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The Cheadle Center at UCSB manages more than 340 acres of open space between Ellwood Mesa and Goleta Slough, carrying out ecological restoration, research, and education projects at these sites. Characterized by a rich complex of oak woodland, coastal sage scrub, grassland, and wetland ecosystems, the area is known for its relatively high level of biodiversity. The Cheadle Center’s project sites and management areas serve to protect and strengthen the region’s ecology and ecosystems through habitat conservation, upland restoration, wetland creation and enhancement, and the implementation of sustainable stormwater management solutions. Through careful integration with local watersheds and surrounding natural areas, The Cheadle Center's management areas provide an important corridor and refuge for wildlife, ensure the long term preservation of the region's natural resources, and serve as outdoor classrooms, research sites, and recreational areas for the campus community and the public. This archived version of the March 2024 newsletter includes updates on the Ellwood Bioblitz, Spring weeding efforts, Wildflowers, Rare Plants, and the Ocean Meadows Housing Project. The feature story focuses on the presetations and research conducted at Cheadle Center management areas. Community photos include Lesser Scaup (Aythya affinis), Red-breasted Merganser (Mergus serrator), Caspian Tern (Hydroprogne caspia), and more!

The Cheadle Center at UCSB manages more than 340 acres of open space between Ellwood Mesa and Goleta Slough, carrying out ecological restoration, research, and education projects at these sites. Characterized by a rich complex of oak woodland, coastal sage scrub, grassland, and wetland ecosystems, the area is known for its relatively high level of biodiversity. The Cheadle Center’s project sites and management areas serve to protect and strengthen the region’s ecology and ecosystems through habitat conservation, upland restoration, wetland creation and enhancement, and the implementation of sustainable stormwater management solutions. Through careful integration with local watersheds and surrounding natural areas, The Cheadle Center's management areas provide an important corridor and refuge for wildlife, ensure the long term preservation of the region's natural resources, and serve as outdoor classrooms, research sites, and recreational areas for the campus community and the public. This archived version of the March 2024 newsletter includes updates on the NCOS Mesa burn area and Ventura Marsh Milk Vetch. The feature story focuses on the Sierra Madre restoration area. Community photos include Bonaparte's Gull (Chroicocephalus philadelphia), American Bittern (Botaurus lentiginosus), Orange-crowned Warbler (Vermivora celata) and more!

Societal Impact Statement Summary The invasive species S. alterniflora and P. australis are fast growing coastal wetland plants sequestering large amounts of carbon in the soil and protect coastlines against erosion and storm surges. In this global analysis, we found that Spartina and Phragmites increase methane but not nitrous oxide emissions, with Phragmites having a lesser effect. The impact of the invasive species on emissions differed greatly among different types of native plant groups, providing valuable information to managers and policymakers during coastal wetland planning and restoration efforts. Further, our estimated net emissions per wetland plant group facilitate regional and national blue carbon estimates. Globally, Spartina alterniflora and Phragmites australis are among the most pervasive invasive plants in coastal wetland ecosystems. Both species sequester large amounts of atmospheric carbon dioxide (CO2) and biogenic carbon in soils but also support production and emission of methane (CH4). In this study, we investigated the magnitude of their net greenhouse gas (GHG) release from invaded and non‐invaded habitats. We conducted a meta‐analysis of GHG fluxes associated with these two species and related soil carbon content and plant biomass in invaded coastal wetlands. Our results show that both invasive species increase CH4 fluxes compared to uninvaded coastal wetlands, but they do not significantly affect CO2 and N2O fluxes. The magnitude of emissions from Spartina and Phragmites differs among native habitats. GHG fluxes, soil carbon and plant biomass of Spartina‐invaded habitats were highest compared to uninvaded mudflats and succulent forb‐dominated wetlands, while being lower compared to uninvaded mangroves (except for CH4). This meta‐analysis highlights the important role of individual plant traits as drivers of change by invasive species on plant‐mediated carbon cycles. [ABSTRACT FROM AUTHOR]

Marsh terraces, constructed as a restoration and protection strategy, consist of a series of earthen berms in open water areas of the coastal wetland landscape and are being implemented across the Louisiana coast. To assess the efficacy of the marsh terraces as a nature-based solution, a small-scale, high-resolution hydrodynamic model was developed based on field sampling of vegetation and physical parameters (water level, waves, sediment, turbidity, and terrace elevation). This study tested common marsh terrace designs (e.g., chevron, linear, box, T-shape, etc.), ultimately selecting a preferred design based on the evaluation of factors such as vegetation, water depth, and sediment type on terrace stability and sediment retention under calm and storm conditions. The model results revealed that the 100 m box and the chevron designs exhibited greatest terrace stability and sediment trapping, particularly when installed perpendicular to prevailing wind and waves. The preferred terrace design was the box design due to its higher modeled resilience to wind and waves from multiple directions. Vegetation presence enhanced terrace resistance to erosion, with variations depending on vegetation type. Higher vegetation biomass, especially during the summer, contributed to the greatest stability of terraces. Greater water depth between terraces led to increased sediment retention, and terraces predominantly composed of organic-rich mud demonstrated greater stability than those with higher proportions of sand. Overall, vegetation had the greatest impact on sediment retention in the terrace field compared to water depth and sediment type. However, the potential habitat for submerged aquatic vegetation (SAV) was more influenced by water depth (i.e., 0.1 m < depth <1 m) than shear stress (<0.5 Pa). Even under storm conditions, shear stress rarely determined potential habitat for SAV, as shear stress remained relatively low within the terrace field. Potential SAV habitat was most abundant in shallow areas and increased where sediment stability was lowest (i.e., no vegetation and sand), primarily due to eroded sediment increasing the shallow area. While this model was developed using field data specific to Louisiana marshes, it can be adapted as a tool for terrace restoration project design and planning in most coastal wetlands. [ABSTRACT FROM AUTHOR]

Tidal flats, a critical part of coastal wetlands, offer unique ecosystem services and functions. However, in China, these areas are under significant threat from industrialization, urbanization, aquaculture expansion, and coastline reconstruction. There is an urgent need for macroscopic, accurate and periodic tidal flat resource data to support the scientific management and development of coastal resources. At present, the lack of macroscopic, accurate and periodic high-resolution tidal flat maps in China greatly limits the spatio-temporal analysis of the dynamic changes of tidal flats in China, and is insufficient to support practical management efforts. In this study, we used the Google Earth Engine (GEE) platform to construct multi-source intensive time series remote sensing image collection from Sentinel-2 (MSI), Landsat 8 (OLI) and Landsat 9 (OLI-2) images, and then automated the execution of improved MSIC-OA (Maximum Spectral Index Composite and Otsu Algorithm) to process the collection, and then extracted and analyzed the tidal flat data of China in 2018 and 2023. The results are as follows: (1) the overall classification accuracy of the tidal flat in 2023 is 95.19%, with an F1 score of 0.92. In 2018, these values are 92.77% and 0.88, respectively. (2) The total tidal flat area in 2018 and 2023 is 8300.34 km2 and 8151.54 km2, respectively, showing a decrease of 148.80 km2. (3) In 2023, estuarine and bay tidal flats account for 54.88% of the total area, with most tidal flats distribute near river inlets and bays. (4) In 2023, the total length of the coastline adjacent to the tidal flat is 10,196.17 km, of which the artificial shoreline accounts for 67.06%. The development degree of the tidal flat is 2.04, indicating that the majority of tidal flats have been developed and utilized. The results can provide a valuable data reference for the protection and scientific planning of tidal flat resources in China. [ABSTRACT FROM AUTHOR]

Leaf litter in coastal wetlands lays the foundation for carbon storage, and the creation of coastal wetland soils. As climate change alters the biogeochemical conditions and macrophyte composition of coastal wetlands, a better understanding of the interactions between microbial communities, changing chemistry, and leaf litter is required to understand the dynamics of coastal litter breakdown in changing wetlands. Coastal wetlands are dynamic systems with shifting biogeochemical conditions, with both tidal and seasonal redox fluctuations, and marine subsidies to inland habitats. Here, we investigated gene expression associated with various microbial redox pathways to understand how changing conditions are affecting the benthic microbial communities responsible for litter breakdown in coastal wetlands. We performed a reciprocal transplant of leaf litter from four distinct plant species along freshwater‐to‐marine gradients in the Florida Coastal Everglades, tracking changes in environmental and litter biogeochemistry, as well as benthic microbial gene expression associated with varying redox conditions, carbon degradation, and phosphorus acquisition. Early litter breakdown varied primarily by species, with highest breakdown in coastal species, regardless of the site they were at during breakdown, while microbial gene expression showed a strong seasonal relationship between sulfate cycling and salinity, and was not correlated with breakdown rates. The effect of salinity is likely a combination of direct effects, and indirect effects from associated marine subsidies. We found a positive correlation between sulfate uptake and salinity during January with higher freshwater inputs to coastal areas. However, we found a peak of dissimilatory sulfate reduction at intermediate salinity during April when freshwater inputs to coastal sites are lower. The combination of these two results suggests that sulfate acquisition is limiting to microbes when freshwater inputs are high, but that when marine influence increases and sulfate becomes more available, dissimilatory sulfate reduction becomes a key microbial process. As marine influence in coastal wetlands increases with climate change, our study suggests that sulfate dynamics will become increasingly important to microbial communities colonizing decomposing leaf litter. [ABSTRACT FROM AUTHOR]

