDKN) and carried out by Edinburgh Napier University, LTS International, Birmingham University, Ruhuna University in Sri Lanka and Kenya Marine and Fisheries Institute, in collaboration with Ecometrica. This document is an output from a project funded by the UK Department for International Development (DFID) and the Netherlands Directorate-General for International Cooperation (DGIS) for the benefit of developing countries. However, the views expressed and information contained in it are not necessarily those of or endorsed by DFID, DGIS or the entities managing the delivery of the Climate and Development Knowledge Network, which can accept no responsibility or liability for such views, completeness or accuracy of the information or for any reliance placed on them.
The importance of mangrove forests in carbon sequestration and coastal protection has been widely acknowledged. Large-scale damage of these forests, caused by hurricanes or clear felling, can enhance vulnerability to erosion, subsidence and rapid carbon losses. However, it is unclear how small-scale logging might impact on mangrove functions and services. We experimentally investigated the impact of small-scale tree removal on surface elevation and carbon dynamics in a mangrove forest at Gazi bay, Kenya. The trees in five plots of a Rhizophora mucronata (Lam.) forest were first girdled and then cut. Another set of five plots at the same site served as controls. Treatment induced significant, rapid subsidence (−32.1±8.4 mm yr−1 compared with surface elevation changes of +4.2±1.4 mm yr−1 in controls). Subsidence in treated plots was likely due to collapse and decomposition of dying roots and sediment compaction as evidenced from increased sediment bulk density. Sediment effluxes of CO2 and CH4 increased significantly, especially their heterotrophic component, suggesting enhanced organic matter decomposition. Estimates of total excess fluxes from treated compared with control plots were 25.3±7.4 tCO2 ha−1 yr−1 (using surface carbon efflux) and 35.6±76.9 tCO2 ha−1 yr−1 (using surface elevation losses and sediment properties). Whilst such losses might not be permanent (provided cut areas recover), observed rapid subsidence and enhanced decomposition of soil sediment organic matter caused by small-scale harvesting offers important lessons for mangrove management. In particular mangrove managers need to carefully consider the trade-offs between extracting mangrove wood and losing other mangrove services , particularly shoreline stabilization, coastal protection and carbon storage.
The ratios of stable isotopes 18O:16O and 13C:12C were measured in otolith carbon taken from nine species of fishes caught within mangroves and on the reef at Gazi Bay, Kenya. Before analysis, otoliths were divided into ‘larval’‘post-larval’ and ‘adult’ sections using a drill. Fishes were putatively classified as ‘mangrove residents’‘offshore residents’ or ‘migrants’ on the basis of information from the literature, and depending on where they were caught (mangroves only, offshore only or both mangroves and offshore) in the present study. Eight of the species exhibited an increase in otolith 13C:12C with age, but this was significant only in the two migrant species Lethrinus harak and Lutjanus fulviflammus. There were no consistent patterns in 18O:16O with age, or between migrants and non-migrants. These results suggest that comparing absolute values of otolith oxygen and carbon isotope signatures between fish species is not a useful way of determining migration patterns at this site, because of species-specific differences in carbon metabolism and insufficiently steep gradients in temperature and salinity. Changes in carbon isotope signatures between life stages within a species, however, do hold promise as migration tracers.
Mangroves are ecologically and economically important forests of the tropics. They are highly productive ecosystems with rates of primary production equal to those of tropical humid evergreen forests and coral reefs. Although mangroves occupy only 0.5% of the global coastal area, they contribute 10-15% (24 Tg C y(-1)) to coastal sediment carbon storage and export 10-11% of the particulate terrestrial carbon to the ocean. Their disproportionate contribution to carbon sequestration is now perceived as a means for conservation and restoration and a way to help ameliorate greenhouse gas emissions. Of immediate concern are potential carbon losses to deforestation (90-970 Tg C y(-1)) that are greater than these ecosystems' rates of carbon storage. Large reservoirs of dissolved inorganic carbon in deep soils, pumped via subsurface pathways to adjacent waterways, are a large loss of carbon, at a potential rate up to 40% of annual primary production. Patterns of carbon allocation and rates of carbon flux in mangrove forests are nearly identical to those of other tropical forests.
a b s t r a c t Mangroves are globally important carbon stores and as such have potential for inclusion in future forest-based climate change mitigation strategies such as Reduced Emissions from Deforestation and Degrada-tion (REDD+). Participation in REDD+ will require developing countries to produce robust estimates of forest above-ground biomass (AGB) accompanied by an appropriate measure of uncertainty. Final esti-mates of AGB should account for known sources of uncertainty (measurement and predictive) particu-larly when estimating AGB at large spatial scales. In this study, mixed-effects models were used to account for variability in the allometric relationship of Kenyan mangroves due to species and site effects. A generic biomass equation for Kenyan mangroves was produced in addition to a set of species-site spe-cific equations. The generic equation has potential for broad application as it can be used to predict the AGB of new trees where there is no pre-existing knowledge of the specific species-site allometric rela-tionship: the most commonly encountered scenario in practical biomass studies. Predictions of AGB using the mixed-effects model showed good correspondence with the original observed values of AGB although displayed a poorer fit at higher AGB values, suggesting caution in extrapolation. A strong relationship was found between the observed and predicted values of AGB using an independent validation dataset from the Zambezi Delta, Mozambique (R 2 = 0.96, p = < 0.001). The simulation based approach to uncertainty propagation employed in the current study produced estimates of AGB at different spatial scales (tree – landscape level) accompanied by a realistic measure of the total uncertainty. Estimates of mangrove AGB in Kenya are presented at the plot, regional and landscape level accompanied by 95% prediction intervals. The 95% prediction intervals for landscape level estimates of total AGB stocks suggest that between 5.4 and 7.2 megatonnes of AGB is currently held in Kenyan mangrove forests. Ó 2013 The Authors. Published by Elsevier B.V. All rights reserved.
