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... The latter interpretation of the diversity-stability relationship represents part of the broader biodiversity-ecosystem function relationship, which hypothesizes that biodiversity increases ecological processes through functional complementarity or niche partitioning (McCann, 2000;Thibaut et al., 2012). One proposed mechanism by which biodiversity can increase stability is the portfolio effect (Schindler et al., 2010(Schindler et al., , 2015, which arises from different responses of functionally similar species to perturbations (Elmqvist et al., 2003;Laliberté et al., 2010). In this case, biodiversity is hypothesized to reduce variability in rates of ecological functions despite changes in community composition, which assumes lower stability in community composition. ...
... where different species show complementary responses to disturbance, has been posited as a reason why diverse assemblages facing disturbance can promote functioning, leading to changing communities but stable aggregate functioning (Elmqvist et al., 2003). While there is strong community turnover (i.e., low compositional stability) in diverse cryptobenthic fish communities in our study, there appears to be either insufficient functional redundancy or low response diversity, ultimately preventing diversity from bolstering functioning (in our case, the recovery of standing stock biomass). ...
Article
Aim: As anthropogenic stressors on the biosphere intensify, understanding how communities respond to disturbances is critical. Biodiversity is often thought to promote the stability of communities over time and enhance ecosystem functioning. However, results have been inconsistent, and the multifaceted linkages among diversity, stability and functioning under acute disturbances remain poorly understood. We experimentally tested the responses of marine fish communities to disturbance (i.e., acute habitat loss) across a diversity gradient spanning 35 degrees of latitude in the western Atlantic Ocean to assess the diversity-stability relationship and the interplay between diversity, stability, and fish biomass recovery (as a proxy for function) in marine fish communities. Location: Western Atlantic Ocean [Maine, Massachusetts, North Carolina, Florida (USA), Belize and Panama]. Time period: 2016-2017. Major taxa studied: Small, bottom-dwelling ('cryptobenthic') fishes. Methods: We experimentally tested the response of marine fish communities to disturbance across a diversity gradient on human-made dock pilings. We holistically sampled cryptobenthic fish communities, then we imposed a severe disturbance by removing all benthic epifauna. We then compared the community stability, defined as the constancy in community composition, on disturbed and undisturbed pilings after one year. Results: Diversity showed a negative effect on community stability at both the regional (across docks) and local (within docks) scales. Similarly, local diversity was negatively correlated with ecosystem function. These effects are exacerbated by the habitat loss imposed via our experimental treatment. Main conclusions: Our results suggest that habitat loss may reshuffle diverse, tropical communities more intensively than species-poor, temperate communities, which impacts biomass recovery, our proxy of functioning. Contrary to ecological theory, in small-bodied, benthos-associated vertebrate communities, biodiversity may neither promote stability nor functioning, suggesting that human disturbances may be particularly impactful in tropical, high-diversity ecosystems.
... Different potential strategies must be implemented to value this human-plant interaction under the Payment for Ecosystem Services framework: (i) conservation of forest stands beyond the minimum legally required; (ii) the valuation of the pinhão supply chain; (iii) the maintenance of pinhão ethnovarieties; (iv) the mensuration of the ecosystem services provided by remnant areas; (v) the restoration of degraded areas; (vi) food security for vulnerable social groups (see Tagliari et intraspeci c and functional diversity is boosted, and, consequently, promote resilience and adaptive capacity to climate change, besides creating positive feedback between TEK holders and the entire socioecological system (Elmqvist et al. 2003;Holland et al. 2017;Tagliari et al. 2021a). Also, by preserving araucaria remnants via TEK holders we nd a win-win strategy because there is a possibility to engage more local groups in environmental governance and shorten the distance of actions that degrade the surrounding environment thanks to restrictive measures that usually exclude local groups (Tam and Chan 2017; Orellana and Vanclay 2018;Zechini et al. 2018;Tagliari et al. 2021a and Sustainable Use Protected Areas (green); black dots represent the occurrence of 97 ethnoecological interviews in this study. ...
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Socioecological systems (SES) hinge on human groups and ecosystems, promoting interdependence and resilience to environmental disturbances. Climate change effects propagate from organism to biomes, likely influencing SES. In southern Brazil, Araucaria Forest is a typical SES due to the historical interaction between humans and biodiversity. We thus aimed to evaluate empirically and theoretically how climate change could disrupt this system by interviewing 97 smallholders and assessing their Traditional Ecological Knowledge (TEK). We evaluated and measured: (i) socioeconomic impact of araucaria’s nut-like seed ( pinhão ) trade; (ii) ethnoecological knowledge about climate change; and (iii) generated an ecosystem services network. We projected these empiric data with a projected loss of 50-70% of the Araucaria Forest due to climate change to quantify the risks of the potential disruption of this socioecological system. We found evidence that to avoid the disruption of the Araucaria Forests is paramount to value TEK holders, safeguard the historical socioecological interaction, and promote non-mutually exclusive measures in an integrative response to maintain the Araucaria Forests resilient to future disturbances.
... Changes in trait diversity are important as well as changes in mean values, because the assemblage-level diversity in how populations respond to drivers of change underpins ecosystem stability and resilience under drivers of change (Diaz & Cabido, 2001;Elmqvist et al., 2003). For instance, both among-and within-population diversity in adaptive life history traits in salmon tend to stabilize temporal variation in overall abundance and hence harvest (Schindler et al., 2013). ...
... An ecosystem's resistance to change is a key component of its resilience. FLR actions such as implementing an adaptive management system and re-establishing natural stream flow, removing invasive species, and providing migration/dispersal corridors between protected areas contribute to resilience by maintaining diversity, continuously measuring the biophysical dimensions of the landscape, and periodically assessing vulnerability to climate change and evolving gene pools over time (Elmqvist et al. 2003;Walker et al. 2004a, b). Factors such as ecologically effective population sizes, genetic and functional diversity, densities of highly interactive species, ecological community tolerance to extreme events, and microtopographic diversity are also important considerations in restoration strategies aimed at maintaining or restoring resilience and encouraging open access to and sharing of information and knowledge (Gilman et al. 2010). ...
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Forest landscape restoration (FLR) is the process where vegetation is recovering in terms of its forest traits, ecosystem functionality, climate change mitigation, building up human livelihoods, and well-being in deforested and degraded forest landscapes by promoting accelerated forest regrowth. Several countries within the Global Partnership of FLR have made ambitious pledges to promote FLR globally and to restore at least 350 million ha of degraded and deforested lands by 2030 worldwide. FLR accountability has been limited to the schematic quantification of how much the land area in the forest has been restored and how many trees have been replanted for conservation purposes. Natural regeneration, old-growth forests, and mixed-species plantations of different types of species are some of the FLR strategies. Monitoring the outcome of complex forest restoration efforts requires appropriate methods and sophisticated tools. The logical procedures are by distinguishing the different forest cover types across different forest landscapes and second by identifying their respective values to ecosystem services and biodiversity conservation. Canopy structural attributes are one of the most important parameters that can act both, distinguishing the forest cover types and indicator to the forest respective values. Traditional assessments rely heavily on field-based inventory, which is cost-prohibitive and difficult to track a million hectares scale progress. Light detection and ranging (LiDAR) remote sensing has emerged as a great alternative to monitoring forest structure, function, and composition. With the ability to penetrate the forest canopy it allows an accurate measurement of structural canopy parameters along with the vertical profile. This paper will review the trends of FLR and the use of LiDAR remote sensing technology to monitor forest restoration outcomes towards achieving sustainable forest management practices.KeywordsForest landscape restorationLiDARForest typeForest structureStructural attributes
... In primary production, increasing diversity secures the harvest and promotes both short-and long-term resilience (Degani et al. 2019). Different reactions to change are important for resilience-for example, in different ways to respond to drought (Elmqvist et al. 2003;Folke et al. 2004). Differences in yield responses increase resilience to different and unexpected weather conditions (Hakala et al. 2012;Kahiluoto et al. 2014Kahiluoto et al. , 2019 and provide adaptation options for climate change (Howden et al. 2007). ...
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Unlabelled: Food systems are increasingly exposed to disruptions and shocks, and they are projected to increase in the future. Most recently, the war in Ukraine and Covid-19 pandemic has increased concerns about the ability to secure the availability of food at stable prices. This article presents a food system resilience framework to promote a national foresight system to better prepare for shocks and disruptions. Our study identified four key elements of resilience: system thinking through science and communication; redundancy of activities and networks; diversity of production and partners; and buffering strategies. Three national means to enhance resilience in the Finnish food system included domestic protein crop production, renewable energy production, and job creation measures. Primary production was perceived as the cornerstone for food system resilience, and the shocks and disruptions that it confronts therefore call for a sufficient and diverse domestic production volume, supported by the available domestic renewable energy. A dialogue between different actors in the food system was highlighted to format a situational picture and enable a rapid response. Our study suggests that to a certain point, concentration and interdependence in the food system increase dialogue and cooperation. For critical resources, sufficient reserve stocks buffer disruptions over a short period in the event of unexpected production or market disruptions. Introducing and strengthening the identified resilience elements and means to the food system call for the preparation of a more holistic and coherent food system policy that acknowledges and emphasises resilience alongside efficiency. Supplementary information: The online version contains supplementary material available at 10.1007/s10669-022-09889-5.
... Management strategies should, in addition, pay more attention to novel approaches for increasing ecosystem resistance and resilience (e.g. Elmqvist et al. 2003;Bakker & Wilson 2004;Denslow 2007). In fact, when ERA is used for the prevention of invasions or reducing dominance of invaders, it probably is the most cost-effective method (Westbrooks & Eplee 2011;Byun & Lee 2017). ...
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The invasive Australian swamp stonecrop (Crassula helmsii) threatens species characteristic of shallow soft water lakes and pools, among others, in Europe. Anthropogenic disturbances, including restoration actions, of these ecosystems cause open niches in their littoral zones and allow C. helmsii to form dominant stands, especially under nutrient enrichment. Eradication of this invasive alien, amphibious and clonal plant is, however, difficult and costly once a large population has established. For this reason, we here explore an ecosystem resilience approach (ERA) to control this invasive alien species. This approach includes supressing the species by facilitating the occurrence and expansion of native vegetation. This requires a set‐back of C. helmsii’s abundance by actively reducing its biomass, and the rehabilitation of optimal environmental conditions for native species. Our ERA study in four nature areas reveals that the introduction of native species makes the ecosystem more resilient against alien invasions, as shown by a lower abundance of this invasive plant species. Therefore, we state that ERA can effectively be applied in practice to decrease the invasibility of ecosystems by C. helmsii. Effectiveness, costs and benefits, and recommendations for application in practice are discussed. Overall, we argue that incorporating ERA in nature‐ and water management will provide sustainable solutions in terms of biodiversity as well as more cost‐effective applications for invasive alien species prevention and control. This article is protected by copyright. All rights reserved.