The partitioning of overall beta diversity into local contributions (LCBD; compositional uniqueness) and species contributions (SCBD) has enhanced the understanding of the organization of metacommunities. Here, we evaluated LCBD and SCBD of aquatic macrophyte metacommunities from 29 subtropical coastal wetlands, covering an extension of 640 km, in Southern Brazil. Furthermore, we assessed the environmental uniqueness, considering both the physical and chemical variables of water in wetlands, as well as climatic variables. We assessed the environmental and spatial correlates of LCBD and the environmental correlates of SCBD. We expected that (i) communities with greater compositional uniqueness would be found in environmentally more unique wetlands, (ii) the compositional uniqueness would also be related to climatic variables that determine the hydrological changes in wetlands, and (iii) the contribution of emergent species to beta diversity would be lower than of floating and submerged species. The compositional uniqueness did not present a clear spatial structure, being positively related to uniqueness in water chemistry and negatively to the mean air temperature during the driest quarter. The species contribution to beta diversity was higher for floating species than for emergent ones. Moreover, SCBD correlated to climatic variables and presented a positive relationship with site occupation, suggesting that more frequent species in terms of site occurrence contribute most to beta diversity. Our results show the importance of local environmental and broader climatic predictors in determining the compositional uniqueness of macrophyte communities and species contributions to overall beta diversity in the coastal wetlands of Southern Brazil. [ABSTRACT FROM AUTHOR]

In approximately one decade, global temperatures will likely exceed a warming level that a United Nations Intergovernmental Panel on Climate Change report considers a "red alert for humanity". We propose exploring tidal flat diatoms to address climate change challenges. Tidal flats are extensive coastal ecosystems crucial to the provisioning and regulation of aquatic environments. Diatoms contribute to tidal flat biomass production and account for 20% of global primary productivity and 40% of annual marine biomass production, making them crucial for nutrient cycling and sediment stabilization. Potential CO2 removal from Korean tidal flats by diatoms is estimated to be 598,457–683,171 t CO2 equivalents (CO2e) annually, with the economic value of blue carbon (BC) resulting from diatom activity being approximately US$ 17.95–20.50 million. Dissemination of this potential could incentivize coastal wetland protection and climate change mitigation measures. The global estimated CO2e removal potential of tidal flat diatoms is 40,957,346–46,754,961 t CO2e, representing 0.11–0.13% of the annual global greenhouse gas emissions, even though tidal flats cover 0.0025% of the Earth's surface and diatoms represent less than 0.5% (by weight) of all photosynthetic plants. Researchers should combine ecology and economics to develop standardized approaches for carbon input monitoring and quantification. Further, spatiotemporal analyses of environmental threats to tidal flat diatoms are necessary for conserving their biodiversity and function as a critical BC source. Land-based cultivation for large-scale biomass production and biorefinery processes can contribute to a greener, more prosperous future for humanity and the marine ecosystems upon which we rely. [ABSTRACT FROM AUTHOR]

Coastal tidal wetlands are crucial for environmental and economic health, but facing threats from various environmental changes. Detecting changes of tidal wetlands is essential for promoting sustainable development in coastal areas. Despite extensive researches on tidal wetland changes, persistent challenges still exist. Firstly, the high similarity among tidal wetland types hinders the effectiveness of existing common indices. Secondly, many current methods, relying on hand-crafted features, are time-consuming and subject to personal biases. Thirdly, few studies effectively integrate multi-temporal and semantic information, leading to misinterpretations from environmental noise and tidal variations. In view of the abovementioned issues, we proposed a novel temporal-spectral-semantic-aware convolutional transformer network (TSSA-CTNet) for multi-class tidal wetland change detection. Firstly, to address spectral similarity among different tidal wetlands, we proposed a sparse second order feature construction (SSFC) module to construct more separable spectral representations. Secondly, to get more separable features automatically, we constructed temporal-spatial feature extractor (TSFE) and siamese semantic sharing (SiamSS) blocks to extract temporal-spatial-semantic features. Thirdly, to fully utilize semantic information, we proposed a center comparative label smoothing (CCLS) module to generate semantic-aware labels. Experiments in the Greater Bay Area, using Landsat data from 2000 to 2019, demonstrated that TSSA-CTNet achieved 89.20% overall accuracy, outperforming other methods by 3.75%–16.39%. The study revealed significant area losses in tidal flats, mangroves, and tidal marshes, decreased by 3148 hectares, 35 hectares, and 240 hectares, respectively. Among the cities in GBA, Zhuhai shows the most significant area loss with a total of 1626 hectares. TSSA-CTNet proves effective for multi-class tidal wetland change detection, offering valuable insights for tidal wetland protection. [ABSTRACT FROM AUTHOR]

Coastal restoration projects are significantly important in coastal ecosystems as wetland losses accelerate. This study investigates tidal hydrodynamics and the potential impacts of a waterway opening on an existing roadway to restore and revitalise salt marshes in a small estuarine system in Virginia, USA. A depth-integrated, discontinuous Galerkin shallow-water equations model (DG-SWEM) is applied for astronomic tide simulation. The model employs a high-resolution unstructured mesh with a minimum element size of less than one meter and resolves complex tidal flows in the entire barrier island system, including the existing culvert gate and canal system. Compared to the existing system, the water exchange increased dramatically (flushing time also dramatically decreased) under the opened scenarios regardless of the opening width (22.9-, 30.5-, and 38.1-m width). By increasing the opening width, peak velocity through the proposed opening decreased 30–40%, and the maximum shear stress was reduced by more than half. The high-resolution model represented complex tidal flows, including eddies, and assisted in striking a balance of water-exchange capability, opening stability, and minimising their potential erosions for the opening design. Besides, erosion and sediment transport potentials for suspended sediments were estimated using bed shear stress and a Lagrangian particle tracking module. Such proxy modelling approach allows for the impact assessment of civil engineering and ecological waterworks in complex and highly damped tidal flow areas and is readily transferrable to other like systems (e.g. causeway construction, causeway cutting, biota passageways, and inlet modification). [ABSTRACT FROM AUTHOR]

Mangroves are one coastal ecosystem that has experienced a long history of fragmentation and loss by urbanization. Yet, these small mangroves in urban areas are often missing from current wetland inventory due to lower resolution mapping methods and size classifications that may overlook these mangroves in highly urbanized areas. We mapped mangroves along a gradient of urbanization in Miami-Dade County, Florida (MDC) by combining several landcover databases, high-resolution imagery, and ground-truthing. We compared our newly mapped mangrove dataset with the Florida Fish and Wildlife Conservation Commission’s (FWC) current mangrove habitat dataset. We quantified differences in mangrove area, fragmentation metrics, and shape complexity across three urban intensities within MDC and between the datasets. We identified an additional 386 mangrove patches that were missed by the FWC map. The majority of these newly found mangroves were in the most urban regions of MDC. We identified average mangrove stand size in the least urbanized region is about 29 times bigger than those found in the most urbanized region. We also found that the FWC dataset significantly overestimated average mangrove stand size (18.32-ha) compared to the newly mapped mangrove dataset (1.43-ha) in the most urbanized region. Our results demonstrate that large scale wetland mapping efforts, like those of state agencies, provide valuable mangrove area estimations but may miss key fragmentation patterns by not including smaller mangrove stands scattered throughout highly urbanized regions. Habitat maps that capture these smaller, fragmented mangroves are needed to evaluate how urbanization shapes mangrove extent and ecosystem function. [ABSTRACT FROM AUTHOR]

Wetlands, widely distributed and hotspots of biodiversity, play a crucial role in global biogeochemical cycles and human well-being. However, despite their ecological importance, wetlands worldwide are under threat due to widespread conversion into agricultural fields, leading to changes in hydrology, increased salinity, and more frequent eutrophication. In response to these challenges, constructed wetlands are created to treat agricultural wastewater and mitigate eutrophication. This study aims to assess the effect of natural vs. constructed wetlands on ecosystem functioning (organic matter decomposition of the dominant vegetation: Phragmites australis and Typha angustifolia). We conducted this study in the Ebro River Delta (NE Spain), which represents a deltaic wetland affected by agricultural land-use changes, examining two constructed and two natural wetlands. Our findings indicate that the influence of agricultural runoff on the decomposition process was similar in both types of wetlands, suggesting that freshwater agricultural runoff has a consistent effect on ecosystem functioning, regardless of its origin, natural vs. constructed. Differences in macroinvertebrate communities associated with leaf litter were likely due to specific conductivity but did not impact decomposition rates. The estimated time required to decompose 95% of the T. angustifolia litter produced annually in the studied wetlands ranged from 288 to 856 days. In constructed wetland, this decomposition time exceeded one year, contributing to soil formation and carbon sequestration in wetland ecosystems. Our study suggests that the utilization of constructed wetlands for treating agricultural runoff can aid in mitigating the impacts of agricultural land use in these areas. [ABSTRACT FROM AUTHOR]

With rapid climate warming, some coastal high‐latitude ecosystems are experiencing more frequent tidal floods. Yet little is known about tundra plant‐community responses to flooding, and whether Arctic warming may modulate such responses. In a 2‐year, full‐factorial field experiment in coastal tundra wetlands of the Yukon‐Kuskokwim (Y‐K) Delta (western Alaska), we simulated periodic tidal flood events at two severities under both ambient and warmed summer conditions and measured above‐ground plant‐community responses. Low‐severity flooding represented overbank flooding 1 day per month, which is consistent with projections in the next 5 years. High‐severity flooding represented a more impactful flooding regime (three consecutive days per month) that is projected to occur in the next 10 years. Our warming treatment (+1°C) also represented a change projected in the next 10 years. Regardless of temperature, high‐severity flooding increased graminoid biomass by >45%, in turn increasing live plant‐community biomass by >18%. Low‐severity flooding had similar, though weaker, effects. Flooding had overall negative effects on both forb and shrub biomass, though shrub responses were weaker. Only during the second summer, warming increased graminoid biomass by 20% and tended to increase shrub biomass, regardless of flooding. Concurrently, warming enhanced standing‐dead graminoid biomass by 20%, while high‐severity flooding decreased it by 15%. Therefore, wet tundra that was both flooded and warmed had the greatest proportion of graminoids and total live biomass, but standing‐dead biomass comparable to that of unmanipulated wet tundra. Synthesis. While our manipulations simulated flooding and warming regimes expected in the wetlands of the Y‐K Delta over the same, near‐future (5‐to‐10 years) time frame, flooding had stronger effects than warming. What is striking is the rate at which graminoid increases occurred, becoming apparent after only two monthly flood events in the first experimental year. Flooding‐induced decreases in standing‐dead biomass suggests that the incorporation of dead plant material into the litter layer might be facilitated by tidal floods. These rapid increases in plant biomass and potentially biomass turnover, especially of graminoids, which are characterized by high‐quality litter, may have major implications for carbon and nutrient cycling of more frequently flooded coastal ecosystems in a warmer Arctic. [ABSTRACT FROM AUTHOR]