The increasing worldwide trend in disasters, which will be aggravated by global environmental change (including climate change), urges us to implement new approaches to hazard mitigation, as well as exposure and vulnerability reduction. We are, however, faced with hard choices about hazard mitigation: should we continue to build dikes and walls to protect ourselves against floods and coastal hazards – though we have seen the limits of these – or should we consider alternative, ecosystem-based solutions? Ecosystem management is a well-tested solution to sustainable development that is being revisited because of its inherent “win-win” and “no-regrets” appeal to address rising disaster and climate change issues. It is one of the few approaches that can impact all elements of the disaster risk equation – mitigating hazards, reducing exposure, reducing vulnerabilities and increasing the resilience of exposed communities. Yet, the uptake of ecosystem-based approaches for disaster risk reduction (DRR) is slow despite some very good examples of success stories. Reasons for this are multiple: ecosystem management is rarely considered as part of the portfolio of DRR solutions because the environmental and disaster management communities typically work independently from each other; its contribution to DRR is highly undervalued compared to engineered solutions and thus not attributed appropriate budget allocations; finally, there are poor science-policy interactions on ecosystem-based DRR, which have led to unclear and sometimes contradictory scientific information on the role of ecosystems for DRR.
The aim of this book is to provide an overview of knowledge and practice in this multi-disciplinary field of ecosystem management and DRR. It contains 17 chapters written by 57 professionals from the science and practice communities around the world, representing state-of-the-art knowledge, practices and perspectives on the topic. It will serve as a basis to encourage and further develop dialogues between scientists, practitioners, policymakers and development planners.
The composition and abundance of teleosts in an estuarine mangrove bay, sampled with a beach seine-net, are described. Site 1, at the mouth of a small river, was fringed by mangroves and had a silty substratum; Site 2 was also mangrove-fringed but had a sandy substratum and seagrass patches; Site 3 had a muddy sand substratum and also supported seagrasses. In total, 128 teleost species belonging to 50 families were identified in samples collected over 12 months. Gerreidae, Atherinidae and Clupeidae accounted for 78.5% of the total number of fish. Juveniles were found for 63% of the species. Of the fish species found, 44% were species associated with coral reefs. The mean numbers of species were similar at all sites, despite the differences in substratum type. Ecological diversity indices were higher, and fish density and biomass were lower, in the mangrove-fringed silt site than in the seagrass sites. Mean number of species was highest in February and June. Most families of commercial fish sought by fishers in the area were represented in the samples.
Gazi Bay, Kenya, covers an area of 18 km 2 , and its mangroves are degraded. We present a quantitative and qualitative evaluation of the degradation of vegetation structure and dynamics of mangrove communities over a period of 25 yr, using aerial photography in a geographical informa- tion system (GIS), combined with ground-truth data for different vegetation layers, and with faunal and environmental factors. Retrospective analysis and understanding of current practices were aided by interviews with Gazi village elders and by field observations of mangrove tree stumps. GIS-based vegetation maps were combined with data obtained using the point-centred quarter method (PCQM), an accuracy analysis was performed, and forestry parameters were derived from the resul- tant PCQM data. In addition to general human-induced degradation of vegetation structure and floristic composition of the seaward mangrove zone, a particular sandy beach is expanding at the expense of mangrove, whereas the back mangrove zone has undergone minor changes. Aerial photographs of 1992 and current field data show an apparent zonation of 6 different monospecific or mixed mangrove communities, with a high importance of Rhizophora mucronata in each community and each vegetation layer. Retrospective vegetation structure was combined with correspondence analyses on the PCQM data derived for adult, young and juvenile trees in order to make predictions. Present dynamics initiated by anthropogenic degradation of mangroves continues, even though human impact has diminished. We predict that under a 'no impact scenario', the sandy ridge will continue to expand, that this will speed up under a 'mangrove cutting scenario', and that a scenario altering the complex topography will lead to a major re-organisation of the mangrove and terrestrial vegetation structure.
Aim Our scientific understanding of the extent and distribution of mangrove forests of the world is inadequate. The available global mangrove databases, com-piled using disparate geospatial data sources and national statistics, need to be improved. Here, we mapped the status and distributions of global mangroves using recently available Global Land Survey (GLS) data and the Landsat archive. Methods We interpreted approximately 1000 Landsat scenes using hybrid super-vised and unsupervised digital image classification techniques. Each image was normalized for variation in solar angle and earth–sun distance by converting the digital number values to the top-of-the-atmosphere reflectance. Ground truth data and existing maps and databases were used to select training samples and also for iterative labelling. Results were validated using existing GIS data and the published literature to map 'true mangroves' . Results The total area of mangroves in the year 2000 was 137,760 km 2 in 118 countries and territories in the tropical and subtropical regions of the world. Approximately 75% of world's mangroves are found in just 15 countries, and only 6.9% are protected under the existing protected areas network (IUCN I-IV). Our study confirms earlier findings that the biogeographic distribution of mangroves is generally confined to the tropical and subtropical regions and the largest percentage of mangroves is found between 5° N and 5° S latitude. Main conclusions We report that the remaining area of mangrove forest in the world is less than previously thought. Our estimate is 12.3% smaller than the most recent estimate by the Food and Agriculture Organization (FAO) of the United Nations. We present the most comprehensive, globally consistent and highest reso-lution (30 m) global mangrove database ever created. We developed and used better mapping techniques and data sources and mapped mangroves with better spatial and thematic details than previous studies.
Forest structure and productivity was investigated in a 12-year-old Rhizophora mucronata Lam. plantation at Gazi Bay, Kenya. Sampling was carried out in 22, 10 m  10 m quadrats laid along belt transects perpendicular to the waterline. Within each quadrat all trees with stem diameter greater than 2.5 cm were identified, position marked and counted. Vegetation measurements included tree height (m), canopy cover (%) and stem diameter measured at 1.3 m above the ground (D 130); from which were derived basal area (m 2 /ha); stand density (stems/ha) and biomass (t/ha). Information regarding composition and distribution of juveniles was derived using linear regeneration sampling (LRS). The replanted forest had a stand density of 5132 stems/ha; with a mean canopy height and stem diameter of 8.4 AE 1.1 m (range: 3.0–11.0 m) and 6.2 AE 1.87 cm (range: 2.5– 12.4 cm), respectively. The total juvenile density was 4886 saplings per hectare; 78.6% of which constituted the parental canopy. The standing biomass for the 12-year-old R. mucronata plantation was 106.7 AE 24.0 t/ha, giving a biomass accumulation rate of 8.9 t/(ha year).