... Drought stress can cause a series of reductions in morphological and physiological functional traits (e.g., plant height, specific leaf area, length of roots, leaf water potential, and photosynthetic capacity), which may finally lead to a reduction in productivity (Cenzano et al., 2013;Wellstein et al., 2017). Response diversity, describing the variation of responses to environmental change among species in a particular community, maybe a key determinant of ecosystem stability and functionality (Elmqvist et al., 2003;Mori et al., 2013). For instance, perennial caespitose grasses and rhizomatous grasses showed different growth response strategies to drought, as the CG of rhizomatous grasses declined with increasing water stress intensity while caespitose grasses displayed little CG with strong drought resistance (Zhang et al., 2018). ...
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Grasslands are structurally and functionally controlled by water availability. Ongoing global change is threatening the sustainability of grassland ecosystems through chronic alterations in climate patterns and resource availability, as well as by the increasing frequency and intensity of anthropogenic perturbations. Compared with many studies on how grassland ecosystems respond during drought, there are far fewer studies focused on grassland dynamics after drought. Compensatory growth, as the ability of plants to offset the adverse effects of environmental or anthropogenic perturbations, is a common phenomenon in grassland. However, compensatory growth induced by drought and its underlying mechanism across grasslands remains not clear. In this review, we provide examples of analogous compensatory growth from different grassland types across drought characteristics (intensity, timing, and duration) and explain the effect of resource availability on compensatory growth and their underlying mechanisms. Based on our review of the literature, a hypothetic framework for integrating plant, root, and microbial responses is also proposed to increase our understanding of compensatory growth after drought. This research will advance our understanding of the mechanisms of grassland ecosystem functioning in response to climate change.
... This work is possible; however, it requires mathematical care and must recognise the importance of employing a numerically stable metric (Segarra and Ribeiro 2016) when analysing a weighted, hierarchical graph such as the USAH. Stable betweenness centrality (as just one example) can identify changes at the tangible levels to further explore resilience concepts such as redundancy and diversity (see Elmqvist et al. 2003;Beevers et al. 2021). This could help understand how a system absorbs a shock and how adaptation could be supported in the future (McClymont et al., in review). ...
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To add to the engineer’s toolkit for the twenty-first century challenges, we demonstrate a novel systems model for understanding urban impacts. The model captures interdependencies between different interconnected systems (or sectors, e.g. recreational services or public healthcare) in cities, from the tangible (e.g. resources such as roads) to the more intangible (e.g. outcomes such as the sustainable economy). The model is hazard-agnostic in that it can be modified to capture the impacts of different shocks on tangible parts of the system and how these cascade through to more abstract and high-level city tasks and outcomes. This paper demonstrates three hypothetical scenarios (a flood, drought, and pandemic) and their impacts on a generic UK city. Using the network analysis, impacts can be tracked and interpreted to help prioritise requirements for resilience-building. We propose this new tool be taken up and tested by others working to address global challenges such as the Sustainable Development Goals and grappling with the interconnectedness of urban systems.
... Groundwater is an indispensable water resource in arid inland regions (Elmqvist et al., 2003;Shamsudduha, 2013;Nampak et al., 2014;Chinnasamy et al., 2018). Not only is groundwater essential for all life, but it also performs valuable ecosystem services. ...
Article
Study region Hotan River Basin, an arid inland river basin, Northwest China. Study focus A method for assessing the spatial distribution of groundwater resilience is constructed by combining the Dempster-Shafer theory model and spatial analysis techniques. The groundwater performance indicator CRS and resilience indicator pi are calculated to present groundwater resilience. Using the Dempster-Shafer theory model to mine the data, nine groundwater conditioning factors are selected as evidential layers of the model, and the mathematical relationships between the resilience indicators and groundwater conditioning factors are established through evidence integration; Ultimately, a groundwater resilience spatial distribution map is generated, and the performance of the map is explored based on the CRS and pi values. New hydrological insights for the region The constructed assessment method based on this study reliably and effectively predicts the regional groundwater resilience. Validation of the groundwater resilience prediction map with pi indicates that this indicator outperforms the CRS. The areas with high groundwater resilience are mainly concentrated in the upstream oasis irrigation area and the downstream river channel. The groundwater resilience (pi) zonation map is divided into five categories: very low (Bel of 0–0.072), low (0.072–0.171), moderate (0.171–0.458), moderate high (0.458–0.786), and high (>0.786). The results can provide a scientific basis for groundwater safety and management in the Hotan River Basin.
... Traits provide a basis to maximize resilience and stability in restored systems by maximizing the diversity of response traits while building redundancy in the effect traits (Elmqvist et al. 2003;Shackelford et al. 2013). For example, in a rangeland system, ecosystem functions were maintained following heavy grazing through species that had similar effect traits, providing similar functions, but differed in their response to grazing compared to the dominant species (Walker et al. 1999). ...
Article
Restoration ecologists devote considerable time and resources to understanding the role of functional traits in community assembly and ecosystem functioning. However, while functional traits show promise in supporting restoration practice in some circumstances, traits are not often explicitly considered by practitioners. Here we highlight four reasons that are preventing the use of traits in restoration, ranging from different restoration targets and frameworks to practical considerations around species selection, databases, plant stock availability, and measurement approaches. We provide actions that can be taken by researchers, practitioners, plant stock producers, and policy makers to better incorporate functional traits in restoration practice and show how traits can complement existing practices to achieve both traditional/taxonomic and functional restoration targets. We hope to guide critical partnerships, missing research, and immediate actions to leverage the value of traits at all stages in the restoration process. This article is protected by copyright. All rights reserved.
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Mass extinctions shape the history of life and can be used to inform understanding of the current biodiversity crisis. In this paper, a general introduction is provided to the methods used to investigate the ecosystem effects of mass extinctions (Part I) and to explore major patterns and outstanding research questions in the field (Part II). The five largest mass extinctions of the Phanerozoic had profoundly different effects on the structure and function of ecosystems, although the causes of these differences are currently unclear. Outstanding questions and knowledge gaps are identified that need to be addressed if the fossil record is to be used as a means of informing the dynamics of future biodiversity loss and ecosystem change.
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Large wood is inherently mobile in naturally functioning river corridors, yet river management commonly introduces wood that is anchored to limit hazards. Wood that is periodically mobilized is important for: replacing stationary large wood that performs diverse physical and ecological functions; contributing to the disturbance regime of the river corridor; diversifying wood decay states; dispersing organisms and propagules; providing refugia during floodplain inundation and in mobile‐bed channels; dissipating flow energy; and supplying wood to downstream environments including lakes, coastlines, the open ocean, and the deep sea. We briefly review what is known about large wood mobility in river corridors and suggest priorities for ongoing research and river management, including: structural designs that can pass mobile wood; enhancing piece diversity of introduced wood that is anchored in place; quantifying wood mobilization and transport characteristics in natural and managed river corridors; and enhancing documentation of the benefits of wood mobility.
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Financial advisers recommend a diverse portfolio to respond to market fluctuations across sectors. Similarly, nature has evolved a diverse portfolio of species to maintain ecosystem function amid environmental fluctuations. In urban planning, public health, transport and communications, food production, and other domains, however, this feature often seems ignored. As we enter an era of unprecedented turbulence at the planetary level, we argue that ample responses to this new reality — that is, response diversity — can no longer be taken for granted and must be actively designed and managed. We describe here what response diversity is, how it is expressed and how it can be enhanced and lost. A varied repertoire of responses helps manage fluctuations, as in markets. This Perspective argues that society needs to strengthen the diversity of options for responding to disruptions, exploring how this response diversity is expressed, how it can be built and lost, and what we can do to promote it.
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Differences in the life history pathways (LHPs) of juvenile animals are often associated with differences in demographic rates in later life stages. For migratory animals, different LHPs often result in animals from the same population occupying distinct habitats subjected to different environmental drivers. Understanding how demographic rates differ among animals expressing different LHPs may reveal fitness trade‐offs that drive the expression of alternative LHPs and enable better prediction of population dynamics in a changing environment. To understand how demographic outcomes and their relationships with environmental variables differ among animals with different LHPs, we analyzed a long‐term (2006–2021) mark–recapture dataset for Chinook salmon (Oncorhynchus tshawytscha) from the Wenatchee River, Washington, USA. Distinct LHPs represented in this population include either remaining in the natal stream until emigrating to the ocean as a 1‐year‐old (natal‐reach rearing) or emigrating from the natal stream and rearing in downstream habitats for several months before completing the emigration to the ocean as a 1‐year‐old (downstream rearing). We found that downstream‐rearing fish emigrated to the ocean 19 days earlier on average and returned as adults from the ocean at higher rates. We detected a positive correlation between rate of return from the ocean by downstream‐rearing fish and coastal upwelling in their spring of outmigration, whereas for natal‐reach‐rearing fish we detected a positive correlation with sea surface temperature during their first marine summer. Different responses to environmental variability should lead to asynchrony in adult abundance among juvenile LHPs. A higher proportion of downstream‐rearing fish returned at younger ages compared with natal‐reach‐rearing fish, which contributed to variability in age at reproduction and greater mixing across generations. Our results demonstrate how diversity in juvenile LHPs is associated with heterogeneity in demographic rates during subsequent life stages, which can in turn affect variance in aggregate population abundance and response to environmental change. Our findings underscore the importance of considering life history diversity in demographic analyses and provide insights into the effects of life history diversity on population dynamics and trade‐offs that contribute to the maintenance of life history diversity.