The article explores the relationship between water quality and vulnerabilities faced by small-scale fishery communities in Chilika Lagoon, India. It discusses the impact of invasive shrimp aquaculture activities and hydrological interventions on water quality and fish populations, as well as the social and economic vulnerabilities in the small-scale fisheries system. The study aims to bridge the gap in understanding the role of water quality in vulnerability analysis and provides insights into coping responses and adaptive capacity for sustainable small-scale fisheries. The Chilika Lagoon has faced challenges such as pollution, biodiversity loss, and employment insecurity, leading to ecological, social, economic, institutional, and technological vulnerabilities for fishing communities. The text also discusses coping and adaptation strategies employed by these communities, the use of mobile phones and ICT tools in fisheries, and the importance of protecting water quality and implementing adaptation measures. The given document is a list of references and citations from various sources related to climate change, social vulnerability, and fishing communities in the Chilika Lagoon in India. These sources provide valuable information for researchers interested in understanding the impacts of climate change on fishing-dependent communities and the measures taken to address these challenges. The given text is a list of references and citations from various sources related to the topic of small-scale fisheries in the Chilika Lagoon in India. These sources cover a range of topics including social-ecological regime shifts, water quality, biodiversity, climate change, and the impact of human activities on the lagoon. They provide valuable information for [Extracted from the article]

Climate change and invasive species represent two intertwined global environmental challenges profoundly affecting freshwater ecosystems. This study uses Ecological Niche Modeling along with risk screening to delve into the preferences and potential distribution of Potamopyrgus antipodarum, an invasive species, in relation to climate zones and habitat types, shedding light on the critical importance of coastal wetlands and high soil organic carbon content in shaping habitat suitability. Our findings underscore that P. antipodarum exhibits a distinct affinity for cool temperate, moist climates, as well as temperate floodplain rivers, wetlands, and coastal areas. Notably, coastal wetlands, endowed with elevated soil organic carbon levels, emerged as pivotal habitats for this species. Projections indicated a significant expansion in North America, potentially extending into South America. Türkiye reveals an intriguing alignment between its habitat and the natural distribution areas of P. antipodarum, presenting potential for habitat contraction while still retaining a broader range compared to other regions. These potential expansions were predominantly driven by climate suitability, playing a pivotal role in the invasiveness of P. antipodarum, with anticipated future climate regimes exerting substantial influence on its dispersal capabilities. [ABSTRACT FROM AUTHOR]

Coastal wetland ecosystems are critical due to their diverse ecological and economic benefits, yet they have been significantly affected by human activities over the past century. Understanding the spatiotemporal changes and underlying factors influencing these ecosystems is crucial for developing effective ecological protection and restoration strategies. This study examines the Tianjin–Hebei coastal wetlands using topographic maps from the 1940s and Landsat satellite imagery from 1975, 2000, and 2020, supplemented by historical literature and field surveys. The aim is to analyze the distribution and classification of coastal wetlands across various temporal intervals. The findings indicate an expansion of the Tianjin–Hebei coastal wetlands from 7301.34 km2 in the 1940s to 8041.73 km2 in 2020. However, natural wetlands have declined by approximately 44.36 km2/year, while constructed wetlands have increased by around 53.61 km2/year. The wetlands have also become increasingly fragmented, with higher numbers of patches and densities. The analysis of driving factors points to human activities—such as urban construction, cultivated land reclamation, sea aquaculture, and land reclamation—as the primary contributors to these changes. Furthermore, the study addresses the ecological and environmental issues stemming from wetland changes and proposes strategies for wetland conservation. This research aims to enhance the understanding among researchers and policymakers of the dynamics and drivers of coastal wetland changes, as well as the major challenges in their protection, and to serve as a foundation for developing evidence-based conservation and restoration strategies. [ABSTRACT FROM AUTHOR]

Introduction: The emergence of voluntary carbon markets is creating new opportunities to sustainably finance Natural Climate Solution (NCS) projects. In Australia, the federal government recently enacted the Tidal Restoration of Blue Carbon Ecosystems Methodology Determination 2022 (Tidal Reconnection Method), whereby restoration activities that reintroduce tidal flows to allow the re-establishment of coastal wetland (blue carbon) ecosystems, through the removal or modification of a tidal restriction, can be used to gain and sell Australian carbon credit units. Australia has the highest net blue carbon wealth in the world, with 5%-11% of global carbon stocks, yet there is currently a lack of large-scale feasibility assessments and supporting methodologies to identify and prioritise sites with the greatest potential for NCS project implementation to help inform investment decisions. Methods: In this study, we applied a spatial Multi-Criteria Decision Analysis (MCDA) to identify, map, and prioritise potential sites for blue carbon coastal wetland restoration in South Australia that meet criteria outlined in the Tidal Reconnection Method. This study compared information on 1) predicted flooding extent following tidal reconnection and under sea level rise (SLR; present-day, 2050 and 2,100); 2) project implementation complexity (e.g. who possesses land tenure); and 3) carbon sequestration potential through predicted area of vegetation change under the above SLR scenarios. Results: Our results identified 64 sites of interest, of which 32 received an overall "high" prioritisation score of 3 or more out of 5. This equates to approximately 21,114 ha of high priority potential blue carbon restoration sites. Discussion: The MCDA enables development of a portfolio of viable restoration projects through a rapid "desktop" prioritisation of sites of interest, which can then guide investment in further detailed cost/benefit feasibility assessments. This study demonstrates an adaptable MCDA approach to map potential NCS projects at meaningful spatial scales and in-line with carbon market-based opportunities. [ABSTRACT FROM AUTHOR]

Marsh and mangrove forest habitats are productive at capturing and storing carbon, thus actions to protect and create coastal blue carbon sinks could help mitigate global warming. Dredged material is often used to create coastal habitats and evaluating the carbon impact of placement alternatives (PA) could help inform restoration and climate policies. Output from a Delft3D‐FM morphodynamics and hydrodynamics model informed a Coastal Wetlands Carbon Model at years 2020, 2025, 2030, and 2050. Three model simulations were used and included (1) no restoration (PA1), (2) restoration dominated with mangroves (PA2), and (3) restoration dominated with marshes (PA3) at a different location. Habitats of brackish marsh, saline marsh, mangrove forest, and saline open water that surround Port Fourchon, Louisiana, U.S.A., were evaluated to estimate the net greenhouse gas (GHG) flux of the study area with and without restoration. In years 2020 and 2025, the study area was estimated to be a net GHG sink (−1.1 ± 0.2 MMT CO2e) with or without mangrove and marsh‐dominated restoration. At years 2030 and 2050, even with habitat loss due to sea‐level rise, the study area for all simulations was projected to remain a net GHG sink. At year 2050, +0.1 ± 0.04 MMT CO2e could be avoided with restoration. At the restoration project scale, mangrove‐dominated restoration (PA2) had net GHG sinks (−0.07 to −0.09 MMT CO2e) near the marsh‐dominated restoration (PA3, −0.09 to −0.13 MMT CO2e). Thus, these modeled results could help inform future restoration planning and climate policies. [ABSTRACT FROM AUTHOR]

Large grazers modify vegetated ecosystems and are increasingly viewed as keystone species in trophic rewilding schemes. Yet, as their ecosystem influences are context‐dependent, a crucial challenge is identifying where grazers sustain, versus undermine, important ecosystem properties and their resilience. Previous work in diverse European saltmarshes found that, despite changing plant and invertebrate community structure, grazers do not suppress below‐ground properties, including soil organic carbon (SOC). We hypothesised that, in contrast, eastern US saltmarshes would be sensitive to large grazers as extensive areas are dominated by a single grass, Spartina alterniflora. We predicted that grazers would reduce above‐ and below‐ground Spartina biomass, suppress invertebrate densities, shift soil texture and ultimately reduce SOC concentration. We tested our hypotheses using a replicated 51‐month large grazer (horse) exclusion experiment in Georgia, coupled with observations of 14 long‐term grazed sites, spanning ~1000 km of the eastern US coast. Grazer exclusion quickly led to increased Spartina height, cover and flowering, and increased snail density. Changes in vegetation structure were reflected in modified soil texture (reduced sand, increased clay) and elevated root biomass, yet we found no response of SOC. Large grazer exclusion also reduced drought‐associated vegetation die‐off. We also observed vegetation shifts in sites along the eastern US seaboard where grazing has occurred for hundreds of years. Unlike in the exclusion experiment, long‐term grazing was associated with reduced SOC. A structural equation model implicated grazing by revealing reduced stem height as a key driver of reduced soil organic carbon. Synthesis: These results illustrate the context dependency of large grazer impacts on ecosystem properties in coastal wetlands. In contrast to well‐studied European marshes, eastern US marshes are dominated and structured by a single foundational grass species resulting in vegetation and soil properties being more sensitive to grazing. Coastal systems characterised by a single foundation species might be inherently vulnerable to large grazers and lack resilience in the face of other disturbances, underlining that frameworks to explain and predict large grazer impacts must account for geographic variation in ecosystem structure. [ABSTRACT FROM AUTHOR]