c1 Correspondence: Dr Patrik Rönnbäck e-mail: pat@ecology.su.se
The coastal ecosystem is essential to life on our planet and supports the livelihood of people living and depending on coastal resources. The abundance of good quality coastal resources is fundamental to all marine biological processes and supports living resources. Moreover it is essential for the maintenance of biodiversity and ecosystems, in addition to primary and secondary production functions that support human needs. Valuation studies of coastal resources will considerably increase our knowledge of the value of ecosystems. Their usefulness has often been undermined due to undervaluation, the main reason for coastal resources destruction. Despite a global consensus on the need to implement stakeholder management approaches and on Millennium Development Goals for food security, poverty reduction and preservation of ecosystems, the reality in most countries is a competition between different groups and sectors for access to coastal ecosystem services. The real value of wetlands plays a major role in this predicament. A variety of innovative methods of economics are usually applied in the valuation of cultural and provisioning services in coastal ecosystem under the concept of total value. The basic premise underlying all these economic valuation techniques is the individual's willingness to pay (WTP) or willingness to accept (WTA). The contingent valuation method (CVM) uses a direct stated preference approach to valuing an environment good or service in that it asks people through surveys or experiments what they are WTP for the good or WTA for the loss of the good. A demand curve can be traced using the bid values estimated in a CVM study which is particularly attractive because it can estimate values where market do not exist or where market substitutes cannot be found. Choice experiment (CE) is becoming an increasingly popular stated preference technique in valuing coastal resources. CE is considered to be both an evolution of and an alternative to CVM and both methods use stated preference approaches and both are usually based on random utility theory. Two studies in Europe and Asia using CVM and CE approaches for valuing cultural and provisioning ecosystem services are highlighted in this paper. There is an urgent need for research to determine the status of regulating services and how the value can actually be captured and incorporated in decision making process in ecosystem management.
The global decline in estuarine and coastal ecosystems (ECEs) is affecting a number of critical benefits, or ecosystem services. We review the main ecological services across a variety of ECEs, including marshes, mangroves, nearshore coral reefs, seagrass beds, and sand beaches and dunes. Where possible, we indicate estimates of the key economic values arising from these services, and discuss how the natural variability of ECEs impacts their benefits, the synergistic relationships of ECEs across seascapes, and management implications. Although reliable valuation estimates are beginning to emerge for the key services of some ECEs, such as coral reefs, salt marshes, and mangroves, many of the important benefits of seagrass beds and sand dunes and beaches have not been assessed properly. Even for coral reefs, marshes, and mangroves, important ecological services have yet to be valued reliably, such as cross-ecosystem nutrient transfer (coral reefs), erosion control (marshes), and pollution control (mangroves). An important issue for valuing certain ECE services, such as coastal protection and habitat–fishery linkages, is that the ecological functions underlying these services vary spatially and temporally. Allowing for the connectivity between ECE habitats also may have important implications for assessing the ecological functions underlying key ecosystems services, such coastal protection, control of erosion, and habitat–fishery linkages. Finally, we conclude by suggesting an action plan for protecting and/or enhancing the immediate and longer-term values of ECE services. Because the connectivity of ECEs across land–sea gradients also influences the provision of certain ecosystem services, management of the entire seascape will be necessary to preserve such synergistic effects. Other key elements of an action plan include further ecological and economic collaborative research on valuing ECE services, improving institutional and legal frameworks for management, controlling and regulating destructive economic activities, and developing ecological restoration options.
This article reviews the historic evolution of qualitative scenario storylines and the various methods used in their development and application in environmental change assessment. The scenario method largely emerged from military strategy and war planning, with the techniques being adopted and advanced further by the business sector. Scenario storylines became widely applied to environmental problems from the 1970s and since then a number of new studies have been developed at both global and regional scales. Many different methods are used in scenario storyline development although most examples applied to environmental change assessment are exploratory and defined through a matrix logic that reflects different dimensions of environmental change drivers. This article discusses several development techniques for scenario storylines, provides examples of existing scenario storylines, discusses the differences between them, and highlights a number of limitations in the current scenario storyline development methods. The credibility, legitimacy, and saliency of future scenario storylines are discussed with respect to personal beliefs, the equifinality of alternative development pathways, the validation and uncertainty of assumptions, stakeholder engagement in visions development, and participatory methods. Copyright © 2010 John Wiley & Sons, Ltd.
This article is categorized under: Assessing Impacts of Climate Change > Scenario Development and Application
Integrated Assessment of Climate Change > Integrated Scenario Development
Aim Our scientific understanding of the extent and distribution of mangrove forests of the world is inadequate. The available global mangrove databases, compiled using disparate geospatial data sources and national statistics, need to be improved. Here, we mapped the status and distributions of global mangroves using recently available Global Land Survey (GLS) data and the Landsat archive.
Methods We interpreted approximately 1000 Landsat scenes using hybrid supervised and unsupervised digital image classification techniques. Each image was normalized for variation in solar angle and earth–sun distance by converting the digital number values to the top-of-the-atmosphere reflectance. Ground truth data and existing maps and databases were used to select training samples and also for iterative labelling. Results were validated using existing GIS data and the published literature to map ‘true mangroves’.
Results The total area of mangroves in the year 2000 was 137,760 km2 in 118 countries and territories in the tropical and subtropical regions of the world. Approximately 75% of world's mangroves are found in just 15 countries, and only 6.9% are protected under the existing protected areas network (IUCN I-IV). Our study confirms earlier findings that the biogeographic distribution of mangroves is generally confined to the tropical and subtropical regions and the largest percentage of mangroves is found between 5° N and 5° S latitude.
Main conclusions We report that the remaining area of mangrove forest in the world is less than previously thought. Our estimate is 12.3% smaller than the most recent estimate by the Food and Agriculture Organization (FAO) of the United Nations. We present the most comprehensive, globally consistent and highest resolution (30 m) global mangrove database ever created. We developed and used better mapping techniques and data sources and mapped mangroves with better spatial and thematic details than previous studies.