Purpose This study aims to the development of the scale of supply chain performance measures (SCPMs), food supply chain resilience (FSCS) and sustainable corporate performance (SCP) in small- and medium-sized enterprises (SMEs) in an emerging market. Based on this purpose, the study examines the relationships between SCPMs and SCP by exploring the mediating role of FSCS in emerging markets. Design/methodology/approach Based on a comprehensive literature review on the SCPMs, FSCS and SCP, the author evaluates the nexus of these constructs on disruptions during the COVID-19 pandemic emergency in an emerging market. The article follows a quantitative approach. A total of 567 valid responses from managers at senior and middle levels were received and used for data analysis. The Smart PLS version 3.3.2 was employed to analyse Structural Equation Modelling (SEM) to investigate the relationships between constructs and latent variables. Findings This study provides some theoretical contributions to expand the extant literature on the domain of SCPMs. First, the findings determine that multidimensional measures of flexibility, diversity, agility, inventory efficiency, redundancy and robustness are appropriate for measuring food SC performance in disruptions during the COVID-19 emergency. Besides, this study enriches the existing literature on SC disruption by providing extensive empirical evidence on SCPMs in disruptions during the COVID-19 emergency. Finally, this research provides an integrated empirical model that explores the link between the identified food SCPMs to FSCS and SCP. Originality/value The contributions may be of interest to business practitioners, business leaders and academics. In addition, this study provides empirical evidence to demonstrate that food SC performance, as measured by these measures, is strongly related to the firm's food supply chain resilience. This is the novel contribution of this study to the current literature on food SC management. Furthermore, this study provides further empirical evidence demonstrating the partial mediating role of the firm's food supply chain resilience in the nexus between food SC performance and SCP. The unique contribution of this study is an extension of the body of knowledge of SC management literature from a comprehensive approach by providing a proven set of performance measures of SC management to which it can drive SC resilience and SCP for food manufacturing SMEs in an emerging economy that hardly found in the current literature.
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Animal-mediated pollination is a vital ecosystem service to crops and wild plants, and long-term stability of plant–pollinator interactions is therefore crucial for maintaining plant biodiversity and food security. However, it is unknown how the composition of pollinators and the structure of pollinator interactions have changed across longer time spans relevant to examining responses to human activities such as climate change. We resampled an historical dataset of plant–pollinator interactions across several orders of pollinating insects in a subarctic location in Finland that has already experienced substantial climate warming but little land use change. Our results reveal a dramatic turnover in pollinator species and rewiring of plant–pollinator interactions, with only 7% of the interactions shared across time points. The relative abundance of moth and hoverfly pollinators declined between time points, whereas muscoid flies, a group for which little is known regarding conservation status and responses to climate, became more common. Specialist pollinators disproportionately declined, leading to a decrease in network-level specialization, which could have harmful consequences for pollination services. Our results exemplify the changes in plant–pollinator networks that might be expected in other regions as climate change progresses.
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Wildfire disturbances can profoundly impact many aspects of both ecosystem functioning and resilience. This study proposes a satellite-based approach to assess ecosystem resilience to wildfires based on post-fire trajec-tories of four key functional dimensions of ecosystems related to carbon, water, and energy exchanges: (i) vegetation primary production; (ii) vegetation and soil water content; (iii) land surface albedo; and (iv) land surface sensible heat. For each dimension, several metrics extracted from satellite image time-series, at the short, medium and long-term, describe both resistance (the ability to withstand environmental disturbances) and recovery (the ability to pull back towards equilibrium). We used MODIS data for 2000-2018 to analyze trajectories after the 2005 wildfires in NW Iberian Peninsula. Primary production exhibited low resistance, with abrupt breaks immediately after the fire, but rapid recoveries, starting within six months after the fire and reaching stable pre-fire levels two years after. Loss of water content after the fire showed slightly higher resistance but slower and more gradual recoveries than primary production. On the other hand, albedo exhibited varying levels of resistance and recovery, with post-fire breaks often followed by increases to levels above pre-fire within the first two years, but sometimes with effects that persisted for many years. Finally, wildfire effects on sensible heat were generally more transient, with effects starting to dissipate after one year and overall rapid recoveries. Our approach was able to successfully depict key features of post-fire processes of ecosystem functioning at different timeframes. The added value of our multi-indicator approach for analyzing ecosystem resilience to wildfires was highlighted by the independence and complementarity among the proposed indicators targeting four dimensions of ecosystem functioning. We argue that such approaches can provide an enhanced characterization of ecosystem resilience to disturbances, ultimately upholding promising implications for post-fire ecosystem management and targeting different dimensions of ecosystem functioning.
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Resilience is an important attribute of incident management teams (IMTs) for managing disasters. Previous research on resilience of IMTs has focused on comparing work-as-imagined (WAI) and work-as-done (WAD) but predominantly used narrative analyses which limited comparisons between IMTs. This paper presents a novel Interaction Episode Analysis (IEA) method to identify the IMT’s WAI and WAD episodes by analyzing dynamic interactions that occur between different roles that carry out information management tasks. Observations and audio-­visual recordings of two high-fidelity IMT exercises were conducted to capture WAD episodes, and semi-structured interviews with experts elicited corresponding WAI episodes. Quantitative analyses using five interaction-based measures were conducted to detect differences of the WAD episodes between two IMTs. Next, qualitative analyses were focused on identifying reasons why such differences have occurred by comparing the gaps between WAI and WAD episodes. Some of the reasons for WAI-WAD gaps included the non-occurrence of critical interactions that were expected and occurrence of unexpected interactions between IMT members. This paper also identifies cases of preparatory, proactive, and reactive performance adjustment that characterizes IMT resilience. The IEA method shows promise for investigating how and why the gaps between WAI and WAD in IMTs occur. With the identification of these gaps, future research can be conducted to reconcile the gaps between WAI and WAD episodes, and thus enhance resilience of IMTs in future disasters.
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AimsWe studied species redundancy, functional redundancy, and community stability relationship in mountain rangelands of Northern Iran via assessing vegetation and soil resources. This study aimed to examine whether community redundancy contributes to community stability, quantify the importance of species redundancy versus functional redundancy to keep the stability of the community, and compare the relationship between these community and altitude gradient.Methods Ecological gradient determined by its environment, and disturbance factors were used to evaluate the variation in diversity, redundancy, and stability across a range of communities. We constructed a structural equation model (SEM) based on the bivariate relationships to understand the causal pathways through which the species diversity indices, functional diversity, redundancy diversity, and soil nutrients affect community stability.ResultsPositive and significant path coefficients were found for functional diversity and redundancy, species redundancy, and altitude gradient with stability. There was a significantly negative effect of functional diversity on species diversity. Species function had no effect on species redundancy.Conclusions Community stability improved at higher functional redundancy. In general, it can be concluded that the mathematical representation of functional redundancy can be an effective tool to evaluate the causal models which link plant diversity to community stability.
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Ample evidence suggests positive effects of species diversity on ecosystem functioning and services in natural and agricultural landscapes. Less obvious and even contested are the effects of such diversity on human well‐being. This state of art partly stems from methodological difficulties to evaluate and quantify these effects and imprecise conceptual frameworks. Here we propose a conceptual framework that links different aspects of diversity, particularly species and genetic richness, to ecosystem functioning, ecosystem services and disservices, and different aspects of well‐being. We review current approaches for the study of diversity–well‐being relationships and identify shortcomings and principle obstacles, mainly stemming from theoretical premises that are too imprecise. We discuss five basic methodological approaches to link diversity to well‐being: matrix models, indirect inference, Price partitioning, structural equation modelling, and environmental inference. We call for a stricter terminology with respect to the different aspects of functioning, multifunctionality and well‐being and highlight the need to evaluate each step in the different pathways from diversity to well‐being. A full understanding of ecological constraints on human well‐being requires consideration of trade‐offs in diversity effects, of contrasting perceptions of well‐being, and of ecosystem disservices. We also call for appropriate long‐term socio‐ecological research platforms to gather relevant data about ecosystem functioning and well‐being across space and time. Read the free Plain Language Summary for this article on the Journal blog. Zahlreiche Befunde deuten auf eine positive Auswirkung der Artenvielfalt auf das Funktionieren und die Leistungen von Ökosystemen in Natur‐ und Agrarlandschaften hin. Weniger offensichtlich und sogar umstritten sind die Auswirkungen einer solchen Vielfalt auf das menschliche Wohlergehen. Diese Wissenslücke ist teilweise auf methodologische Schwierigkeiten bei der Bewertung und Quantifizierung dieser Effekte und auf ungenaue konzeptionelle Rahmenbedingungen zurückzuführen. Wir schlagen hier einen konzeptionellen Rahmen vor, der verschiedene Aspekte der Vielfalt, insbesondere des Arten‐ und genetischen Reichtums, mit Ökosystemfunktionen, Ökosystemleistungen und ‐dysfunktionen und verschiedenen Aspekten des Wohlergehens verbindet. Wir beleuchten aktuelle Ansätze zur Untersuchung von Beziehungen zwischen Vielfalt und Wohlergehen und identifizieren Mängel und prinzipielle Hindernisse, die hauptsächlich auf zu ungenauen theoretischen Prämissen beruhen. Wir diskutieren fünf grundlegende methodologische Ansätze, um Diversität mit Wohlergehen zu verknüpfen: Matrixmodelle, indirekte Inferenz, Price‐Partitionierung, Pfadanalysen und Umweltinferenz. Wir plädieren für eine strengere Terminologie in Bezug auf die verschiedenen Aspekte des Funktionierens, der Multifunktionalität und des Wohlergehens und betonen die Notwendigkeit, jeden Schritt auf den verschiedenen Pfaden von der ökologischen Vielfalt zum Wohlergehen zu bewerten. Ein vollständiges Verständnis der ökologischen Einschränkungen des menschlichen Wohlergehens erfordert die Berücksichtigung der Balance bei Diversitätseffekten, von gegensätzlichen Wahrnehmungen des Wohlergehens und von Ökosystemdysfunktionen. Wir fordern auch geeignete langfristige sozio‐ökologische Forschungsplattformen, um relevante Daten über das Funktionieren von Ökosystemen in Bezug auf das menschliche Wohlergehen in Raum und Zeit zu sammeln. Množstvo dôkazov poukazuje na pozitívny vplyv diverzity na fungovanie ekosystémov a ich úlohy v prírodnej a poľnohospodárskej krajine. Menej zrejmé a dokonca otázne sú ale účinky takejto diverzity na blahobyt ľudí. Tento stav čiastočne vyplýva z metodických ťažkostí pri posudzovaní týchto účinkov a nepresných koncepčných rámcov. V tejto práci navrhujeme koncepčný rámec, ktorý spája rôzne aspekty diverzity s fungovaním ekosystémov, jej úlohou, negatívnymi účinkami a blahobytom. Preskúmame súčasné prístupy k štúdiu vzťahov medzi diverzitou a blahobytom a identifikujeme nedostatky a zásadné prekážky, ktoré vyplývajú najmä z príliš nepresných teoretických východísk. V práci rozoberáme päť základných metodologických prístupov k spojeniu diverzity a blahobytu a to: maticové modely, nepriamu inferenciu, rozdelenie podľa ceny, modelovanie štrukturálnych rovníc a inferenciu podľa prostredia. Žiadame o presnejšiu terminológiu s ohľadom na rôzne aspekty fungovania, multifunkčnosti a blahobytu a zdôrazňujeme potrebu vyhodnotiť každý krok na jednotlivých cestách od diverzity k ľudskému blahobytu. Úplné pochopenie ekologických obmedzení ľudského blahobytu si vyžaduje, aby sa zohľadňovali kompromisy v účinkoch diverzity, kontrastného vnímania blahobytu a negatívnych účinkov ekosystémových služieb. Tiež žiadame o vytvorenie vhodných dlhodobých sociálno‐ekologických výskumných platforiem, ktoré by zhromažďovali relevantné údaje o fungovaní ekosystémov a o ľudskom blahobyte v priestore a čase. Wiele dowodów wskazuje na pozytywny wpływ różnorodności na funkcjonowanie ekosystemów i ich usługi w krajobrazach naturalnych i rolniczych. Mniej oczywiste, a nawet kwestionowane są skutki takiej różnorodności dla dobrostanu człowieka. Ten stan rzeczy wynika częściowo z trudności metodologicznych w ocenie tych skutków oraz nieprecyzyjnych ram koncepcyjnych. W tym miejscu proponujemy ramy koncepcyjne, które łączą różne aspekty różnorodności z funkcjonowaniem ekosystemu, usługami i nie‐zasługami ekosystemu oraz dobrostanem. Dokonujemy przeglądu obecnych podejść do badania relacji różnorodność ‐ dobrostan i identyfikujemy braki i zasadnicze przeszkody, wynikające głównie ze zbyt nieprecyzyjnych założeń teoretycznych. Omawiamy pięć podstawowych podejść metodologicznych do powiązania różnorodności z dobrostanem: modele macierzowe, wnioskowanie pośrednie, podział Price'a, modelowanie równań strukturalnych i wnioskowanie środowiskowe. Wzywamy do wprowadzenia bardziej rygorystycznej terminologii w odniesieniu do różnych aspektów funkcjonowania, wielofunkcyjności i dobrostanu oraz podkreślamy potrzebę oceny każdego kroku na różnych ścieżkach od różnorodności do dobrostanu. Pełne zrozumienie ekologicznych ograniczeń dobrostanu człowieka wymaga uwzględnienia kompromisów w zakresie skutków różnorodności, kontrastowego postrzegania dobrostanu oraz usług ekosystemów. Wzywamy również do stworzenia odpowiednich długoterminowych platform badawczych o charakterze społeczno‐ekologicznym w celu zebrania odpowiednich danych na temat funkcjonowania ekosystemów i dobrostanu w przestrzeni i czasie. Read the free Plain Language Summary for this article on the Journal blog.
