Tidally influenced coastal forested wetlands can be divided into two broad categories, mangroves and freshwater forested wetlands. These forested wetlands perform valuable ecosystem services, and both are endangered by threats of sea level rise and land use. Understanding the mechanisms that control the distribution of tidal forests has been greatl...
... saltmarsh and mangroves), with non-saline coastal wetlands (e.g. coastal floodplain wetlands, freshwater swamps) largely overlooked (Williams et al. 2019). Climate change is expected to lead to sea level rise (SLR), salinisation of groundwaters, shoreline retreat, altered rainfall, warming and increased severity of extreme weather events (floods, fires, cyclones), all of which may significantly alter the composition, structure, and function of coastal freshwater wetlands (CFWs; IPCC 2014; Grieger et al. 2020), exacerbating other pressures. ...
Coastal freshwater wetlands (CFWs) are among the most understudied wetlands globally and are highly vulnerable to projected climate changes. To address CFW knowledge gaps in south-east Queensland, Australia, we surveyed the floristic composition and structure of wooded CFWs and explored variation in vegetation patterns in relation to selected environmental drivers. Understorey and shrub assemblages were surveyed using a cover-class scale and stem counts for tree species abundance. Vegetation structure attributes (stem density, basal area) were calculated from survey data. Redundancy analysis was used to investigate drivers of vegetation structure and the species composition of each stratum. Vegetation structure patterns were associated with gradients of rainfall, soil moisture, salinity and pH. Understorey species composition was associated with wallum wetland species, native perennial grass and herb species, and vegetation patterns of the canopy. Common CFW species, namely Melaleuca quinquenervia and Eucalyptus tereticornis, dominated tree assemblage variation. Overall, CFW vegetation exhibited strong associations with gradients of salinity, rainfall, groundwater dependence and disturbance. Alterations to key drivers of vegetation pattern with future climate changes are likely to markedly influence the composition, structure and function of CFW vegetation communities. Action is therefore required to maintain CFW vegetation communities and ecological function in these diverse and unique wetland systems.
Humans have remained highly dependent on the availability of ecosystem services (ES). Over the past 300 years (more intensely in the past seven decades), human activities have degraded the ecosystems and lowered the availability of ES. This has resulted in foregone benefits of well-functioning of ecosystems and ES. Having recognized the multi-dimensional aspects of values of ES, the current research trajectory is inclined towards institutionalizing the science of valuing nature's contributions that have aimed to spearhead discussions with the transdisciplinary academic community. This paper explores the studies conducted on the overarching theme of 'ES valuation'. Primarily, the study reviews five studies:. The review begins by examining the evolution and growth of the ES research in economic contexts. It presented how different conceptual frameworks were applied in ES research to show connections of ES with human well-being that contextualizes valuation. Wetlands are multi-functional ecosystems that contribute immensely to human well-being. The studies on wetland ecosystems (WES) have been mostly covered in many developed countries and few developing countries. The second part of the study focuses on reviewing three aspects of wetland studies: (1) how do we define wetlands and how different ES of wetlands can be categorized? (2) what were the causes and impacts of wetland loss and degradation? (3) what do the empirical valuation studies mainly focus on? What were the research objectives, especially the wetland meta-analysis studies? Based on these questions, the study lays out research objectives and hypotheses to be tested in the future studies. The future study can undertake a systematic review and meta-analysis on wetland Electronic copy available at: https://ssrn.com/abstract=4185172 valuations studies in the Indian context. It can source studies from the ESVD and Indian EVL tool databases, and literature searches on Scopus, Web of Science, etc. The studies should reflect on the causal linkages, such as wetland area and wetland values, population density and wetland values, etc.