Burullus, a highly enclosed wetland at the mouth of the River Nile, receives biogenic elements primarily from the Nile River and serves as an ideal area for studying how changes in the watershed, particularly since the construction of the Aswan Dam, have impacted the estuarine lakes' environment. This study aimed to reveal the differences in nutrient salt levels in the estuarine lakes before and after the Aswan Dam's construction, as well as addressing the effects of these changes on the ecological environment through 210Pb dating of Burullus Lagoon B1 cores, combined with testing and analyzing the total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), and biogenic silica (BSi), alongside the historical data. The results showed that sedimentary TOC, TN, and TP contents generally increased from bottom to top. This indicates that despite the significant reduction in nutrient fluxes due to the Aswan Dam, nitrogen (N) and phosphorus (P) concentrations in downstream lakes did not decrease owing to the substantial increase in N and P inputs from human discharges downstream, and that sedimentary TN/TP ratios were all below 16, suggesting that the lakes remained phosphorus-limited. While, the biogenic silica (BSi) and the BSi/TOC ratio both showed a decreasing trend from bottom to top, indicating that the reduction of water and sediment caused by the Aswan Dam has led to a decline in diatom biomass and their overall contribution to primary productivity in the wetland, suggesting that the ecological environment may deteriorate over time. [ABSTRACT FROM AUTHOR]

Coastal wetlands play an important role in the health of local, regional and global ecosystems through climate change mitigation and biodiversity conservation. As a result of human activities, climate change and invasive alien species, coastal wetland ecosystems in some areas of China are facing a crisis of impaired ecosystem functions and declining biodiversity. Remote sensing technology has been widely used in the restoration of coastal wetland ecosystems over the past 30 years because of its unique advantages such as wide observation range, fast access to information, large amount of information and high comparability of information. This work presents a visual analysis of the literature on the application of remote sensing technology in coastal wetland restoration based on bibliometrics. Our analysis shows that the application of remote sensing technology in coastal wetland ecology originated in 1993 and entered a period of rapid development until 2008, with a significant increase in the number of publications in the last three years. In 2010, China surpassed the US for the first time in the field of coastal wetland remote sensing technology, jumping to the first place. Among the major research institutions, the Chinese Academy of Sciences had the highest number of publications, followed by the US Geological Survey and East China Normal University. Keyword clustering analysis shows that research on coastal wetland ecosystem evolution, drivers and restoration, coastal marsh wetland ecology, water body information inversion, vegetation parameter inversion and remote sensing technology are the main research hotspots at present. In the future, China should further strengthen the research on the response and adaptation of coastal wetland ecosystems in the context of global climate change, and reveal the differences in response and adaptation of coastal wetlands at different temporal a nd spatial scales. At the same time, in the face of increasingly severe challenges such as climate change, we should respond flexibly to local pressures and develop relevant policies for local monitoring and feedback related to management actions. Establish a coastal wetland monitoring network to regularly collect and analyse data, and use big data and decision-making tools to quickly make corrections to plans. [ABSTRACT FROM AUTHOR]

Coastal‐wetlands play a crucial role as carbon (C) reservoirs on Earth due to their C pool composition and functional sink, making them significant for mitigating global climate change. However, due to the development and utilization of wetland resources, many wetlands have been transformed into other land‐use types. The current study focuses on the alterations in soil organic‐C (SOC) in coastal‐wetlands following reclamation into aquaculture ponds. We conducted sampling at 11 different coastal‐wetlands along the tropical to temperate regions of the China coast. Each site included two community types, one with solely native species (Suaeda salsa, Phragmites australis and Mangroves) and the other with an adjacent reclaimed aquaculture pond. Across these 11 locations we compared SOC stock, active OC fractions, and soil physicochemical properties between coastal wetlands and aquaculture ponds. We observed that different soil uses, sampling sites, and their interaction had significant effects on SOC and its stock (p <.05). Reclamation significantly declined SOC concentration at depths of 0–15 cm and 15–30 cm by 35.5% and 30.3%, respectively, and also decreased SOC stock at 0–15 cm and 15–30 cm depths by 29.1% and 37.9%, respectively. Similar trends were evident for SOC stock, labile organic‐C, dissolved organic‐C and microbial biomass organic‐C concentrations (p <.05), indicating soil C‐destabilization and losses from soil following conversion. Soils in aquaculture ponds exhibited higher bulk density (BD; 11.3%) and lower levels of salinity (61.0%), soil water content (SWC; 11.7%), total nitrogen (TN) concentration (23.8%) and available‐nitrogen concentration (37.7%; p <.05) than coastal‐wetlands. Redundancy‐analysis revealed that pH, BD and TN concentration were the key variables most linked with temporal variations in SOC fractions and stock between two land use types. This study provides a theoretical basis for the rational utilization and management of wetland resources, the achievement of an environment‐friendly society, and the preservation of multiple service functions within wetland ecosystems. [ABSTRACT FROM AUTHOR]

The article discusses the lack of attention and protection given to wetlands in Latin America, particularly the wetlands of the Paraná Delta River. Wetlands are important ecosystems that serve as fresh water reservoirs and support a significant amount of biodiversity. However, 59% of Latin American wetlands are deteriorating, making it the region with the highest rate of wetland deterioration. The article highlights the recent events in Argentina where an influx of capybaras in a residential area brought attention to the environmental consequences of receding wetlands. The capybaras became a symbol of resistance and sparked a movement for the protection of wetlands. The article also introduces the concept of "wetland poetics," which refers to poetic expressions that engage with the specificities of wetland environments and contribute to environmental preservation. The article analyzes the works of three poets who explore wetlands within Argentina and emphasizes the importance of regional and ecological perspectives in understanding and addressing environmental challenges. The text discusses the work of Natalia Garay, a poet and visual artist from Paraná, Argentina, who explores wetland poetics and regional identity. Garay's poem "Smoke Altar" examines the impact of industrial ranching and intentional fires on the wetlands, portraying the pollution as disrupting social relations and likening people to livestock. The poem also highlights the erasure of Indigenous conceptions of the landscape and calls for the restoration of the wetlands. The text also mentions Mario Castells, another poet whose work addresses [Extracted from the article]

Salt-sensitive trees in coastal wetlands are dying as forests transition to marsh and open water at a rapid pace. Forested wetlands are experiencing repeated saltwater exposure due to the frequency and severity of climatic events, sea-level rise, and human infrastructure expansion. Understanding the diverse responses of trees to saltwater exposure can help identify taxa that may provide early warning signals of salinity stress in forests at broader scales. To isolate the impacts of saltwater exposure on trees, we performed an experiment to investigate the leaf-level physiology of six tree species when exposed to oligohaline and mesohaline treatments. We found that species exposed to 3–6 parts per thousand (ppt) salinity had idiosyncratic responses of plant performance that were species-specific. Saltwater exposure impacted leaf photochemistry and caused early senescence in Acer rubrum, the most salt-sensitive species tested, but did not cause any impacts on plant water use in treatments with <6 ppt. Interestingly, leaf spectral reflectance was correlated with the operating efficiency of photosystem II (PSII) photochemistry in A. rubrum leaves before leaf physiological processes were impacted by salinity treatments. Our results suggest that the timing and frequency of saltwater intrusion events are likely to be more detrimental to wetland tree performance than salinity concentrations. [ABSTRACT FROM AUTHOR]

The distribution of vegetation in coastal wetlands is significantly influenced by soil properties. However, the mechanisms of how soil characteristics impact the physiological processes of Tamarix chinensis forests remain underexplored. This study examined changes in the soil physicochemical properties and structural attributes of natural T. chinensis forests in the Yellow River Delta with increasing distance from the shoreline. T. chinensis trees were classified into healthy, intermediate, and dying categories based on growth potential, and dynamic changes in salt ions and non-structural carbohydrates (NSCs) were investigated. Results indicated that increasing distance from the shoreline corresponded to decreased soil salinity and pH, and increased soil moisture. T. chinensis mortality rate decreased, while tree height and ground diameter increased with distance. Soil salt content was positively correlated with T. chinensis mortality, but negatively correlated with tree height and ground diameter. Trees with lower growth potential had higher Na+ but lower K+ and K+/Na+ ratio. Soil salt content was positively correlated with root and stem Na+, while soil moisture was positively correlated with leaf NSCs. These findings suggest that soil salt content and moisture significantly influence T. chinensis ion absorption and NSC accumulation, with sodium toxicity being a key factor in the spatial distribution of T. chinensis forests. [ABSTRACT FROM AUTHOR]

Given global climate change and rapid land cover changes due to human activities, accurately identifying, extracting, and monitoring the long-term evolution of wetland resources is profoundly significant, particularly in areas with fragile ecological conditions. Gansu Province, located in northwest China, contains all wetland types except coastal wetlands. The complexity of its wetland types has resulted in a lack of accurate and comprehensive information on wetland changes. Using Gansu Province as a case study, we employed the GEE platform and Landsat time-series satellite data, combining high-quality sample datasets with feature-optimized multi-source feature sets. The random forest algorithm was utilized to create wetland classification maps for Gansu Province across eight periods from 1987 to 2020 at a 30 m resolution and to quantify changes in wetland area and type. The results showed that the wetland mapping method achieved robust classification results, with an average overall accuracy (OA) of 96.0% and a kappa coefficient of 0.954 across all years. The marsh type exhibited the highest average user accuracy (UA) and producer accuracy (PA), at 96.4% and 95.2%, respectively. Multi-source feature aggregation and feature optimization effectively improve classification accuracy. Topographic and seasonal features were identified as the most important for wetland extraction, while textural features were the least important. By 2020, the total wetland area in Gansu Province was 10,575.49 km2, a decrease of 4536.86 km2 compared to 1987. The area of marshes decreased the most, primarily converting into grasslands and forests. River, lake, and constructed wetland types generally exhibited an increasing trend with fluctuations. This study provides technical support for wetland ecological protection in Gansu Province and offers a reference for wetland mapping, monitoring, and sustainable development in arid and semi-arid regions. [ABSTRACT FROM AUTHOR]