Statistical data shows that the increase in disasters due to natural hazards over the past 20years has, for the most part,
been caused by meteorological and hydrological events. This increase has been largely assigned to climate change [Centre for
Research on the Epidemiology of Disasters (CRED), 2010, http://www.emdat.be/Database/Trends/trends.html], that is, with climate-related hazards being major triggers for the majority of disasters. Consequently, there is obvious
concern about how a changing climate will exacerbate the situation in the future (McBean and Ajibade in Curr Opin Environ
Sustain 1:179–186, 2009). However, the attribution of a single hazard event or specific losses to climate change is still difficult, if not impossible,
due to the complexity of factors that generate disaster losses. Disaster risk is a product of the interaction of the hazard
(event) and the vulnerability conditions of the society or elements exposed. As a result, the need for a systematic linkage
between disaster risk reduction (DRR) and climate change adaptation (CCA) to advance sustainable development, and finally
human security is being discussed within the ongoing climate change negotiations as well as within the disaster risk community,
for example, in the framework of the Intergovernmental Panel on Climate Change special report on ‘Managing the risks of extreme
events and disasters to advance climate change adaptation’. However, crucial differences between DRR and CCA exist that have
widely limited or hampered their integration in practice. A review of existing literature on the topic and current national
and local adaptation strategies, as well as 38 expert interviews conducted between April and May 2009, have led the authors
to hypothesise that most of these differences and challenges can be categorised with respect to different spatial and temporal
scales, the knowledge base, and norm systems. This paper examines the reasons for the practical barriers when linking CCA
and DRR according to these three aspects. Finally, we outline recommendations and measures that need to be adopted in order
to overcome existing barriers. In addition, quality criteria are formulated that should be applied in order to constantly
monitor and evaluate adaptation strategies designed to simultaneously meet DRR requirements and vice versa.
KeywordsDisaster risk reduction-Climate change adaptation-Conflict-Risk management
The structure and regeneration patterns of the peri-urban mangrove vegetation of Mombasa at Tudor creek were studied along belt transects at two forest sites of Kombeni and Tsalu. Based on the species importance values, the dominant mangrove species were Rhizophora mucronata Lam. (Rhizophoraceae) and Avicennia marina (Forssk.) Vierh. (Avicenniaceae). Lumnitzera racemosa Willd., reported in an earlier floristic survey, was not encountered. Tree density varied from 1,264 trees ha–1 at Kombeni to 1,301 trees ha–1 at Tsalu and mean tree height was higher at the former site compared to the latter. The size-class structure at both localities showed the numerical dominance of small trees over larger trees. The spatial distribution pattern of adults and juveniles varied greatly between sites and showed a close to uniform pattern (Morisita’s Index I
δ ≪ 1) for adult trees, but a tendency to clustered distribution (I
δ ≫ 1) for juveniles. The present paper shows that unmanaged but exploited peri-urban mangroves are structurally stressed, having enlarged canopy gaps that are characterised by spatial and temporal site heterogeneity that influences regeneration, implying longer periods for canopy closure. Diversifying uses of mangrove products and establishing reserves as no cut zones with regulated harvesting will minimise canopy gap sizes, and promote conservation practices. The proposed management strategy shall boost the ecosystem resilience to both anthropogenic and natural stressors expected in the peri-urban setting in the long run.
Mangrove reforestation projects often suffer from low sapling survival, especially after transplanting saplings from nurseries
to reforestation areas. This may be due to the sediment conditions at the target site, the planting strategy or failure to
re-establish ecosystem processes. We examined experimentally the influence of environmental context, species richness and
identity, sapling height and position on sapling survival and environmental variables linked to ecosystem functioning at deforested
sites in Gazi Bay, Kenya. At site 1, a high shore location, 32 plots (36m2) were planted with 8 treatments: all possible combinations of Avicennia marina, Bruguiera gymnorrhiza, and Ceriops tagal and an unplanted control (total: 3390 saplings; 4 plots/treatment). At site 2, a low shore location, the influence of sapling
height, sapling position and sediment depth were tested by planting with 697 Sonneratia alba in a single monospecific plot (341m2). After ∼2years, there were significant differences in survival among the three species at site 1 with Bruguiera gymnorrhiza recording the lowest survival rate (29%). Survival was correlated with salinity (a strong effect) and height above chart
datum (a weaker effect) at site 1. Sapling position did not significantly affect survival at either site. There was thus no
evidence that early survival of transplanted saplings is influenced by the species mix in which they are grown, or by their
position in the plot. Rather the tolerance of individual species to salinity was the key to their survival at the high tidal
site. Species mix also had no significant effects on environmental variables in the plots. The former presence of a species
at a site does not guarantee it will succeed there again if environmental degradation has exceeded species’ tolerance.