Long-term research on gauged watersheds within the USDA Forest Service’s Experimental Forest and Range (EFR) network has contributed substantially to our understanding of relationships among forests, water, and hydrologic processes and watershed management, yet there is only limited information from coastal forests. This article summarizes key findings from hydrology and water-quality studies based on long-term monitoring on first-, second-, and third-order watersheds on the Santee Experimental Forest, which are a part of the headwaters of the east branch of the Cooper River that drains into the harbor of Charleston, South Carolina. The watersheds are representative forest ecosystems that are characteristic of the low-gradient Atlantic Coastal Plain. The long-term (35-year) water balance shows an average annual runoff of 22% of the precipitation and an estimated 75% for the evapotranspiration (ET), leaving the balance to groundwater. Non-growing season prescribed fire, an operational management practice, shows no effects on streamflow and nutrient export. The long-term records were fundamental to understanding the effects of Hurricane Hugo in 1989 on the water balance of the paired watersheds that were related to vegetation damage by Hugo and post-Hugo responses of vegetation. The long-term precipitation records showed that the frequency of large rainfall events has increased over the last two decades. Although there was an increase in air temperature, there was no effect of that increase on annual streamflow and water table depths. The long-term watershed records provide information needed to improve design, planning, and assessment methods and tools used for addressing the potential impacts of hydrologic responses on extreme events; risk and vulnerability assessments of land use; and climate and forest disturbance on hydrology, ecology, biogeochemistry, and water supply.
This chapter reflects on the most important results presented and their relevance and implications for wetland management and restoration. Overviewing the contents, there are two general areas where this volume will break new ground. The first is the more rigorous underpinning of the two most important regulating wetland ecosystem services, and the second is the presentation and critical discussion of the strong, recent activities in wetland conservation and restoration in China and neighboring countries. The two regulating wetland ecosystem services meant here are (1) the capacity of restored and constructed wetlands to remove nitrogen and phosphorus from through-flowing water and (2) the role of wetlands in cooling or warming the climate as the net balance between carbon sequestration and emissions of methane and nitrous oxide. It is a robust fact that wetlands can be expected to remove 40% of the nitrogen and phosphorus from runoff and groundwater flow in agricultural areas. The area of wetland needed to really make a difference at the catchment level amounts to 10% of the total catchment area. With respect to the cooling/warming function of wetlands, there is now firm evidence that newly originating wetlands start off as having a net warming effect on the climate, because the warming effect of methane emissions surpasses the cooling effects of CO2 sequestration and evapotranspiration. In the course of time, the cooling function will increase due to the persistent cooling of already sequestered carbon. This re-emphasizes the enormous importance of “old” wetlands such as peatlands over newly formed ones in the climate regulation service. On the other hand, climate change effects will enhance the overall primary productivity and carbon sequestration in herbaceous coastal as well as inland wetlands. Increasingly, sea level rise and warming will result in more opportunities for forested wetlands (mangroves, boreal forest), which will enhance the climate cooling service of wetlands worldwide. The book also contains a number of chapters reflecting the large investment in ecological research in wetlands in China and neighboring countries in recent decades. There are chapters on the effects of invasive species on coastal wetlands, on the protection and wise use of coastal wetlands around the Yellow Sea, and on the principles and recent case studies of wetland restoration in this part of the world. The ecosystem services of wetlands definitely play a major role in the motivation and justification of large projects for wetland restoration. The results of these projects so far are most promising.
This introductory chapter defines the key subjects for this volume of ecological studies and briefly presents the common context and the cohesion of the contents of the various chapters. It gives a definition of wetland ecosystem services and outlines briefly the 17 services that have been identified in ecosystems globally and are generally considered as being of major importance. Provisioning wetland ecosystem services such as food chain support, regulating services such as climate cooling, and the enhancement of biodiversity are prime examples. Definitions are also given for wetland character and wise use, as adopted by the Ramsar Convention on Wetlands. New developments in wetland restoration to enhance wetland ecosystem services, as they are described in this volume, are outlined briefly. The overview also pays attention to the chapters on the latest developments of our understanding of water quality enhancement services and climate regulation services of wetlands; on threats and resilience to disturbances such as climate change and invasion of exotic species; on new initiatives for wise use of large, internationally divided wetlands in the Yellow Sea; and on restoration and creation of wetlands in urban environments, in particular in China.