Considering the importance of coastal wetlands as key land resources and the ecological degradation caused by large-scale and multi-stage reclamation, as well as the significant synergistic and superimposed effects of reclamation on wetland degradation in temporal and spatial dimensions, it is vital to conduct in-depth research on the impact mechanisms and cumulative effects of reclamation on wetland degradation. However, the existing methods for evaluating these cumulative effects still have some shortcomings in characterizing the spatiotemporal scale. Consequently, it is urgent to introduce or develop a cumulative effect evaluation method based on remote sensing. Taking the Jiangsu coastal wetland as a typical case study area, the present study constructed a cumulative effect evaluation method based on calculus theory combined with landscape succession modeling and statistical analysis. This method was then used to quantitatively analyze the impacts and cumulative effects of reclamation on wetland degradation in the Jiangsu coastal region from 1980 to 2024. The results show that degradation of the Jiangsu coastal wetlands over the last 45 years covered 2931.54 km2, accounting for 46.92% of the area in 1980. This degradation primarily reflects a shift from natural wetland to constructed wetland. In addition, the reclaimed area of 2119.61 km2 is mainly used for aquaculture and agricultural cultivation. The reclamation rate of Jiangsu showed insignificant fluctuations and significant spatial differences. The reclamation rate of the north counties and cities presented a downward trend, while that of the south counties and cities presented an upward trend. Reclamation has a significant impact on wetland degradation, with a contribution rate of 50.62%. The cumulative effect in the study area reached its maximum value in 2015, except for Nantong City. This study provides a new perspective for quantitatively analyzing the impacts and cumulative effects of coastal wetland reclamation and provides guidance for the effective management and sustainable utilization of coastal wetland resources. [ABSTRACT FROM AUTHOR]

Coastal wetlands are one of the most threatened ecosystems due to, firstly, their relative rarity and, secondly, the strong human interest in these coastal sites for infrastructure development, and recreation. These coastal wetlands also serve as important migration stopover sites for a range of waterbirds. There is great international interest in mitigating the negative effects of human land development and in restoring degraded habitats. I evaluated the response of one waterbird community to the mitigation action implemented during road expansion in an important waterbird coastal habitat in central Norway. Using a novel mitigation method, the shoreline was moved seawards to allow space for a continued shoreline habitat and the extended road. By weekly monitoring the waterbird community during spring and autumn migration periods (n = 7 of each), I found similar biodiversity, evenness, and abundance of geese, dabbling ducks, diving ducks, gulls, and waders when data for the whole wetland were used. However, after construction waders were partially displaced from the zone closest to the road to a zone further away. For some groups of birds, shoreline translocation can be a fruitful mitigation action aiming to reduce the negative effects of infrastructure expansion in coastal areas. [ABSTRACT FROM AUTHOR]

Developing accurate landscape‐scale aboveground biomass (AGB) maps is critical to understanding coastal deltaic wetland resilience, as AGB influences stability and elevation dynamics in herbaceous wetlands. Here we used AVIRIS‐NG imaging spectrometer (or "hyperspectral") data from NASA's 2021 Delta‐X mission in coastal Louisiana to map seasonal changes in herbaceous AGB across two deltaic basins with contrasting sediment delivery and hydrologic regimes: the Atchafalaya (active) and Terrebonne (inactive). We assessed the impact of atmospheric effects on our retrievals, as high water vapor content in August 2021 caused significant noise in the 880–1,000 and 1,080–1,200 nm near‐infrared (NIR) wavelengths. We hypothesized that correcting these wavelengths with our conditional Gaussian interpolation algorithm would improve AGB estimates due to their association with plant canopy water content. We empirically assessed the performance of the corrected spectra on AGB estimates using Partial Least Squares Regression (PLSR), finding that the corrected NIR bands attained high variable importance and reduced estimation errors. Our Random Forest regression approach based on the corrected spectra attained equivalent error metrics via leave‐one‐out‐cross‐validation as the PLSR models (R2 = 0.43, mean absolute error = 257.3 g/m2) while greatly improving the AGB maps' visual quality, having better captured variability while reducing noise and discontinuities in AGB estimates across flightlines. The maps show differing seasonal growth, with the Atchafalaya and Terrebonne Basins' AGB increasing from means of 4.3–9.4 and 4.6–8.9 Mg/ha, respectively. We demonstrated that imaging spectroscopy can be applied to assess herbaceous biomass stocks, growth patterns, and resilience in coastal ecosystems. Plain Language Summary: Developing accurate landscape‐scale aboveground biomass (AGB) maps is critical to understanding the sustainability of coastal deltaic systems, as plant biomass aids in a wetland maintaining its elevation in the face of relative sea level rise. Here we use imaging spectroscopy, or "hyperspectral" remote sensing, to map wetland biomass across seasons in coastal Louisiana. In doing so, we correct for the noise caused by high atmospheric water vapor content in important infrared bands, thereby improving our biomass models. We test empirical and machine learning models for estimating wetland biomass, determining that a machine learning regression model using our corrected data delivers the best model metrics and map quality. We thus map AGB in April and August 2021, across the Atchafalaya and Terrebonne Basins. Our maps show various seasonal growth patterns, with the Atchafalaya and Terrebonne Basins' herbaceous AGB increasing from means of 4.3–9.4 and 4.6–8.9 Mg/ha, respectively. Key Points: We developed an interpolation algorithm to correct noise in near‐infrared bands that improved wetland aboveground biomass (AGB) estimatesWe assessed model approaches and mapped wetland AGB in coastal Louisiana with a machine learning algorithm for March and August 2021The active Atchafalaya and inactive Terrebonne Basins' AGB increased from means of 4.3–9.4 and 4.6–8.9 Mg/ha, respectively [ABSTRACT FROM AUTHOR]

Coastal marsh ecosystems are changing and being lost at a rapid rate around the world. One of the fastest rates of land loss, specifically coastal marsh habitat, occurs in Louisiana on the Northern Gulf Coast of the USA. To address this issue, state and federal agencies have undertaken massive wetland restoration efforts to preserve and restore coastal marsh habitats in Louisiana. For these efforts to be successful in the long-term, it is critical to understand what methodologies and techniques result in resilient restoration projects. However, traditional methods to monitor restoration success rely on labor intensive field measurements that are often limited in scope, difficult to maintain, and underfunded. Recent technological developments with uncrewed aircraft systems (UASs) and image processing have substantially improved the ability of restoration practitioners to use off-the-shelf UASs and cameras to map projects. We present a streamlined method using a commercially available drone with a high-resolution red, green, blue (RGB) camera to assess the effects of wetland restoration and integrate more modern tools into evaluation approaches. We conducted drone flights at restored brackish marshes of various ages using a space for time substitution with the goal of understanding the long-term success of marsh restoration. We observed that created marshes had higher land to water ratios than natural marshes. This finding suggests that these restored areas were gaining and maintaining elevation after approximately 10 years. Our method shows that drone surveys offer low-cost, minimally invasive methods for evaluating restored wetlands and ultimately tell us more about ecosystem function through realistic site-level habitat configurations. [ABSTRACT FROM AUTHOR]

Foundation species support highly productive and valuable ecosystems, but anthropogenic disturbances and environmental changes are increasingly causing foundation species shifts, where one foundation species replaces another. The consequences of foundation shifts are not well understood, as there is limited research on the equivalency of different foundation species and the functions they support. Here, we provide insight into community-level consequences of foundation shifts in the Gulf of Mexico, where the typical marsh foundation species (Spartina alterniflora) is being replaced with a mangrove foundation species (Avicennia germinans), forcing marsh fauna to rely on Avicennia for foundational support. We evaluated the interactions of two common and ecologically valuable basal consumers, fiddler crabs (Uca spp.) and marsh periwinkle snails (Littoraria irrorata), with both foundation species across sites with different levels of mangrove encroachment. By investigating both physical support, measured as habitat association and co-occurrence, and trophic support, as basal resource diet contributions, we found that Avicennia can physically replace Spartina for some consumers, but is not providing equivalent trophic support. Uca and Littoraria commonly occupy encroached sites and associate with mangroves but incorporate almost no mangrove plant matter into their diets. The ultimate consequences of a foundation shift in the case of mangrove encroachment may include shifting energy flows and resource use and decreased populations of basal consumers. Looking at interactions with foundation species from multiple perspectives is necessary to obtain a complete picture of the effects that foundational shifts are having, especially as such shifts are becoming increasingly common. [ABSTRACT FROM AUTHOR]

Yancheng coastal wetland, the largest coastal wetland in the west coast of the Pacific Ocean and the margin of the Asian continent, has significant environmental, economic and social effects on local human beings. The extensive contamination and potential risk of quinolone antibiotics (QNs) on local aquaculture and human health are still not clear until now. In this study, 52 surface sediment samples were collected to investigate the contamination status and polluted sources, and evaluate ecological risks of QNs in the south of Yancheng coastal wetland. The total contents of QNs ranged from 0.33 to 21.60 ng/g dw (mean value of 4.51 ng/g dw), following the detection frequencies of QNs ranging from 19.23 to 94.23%. The highest content of QNs occurred around an aquaculture pond dominated by flumequine. The total organic carbon contents of sediment were positively correlated with sarafloxacin and lomefloxacin (p < 0.05), indicating the enhanced absorption of these QNs onto sediments. Partial QNs, such as lomefloxacin, enrofloxacin, sarafloxacin and flumequine, presented the homology features originating from the emission of medical treatment and aquaculture. There was no potential risk of QNs to human beings but a potential risk to aquatic organisms (algae > plant > invertebrate). Totally, the management and protection of Yancheng coastal wetland should be of concern with aquaculture as the important industry. [ABSTRACT FROM AUTHOR]