Estimation of total biomass in woody ecosystems is important because of its relevance to nutrient turnover and the potential to store carbon. Most work on mangrove biomass, particularly in the Western Indian Ocean Region, has concentrated on the above-ground component; comparatively little is known on below-ground biomass. The current study was conducted at Gazi bay on the southern coast of Kenya. The objective was to determine the below-ground biomass of three species of mangrove, Rhizophora mucronata Lamarck, Avicennia marina (Forsk.) Vierh and Sonneratia alba J. Smith, in natural and replanted stands. The effects of distance from the tree base and of soil depth on root biomass and size distributions were also studied using coring. Live below-ground biomass (mean ± S.E.) ranged from 7.5 ± 0.4 t/ha to 35.8 ± 1.1 t/ha, 48.4 ± 0.7 t/ha to 75.5 ± 2.0 t/ha and 39.1 ± 0.7 t/ha to 43.7 ± 1.7 t/ha for R. mucronata, S. alba and A. marina, respectively, depending on the age of the stand. Including dead roots produced total biomass values of 34.9 ± 1.8–111.5 ± 5.6 t/ha, 78.9 ± 3.3–121.5 ± 7.3 t/ha and 49.4 ± 1.1–84.7 ± 5.4 t/ha for R. mucronata, S. alba and A. marina. These values imply carbon contents of live roots ranging between 3.8 ± 0.2 C t/ha and 17.9 ± 0.6 C t/ha, 24.2 ± 0.4 C t/ha and 37.7 ± 1.0 C t/ha and 19.5 ± 0.4 C t/ha and 21.9 ± 0.9 C t/ha for R. mucronata, S. alba and A. marina stands, respectively, and 17.4 ± 0.9 C t/ha and 55.7 ± 2.8 C t/ha, 39.4 ± 1.7 C t/ha and 60.7 ± 3.6 C t/ha and 24.7 ± 0.6 C t/ha and 42.4 ± 2.9 C t/ha for R. mucronata, S. alba and A. marina stands, respectively if dead roots are included. Stand densities were 4650 ± 177 stems/ha, 3800 ± 212 stems/ha and 3567 ± 398 stems/ha for R. mucronata 6-year old, 12-year-old and natural stands respectively. Mean stem diameter, and basal area were highest in the 12-year-old plantation while below-ground root biomass increased with age. Stand density for S. alba, was highest in the 12-year-old plantation (7900 ± 141 stems/ha) while the 9-year-old stand had trees with the largest diameter (7.7 ± 0.9 cm). Below-ground biomass was highest in the 12-year old (75.5 ± 2.0 t/ha) and lowest in the natural stand (48.4 ± 0.7 t/ha). Stand density for A. marina was highest in the 12-year-old plantation (4300 ± 919 stems/ha) while mean stem diameter (7.9 ± 0.7 cm) and basal area (16.2 ± 2.1 m2/ha) were highest in the natural stand. Below-ground biomass in the 12-year-old (43.7 ± 1.7 t/ha) and natural stands (39.1 ± 0.7 t/ha) was similar. Root densities decreased with soil depth and with distance from the base of trees for all species and stands. Fine roots (diameter <5 mm) constituted between 24% and 45% of the total stand live root biomass. The information generated is important in establishing the total biomass and thus the potential amount of carbon sequestered by mangroves in the study area.
Protected areas are used to sustain biodiversity and ecosystem services. However, protected areas can create tradeoffs spatially and temporally among ecosystem services, which can affect the welfare of dependent local communities. This study examines the effect of a protected area on the tradeoff between two extractive ecosystem services from mangrove forests: cutting mangroves (fuelwood) and harvesting the shrimp and fish that thrive if mangroves are not cut. We demonstrate the effect in the context of Saadani National Park (SANAPA) in Tanzania, where enforcement of prohibition of mangrove harvesting was strengthened to preserve biodiversity. Remote sensing data of mangrove cover over time are integrated with georeferenced household survey data in an econometric framework to identify the causal effect of mangrove protection on income components directly linked to mangrove ecosystem services. Our findings suggest that many households experienced an immediate loss in the consumption of mangrove firewood, with the loss most prevalent in richer households. However, all wealth classes appear to benefit from long-term sustainability gains in shrimping and fishing that result from mangrove protection. On average, we find that a 10% increase in the mangrove cover within SANAPA boundaries in a 5-km(2) radius of the subvillage increases shrimping income by approximately twofold. The creation of SANAPA shifted the future trajectory of the area from one in which mangroves were experiencing uncontrolled cutting to one in which mangrove conservation is providing gains in income for the local villages as a result of the preservation of nursery habitat and biodiversity.
Mangroves form important ecosystems in Kenya's coastal areas. They produce goods and services that are of environmental, ecological and economic importance to human society. However, mangroves are under continuing pressure from anthropogenic disturbances. A particular concern has been the clearing of mangrove areas to reclaim land for other uses such as aquaculture, salt manufacture, agriculture and housing. About 10 000 ha of mangrove areas have been cleared for salt manufacture between Ngomeni and Karawa, while in Lamu, close to 100 ha of mangrove forest was killed by dredged-up sediment that was deposited during the construction of the Mokowe sea jet. 100 ha of mangrove area have been converted for aquaculture at Ngomeni. At Gazi Bay, about 100 ha of mangrove forests was cleared for fuelwood and in Makupa Creek, Mombasa, 10 ha of mangroves died due to oil pollution. The total area lost is therefore 10 310 ha which represents about 20% of the total mangrove forest.
In this paper, deforestation, conversion of mangrove areas for other land uses and pollution of mangrove swamps on the Kenyan coast are discussed and a call for sustainable use, and the government policies that will enable this, is made.
Mangrove forests are one of the world's most threatened tropical ecosystems with global loss exceeding 35% (ref. 1). Juvenile coral reef fish often inhabit mangroves, but the importance of these nurseries to reef fish population dynamics has not been quantified. Indeed, mangroves might be expected to have negligible influence on reef fish communities: juvenile fish can inhabit alternative habitats and fish populations may be regulated by other limiting factors such as larval supply or fishing. Here we show that mangroves are unexpectedly important, serving as an intermediate nursery habitat that may increase the survivorship of young fish. Mangroves in the Caribbean strongly influence the community structure of fish on neighbouring coral reefs. In addition, the biomass of several commercially important species is more than doubled when adult habitat is connected to mangroves. The largest herbivorous fish in the Atlantic, Scarus guacamaia, has a functional dependency on mangroves and has suffered local extinction after mangrove removal. Current rates of mangrove deforestation are likely to have severe deleterious consequences for the ecosystem function, fisheries productivity and resilience of reefs. Conservation efforts should protect connected corridors of mangroves, seagrass beds and coral reefs.
Despite great recent progress, hunger and poverty remain widespread and agriculturally driven environmental damage is widely prevalent. The idea of agricultural sustainability centers on the need to develop technologies and practices that do not have adverse effects on environmental goods and services, and that lead to improvements in food productivity. Here we show the extent to which 286 recent interventions in 57 poor countries covering 37 M ha (3% of the cultivated area in developing countries) have increased productivity on 12.6 M farms while improving the supply of critical environmental services. The average crop yield increase was 79% (geometric mean 64%). All crops showed water use efficiency gains, with the highest improvement in rainfed crops. Potential carbon sequestered amounted to an average of 0.35 t C ha(-1) y(-1). If a quarter of the total area under these farming systems adopted sustainability enhancing practices, we estimate global sequestration could be 0.1 Gt C y(-1). Of projects with pesticide data, 77% resulted in a decline in pesticide use by 71% while yields grew by 42%. Although it is uncertain whether these approaches can meet future food needs, there are grounds for cautious optimism, particularly as poor farm households benefit more from their adoption.