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Biodiversity management in Ecuador, and across Latin America, focuses on using protected areas for conservation purposes. However, this management strategy does not adequately consider biodiversity interactions with humans by neglecting socio-ecological systems that provide many benefits especially to indigenous and other rural peoples. This paper reviews successful examples of local applications of adaptive co-management that incorporate socio-ecological interactions and the benefits they provide to rural communities in Latin America. These examples show the potential of applying adaptive co-management to manage biodiversity and to revitalize the development of rural communities across the region.
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Animals experience seasonally changing conditions in temperate regions, thus population vital rates change seasonally. However, knowledge is lacking on patterns of seasonal correlation between growth and survival in sympatric ectotherms, and this knowledge gap limits our understanding of environmental change impacts on animal populations and communities. Here, we investigated sub‐seasonal (two‐month intervals) correlation between growth and survival in three stream fishes (bluehead chub Nocomis leptocephalus, creek chub Semotilus atromaculatus and mottled sculpin Cottus bairdii) in South Carolina, USA, via a mark–recapture survey over 28 months. We found that patterns of temporal correlation between the population vital rates differed among the sympatric species. Growth increased and survival decreased with water temperature in two eurythermal species, resulting in negative correlation between growth and survival. Growth peaked in sub‐seasons with an intermediate water temperature range in a third stenothermal species, while survival decreased with water temperature for this species too. Consequently, there was not significant negative or positive correlation between sub‐seasonal growth and survival in the stenothermal species. Body condition (weight at given length) decreased from May through November in all three species, providing a potential physiological explanation for why survival rates were lower during this period. Negative correlation among population vital rates stabilizes population size over time and buffers animal populations from environmental change because the vital rates are not affected simultaneously in the same direction, indicating some degree of resiliency in the face of climate changes in the two eurythermal species. However, such a demographic mechanism of resiliency could be maintained so long as climate warming does not exceed optimal growth temperature, above which negative correlation between growth and survival may no longer be maintained.
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This Intergovernmental Panel on Climate Change Special Report (IPCC-SREX) explores the challenge of understanding and managing the risks of climate extremes to advance climate change adaptation. Extreme weather and climate events, interacting with exposed and vulnerable human and natural systems, can lead to disasters. Changes in the frequency and severity of the physical events affect disaster risk, but so do the spatially diverse and temporally dynamic patterns of exposure and vulnerability. Some types of extreme weather and climate events have increased in frequency or magnitude, but populations and assets at risk have also increased, with consequences for disaster risk. Opportunities for managing risks of weather- and climate-related disasters exist or can be developed at any scale, local to international. Prepared following strict IPCC procedures, SREX is an invaluable assessment for anyone interested in climate extremes, environmental disasters and adaptation to climate change, including policymakers, the private sector and academic researchers.
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Coral reefs are the 'rain forests' of the ocean, containing the highest diversity of marine organisms and facing the greatest threats from humans. As shallow-water coastal habitats, they support a wide range of economically and culturally important activities, from fishing to tourism. Their accessibility makes reefs vulnerable to local threats that include over-fishing, pollution and physical damage. Reefs also face global problems, such as climate change, which may be responsible for recent widespread coral mortality and increased frequency of hurricane damage. This book, first published in 2006, summarises the state of knowledge about the status of reefs, the problems they face, and potential solutions. The topics considered range from concerns about extinction of coral reef species to economic and social issues affecting the well-being of people who depend on reefs. The result is a multi-disciplinary perspective on problems and solutions to the coral reef crisis.
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Coral reefs are the 'rain forests' of the ocean, containing the highest diversity of marine organisms and facing the greatest threats from humans. As shallow-water coastal habitats, they support a wide range of economically and culturally important activities, from fishing to tourism. Their accessibility makes reefs vulnerable to local threats that include over-fishing, pollution and physical damage. Reefs also face global problems, such as climate change, which may be responsible for recent widespread coral mortality and increased frequency of hurricane damage. This book, first published in 2006, summarises the state of knowledge about the status of reefs, the problems they face, and potential solutions. The topics considered range from concerns about extinction of coral reef species to economic and social issues affecting the well-being of people who depend on reefs. The result is a multi-disciplinary perspective on problems and solutions to the coral reef crisis.
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Coral reefs are the 'rain forests' of the ocean, containing the highest diversity of marine organisms and facing the greatest threats from humans. As shallow-water coastal habitats, they support a wide range of economically and culturally important activities, from fishing to tourism. Their accessibility makes reefs vulnerable to local threats that include over-fishing, pollution and physical damage. Reefs also face global problems, such as climate change, which may be responsible for recent widespread coral mortality and increased frequency of hurricane damage. This book, first published in 2006, summarises the state of knowledge about the status of reefs, the problems they face, and potential solutions. The topics considered range from concerns about extinction of coral reef species to economic and social issues affecting the well-being of people who depend on reefs. The result is a multi-disciplinary perspective on problems and solutions to the coral reef crisis.
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Coral reefs are the 'rain forests' of the ocean, containing the highest diversity of marine organisms and facing the greatest threats from humans. As shallow-water coastal habitats, they support a wide range of economically and culturally important activities, from fishing to tourism. Their accessibility makes reefs vulnerable to local threats that include over-fishing, pollution and physical damage. Reefs also face global problems, such as climate change, which may be responsible for recent widespread coral mortality and increased frequency of hurricane damage. This book, first published in 2006, summarises the state of knowledge about the status of reefs, the problems they face, and potential solutions. The topics considered range from concerns about extinction of coral reef species to economic and social issues affecting the well-being of people who depend on reefs. The result is a multi-disciplinary perspective on problems and solutions to the coral reef crisis.
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Coral reefs are the 'rain forests' of the ocean, containing the highest diversity of marine organisms and facing the greatest threats from humans. As shallow-water coastal habitats, they support a wide range of economically and culturally important activities, from fishing to tourism. Their accessibility makes reefs vulnerable to local threats that include over-fishing, pollution and physical damage. Reefs also face global problems, such as climate change, which may be responsible for recent widespread coral mortality and increased frequency of hurricane damage. This book, first published in 2006, summarises the state of knowledge about the status of reefs, the problems they face, and potential solutions. The topics considered range from concerns about extinction of coral reef species to economic and social issues affecting the well-being of people who depend on reefs. The result is a multi-disciplinary perspective on problems and solutions to the coral reef crisis.
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Coral reefs are the 'rain forests' of the ocean, containing the highest diversity of marine organisms and facing the greatest threats from humans. As shallow-water coastal habitats, they support a wide range of economically and culturally important activities, from fishing to tourism. Their accessibility makes reefs vulnerable to local threats that include over-fishing, pollution and physical damage. Reefs also face global problems, such as climate change, which may be responsible for recent widespread coral mortality and increased frequency of hurricane damage. This book, first published in 2006, summarises the state of knowledge about the status of reefs, the problems they face, and potential solutions. The topics considered range from concerns about extinction of coral reef species to economic and social issues affecting the well-being of people who depend on reefs. The result is a multi-disciplinary perspective on problems and solutions to the coral reef crisis.
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Coral reefs are the 'rain forests' of the ocean, containing the highest diversity of marine organisms and facing the greatest threats from humans. As shallow-water coastal habitats, they support a wide range of economically and culturally important activities, from fishing to tourism. Their accessibility makes reefs vulnerable to local threats that include over-fishing, pollution and physical damage. Reefs also face global problems, such as climate change, which may be responsible for recent widespread coral mortality and increased frequency of hurricane damage. This book, first published in 2006, summarises the state of knowledge about the status of reefs, the problems they face, and potential solutions. The topics considered range from concerns about extinction of coral reef species to economic and social issues affecting the well-being of people who depend on reefs. The result is a multi-disciplinary perspective on problems and solutions to the coral reef crisis.
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Coral reefs are the 'rain forests' of the ocean, containing the highest diversity of marine organisms and facing the greatest threats from humans. As shallow-water coastal habitats, they support a wide range of economically and culturally important activities, from fishing to tourism. Their accessibility makes reefs vulnerable to local threats that include over-fishing, pollution and physical damage. Reefs also face global problems, such as climate change, which may be responsible for recent widespread coral mortality and increased frequency of hurricane damage. This book, first published in 2006, summarises the state of knowledge about the status of reefs, the problems they face, and potential solutions. The topics considered range from concerns about extinction of coral reef species to economic and social issues affecting the well-being of people who depend on reefs. The result is a multi-disciplinary perspective on problems and solutions to the coral reef crisis.