Coastal wetlands are important areas with valuable natural resources and diverse biodiversity. Due to the influence of both natural factors and human activities, the landscape of coastal wetlands undergoes significant changes. It is crucial to systematically monitor and analyze the dynamic changes in coastal wetland cover over a long-term time series. In this paper, a long-term time series coastal wetland remote sensing classification process was proposed, which integrated feature selection and sample migration. Utilizing Google Earth Engine (GEE) and Landsat TM/ETM/OLI remote sensing image data, the selected feature set is combined with the sample migration method to generate the training sample set for each target year. The Simple Non-Iterative Clustering-Random Forest (SNIC-RF) model was ultimately employed to accurately map wetland classes in the Liaohe Estuary from 1985 to 2023 and quantitatively evaluate the spatio-temporal pattern change characteristics of wetlands in the study area. The findings indicate that: (1) After feature selection, the accuracy of the model reached 0.88, and the separation of the selected feature set was good. (2) After sample migration, the overall accuracy of sample classification in the target year ranged from 87 to 94%, along with Kappa coefficients of 0.84 to 0.92, thereby ensuring the validity of classification sample migration. (3) SNIC-RF classification results showed better performance of wetland landscape. Compared with RF classification, the overall classification accuracy was increased by 0.69-5.82%, and the Kappa coefficient was increased by 0.0087-0.0751. (4) From 1985 to 2023, there has been a predominant trend of natural wetlands being converted into artificial wetlands. In recent years, this transition has occurred more gently. Finally, this study offers valuable insights into understanding changes and trends in the surface ecological environment of the Liaohe Estuary. The research method can be extended to other types of wetland classification and the comprehensive application of coastal wetland in hydrology, ecology, meteorology, soil, and environment can be further explored on the basis of this research, laying strong groundwork for shaping policies on ecological protection and restoration. [ABSTRACT FROM AUTHOR]

Over-summering of shorebirds refers to the phenomenon where certain species of shorebirds, primarily migratory, remain on their non-breeding grounds during the summer months for one or more years instead of migrating to their breeding grounds. The present study investigates the presence and abundance of over-summering shorebird species at four distinct sites covering 24 scanning points along the southeastern coasts of Tamil Nadu for 2017-2023. A total of 13 species were observed over-summering, with Lesser Sand Plover being the most dominant species, followed by Greater Sand Plover. Notably, 10 species were found across all four sites, while three species--Black-tailed Godwit, Bar-tailed Godwit, and Common Sandpiper--were exclusive to Dhanushkodi Lagoon, observed only during 2023. The study examined the year-wise abundance of these species, revealing a decline in over-summering shorebirds across all study sites. The Eurasian Curlew, Curlew Sandpiper, Bar-tailed & Black-tailed Godwits are the 'Near Threatened' species observed during the study. Furthermore, the research highlighted variations in Shannon species diversity index (H) location-wise and year-wise - Manoli Island (H = 2.25) in 2023; Dhanushkodi Lagoon (H = 1.8) in 2023; Valinokkam Lagoon (H = 1.63), and Pillaimadam Lagoon (H = 2.08) in 2017. Key findings are that among the study sites, in Pillaimadam Lagoon all 10 species' abundance declined; in Valinokkam Lagoon, Greater Sand Plover and Little Stint marginally increased, and eight species declined; Common Redshank and Ruddy Turnstone marginally increased in Manoli Island, while other eight species declined; Grey Plover population increased in Dhanushkodi Lagoon along with a marginal decrease in Common Redshank and Ruddy Turnstone as other species declined, over the years of study. [ABSTRACT FROM AUTHOR]

Peaty sediments in coastal wetlands play an important role in the sequestration of atmospheric carbon dioxide and its belowground storage. Sediment cores are used to quantify organic matter (OM) density, estimated by multiplying the bulk density of a core segment by its OM fraction. This method can be imprecise, as repeated samples often differ widely. Recent studies have shown that sediment bulk density and OM fraction are not independent but tightly related by a function called the ideal-mixing model. Thus, the bulk density of the sediment can be directly estimated from its OM fraction. Statistical theory and simulations demonstrate that the high variance in the product estimation of OM density is the result of error propagation in the product of two functionally related variables with independent errors. Estimating OM density in wetland sediments using the ideal-mixing model is more precise than the traditionally used product estimate, especially in highly organic sediments. [ABSTRACT FROM AUTHOR]

Suspended particulate matter (SPM) concentrations and associated estuarine high turbidity zones (HTZ) play crucial role in maintaining delta land building, coastal wetlands and marine ecosystems. In the background of new watersediment delivery regime and major geomorphological transition in delta, the long-term change characteristics and driving mechanisms of SPM and HTZ in the Yellow River Estuary (YRE) are not clarified. In this study, it was found that the existing SPM models could not be adapted to the extremely turbid YRE, for which a novel SPM retrieval algorithm and HTZ extraction method were developed. Spatiotemporal dynamics of SPM and HTZ in YRE from 1984 to 2023 were investigated using 798 Landsat TM/ETM+/OLI imageries. Results indicated that our proposed SPM algorithm outperformed all the previous models of YRE (R2 > 0.95, relative percentage difference (RPD)< 22%), and high accuracies were achieved for both satellite-derived SPM (RPD = 33.01%) and HTZ (overall accuracy = 94%). Over the last four decades, both SPM concentration and HTZ distribution area in YRE had demonstrated an increasing and then decreasing trend, reaching a peak around 1996. HTZ experienced four morphological transformations involving the circular shape surrounding coast (1984-1993), the enlarged southeasterly ovoid shape (1994-2007), the circle-like shape (2007-2017) and the thin northeasterly ovoid shape (2018-2023). Riverine sediment load and strong-wind frequency controlled 67% of interannual SPM variability in the study area, and the former contributed more. Moreover, combination of weakening ocean dynamics and coastal erosion, coarsening of sediments, and coastal defense structures led to an exponential decline of SPM concentrations in northern subregion. High sediment discharge and rapid accretion of estuarine spit in 1984-1996 resulted in increased SPM concentrations in southern subregion and a quick expansion of HTZ into Laizhou Bay. With the geomorphological evolution of new and old estuaries, the high velocity zone and strong bottom shear stress zone were consequently adjusted, which explained the interannual variability of SPM and HTZ in the region. This study will contribute to understanding of the long-term evolutionary patterns of the coupled system consisting of runoff-tidal dynamics, sediment transport and geomorphological development in the estuary. [ABSTRACT FROM AUTHOR]

Birds are sensitive to environmental changes and can drive range shifts rapidly due to their high mobility. Though previous studies have examined the associations between species traits and range shifts, whether species traits could still explain heterogeneity in shift directions remains poorly explored. Here, we compiled new bird records of China from 2000 to 2019 and analyzed species traits associated with apparent shift directions. We collected 350 provincial-level new records of birds belonging to 67 families of 22 orders. Of these, 32 are threatened, with 3 critically endangered, 11 endangered, and 18 vulnerable. Provinces in western China (i.e., Yunnan and Xizang) had relatively higher species richness of new recorded birds; this pattern was also reflected in the phylogenetic diversity we observed. In addition, provinces in northern China (i.e., Tianjin, Shandong, and Beijing) had relatively higher richness-controlled phylogenetic diversity. Phylogenetic overdispersion of new recorded bird communities was observed in 61.29% of provinces (19 of 31). The main shift directions indicated by new bird records were northward (with nearly 50% of birds moving NW, N and NE). Migration, hand-wing index (HWI), body mass, and range size are the four key factors that most significantly influence the shift directions in bird species, suggesting that bird movement toward newly suitable areas varies with species-specific traits. Together, these results demonstrate the importance of considering species ecological traits when predicting shift directions of birds. [ABSTRACT FROM AUTHOR]

Quantifying the vegetation aboveground biomass (AGB) is crucial for evaluating environment quality and estimating blue carbon in coastal wetlands. In this study, a UAV-LiDAR was first employed to quantify the canopy height model (CHM) of coastal Phragmites australis (common reed). Statistical correlations were explored between two multispectral remote sensing data (Sentinel-2 and JL-1) and reed biophysical parameters (CHM, density, and AGB) estimated from UAV-LiDAR data. Consequently, the reed AGB was separately estimated and mapped with UAV-LiDAR, Sentinel-2, and JL-1 data through the allometric equations (AEs). Results show that UAV-LiDAR-derived CHM at pixel size of 4 m agrees well with the observed stem height (R2 = 0.69). Reed height positively correlates with the basal diameter and negatively correlates with plant density. The optimal AGB inversion model was derived from Sentinel-2 data and JL-1 data with R2 = 0.58, RMSE = 216.86 g/m2 and R2 = 0.50, RMSE = 244.96 g/m2, respectively. This study illustrated that the synergy of UAV-LiDAR data and multispectral remote sensing images has great potential in coastal reed monitoring. [ABSTRACT FROM AUTHOR]