A common assumption is that ecosystem services respond linearly to changes in habitat size. This assumption leads frequently to an "all or none" choice of either preserving coastal habitats or converting them to human use. However, our survey of wave attenuation data from field studies of mangroves, salt marshes, seagrass beds, nearshore coral reefs, and sand dunes reveals that these relationships are rarely linear. By incorporating nonlinear wave attenuation in estimating coastal protection values of mangroves in Thailand, we show that the optimal land use option may instead be the integration of development and conservation consistent with ecosystem-based management goals. This result suggests that reconciling competing demands on coastal habitats should not always result in stark preservation-versus-conversion choices.
Economic analysis of mangrove reforestation is provided for a replanted Rhizophora mucronata plantation at Gazi Bay, Kenya. Major goods and services from a 12-year plantation were identified as: firewood and building poles, coastal protection, ecotourism, research and education, carbon sequestration and on-site fisheries. The net value of extractable wood products was estimated at US44.42/ha/yr in carbon sequestration to US2902.87/ha/yr. Since most of these benefits cannot be internalized, there is need for governments to promote community efforts in mangrove reforestation through finding ways of marketing ecosystem services of the replanted forests.
Complex coastal management challenges often span ecological and political boundaries, and involve competing demands from groups advocating alternative coastal management strategies. As a consequence, policy-makers require scientific evidence from across a range of disciplines. Implementing cross-disciplinary research and facilitating science-policy engagement are, however, a significant challenge in its own right. Seven recent ecologically oriented ‘big question’ exercises identified a variety of research questions potentially important for coastal and marine management. In this research, 592 coastal scientists from 91 different countries completed a survey that ranked those 20 coastally oriented research questions. There was a clear overall ordering of aggregated coastal research priorities but scientists did exhibit heterogeneity regarding priorities. Some prioritized ecological issues while others focused more on issues such as coastal resource use or global environmental change. The differences in opinion were largely disciplinary-based, highlighting the importance of, and challenges in, encouraging scientific collaboration across disciplines to support effective coastal zone management. In addition to the ranking of existing questions, scientists submitted an additional 340 potential priority research questions, thus broadening the participatory nature of the original exercises. New questions regarding coastal processes, contaminants and pollution, and monitoring were prominent. This first synthesis across ‘big question’ exercises should provide valuable insights into the diversity of scientists’ opinions and help policy makers understand potentially conflicting science advice.
Mangroves in Kenya provide a wide range of valuable services to coastal communities despite their relatively small total area. Studies at single sites show reductions in extent and quality caused by extraction for fuel wood and timber and clearance for alternative land use including saltpans, aquaculture, and tourism. Such studies suggest that Kenyan mangroves are likely to conform to the general global trend of declining area but there are no reliable recent estimates of either total mangrove extent or trends in coverage for the country. The total extent of Kenyan mangroves was estimated at four points in time (1985, 1992, 2000 and 2010) using Landsat satellite imagery. Due to its medium resolution, Landsat may underestimate mangrove areas in Kenya where relatively small, linear, coastal features occur. There is also a high frequency of clouds in the coastal areas which can cause data gaps during analysis. However comparison with aerial photographs taken in 1992 showed satisfactory levels of accuracy (87.5%) and Cohen's Kappa (0.54) validating its use in this context. These 1992 data provided an independently validated baseline from which to detect changes (fore- and hind-casted) in other periods after removing cloud coverage. We estimated total mangrove coverage in 2010 at 45,590 ha representing a loss of 18% (0.7% yr(-1)) in the 25 years between 1985 and 2010. Rates of mangrove loss for Kenya varied both spatially and temporally with variations possibly due to legislative inadequacies and differences in habitat alteration patterns. Hence freely available Landsat images proved adequate to detect changes in mangroves and revealed that Kenya shows rates of decline similar to (although slower than) global estimates.
The salt concentration of groundwater in mangrove swamps is an important parameter controlling the growth of mangrove species. Extremely high salt concentrations of groundwater in tropical salt flats are responsible for the complete absence of macrophytes. Determining groundwater salt concentrations can be a very time-consuming and laborious process if conventional techniques are used. Typically, groundwater samples must be extracted for later laboratory analysis.In this work, a simple conductivity probe has been developed which may be inserted easily to a depth of 2m into the sediment. The changes in conductivity of the sediment is due primarily to porewater salt concentration, and thus ground conductivity is useful in determining changes in groundwater salt concentrations. Using the conductivity probe, transects of sediment conductivity can be undertaken quickly.As an example of a possible application of the probe, transects of ground conductivity were taken on a mangrove swamp/saltflat system. The transects show clearly the sharp delineation in conductivity between the salt flat and mangrove swamp due to a change in groundwater salt concentrations. Horizontal and vertical salt concentration gradients of up to 50gl−1m−1and 150gl−1m−1, respectively, were found.Very sharp changes in groundwater salt concentrations at the interface between salt flats and mangroves indicate that the mangroves may be modifying the salinity of the groundwater actively.
Farmed shrimp contributed 27% of total world shrimp production in 1995 with a volume of 712 000 tonnes. Undoubtedly, the shrimp culture industry earns valuable foreign exchange for developing countries and generates jobs across the industry from fry gatherers to growers and processors. However, grave socio-economic consequences – including conversion, expropriation and privatization of mangroves and other lands; salinization of water and soil; decline in food security; marginalization of coastal communities, unemployment and urban migration; and social conflicts – have followed in the wake of, shrimp farm development in the Philippines and other tropical countries.
The paper focuses on mangrove ecosystems: the valuation and cost-benefit analysis of their goods and services, and the mangrove-offshore fisheries connection. Research gaps in these areas and the need to internalize the ecological and socio-economic costs (‘externalities’) of shrimp farming are highlighted. Other recommendations include mangrove conservation and rehabilitation, enforcement of existing legislation, and introduction of environment-friendly aquaculture within the broader framework of community-based, integrated coastal area management, e.g. the traditional, extensive polyculture ponds in Indonesia.