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Coral reefs are the 'rain forests' of the ocean, containing the highest diversity of marine organisms and facing the greatest threats from humans. As shallow-water coastal habitats, they support a wide range of economically and culturally important activities, from fishing to tourism. Their accessibility makes reefs vulnerable to local threats that include over-fishing, pollution and physical damage. Reefs also face global problems, such as climate change, which may be responsible for recent widespread coral mortality and increased frequency of hurricane damage. This book, first published in 2006, summarises the state of knowledge about the status of reefs, the problems they face, and potential solutions. The topics considered range from concerns about extinction of coral reef species to economic and social issues affecting the well-being of people who depend on reefs. The result is a multi-disciplinary perspective on problems and solutions to the coral reef crisis.
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Coral reefs are the 'rain forests' of the ocean, containing the highest diversity of marine organisms and facing the greatest threats from humans. As shallow-water coastal habitats, they support a wide range of economically and culturally important activities, from fishing to tourism. Their accessibility makes reefs vulnerable to local threats that include over-fishing, pollution and physical damage. Reefs also face global problems, such as climate change, which may be responsible for recent widespread coral mortality and increased frequency of hurricane damage. This book, first published in 2006, summarises the state of knowledge about the status of reefs, the problems they face, and potential solutions. The topics considered range from concerns about extinction of coral reef species to economic and social issues affecting the well-being of people who depend on reefs. The result is a multi-disciplinary perspective on problems and solutions to the coral reef crisis.
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The local diversity and global richness of coral reef fishes, along with the diversity manifested in their morphology, behaviour and ecology, provides fascinating and diverse opportunities for study. Reflecting the very latest research in a broad and ever-growing field, this comprehensive guide is a must-read for anyone interested in the ecology of fishes on coral reefs. Featuring contributions from leaders in the field, the 36 chapters cover the full spectrum of current research. They are presented in five parts, considering coral reef fishes in the context of ecology; patterns and processes; human intervention and impacts; conservation; and past and current debates. Beautifully illustrated in full-colour, this book is designed to summarise and help build upon current knowledge and to facilitate further research. It is an ideal resource for those new to the field as well as for experienced researchers.
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The local diversity and global richness of coral reef fishes, along with the diversity manifested in their morphology, behaviour and ecology, provides fascinating and diverse opportunities for study. Reflecting the very latest research in a broad and ever-growing field, this comprehensive guide is a must-read for anyone interested in the ecology of fishes on coral reefs. Featuring contributions from leaders in the field, the 36 chapters cover the full spectrum of current research. They are presented in five parts, considering coral reef fishes in the context of ecology; patterns and processes; human intervention and impacts; conservation; and past and current debates. Beautifully illustrated in full-colour, this book is designed to summarise and help build upon current knowledge and to facilitate further research. It is an ideal resource for those new to the field as well as for experienced researchers.
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The local diversity and global richness of coral reef fishes, along with the diversity manifested in their morphology, behaviour and ecology, provides fascinating and diverse opportunities for study. Reflecting the very latest research in a broad and ever-growing field, this comprehensive guide is a must-read for anyone interested in the ecology of fishes on coral reefs. Featuring contributions from leaders in the field, the 36 chapters cover the full spectrum of current research. They are presented in five parts, considering coral reef fishes in the context of ecology; patterns and processes; human intervention and impacts; conservation; and past and current debates. Beautifully illustrated in full-colour, this book is designed to summarise and help build upon current knowledge and to facilitate further research. It is an ideal resource for those new to the field as well as for experienced researchers.
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Fisheries are important sources of nutrients for people, but fisheries science and management do not consider nutrient information. The result is that fisheries are conducted without knowledge of how exploited species portfolios produce nutrients, how these yields have changed over time, and how they may change in the future. Here, we develop approaches for nutrient-informed analysis, and illustrate their use by applying them to catches from northwest Atlantic fisheries from 1950 to 2014. Relative to catch weights, nutrient yields showed more change over time and greater degrees of concentration in fewer taxa. Species that were minor from a weight perspective were identified as key sources of specific nutrients. Atlantic herring (Clupea harengus) emerge as a cornerstone of regional nutrient yields, with recent yields of some nutrients so disproportionately reliant upon herring as to indicate a potential lack of resilience. Insights such as these emphasize the need for nutrient informed approaches to fisheries assessment.
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In this chapter we focus on the future of the coastal economies, in relation to several climate and Shared Socioeconomic Pathways (SSPs) scenarios addressed in the literature. Once understood their major sources of income, especially in rural Asia, highly dependent on agriculture and fisheries, we examine (in this volume on Blue Economy) first the role of fisheries. We discuss the present state and future estimates that some modelling have shown, reflecting on the effects that this may have on those coastal, mostly rural areas mainly depending on them as source of protein and income. Secondly, we look in detail to particularly relevant areas of coastal economies, the deltas, as one of the most likely affected areas of global change. Based on several sources, mainly gridded or downscaled Gross Domestic Product (GDP) and Human Development Index (HDI) measures, we analyze different paths that some of the large deltas in Asia may encounter under different scenarios, often described globally, making use of existing downscaled data. We conclude that those areas tend to be relatively lower endowed than other areas (especially urban) to address futures, especially unsustainable, fragmented and unequal ones.KeywordsShared socioeconomic pathwaysFisheriesDeltaSocio-economicHuman development indexCoastal economiesGross domestic product (GDP)AsiaDynamic interactive vulnerability assessmentImpactAdaptation and vulnerability (IAV)Purchasing power parityVulnerability indexInvestment deficit index
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Amplified by warming temperatures and drought, recent outbreaks of native bark beetles (Curculionidae: Scolytinae) have caused extensive tree mortality throughout Europe and North America. Despite their ubiquitous nature and important effects on ecosystems, forest recovery following such disturbances is poorly understood, particularly across regions with varying abiotic conditions and outbreak effects. To better understand post‐outbreak recovery across a topographically complex region, we synthesized data from 16 field studies spanning subalpine forests in the Southern Rocky Mountains, USA. From 1997 to 2019, these forests were heavily affected by outbreaks of three native bark beetle species (Dendroctonus ponderosae, Dendroctonus rufipennis, and Dryocoetes confusus). We compared pre‐ and post‐outbreak forest conditions and developed region‐wide predictive maps of post‐outbreak (1) live basal areas, (2) juvenile densities, and (3) height growth rates for the most abundant tree species – aspen (Populus tremuloides), Engelmann spruce (Picea engelmannii), lodgepole pine (Pinus contorta), and subalpine fir (Abies lasiocarpa). Beetle‐caused tree mortality reduced the average diameter of live trees by 28.4% (5.6 cm), and species dominance was altered on 27.8% of field plots with shifts away from pine and spruce. However, most plots (82.1%) were likely to recover towards pre‐outbreak tree densities without additional regeneration. Region‐wide maps indicated that fir and aspen, non‐host species for bark beetle species with the most severe effects (i.e., Dendroctonus spp.), will benefit from outbreaks through increased compositional dominance. After accounting for individual size, height growth for all conifer species was more rapid in sites with low winter precipitation, high winter temperatures, and severe outbreaks. Synthesis: In subalpine forests of the US Rocky Mountains, recent bark beetle outbreaks have reduced tree size and altered species composition. While eventual recovery of the pre‐outbreak forest structure is likely in most places, changes in species composition may persist for decades. Still, forest communities following bark beetle outbreaks are widely variable due to differences in pre‐outbreak conditions, outbreak severity, and abiotic gradients. This regional variability has critical implications for ecosystem services and susceptibility to future disturbances.
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Coral populations on the Great Barrier Reef (GBR) are experiencing long-term shifts in size structure, including steep declines in small colonies, driving major concerns for recovery through the supply of new recruits. Whilst coral restoration began on the GBR in 2018, the combined influence of natural recruitment and outplanting for coral population recovery has not been evaluated. Here, we assessed 2 sites (Rayban and Mojo) at Opal Reef that were subject to intensive outplant efforts over a 3 yr period (2018-2021). Coral cover did not change significantly, with a baseline of 15% in 2018 and a cover of 28 and 25% in Rayban outplant and control areas, respectively, in 2021, while Mojo exhibited a coral cover of 38% in 2018 and 52% (outplant area) and 29% (control area) in 2021. Natural recruitment in 2021 did not vary by site and was characterised by a settlement rate of 5.5 and 3.7 recruits tile ⁻¹ at Rayban and Mojo, respectively. Juvenile coral abundance and diversity were similar for control and outplant areas at each site. Over the 3 yr period, coral cover as a metric did not identify differences between control and outplant areas; however, size-frequency distributions of key coral taxa revealed a higher frequency of small to mid-sized colonies in outplant communities compared to controls. Given that no differences were observed in recruitment rates or juvenile abundances, variations in population structure appear to be driven by planting efforts rather than natural recovery. Our results demonstrate the need for combined monitoring of natural versus intervention-based rehabilitation to understand the impact of coral propagation efforts for local site recovery.
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In the context of global environmental change ecosystem resilience becomes critical for long term survival of species and consistent delivery of ecosystem services. Concerns however exist on whether managing ecosystems for resilience would actually support biodiversity conservation. Current focus of empirical studies on species richness as the main measure of biodiversity may result in underestimation of the link between biodiversity and ecosystem resilience. A closer look at different levels of biodiversity, namely interspecific, intraspecific and ecosystem diversity allow better understanding of how biodiversity underpins resilience. Thus, a holistic approach to biodiversity research and management is needed to maintain ecosystem resilience in the context of global environmental change. All three level of biodiversity need to be considered. Landscape Approach is likely to be the most effective strategy in conservation, because preserving biodiversity at a landscape level is likely to simultaneously ensure metapopulation genetic diversity, secure high functional redundancy and response diversity, and preserve ecological memory, which ultimately ensure ecosystem resilience and consistent flow of ecosystem services.