Soil microorganisms play a crucial role in the plant invasion process, acting as both drivers of and responders to plant invasion. However, the effects of plant invasion on the complexity and stability of co-occurrence networks of soil microbial communities remain unclear. Here, we investigated how the invasion of Spartina alterniflora affected the diversity, composition, and co-occurrence networks of soil bacterial and fungal communities in the Yellow River Delta, China. Compared to the native plant (Suaeda salsa), S. alterniflora invasion decreased the α-diversity of soil bacterial communities but did not affect that of fungal communities. The β-diversity of soil bacterial and fungal communities under S. salsa and S. alterniflora habitats also differed dramatically. S. alterniflora invasion increased the relative abundance of the copiotrophic phylum Bacteroidota, whereas decreased the relative abundances of the oligotrophic phyla Acidobacteriota and Gemmatimonadota. Additionally, the relative abundance of Chytridiomycota, known for its role in degrading recalcitrant organic matter, increased substantially within the soil fungal community. Functional predictions revealed that S. alterniflora invasion increased the relative abundance of certain soil bacteria involved in carbon and nitrogen cycling, including aerobic chemoheterotrophy, nitrate reduction, and nitrate respiration. More importantly, S. alterniflora invasion reduced the complexity and stability of both soil bacterial and fungal community networks. The shifts in soil microbial community structure and diversity were mainly induced by soil available nutrients and soil salinity. Overall, our study highlights the profound impacts of S. alterniflora invasion on soil microbial communities, which could further indicate the modification of ecosystem functioning by invasive species. [ABSTRACT FROM AUTHOR]

The carbon sink of cultivation shellfish in coastal wetlands is characterized as both highly ecological and economic value, thus making great contributions to achieving carbon neutrality. In this study, the main species of cultured shellfish (Ruditapes philippinarum, Meretrix meretrix, Sinonovacula constricta, Scapharca suberenata, and Grassostrea gigas) were selected as the research objects in the coastal wetland of the Yalu River Estuary to measure shellfish yields and carbon contents. Combined with the data from the cultured shellfish of fishery statistics of Donggang city, Dandong, Liaoning Province, China, the carbon sequestration capacity was calculated, and the carbon sink values of cultured shellfish also evaluated on the base of the diverse shellfish carbon sequestration ratios. The carbon sink conversion ratio of cultivation shellfish decreased in the following order: S. suberenata, R. philippinarum, G. gigas, S. constricta, and M. meretrix. The total carbon sequestration of cultured shellfish in the Yalu River Estuary Coastal Wetland from 2015 to 2019 was approximately 110,500 tC. The yield and the carbon sequestration quantity of R. philippinarum accounted for 76.60~83.30% of the total yield and 79.07~85.41% of the total carbon sequestration quantity. The value of the carbon sink was approximately 63,710,600 yuan. Among the species of cultured shellfish, R. philippinarum was the largest contributor to the carbon sink value. Based on Tapio's decoupling model, R. philippinarum has the most ideal state of decoupling between carbon sink and economic growth of cultured shellfish, followed by M. meretrix and S. suberenata. Our results illustrate that the development of coastal wetland shellfish aquaculture has a positive contribution to reducing carbon emissions and increasing carbon sinks. [ABSTRACT FROM AUTHOR]

Sea-level rise (SLR) is one of the most unequivocal consequences of climate change, yet the implications for shorebirds and their coastal habitats are not well understood, especially outside of the north temperate zone. Here, we show that by the year 2050, SLR has the potential to cause significant habitat loss and reduce the quality of the remaining coastal wetlands in Northwest Mexico—one of the most important regions for Nearctic breeding migratory shorebirds. Specifically, we used species distribution modeling and a moderate SLR static inundation scenario to assess the effects of future SLR on coastal wetlands in Northwest Mexico and the potential distribution of Calidris canutus roselaari (Red Knot), a threatened long-distance migratory shorebird. Our results suggest that under a moderate SLR scenario, 55% of the current coastal wetland extent in northwest Mexico will be at risk of permanent submergence by 2050, and the high-quality habitat areas that remain will be 20% less suitable for C. c. roselaari. What is more, 8 out of the 10 wetlands currently supporting the largest numbers of C. c. roselaari are predicted to lose, on average, 17.8% of their Highly Suitable Habitat (HSH) areas, with 2 sites completely losing all of their HSH. In combination with increasing levels of coastal development and anthropogenic disturbance in Northwest Mexico, these predicted changes suggest that the potential future distribution of C. c. roselaari (and other shorebirds) will likely contract, exacerbating their ongoing population declines. Our results also make clear that SLR will likely have profound effects on ecosystems outside the north temperate zones, providing a clarion call to natural resource managers. Urgent action is required to begin securing sufficient space to accommodate the natural capacity of wetlands to migrate inland and implement local-scale solutions that strengthen the resilience of wetlands and human populations to SLR. [ABSTRACT FROM AUTHOR]

Coastal wetlands play an important role in the global water and biogeochemical cycles. Climate change makes it more difficult for these ecosystems to adapt to the fluctuation in sea levels and other environmental changes. Given the importance of eco-geomorphological processes for coastal wetland resilience, many eco-geomorphology models differing in complexity and numerical schemes have been developed in recent decades. However, their divergent estimates of the response of coastal wetlands to climate change indicate that substantial structural uncertainties exist in these models. To investigate the structural uncertainty of coastal wetland eco-geomorphology models, we developed a multi-algorithm model framework of eco-geomorphological processes, such as mineral accretion and organic matter accretion, within a single hydrodynamics model. The framework is designed to explore possible ways to represent coastal wetland eco-geomorphology in Earth system models and reduce the related uncertainties in global applications. We tested this model framework at three representative coastal wetland sites: two saltmarsh wetlands (Venice Lagoon and Plum Island Estuary) and a mangrove wetland (Hunter Estuary). Through the model-data comparison, we showed the importance of using a multi-algorithm ensemble approach for more robust predictions of the evolution of coastal wetlands. We also found that more observations of mineral and organic matter accretion at different elevations of coastal wetlands and evaluation of the coastal wetland models at different sites in diverse environments can help reduce the model uncertainty. [ABSTRACT FROM AUTHOR]

Coastal wetland ecosystems in the Gulf of Mexico provide a variety of services including high rates of carbon sequestration and storage, making their assessment and conservation essential. This study aimed to determine the spatial distribution of carbon stocks in protected and non-protected coastal wetland ecosystems along the Gulf of Mexico in Mexico. Aboveground carbon (AGC) and belowground carbon (BGC) stocks were quantified using predictive random forest models. The study analyzed carbon estimates in AGC and BGC across different coastal wetland ecosystems and assessed the carbon storage of protected areas (PAs) and non-protected areas (non-PAs) for carbon conservation. Field surveys provided biomass and soil carbon data for modeling training, incorporating environmental features such as canopy height, vegetation indices, and soil characteristics. The results reveal differences in carbon stocks quantities among various vegetation types, with mixed mangroves exhibiting the highest AGC stock (93.7 ± 8.4 Mg C ha−1) and herbaceous wetlands displaying the smallest range (3.9 ± 1.3 Mg C ha−1) across sites. Notably, cattail marshes showed the highest average BGC stocks (505.6 ± 86.8 Mg C ha−1), influenced by factors such as soil characteristics and land cover. Spatial distribution maps of AGC and BGC provided insights into areas of high and low carbon storage. Interestingly, non-PAs showed higher carbon stocks than certain PAs, emphasizing the importance of including both protected and non-protected areas in conservation efforts. These findings highlight the significance of carbon storage across coastal wetland ecosystems, and the need for comprehensive conservation strategies to preserve their valuable ecosystem services. [ABSTRACT FROM AUTHOR]

Simple Summary: Ecosystems store large amounts of carbon, contributing to the control of the gases that lead to climate change. At the same time, certain species provide beneficial materials for the production of fodder or organic fertilizers. This research measured the amount of carbon stored by, and the biomass provision potential of, a water lettuce (Pistia stratiotes) population in a disturbed and unprotected Peruvian coastal wetland ecosystem. The results indicated that this population stored 3942.57 tCO2 and that a potential 2132.41 tons of biomass could be obtained for fodder. This pioneering research in Peru measured these ecosystem services, demonstrating the potential of this population of floating aquatic plants to provide both services. One of the most fascinating wetlands on Peru's central coast is the Santa Rosa wetland (Chancay, Lima), an ecosystem threatened by anthropogenic activities. Some of these impacts have led to the uncontrolled growth of Pistia stratiotes, an invasive aquatic plant. This study sought to quantify the regulation and provisioning of ecosystem services provided by P. stratiotes using carbon storage and the provision of biomass as indicators. To this end, the biomasses of 50 plots measuring 0.0625 m2 were weighed and georeferenced and the percentages of dry biomass (%DB) and total organic carbon in the biomass (%C) were quantified. The biomass and its coordinates were entered into ArcGIS and a Kriging interpolation technique was applied to determine the total amount of biomass (B). It was found that P. stratiotes stored 3942.57 tCO2 and that 2132.41 tons of biomass could be obtained for fodder. The total carbon stored by this aquatic plant represented 28.46% of the total carbon sequestered in the wetland ecosystem by vascular plants, suggesting that its contribution to the carbon cycle is significant. This is the first study to estimate the biomass of a floating aquatic plant population in a coastal Peruvian wetland and is a pioneering study addressing the in situ carbon estimation of Peruvian floating aquatic plants. The results and methods proposed in this research will serve in the evaluation of the potential of ecosystem services among similar populations of floating aquatic species. In addition, the data presented can be used to establish plans for the management and use of this biomass in the production of soil fertilizers and cattle forage. [ABSTRACT FROM AUTHOR]