Deforestation of mangroves is of global concern given their importance for carbon storage, biogeochemical cycling and the provision of other ecosystem services, but the links between rates of loss and potential drivers or risk factors are rarely evaluated. Here we identified key drivers of mangrove loss in Kenya and compared two different approaches to predicting risk. Risk factors tested included various possible predictors of anthropogenic deforestation, related to population, suitability for land use change and accessibility. Two approaches were taken to modelling risk; a quantitative model and a qualitative categorical ranking approach. A quantitative model linking rates of loss to risk factors was constructed based on generalized least squares regression and using mangrove loss data from 1992-2000. Population density, soil type, and proximity to roads were the most important predictors. In order to validate this model it was used to generate a map of losses of Kenyan mangroves predicted to have occurred between 2000 and 2010. The qualitative categorical model was constructed using data from the same selection of variables, with the coincidence of different risk factors in particular mangrove areas used in an additive manner to create a relative risk index which was then mapped. Quantitative predictions of loss were significantly correlated with the actual loss of mangroves between 2000 and 2010 and the categorical risk index values were also highly correlated with the quantitative predictions. Hence in this case the relatively simple categorical modelling approach was of similar predictive value to the more complex quantitative model of mangrove deforestation. The advantages and disadvantages of each approach are discussed, and the implications for mangroves are outlined. © 2013 Blackwell Publishing Ltd.
By using a seine net, fish samples were taken from the nonestuarine Chwaka Bay (Zanzibar, Tanzania) from the mangroves, mud/sand flats and seagrass beds. Sampling was done twice per month between November 2001 and October 2002. In total, 150 fish species belonging to 55 families were identified. Diversity (H′) ranged from 1.9 in mud/sand flats to 3.4 within the Chwaka seagrass beds. Mean density of fishes was significantly higher in the mangrove creeks than in any other habitat (mean = 238.7 ind./1000 m2). Highest, but non-significantly different mean biomasses were recorded in the mangrove creeks (1.7 kg/1000 m2) and in the Marumbi seagrass beds (1.6 kg/1000 m2). The mangrove channel had the lowest biomass (0.6 kg/1000 m2). A high overlap in species composition (as high as 93.4% similarity) was found for adjoining habitats (i.e. mangrove creeks and mangrove channel), while habitats that were far apart showed low overlap (6.6% similarity for the Marumbi seagrass beds and mangrove creeks). On average, 58.4 and 63.2% in terms of abundance and biomass, respectively, of the fish assemblage of Chwaka Bay were of commercial fishery importance. Thus, Chwaka Bay appears to be an important juvenile habitat for various commercially important fish species.
Mangrove ecosystems are threatened by climate change. We review the state of knowledge of mangrove vulnerability and responses to predicted climate change and consider adaptation options. Based on available evidence, of all the climate change outcomes, relative sea-level rise may be the greatest threat to mangroves. Most mangrove sediment surface elevations are not keeping pace with sea-level rise, although longer term studies from a larger number of regions are needed. Rising sea-level will have the greatest impact on mangroves experiencing net lowering in sediment elevation, where there is limited area for landward migration. The Pacific Islands mangroves have been demonstrated to be at high risk of substantial reductions. There is less certainty over other climate change outcomes and mangrove responses. More research is needed on assessment methods and standard indicators of change in response to effects from climate change, while regional monitoring networks are needed to observe these responses to enable educated adaptation. Adaptation measures can offset anticipated mangrove losses and improve resistance and resilience to climate change. Coastal planning can adapt to facilitate mangrove migration with sea-level rise. Management of activities within the catchment that affect long-term trends in the mangrove sediment elevation, better management of other stressors on mangroves, rehabilitation of degraded mangrove areas, and increases in systems of strategically designed protected area networks that include mangroves and functionally linked ecosystems through representation, replication and refugia, are additional adaptation options.
Many species of coral reef fish undertake ontogenetic migrations between seagrass beds, mangroves, and coral reefs. A recent study from the Caribbean found that the availability of mangrove nursery habitat had a striking impact on the community structure and biomass of reef fish in their adult, coral reef habitat. The biomass of several species more than doubled when the reefs were connected to rich mangrove resources (defined as having at least 70 km of fringing Rhizophora mangle within a region of 200 km2). Here, the results of this large-scale empirical study are translated into a series of algorithms for use in natural resource management planning. Four algorithms are described that identify (i) the relative importance of mangrove nursery sites, (ii) the connectivity of individual reefs to mangrove nurseries, (iii) areas of nursery habitat that have an unusually large importance to specific reefs, and (iv) priority sites for mangrove reforestation projects. The algorithms generate a connectivity matrix among mangroves and coral reefs that facilitates the identification of connected corridors of habitats within a dynamic planning environment (e.g., reserve selection algorithms).
The juvenile fish community associated with natural, degraded and replanted Sonneratia alba mangroves in Gazi Bay was sampled during the South East and North East monsoons between April 2002 and June 2003. A total of 1800 individuals belonging to 49 taxa and 34 families were collected from the intertidal forest using stake nets. Fish abundance ranged from 0.93 ± 0.20 ind. m−2 (SEM02) to 1.16 ± 0.18 ind. m−2 (SEM03) between seasons and between 0.54 ± 0.07 ind. m−2 and 1.64 ± 0.33 ind. m−2 for individual sites across seasons. Five taxa accounted for approximately 70% of the total fish abundance, with Gobidae and Gerres oyena dominating. ANOSIM revealed seasonal differences in fish species composition and abundance (p = 0.01) due to fluctuating abundances of primarily Terapon sp. and Thryssa sp. The majority (65%) of fishes were reef associates, which implies a tight coupling between mangroves and coral reefs. The high proportion (75%) of commercial species indicates that fringing S. alba mangroves of Gazi Bay are important in sustaining coastal fisheries in the area. The fact that the replanted mangroves of Gazi Bay harbor a significant number of commercially important species as juveniles suggest their function as nursery habitats for nekton may well have been restored. This study is original in quantitatively evaluating the use of replanted intertidal mangroves by juvenile fish in the West Indian Ocean; a topic poorly studied worldwide to date.