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Social-ecological systems underpinning nature-based solutions (NbS) must be resilient to changing conditions if they are to contribute to long-term climate change adaptation. We develop a two-part conceptual framework linking social-ecological resilience to adaptation outcomes in NbS. Part one determines the potential of NbS to support resilience based on assessing whether NbS affect key mechanisms known to enable resilience. Examples include social-ecological diversity, connectivity, and inclusive decision-making. Part two includes adaptation outcomes that building social-ecological resilience can sustain, known as nature's contributions to adaptation (NCAs). We apply the framework to a global dataset of NbS in forests. We find evidence that NbS may be supporting resilience by influencing many enabling mechanisms. NbS also deliver many NCAs such as flood and drought mitigation. However, there is less evidence for some mechanisms and NCAs critical for resilience to long-term uncertainty. We present future research questions to ensure NbS can continue to support people and nature in a changing world. Expected final online publication date for the Annual Review of Environment and Resources, Volume 47 is October 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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With the continued strengthening of global climate change, various extreme climate events have become increasingly prominent. Typhoons are the most disastrous weather event that cause severe losses to the economy, agriculture, transportation, communication, and ecosystem in coastal regions. The super typhoon Sarika that hit Hainan Island on October 18, 2016, lasted for 15 h, and it was the most severe typhoon that hit this island in October since 1970. The coastal land of Hainan Island experienced gales with an average speed of 35 m/s. In this study, we evaluated the impact of the super typhoon Sarika on vegetation by performing normalized difference vegetative index (NDVI) difference analysis using MODIS multi-temporal images acquired before and after the typhoon. The assessment of typhoons depends on the land-use types and landscape topography of slope, aspect, and altitude. The results indicated that the super typhoon Sarika seriously hit forestry, agriculture, shrubs, plantations, and orchards on Hainan Island. Overall, 79% of vegetation exhibited a negative change, whereas only 21% of vegetation exhibited a positive change in NDVI after the super typhoon Sarika. Agriculture was most severely impacted by the typhoon, where more than 81% of areas exhibited a decrease in NDVI, followed by plantations and orchards, where 77% of areas exhibited a decrease in NDVI. Additionally, the impact of the typhoon on vegetation was affected by the degree of NDVI decrease with the altitude, slope, and aspect. In conclusion, vegetation damage is associated with land cover types, altitude, aspect, and slope. NDVI decreased more in low-altitude plain and coastal areas than in higher altitude montane forest areas.
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This chapter aims to analyze the implications that urban sustainability, socio-ecosystems, and ecosystem services have as the bases to design the urban green growth strategies. The method used is the analytic based on the theoretical and conceptual literature reviews on the topics described. Urban sustainability and environmental performance integrates biodiversity and socio-ecosystems for the provision of better quality ecosystem services supported by green infrastructure design into the green projects aimed to achieve economic and environmental benefits. It is concluded that the ecosystem services and human well-being may suffer irreversible severe declines if sustainability is not built based on biodiversity of socio ecosystems, green infrastructure, and natural capital.
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Arboreal frugivores, such as primates and hornbills, are important seed dis- persers for many tropical plant species, yet the degree to which they use the same resources is unknown. If primates and hornbills consume the same fruit species, they may be redundant in their roles as seed dispersers, and the loss of one of these taxa may be compensated for by the other. To examine resource use by tropical frugivores, we quantified the feeding habits of two hornbill species, Ceratogymna atrata and C. cylindricus, and five primate species, Colobus guereza, Lophocebus albigena, Cercopithecus pogonias, C. cephus, and C. nictitans, in the lowland rainforest of south-central Cameroon. Based on over 2200 feeding observations recorded between January and December 1998, we characterized the diets and estimated dietary overlap among frugivore species. Previous studies have cal- culated dietary overlap by counting the number of diet species that two animals share, often leading to inflated estimates of overlap. Our method incorporated the proportional use of diet species and fruit availability into randomization procedures, allowing a clearer as- sessment of the actual degree of overlap. This added complexity of analysis revealed that, although the diets of a hornbill and a primate species may have as many as 36 plant species in common, actual dietary overlap is low. These results suggested that there are distinct hornbill and primate feeding assemblages, with primates consuming a greater diversity of plant species and higher levels of nonfruit items like leaves and seeds. Using Correspon- dence Analysis, we also identified two primate assemblages, separated largely by degree of frugivory and folivory. In addition, we found that hornbills feed at significantly higher strata in the forest canopy and eat fruits of different colors than primates. Averaged across the year, overlap between groups (hornbill-primate) was significantly lower than combined within-group overlap (primate-primate and hornbill-hornbill), showing that primates and hornbills have dissimilar diets and are not redundant as seed dispersers. In equatorial Africa, primate populations face greater declines than hornbill populations because of hunting. It is unlikely that seed dispersal by hornbills will compensate for the loss of primates in maintaining forest structure.
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A simulation model, recent experiments, and the literature provide consistent evidence that megafauna extinctions caused by human hunting could have played as great a role as climate in shifting from a vegetation mosaic with abundant grass-dominated steppe to a mosaic dominated by moss tundra in Beringia at the end of the Pleistocene. General circulation models suggest that the Pleistocene environment of Beringia was colder than at the present with broadly similar wind patterns and precipitation but wetter soils. These and other observations suggest that the steppelike vegetation and dry soils of Beringia in the late Pleistocene were not a direct consequence of an arid macroclimate. Trampling and grazing by mammalian grazers in tundra cause a shift in dominance from mosses to grasses. Grasses reduce soil moisture more effectively than mosses through high rates of evapotranspiration. Results of a simulation model based on plant competition for water and light and plant sensitivity to grazers and nutrient supply predict that either of two vegetation types, grass-dominated steppe or moss-dominated tundra, could exist in Beringia under both current and Pleistocene climates. The model suggests that moss-dominated tundra is favored when grazing is reduced below levels that are in equilibrium with climate and vegetation. Together these results indicate that mammalian grazers have a sufficiently large effect on vegetation and soil moisture that their extinction could have contributed substantially to the shift from predominance of steppe to tundra at the Pleistocene-Holocene boundary. Our hypothesis suggests a mechanism by which the steppe ecosystem could be restored to portions of its former range. We also suggest that mammalian impacts on vegetation are sufficiently large that future vegetation cannot be predicted from climate scenarios without considering the role of mammals.
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In order to assess how diversity changes over time at sites undergoing environmental change, we examined three data sets on long-term trends in taxonomic richness and composition: (1) 22 years of rodent censuses from a site in the Chihuahuan Desert of Arizona; (2) 50 years of bird surveys from a three-county region of northern Michigan; and (3) approximately 10,000 years of pollen records from two sites in Europe. In all three cases, richness has remained remarkably constant despite large changes in composition. The results suggest that while species composition may be highly variable and change substantially in response to environmental change, species diversity is an emergent property of ecosystems that is often maintained within narrow limits. Such regulation of diversity requires maintenance of relatively constant levels of productivity and resource availability and an open system with opportunity for compensatory colonizations and extinctions. In addition to studying the effects of diversity on biogeochemical processes, it will often be useful to think of species richness as an emergent consequence of ecosystem processes.
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The ecological consequences of biodiversity loss have aroused considerable interest and controversy during the past decade. Major advances have been made in describing the relationship between species diversity and ecosystem processes, in identifying functionally important species, and in revealing underlying mechanisms. There is, however, uncertainty as to how results obtained in recent experiments scale up to landscape and regional levels and generalize across ecosystem types and processes. Larger numbers of species are probably needed to reduce temporal variability in ecosystem processes in changing environments. A major future challenge is to determine how biodiversity dynamics, ecosystem processes, and abiotic factors interact.
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This paper considers the significance of biological diversity in relation to large-scale processes in complex and dynamic ecological-economic systems. It focuses on functional diversity, and its relation to production and maintenance of ecological services that underpin human societies. Within functional groups of organisms two important categories of species are identified: keystone process species and those essential for ecosystem resilience. The latter group represents ''natural insurance capital.'' In addition to basic research on the interplay among biological diversity, functional performance, and resilience in complex self-organizing systems, we suggest that a functional approach has two main implications for a strategy for biodiversity conservation: (1) Biodiversity conservation to assure the resilience of ecosystems is required for all systems, no matter how heavily impacted they are. It should not be limited to protected areas. (2) The social, cultural, and economic driving forces in society that cause biodiversity loss need to be addressed directly. Specifically, (a) differences between the value of biological diversity to the private individual and its fundamental value to society as a whole need to be removed; (b) social and economic policies that encourage biodiversity loss should be reformed, especially where there is a risk of irreversible damage to ecosystems and diversity; and (c) institutions that are adaptive and work in synergy with ecosystem processes and functions are critical and should be created at all levels.
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Addresses the problem of which biota to choose to best satisfy the conservation goals for a particular region in the face of inadequate resources. Biodiversity is taken to be the integration of biological variability across all scales, from the genetic, through species and ecosystems, to landscapes. The best way to minimize species loss is to maintain the integrity of ecosystem function. The important questions therefore concern the kinds of biodiversity that are significant to ecosystem functioning. To best focus our efforts we need to establish how much (or how little) redundancy there is in the biological composition of ecosystems. An approach is suggested, based on the use of functional groups of organisms defined according to ecosystem processes. Functional groups with little or no redundancy warrant priority conservation effort. -from Author
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In order to investigate the impact of freshwater acidification on the trophic structure of macroinvertebrate communities, we performed a study on 22 forested headwater streams characterised by different degrees of acidification (mean pH = 4.49 to 6.98). Results showed that in acidic streams all functional feeding groups were affected in terms of taxonomic richness. As far as the population density was concerned, only a few acid‐tolerant taxa of shredders and predators showed an increasing abundance under acidic conditions. Trophic structure of acidified streams appeared to be deeply impacted with a large contribution of shredders and a complete disappearance of scrapers. In contrast, in circumneutral streams, we found that each functional feeding group had an almost equal share of the trophic web.
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Aquatic ecologists have many models for size distributions of pelagic communities. However, few studies have looked for discontinuities (clumps of similarly sized species or gaps of sizes that contain no or relatively few species) in pelagic community size structure. We investigated size distribution characteristics in aquatic communities by calculating kernel density functions for plankton and fish in 11 lakes in Wisconsin. Size distributions in aquatic communities of these lakes were not smooth. Rather, multiple lump and gap regions were found within each functional group of phytoplankton, zooplankton, and fish. Simulations showed the gaps could not be explained by incomplete censuses of species or by systematic underestimation of intraspecific size variation. In an experimentally enriched lake, before and after comparisons showed lumps were not affected by large additions of P and N, even though biomass and production changed substantially. Lump regions in the two lakes with both food web manipulations and nutrient enrichment were substantially less similar pre- versus postenrichment than the reference lake and the lake with only nutrients added, but lump number remained relatively unchanged. Lakes that differed widely in nutrient status, trophic structure, species diversity, and area had similar size distributions. Comparisons of functional groups showed that phytoplankton had more lumps than zooplankton. In these north temperate lakes, size distribution characteristics seem to be conservative properties shaped by common regional ecosystem processes and organism patterns and not by lake-specific factors.