Mangrove ecosystems provide numerous ecological services and serve as vital habitats for a wide range of flora and fauna. Thus, accurate mapping and monitoring of relevant land covers in mangrove ecosystems are crucial for effective conservation and management efforts. In this study, we proposed a novel approach for mangrove ecosystem mapping using a Hybrid Selective Kernel-based Convolutional Neural Network (HSK-CNN) framework and multi-temporal Sentinel-2 imagery. A time series of the Normalized Difference Vegetation Index (NDVI) products derived from Sentinel-2 imagery was produced to capture the temporal behavior of land cover types in the dynamic ecosystem of the study area. The proposed algorithm integrated Selective Kernel-based feature extraction techniques to facilitate the effective learning and classification of multiple land cover types within the dynamic mangrove ecosystems. The model demonstrated a high Overall Accuracy (OA) of 94% in classifying eight land cover classes, including mangrove, tidal zone, water, mudflat, urban, and vegetation. The HSK-CNN demonstrated superior performance compared to other algorithms, including random forest (OA = 85%), XGBoost (OA = 87%), Three-Dimensional (3D)-DenseNet (OA = 90%), Two-Dimensional (2D)-CNN (OA = 91%), Multi-Layer Perceptron (MLP)-Mixer (OA = 92%), and Swin Transformer (OA = 93%). Additionally, it was observed that the structure of the network, such as the types of convolutional layers and patch sizes, affected the classification accuracy using the proposed model and, thus, the optimum scenarios and values of these parameters should be determined to obtain the highest possible classification accuracy. Overall, it was observed that the produced map could offer valuable insights into the distribution of different land cover types in the mangrove ecosystem, facilitating informed decision-making for conservation and sustainable management efforts. [ABSTRACT FROM AUTHOR]

Aboveground biomass (AGB) serves as a crucial indicator of the carbon sequestration capacity of coastal wetland ecosystems. Conducting extensive field surveys in coastal wetlands is both time-consuming and labor-intensive. Unmanned aerial vehicles (UAVs) and satellite remote sensing have been widely utilized to estimate regional AGB. However, the mixed pixel effects in satellite remote sensing hinder the precise estimation of AGB, while high-spatial resolution UAVs face challenges in estimating large-scale AGB. To fill this gap, this study proposed an integrated approach for estimating AGB using field sampling, a UAV, and Sentinel-2 satellite data. Firstly, based on multispectral data from the UAV, vegetation indices were computed and matched with field sampling data to develop the Field–UAV AGB estimation model, yielding AGB results at the UAV scale (1 m). Subsequently, these results were upscaled to the Sentinel-2 satellite scale (10 m). Vegetation indices from Sentinel-2 data were calculated and matched to establish the UAV–Satellite AGB model, enabling the estimation of AGB over large regional areas. Our findings revealed the AGB estimation model achieved an R2 value of 0.58 at the UAV scale and 0.74 at the satellite scale, significantly outperforming direct modeling from field data to satellite (R2 = −0.04). The AGB densities of the wetlands in Xieqian Bay, Meishan Bay, and Hangzhou Bay, Zhejiang Province, were 1440.27 g/m2, 1508.65 g/m2, and 1545.11 g/m2, respectively. The total AGB quantities were estimated to be 30,526.08 t, 34,219.97 t, and 296,382.91 t, respectively. This study underscores the potential of integrating UAV and satellite remote sensing for accurately assessing AGB in large coastal wetland regions, providing valuable support for the conservation and management of coastal wetland ecosystems. [ABSTRACT FROM AUTHOR]

Shrub encroachment in coastal wetlands leads to heterogeneous distribution of soil resources, which may affect soil particle size distribution (PSD). Fractal theory was widely used to quantify the characteristics of soil PSD. However, exploration on the spatial changes in PSD of deep soil layers due to shrub-encroached vegetation succession is limited. Multifractal theory and GIS spatial analysis tools were used to spatially quantify the changes in soil PSD at different soil layers (0–80 cm) in a coastal wetland landscape (100 × 120 m) encroached by a native shrub Tamarix chinensis in the Yellow River Delta (YRD), China. We also discussed the potential mechanisms of soil PSD changes contributed by shrub encroachment. The results showed that higher content of fine sand, medium sand and coarse sand, while lower content of silt and very fine sand in 0–10 cm were observed in T.chinensis patches than in single T. chinensis and bare land (p < 0.05). In 30–40 cm, however, T.chinensis patches have higher soil clay content (p < 0.05). The generalized dimensional spectrum and multifractal parameters indicated that soil PSD in shrub patch area exhibited greater width and higher heterogeneity. Multifractal method could explain the changes of soil PSD better than single fractal dimension (D), and the Capacity Dimension (D0) was the most effective one to quantify the soil PSD characteristics. The values of D0 showed a clear order of shrub patch > single shrub > bare land in each layer. In addition, the D0 suggested that influences of T.chinensis on soil PSD can remain 70 cm below the surface in our case. Considering the complex sedimentary process in the YRD, the processes of water and wind erosion mediated by shrub encroachment, the positive feedback based on plant preferences and the mixed effects of shrub and grass species might promote the redistribution of soil particle size. Encroachment in coastal wetland of the YRD caused changes in soil PSD, especially at the surface soil layer. Multifractal parameters could quantify subtle characteristics of soil PSD in shrub-encroached area. Our work indicates that shrub encroachment in coastal wetland plays a significant role in altering regional and even global soil environments.Highlights: The soil in Tamarix chinensis patches showed higher content of clay, fine sand, and medium sand than bare land as a result of shrub encroachment. Multifractal parameters, especially the capacity dimension (D0), were good indicators to reveal the characteristics of soil particle size distribution (PSD). The generalized dimensional spectrum indicated that soil PSD of T.chinensis patches have high heterogeneity. The impacts of shrub on soil PSD can extend up to 70 cm depth in this T.chinensis encroached area of the Yellow River Delta. [ABSTRACT FROM AUTHOR]

Wetland ecosystems have become one of the long-term solutions for mitigating global climate change due to their strong carbon sequestration potential. However, the key carbon cycle processes in wetland ecosystems still lack a systematic summary. In the context of wetland protection and restoration, there is still a lack of consensus on the technical pathways to realize carbon sink multiplication in wetland ecosystems. In this paper, the key processes of carbon cycle, such as photosynthetic carbon uptake, microbial carbon decomposition and carbon deposition and burial, are sorted out and summarized in four major wetland types, namely, swamp and peat wetlands, river and riparian wetlands, lake and lakeshore wetlands, and estuarine and coastal wetlands. Based on the key processes of carbon cycle, three technological pathways for carbon sink multiplication are proposed, including, vegetation carbon sequestration and sink enhancement technology, soil carbon emission reduction technology and carbon deposition and burial technology. The key technologies under each pathway are further refined. And the carbon sink effects of the carbon sink technologies in different wetland types are qualitatively described. Also, wetland protection and restoration methods in corresponding regions are given in the light of the regional characteristics of wetlands in China. This will provide a scientific basis for the strategy of doubling the carbon sinks of China's wetland ecosystems. [ABSTRACT FROM AUTHOR]

Background: Ecological restoration of coastal wetlands has become particularly urgent worldwide as wetland areas have declined dramatically over the past two decades. Aims: To understand the nitrogen allocation strategy of Scirpus mariqueter (S. mariqueter) and provide theory support for future wetland management and restoration. Methods: The study investigated the response mechanism of S. mariqueter to altitude spatial changes in Nanhui Dongtan from 2017 to 2019 using remote sensing imagery and field surveys. The ecological adaptability of S. mariqueter at different elevations (denoted as A, B, and C for elevations 2.40, 3.15, and 3.49 m, respectively) was analyzed through 15N stable isotope tracing technology. In July and September 2020, 15N‐enriched urea solution was uniformly sprayed onto the leaf surfaces of S. mariqueter at different sites. Plant samples were collected at the end of July and September, and the aboveground, belowground, seed, and rhizome biomass were measured, followed by 15N isotope tests. Results: (1) From 2017 to 2019, the biomass of S. mariqueter significantly increased in the elevation change of 0.44–0.48 m, with the maximum aboveground biomass increase of 488.70 g dm−2. The density also increased significantly in the elevation change of 0.13–0.43 m, peaking at 674.02 plants m−2; (2) during the growing period, the biomass of A, B, and C increased. The aboveground portion of the 15N allocation rate accounted for 74%–84%. The belowground portion of the 15N allocation rate positively correlated with elevation; (3) during the reproductive period, elevation positively correlated with the 15N distribution rate of seeds and corms, as well as the biomass allocation rate of seeds and aboveground portions. The 15N allocation rate of the corms was higher than that of seeds. Additionally, elevation exhibited a negative correlation with belowground biomass allocation rate. (4) Point A has the highest difference of above and belowground biomass proportion, and 15N isotope allocation. Area of point A is the critical area affecting vegetation expansion and should be paid more attention in the future work of coastal management and restoration. Conclusion: There is an adaption strategy of S. mariqueter that affects the plant‐soil interaction and the biogeomorphological development process along the elevation gradient. [ABSTRACT FROM AUTHOR]

Restorations of former cranberry farms ("bogs") aim to re-establish native wetland vegetation, promote cold water habitat, and attenuate nitrogen (N) delivery to coastal waters. It is unclear, though, how elements of restoration design such as microtopography, groundwater interception, and plant communities affect N removal via denitrification. In a recently restored riparian cranberry bog with created microtopography, we compared denitrification potential, nitrous oxide (N2O) yield of denitrification (ratio of N2O:N2O + N2 gases), in situ N2O fluxes, soil chemistry, and plant communities at the highest and lowest elevations within 20 plots and at four side-channel groundwater seeps. Denitrification potential was > 2 × greater at low elevations, which had plant communities distinct from high elevations, and was positively correlated with plant species richness (Spearman's rho = 0.43). Despite detecting high N2O yield (0.86 ± 0.16) from low elevation soils, we observed small N2O emissions in situ, suggesting minimal incomplete denitrification even in saturated depressions. Groundwater seeps had an order of magnitude higher denitrification potentials and 100–300 × greater soil NO3− concentrations than the typically saturated low elevation soils. Groundwater seeps also had high N2O yield (1.05 ± 0.15) and higher, but spatially variable, in situ N2O emissions. Our results indicate that N removal is concentrated where soils interact with NO3–rich groundwater, but other factors such as low soil carbon (C) also limit denitrification. Designing restoration features to increase groundwater residence time, particularly in low lying, species rich areas, may promote more N attenuation in restored cranberry bogs and other herbaceous riparian wetlands. [ABSTRACT FROM AUTHOR]