The fish communities of mangrove and cleared sites were investigated in Gazi Bay, Kenya. Five forested sites were compared with paired sites that had been cleared of mangroves by human activity. Forested sites included plantations and natural stands of Sonneratia alba and natural Rhizophora mucronata stands. Two methods of stake netting were used to take quantitative samples; method one used a single 100-m-long, 18-mm mesh net, method two used paired 24-m-long, 1-mm mesh nets—samples were taken during seven different months in 2002. Mean abundances of fish found in mangrove and cleared sites, respectively, were 0.004 m−2 and 0.014 m−2 (method 1) and 0.21 m−2 and 0.25 m−2 (method 2). Thirty species were sampled, 12 of which were found exclusively in mangrove habitats and 10 of which were limited to cleared sites. The most abundant species in mangrove plots was Atherina afra (although it was only found in two, large catches); the most abundant in cleared plots was Gerres oyena (found frequently). Mean abundance (using data pooled for all sites) was significantly higher in cleared, compared with forested, sites, and multivariate analysis showed significantly different community structures in the two habitat types. There was large variation in catch rates between dates and sites, with one forested site recording no catches at all. These results do not support the predator refuge hypothesis (which predicts higher abundance of juvenile fish inside mangroves). The low abundance of fish recorded in the mangrove sites may have been due to site-specific factors determining fish abundance within mangrove forests, to the sampling techniques used or to relatively high turbidities at these sites.
Mangroves are disappearing rapidly worldwide despite their well documented biodiversity and the ecosystem services they provide. Failure to link ecological processes and their societal benefits has favored highly destructive aquaculture and tourism developments that threaten mangroves and result in costly “externalities.” Specifically, the potentially irreparable damage to fisheries because of mangrove loss has been belittled and is greatly underestimated. Here, we show that, in the Gulf of California, fisheries landings are positively related to the local abundance of mangroves and, in particular, to the productive area in the mangrove–water fringe that is used as nursery and/or feeding grounds by many commercial species. Mangrove-related fish and crab species account for 32% of the small-scale fisheries landings in the region. The annual economic median value of these fisheries is US $37,500 per hectare of mangrove fringe, falling within the higher end of values previously calculated worldwide for all mangrove services together. The ten-year discounted value of one hectare of fringe is >300 times the official cost set by the Mexican government. The destruction of mangroves has a strong economic impact on local fishing communities and on food production in the region. Our valuation of the services provided by mangroves may prove useful in making appropriate decisions for a more efficient and sustainable use of wetlands.
• discounted values
• economic benefits
• ecosystem services
• small-scale fisheries
• Rhizophora fringe forest
Payments for Ecosystem Services (PES) economically reward resource managers for the provision of ecosystem services and are thus characterised by (i) an ecological function subject to trade; (ii) the establishment of a standard unit of exchange; (iii) and supply, demand and intermediation flows between those who sell and buy ecosystem services. This paper departs from the term commodity fetishism, broadly understood as the masking of the social relationships underlying the process of production, to illuminate three invisibilities in the commodification of ecosystem services. Firstly, we argue that narrowing down the complexity of ecosystems to a single service has serious technical difficulties and ethical implications on the way we relate to and perceive nature. Secondly, the commodification of ecosystem services denies the multiplicity of values which can be attributed to these services, since it requires that a single exchange-value is adopted for trading. Finally, we suggest that the process of production, exchange and consumption of ecosystem services is characterised by power asymmetries which may contribute to reproducing rather than addressing existing inequalities in the access to natural resources and services.
Mangrove ecosystems are a very important category of wetland systems that shelter coastlines and estuaries. Mangroves, especially in the tropics, are rich in flora and fauna. Their major environmental services include storm protection, shore stabilization, and control of soil erosion and flooding. They are also a biomass export and a nursery ground for marine life. In Thailand, however, mangroves rapidly disappear at the alarming rate of approximately 38,909 rai (6,225 ha) per year (Table 1.1). One of the major causes of mangrove clearance is the conversion of mangrove areas into the intensive shrimp farms which have become a very popular business venture, especially in the South of Thailand (CORIN 1995). Mangrove swamps are targets for shrimp farming because the areas are flooded with brackish water which become potential areas for aquaculture (Hassanai 1993). In fact, culture of banana shrimps ( ) and greasy shrimps ( ) has been practised for more than 50 years. In traditional methods, mangroves are only partially cleared but the intensive culture of black tiger shrimps ( ) requires full conversion of mangrove areas. This type of shrimp culture started as early as 1974. However, it was in 1985 when Japan's increasing demand for shrimps pushed up the price to $100 per kilogram, and intensive shrimp farming boomed (Bantoon 1994).
Mangroves are ecologically important coastal wetland systems that are under severe threat globally. In Thailand, the main cause of mangrove conversion is shrimp farming, which is a major source of export income for the country. However, local communities benefit from many direct and indirect uses of mangrove ecosystems and may have a strong incentive to protect these areas, which puts them into direct confrontation with shrimp farm operators and, by proxy, government authorities. The article examines whether or not the full conversion of mangroves into commercial shrimp farms is worthwhile once the key environmental impacts are taken into account. The estimated economic value of mangrove forests to a local community is in the range of 35,92l per hectare. This estimate includes the value to local communities of direct use of wood and other resources collected from the mangroves as well as additional external benefits in terms of off-shore fishery linkages, and coastline protection from shrimp farms. The results indicate that, although shrimp farming creates enormous private benefits, it is not so economically viable once the externalities generated by mangrove destruction and water pollution are included. There is also an incentive for local communities to protect mangroves, which in turn implies that the rights of local people to guard and protect this resource should be formally recognized and enforced by law.
Economic Analysis of Mangrove Forests : a Case Study in Gazi Bay
- J Tychsen
- O Geertz-Hansen
- F Schjøth
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UNEP, 2011. Economic Analysis of Mangrove Forests : a Case Study in Gazi Bay,
Kenya. United Nations Environment Programme, Nairobi.