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Flying foxes of the genus Pteropus (Pteropodidae: Chiroptera) play important roles as pollinators and seed dispersers in oceanic-island forest communities. This research examined general theories of diet breadth, diet selection, and the evolution of feeding strategies in bats in light of information from members of the genus Pteropus that inhabit oceanic islands. The feeding ecology of two species of flying fox, Pteropus samoensis and Pteropus tonganus on the Samoan archipelago, was examined in detail by direct observation and by examining feeding refuse. P. samoensis and P. tonganus fed on over 78 plant species from 39 families throughout their range and on over 69 plant species in Samoa alone. Flying foxes interacted with 59% of the forest tree species in Amalau Valley for fruit or flower resources. Twenty-eight percent of the forest trees were commonly used, and 79% of forest canopy trees were used. Broad overlap in resource use was noted between P. samoensis and P. tonganus with over 22 shared plant species. Seasonal variation in fruit resource use was quantified with a preference index. Flying foxes ate a taxonomically nonrandom subset of fruit species and generally preferred primary forest fruits to those in the secondary forest. Six plant families (Sapotaceae, Mrytaceae, Moraceae, Combretaceae, Fabaceae, and Sapindaceae) were particularly important to flying foxes in Samoa. However, a set of core plant taxa does not exist for Pteropus spp. in Samoa. Differences in the evolution of feeding strategies between mainland fruit-eating chiroptera and island species likely reflect differences in the spatio-temporal availability of resources in the two systems.
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Biodiversity plays a vital role for ecosystem functioning in a changing environment. Yet theoretical approaches that incorporate diversity into classical ecosystem theory do not provide a general dynamic theory based on mechanistic principles. In this paper, we suggest that approaches developed for quantitative genetics can be extended to ecosystem functioning by modeling the means and variances of phenotypes within a group of species. We present a framework that suggests that phenotypic variance within functional groups is linearly related to their ability to respond to environmental changes. As a result, the long-term productivity for a group of species with high phenotypic variance may be higher than for the best single species, even though high phenotypic variance decreases productivity in the short term, because suboptimal species are present. In addition, we find that in the case of accelerating environmental change, species succession in a changing environment may become discontinuous. Our work suggests that this phenomenon is related to diversity as well as to the environmental disturbance regime, both of which are affected by anthropogenic activities. By introducing new techniques for modeling the aggregate behavior of groups of species, the present approach may provide a new avenue for ecosystem analysis.
Article
1. Species extinction in fragmented habitats is a non-random process described by transient, rather than equilibrium dynamics. Therefore, 'static' approaches focusing on experimentally established spatial gradients of diversity may fail to capture essential aspects of ecosystem responses to species loss. 2. Here we document temporal changes in microarthropod species abundance, biomass and richness during a community disassembly trajectory following experimental habitat fragmentation of a moss-based microecosystem. 3. Habitat fragmentation reduced heterotrophic species richness and community biomass in remnant moss fragments. Extinction was biased towards rare species, and thus occurred initially without significant changes in total community abundance and biomass. Eventual reductions in abundance and biomass were found to lag behind observed declines in species richness. 4. The presence of moss-habitat corridors connecting fragments to a large 'mainland' area coupled with an immigration rescue effect maintained microarthropod richness, abundance and biomass within remnant fragments. 5. Our results indicate that both the order of species loss and the dynamics of remnant populations influence the magnitude and timing of ecosystem-level responses to habitat destruction and isolation.
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The South Pacific islands of Samoa have two extant flying fox species, Pteropus samoensis and P. tonganus. Following two severe cyclonic storms, we examined their differential behavioral responses and evaluated the effectiveness of recently established reserves in providing refugia. Although the cyclones disrupted activity patterns and foraging behavior for both species, comparisons with pre-storm data suggested that the more common, widely distributed P. tonganus experienced more severe population declines than the endemic P. samoenis. This differential mortality could be explained by a combination of ecological and behavioral factors. P. tonganus had a greater tendency to enter villages to feed on fallen cultivated fruits, making it more vulnerable to human hunting and predation by domestic animals. In addition, P. samoensis appeared to use survival strategies not observed in P. tonganus. Leaves, which were far more available than flowers or fruits in the immediate post-storm period, comprised a major part of the post-storm diet of P. samoensis. This species also fed on the fleshy bracts of a storm-resistant native liana, (Freycinetia reineckei). In contrast, a seasonally important food of P. tonganus is nectar from the delicate flowers of Syzygium inophylloides (asi), a canopy tree that is very vulnerable to wind damage and has become increasing scarce with the clearing of lowland forest. Rainforest reserves, established prior to the storms, served as adequate refugia for local P. samoensis populations, which appeared to feed relatively close to their roosts, primarily in native forest, but did not protect P. tonganus populations, which traveled outside reserves to forage in areas lacking hunting bans. Although wind damage was patchy and not consistent between storms, areas of high topographic complexity (e.g., volcanic cones and deep valleys) were the most likely to retain areas with some foliage and should be given priority in the design of future reserves.
Article
We evaluated the hypothesis that poachers reduce the abundance of herbivorous mammals, and that this, in turn, alters seed dispersal, seed predation, and seedling recruitment for two palms (Attalea butyraceae and Astrocaryum standleyanum) in central Panama. Using physical evidence left by poachers and interviews with forest guards, we quantified poaching intensity for eight forest sites. We quantified mammal abundance using transect counts and small-mammal traps. Abundance was inversely related to poaching intensity for 9 of 11 mammal species (significantly so for 5 species), confirming the first component of the hypothesis. The outcome of interactions among seeds, mammals, and beetles also varied with poaching intensity. Nonvolant mammals were the only seed-dispersal agents, and rodents and beetles were the only seed predators. We quantified seed fate by examining the stony endocarps that encase the seeds of both palms. The large, durable endocarps were located easily on the forest floor and bear characteristic scars when a rodent or beetle eats the enclosed seed. The proportion of seeds dispersed away from beneath fruiting conspecifics was inversely related to poaching intensity, ranging from 85% to 99% at protected sites where mammals were abundant and from 3% to 40% at unprotected sites where poachers were most active. The proportion of dispersed seeds destroyed by beetles was directly related to poaching intensity, ranging from 0% to 10% at protected sites and from 30% to 50% at unprotected sites. The proportion of dispersed seeds destroyed by rodents was inversely related to poaching intensity, ranging from 85% to 99% at protected sites and from 4% to 50% at unprotected sites. Finally, seedling densities were directly related to poaching intensity. There was no single relationship between poaching intensity and the biotic interactions that determine seedling recruitment. The net effect of poaching on seedling recruitment can be determined only empirically. For these palms, seedling densities were directly related to poaching intensity.Resumen: Evaluamos la hipótesis que los cazadores reducen la abundancia de mamíferos herbívoros y que esto, a su vez, altera la dispersión de semillas, la depredación de semillas y el reclutamiento de plántulas de dos palmeras (Attalea butyraceae y Astrocaryum standleyanum) en Panamá central. La intensidad de cacería fue cuantificada para ocho sitios dentro de bosque, utilizando la evidencia física dejada por los cazadores y entrevistas con los guardaparques. La abundancia de mamíferos fue cuantificada usando conteos a lo largo de transectos y trampas para los mamíferos pequeños. La abundancia estuvo inversamente relacionada a la intensidad de cacería para nueve de 11 especies de mamíferos (significativamente en cinco especies), confirmando el primer componente de la hipótesis. El resultado de las interacciones entre semillas, mamíferos y escarabajos, también varió con la intensidad de cacería. La suerte de las semillas fue cuantificada utilizando el endocarpo duro que recubre a las semillas de ambas palmeras. Estos endocarpos grandes y durables son fácilmente encontrados sobre el suelo del bosque, y tienen cicatrices características cuando un roedor o escarabajo comió la semilla dentro de éste. Los mamíferos no voladores son los únicos agentes que dispersan estas semillas, y los roedores y escarabajos son los únicos depredadores de las mismas. La proporción de las semillas dispersadas, lejos de abajo de los coespecíficos en fructificación, estuvo inversamente relacionada a la intensidad de cacería (dentro de un rango desde 85% hasta 99% en los sitios protegidos donde los mamíferos eran abundantes, y desde 3% hasta 40% en los sitios desprotegidos donde los cazadores estaban más activos). La proporción de semillas dispersadas exterminadas por escarabajos estuvo directamente relacionada a la intensidad de cacería (dentro de un rango desde 0% hasta 10% en los sitios protegidos, y desde 30% hasta 50% en los sitios desprotegidos). La proporción de semillas dispersadas exterminadas por roedores estuvo inversamente relacionada a la intensidad de cacería (dentro de un rango desde 85% hasta 99% en los sitios protegidos, y desde 4% hasta 50% en los sitios desprotegidos). Finalmente, las densidades de plántulas estuvieron directamente relacionadas a la intensidad de cacería. No se encontró una relación única entre la intensidad de cacería y las interacciones bióticas que determinan el reclutamiento de plántulas. El efecto neto de la cacería sobre el reclutamiento de plántulas solamente puede ser determinado empíricamente.
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Large differences in community structure of sea urchins and finfish have been observed in Kenyan reef lagoons. Differences have been attributed to removal of finfish predators through human fishing activities. This study attempted to determine (i) the major sea urchin finfish predators, (ii) the effect of predation on sea-urchin community structure, and (iii) the possible effect of sea urchin increases and finfish decreases on the lagoonal substrate. Six reefs, two protected and four unprotected, were compared for differences in finfish abundance, sea urchin abundance and diversity and substrate cover, diversity and complexity. Comparisons between protected and unprotected reefs indicated that finfish populations were ca. 4 x denser in protected than unprotected reefs. Sea urchin populations were >100 x denser and predation rates on a sea urchin, Echinometra mathaei, were 4 x lower in unprotected than in protected reefs. The balistidae (triggerfish) was the single sea-urchin finfish predator family which had a higher population density in protected than in unprotected reefs. Balistid density was positively correlated with predation rates on tethered E. mathaei (r=0.88; p
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Current natural resource management seldom takes the ecosystem functions performed by organisms that move between systems into consideration. Organisms that actively move in the landscape and connect habitats in space and time are here termed “mobile links.” They are essential components in the dynamics of ecosystem development and ecosystem resilience (that is, buffer capacity and opportunity for reorganization) that provide ecological memory (that is, sources for reorganization after disturbance). We investigated the effects of such mobile links on ecosystem functions in aquatic as well as terrestrial environments. We identify three main functional categories: resource, genetic, and process linkers and suggest that the diversity within functional groups of mobile links is a central component of ecosystem resilience. As the planet becomes increasingly dominated by humans, the magnitude, frequency, timing, spatial extent, rate, and quality of such organism-mediated linkages are being altered. We argue that global environmental change can lead to (a) the decline of essential links in functional groups providing pollination, seed dispersal, and pest control; (b) the linking of previously disconnected areas, for example, the spread of vector-borne diseases and invasive species; and (c) the potential for existing links to become carriers of toxic substances, such as persistent organic compounds. We conclude that knowledge of interspatial exchange via mobile links needs to be incorporated into management and policy-making decisions in order to maintain ecosystem resilience and hence secure the capacity of ecosystems to supply the goods and services essential to society.
Article
This study tested an hypothesis concerning patterns in species abundance in ecological communities. Why do the majority of species occur in low abundance, with just a few making up the bulk of the biomass? We propose that many of the minor species are analogues of the dominants in terms of the ecosystem functions they perform, but differ in terms of their capabilities to respond to environmental stresses and disturbance. They thereby confer resilience on the community with respect to ecosystem function. Under changing conditions, ecosystem function is maintained when dominants decline or are lost because functionally equivalent minor species are able to substitute for them. We have tested this hypothesis with respect to ecosystem functions relating to global change. In particular, we identified five plant functional attributes—height, biomass, specific leaf area, longevity, and leaf litter quality—that determine carbon and water fluxes. We assigned values for these functional attributes to each of the graminoid species in a lightly grazed site and in a heavily grazed site in an Australian rangeland. Our resilience proposition was cast in the form of three specific hypotheses in relation to expected similarities and dissimilarities between dominant and minor species, within and between sites. Functional similarity—or ecological distance—was determined as the euclidean distance between species in functional attribute space. The analyses provide evidence in support of the resilience hypothesis. Specifically, within the lightly grazed community, dominant species were functionally more dissimilar to one another, and functionally similar species more widely separated in abundance rank, than would be expected on the basis of average ecological distances in the community. Between communities, depending on the test used, two of three, or three of four minor species in the lightly grazed community that were predicted to increase in the heavily grazed community did in fact do so. Although there has been emphasis on the importance of functional diversity in supporting the flow of ecosystem goods and services, the evidence from this study indicates that functional similarity (between dominant and minor species, and among minor species) may be equally important in ensuring persistence (resilience) of ecosystem function under changing environmental conditions.
Article
There have been several earlier studies that addressed the influence of natural disturbance regimes on coral reefs. Humans alter natural disturbance regimes, introduce new stressors, and modify background conditions of reefs. We focus on how coral reef ecosystems relate to disturbance in an increasingly human-dominated environment. The concept of ecosystem resilience—that is, the capacity of complex systems with multiple stable states to absorb disturbance, reorganize, and adapt to change—is central in this context. Instead of focusing on the recovery of certain species and populations within disturbed sites of individual reefs, we address spatial resilience—that is, the dynamic capacity of a reef matrix to reorganize and maintain ecosystem function following disturbance. The interplay between disturbance and ecosystem resilience is highlighted. We begin the identification of spatial sources of resilience in dynamic seascapes and exemplify and discuss the relation between “ecological memory” (biological legacies, mobile link species, and support areas) and functional diversity for seascape resilience. Managing for resilience in dynamic seascapes not only enhances the likelihood of conserving coral reefs, it also provides insurance to society by sustaining essential ecosystem services.
Article
 The consequences of macroalgal overgrowth on reef fishes and means to reverse this condition have been little explored. An experimental reduction of macroalgae was conducted at a site in the Watamu Marine National Park in Kenya, where a documented increase in macroalgal cover has occurred over the last nine years. In four experimental 10 m by 10 m plots, macroalgae were greatly reduced (fleshy algal cover reduced by 84%) by scrubbing and shearing, while four similar plots acted as controls. The numerical abundance in all fish groups except wrasses and macroalgal-feeding parrotfishes (species in the genera Calotomus and Leptoscarus) increased in experimental algal reduction plots. Algal (Sargassum) and seagrass (Thalassia) assays, susceptible to scraping and excavating parrotfishes, were bitten more frequently in the algal reduction plots one month after the manipulation. Further, surgeonfish (Acanthurus leucosternon and A. nigrofuscus) foraging intensity increased in these algal reduction plots. The abundance of triggerfishes increased significantly in experimental plots relative to control plots, but densities remained low, and an index of sea urchin predation using tethered juvenile and adult Echinometra mathaei showed no differences between treatments following macroalgal reduction. Dominance of reefs by macrofleshy algae appears to reduce the abundance of fishes, mostly herbivores and their rates of herbivory, but also other groups such as predators of invertebrates (triggerfishes, butterflyfishes and angelfishes).
Article
The dominant protocol to study the effects of plant diversity on ecosystem functioning has involved synthetically assembled communities, in which the experimental design determines species composition. By contrast, the composition of naturally assembled communities is determined by environmental filters, species recruitment and dispersal, and other assembly processes. Consequently, natural communities and ecosystems can differ from synthetic systems in their reaction to changes in diversity. Removal experiments, in which the diversity of naturally assembled communities is manipulated by removing various components, complement synthetic-assemblage experiments in exploring the relationship between diversity and ecosystem functioning. Results of recent removal experiments suggest that they are more useful for understanding the ecosystem effects of local, nonrandom extinctions, changes in the natural abundance of species, and complex interspecific interactions. This makes removal experiments a promising avenue for progress in ecological theory and an important source of information for those involved in making land-use and conservation decisions.
Article
Complex dynamic ecosystems are important natural capital assets. We investigate how Swedish national policy has approached these assets in its work on environmental indicators. In particular, we are interested in whether or not the indicators address ecosystem performance. We discuss our inventory of Swedish indicators in the context of ecosystem services, such as source and sink functions, and the capacity of ecosystems to sustain these functions for human well-being. We find that effective indicators have been developed to reflect energy and material flows within society and how human activities put pressure on the environment. The part of natural capital that concerns living systems is reflected in several of the Swedish indicators in a progressive fashion, but indicators that capture the dynamic capacity of ecosystems in sustaining the flow of source and sink functions need to be further developed. We provide examples of recent developments that have started to address such indicators in the context of ecosystem resilience and environmental change, and discuss directions for their further development. We stress the importance of monitoring ecosystem resilience and performance to avoid undesirable state shifts and building ecological knowledge and understanding of this capacity into environmental indicators and their associated management institutions.
Article
Facing a human-dominated world, ecologists are now reconsidering the role of disturbance for coral reef ecosystem dynamics. Human activities alter the natural disturbance regimes of coral reefs by transforming pulse events into persistent disturbance or even chronic stress, by introducing new disturbance, or by suppressing or removing disturbance. Adding these alterations to natural disturbance regimes will probably result in unknown synergistic effects. Simultaneously, humans are altering the capacity of reefs to cope with disturbance (e.g. by habitat fragmentation and reduction of functional diversity), which further exacerbates the effects of altered disturbance regimes. A disturbance that previously triggered the renewal and development of reefs might, under such circumstances, become an obstacle to development. The implications of these changes for reef-associated human activities, such as fishing and tourism, can be substantial.
Article
1, An understanding of the links between life histories and responses to exploitation could provide the basis for predicting shifts in community structure by identifying susceptible species and linking life-history tactics with population dynamics. 2, We examined long-term trends in the abundance of species in the North Sea bottom-dwelling (demersal) fish community. Between 1925 and 1996 changes in species composition led to an increase in mean growth rate, while mean maximum size, age at maturity and size at maturity decreased. The demersal fish community was increasingly heavily fished during this period. 3, Trends in mean life-history characteristics of the community were linked to trends in abundance of component species. An approach based on phylogenetic comparisons was used to examine the differential effects of fishing on individual species with contrasting life histories. 4, Those species that decreased in abundance relative to their nearest relative, matured later at a greater size, grew more slowly towards a greater maximum size and had lower rates of potential population increase. The phylogenetically based analyses demonstrated that trends in community structure could be predicted from the differential responses of related species to fishing, 5, This is the first study to link exploitation responses of an entire community to the life histories of individual species, The results demonstrate that fishing has greater effects on slower growing, larger species with later maturity and lower rates of potential population increase. The comparative approach provides a basis for predicting structural change in other exploited communities.
Article
Myrica faya, an introduced actinorhizal nitrogen fixer, in invading young volcanic sites in Hawaii Volcanoes National Park. We examined the population biology of the invader and ecosystem-level consequences of its invasion in open-canopied forests resulting from volcanic cinder-fall. Although Myrica faya is nominally dioecious, both males and females produce large amounts of fruit that are utilized by a number of exotic and native birds, particularly the exotic Zosterops japonica. In areas of active colonization, Myrica seed rain under perch trees of the dominant native Metrosideros polymorpha ranged from 6 to 60 seeds m⁻² yr⁻¹; no seeds were captured in the open. Planted seeds of Myrica also germinated an established better under isolated individuals of Metrosideros than in the open. Diameter growth of Myrica is > 15-fold greater than that of Metrosideros, and the Myrica population is increasing rapidly. Rates of nitrogen fixation were measured using the acetylene reduction assay calibrated with ¹⁵N. Myrica nodules reduced acetylene at between 5 and 20 μmol g⁻¹ h⁻¹, a rate that extrapolated to nitrogen fixation of 18 kg ha⁻¹ in a densely colonized site. By comparison, all native sources of nitrogen fixation summed to 0.2 kg ha⁻¹ yr⁻¹, and precipitation added < 4 kg ha⁻¹ yr⁻¹. Measurements of litter decomposition and nitrogen release, soil nitrogen mineralization, and plant growth in bioassays all demonstrated that nitrogen fixed by Myrica becomes available to other organisms as well. We conclude that biological invasion by Myrica faya alters ecosystem-level properties in this young volcanic area; at least in this case, the demography and physiology of one species controls characteristics of a whole ecosystem.
Article
Community ecology and ecosystem ecology seem to have existed in different worlds. Levin (1989) suggests that the gulf between the two is the consequence of the different historical traditions in each. Community ecology, for example, emerged from basic studies, where generalized patterns were sought in the natural interactions among the biota. From the outset, the goal has been to deduce general and simple theory. On the other hand, many of the modelling approaches developed to understand ecosystem dynamics emerged from specific applied problems, where not only biotic but abiotic and human disturbances transformed ecosystem function. That tradition, therefore, is often more complete, but at the price of producing a collection of complex specific examples from which generalization is difficult.