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Williams, H.F.L., 2024. Testing digital elevation model of difference (DoD) estimation of washover fan thickness, Matagorda Peninsula, Texas. Journal of Coastal Research, 40(5), 852–859. Charlotte (North Carolina), ISSN 0749-0208. Washover fans are a fundamental component of coastal sediment budgets. While fans can be relatively easily delineated on air photos to obtain fan area, measurement of fan thickness, which is required for volume estimation, is problematic. Field surveys can be conducted, but fieldwork can be labor-intensive, costly, and time-consuming and have access problems. This study used pre- and poststorm LIDAR digital elevation models (DEMs) to create a digital elevation model of difference (DoD), which was then used to estimate the mean thicknesses of 10 Hurricane Harvey washover fans on Matagorda Peninsula, Texas. The accuracy of the LIDAR-derived fan thicknesses was assessed by comparing the LIDAR results to fan mean thicknesses based on pits excavated into fans. Seven out of 10 LIDAR-based thicknesses underestimated pit-based thicknesses, suggesting the presence of systematic bias in the LIDAR-derived DEMs. Underestimation of fan thicknesses was in the range of 36% to 56%. The source of the suspected bias is uncertain; it is possible that compaction of marsh sediments by the washover fans lowered the fans and reduced their apparent thicknesses. It is concluded that pre- and post-storm LIDAR DEMs can be used to estimate washover fan thickness, but in areas of compactible substrates, such as coastal marshes, steps should be taken to identify, evaluate, and address potential bias in the DEM data. [ABSTRACT FROM AUTHOR]

This manuscript provides guidance concerning how to use the Total Operating Characteristic (TOC) when (1) analyzing change through time, (2) ranking a categorical independent variable, and (3) constraining the extent for a gaining category. The illustrative variable is the marsh land-cover category in the Plum Island Ecosystems of northeastern Massachusetts, USA. The data are an elevation map and maps showing the land categories of water, marsh, and upland in 1938, 1971, and 2013. There were losses and gains near the edge of the marsh between 1938 and 1972 and between 1972 and 2013. The TOC curves show that marsh gained most intensively at intermediate elevations during the first time interval and then had a weaker association with elevation during the second time interval. Marsh gains more intensively from water than from upland during both time intervals. The TOC curves also demonstrate that the marsh gains occurred where marsh was previously lost, a phenomenon called Alternation. Furthermore, eliminating far distances and extreme elevations from the spatial extent decreased the area under the curve (AUC) for distance and increased the AUC for elevation. We invite scientists to use the TOC because the TOC is easier to interpret and shows more information than the Relative Operative Characteristic. [ABSTRACT FROM AUTHOR]

A network of 15 Surface Elevation Tables (SETs) at North Inlet estuary, South Carolina, has been monitored on annual or monthly time scales beginning from 1990 to 1996 and continuing through 2022. Of 73 time series in control plots, 12 had elevation gains equal to or exceeding the local rate of sea-level rise (SLR, 0.34 cm/year). Rising marsh elevation in North Inlet is dominated by organic production and, we hypothesize, is proportional to net ecosystem production. The rate of elevation gain was 0.47 cm/year in plots experimentally fertilized for 10 years with N&P compared to nearby control plots that have gained 0.1 cm/year in 26 years. The excess gains and losses of elevation in fertilized plots were accounted for by changes in belowground biomass and turnover. This is supported by bioassay experiments in marsh organs where at age 2 the belowground biomass of fertilized S. alterniflora plants was increasing by 1,994 g m−2 year−1, which added a growth premium of 2.4 cm/year to elevation gain. This was contrasted with the net belowground growth of 746 g m−2 year−1 in controls, which can add 0.89 cm/year to elevation. Root biomass density was greater in the fertilized bioassay treatments than in controls, plateauing at about 1,374 g m−2 and 472 g m−2, respectively. Growth of belowground biomass was dominated by rhizomes, which grew to 3,648 g m−2 in the fertilized treatments after 3 years and 1,439 g m−2 in the control treatments after 5 years. Depositional wetlands are limited by an exogenous supply of mineral sediment, whereas marshes like North Inlet could be classified as autonomous because they depend on in situ organic production to maintain elevation. Autonomous wetlands are more vulnerable to SLR because their elevation gains are constrained ultimately by photosynthetic efficiency. [ABSTRACT FROM AUTHOR]

Tidal marshes build elevations by below- and aboveground organic and mineral soil processes. Marsh elevation and accretion data can be used to determine if marshes are keeping pace with sea-level rise. Using a network of 54 deep rod surface elevation tables with paired feldspar marker horizon plots, we tracked elevation and accretion trends across 16 marshes in California, USA. All sites had overall positive gains across years that included severe drought conditions and extreme rain events. Marsh elevation relative to tidal datum (z*) was the key predictor for elevation and accretion rates, with higher change rates at lower z* sites. Marsh sites are clustered into three regional groups (Northern California, San Francisco Bay area, and Southern California), primarily defined by maximum temperature and annual rainfall differences. Elevation, accretion, and shallow subsidence rates were not significantly different between clusters, but their explanatory variables did vary. High-temperature days were a key predictor for elevation, accretion, and shallow subsidence rates in the state-wide analysis and San Francisco Bay regional analysis. The largest elevation gains were observed in the San Francisco Bay-Delta and some of the smallest in Humboldt Bay, with Morro Bay having the lowest accretion rate overall. Central and Southern California marshes were keeping pace or out-pacing sea-level rise, while none of the Humboldt Bay marshes were keeping pace. Marsh surface elevation data can inform management intervention and be a leading indicator for sea-level rise vulnerability. Long-term monitoring across geomorphic settings can help inform management and anticipate marsh change. [ABSTRACT FROM AUTHOR]

Threats to coastal wetlands, including sea-level rise and subsidence, led the National Wildlife Refuge (NWR) System to protect over 500,000 hectares of coastal wetlands during the twentieth century, with approximately 20% occurring in the South Atlantic geography. This effort has involved systematic long-term monitoring of changes in marsh elevation using surface elevation tables and marker horizons at 20 sites across 19 NWRs in the southeastern coastal USA. From 2012 to 2021, the rates of change in surface elevation (−9.3 to 7.1 mm/year), accretion (−0.3 to 17.5 mm/year), and net vertical elevation change (−14.3 to 3.1 mm/year) were highly variable among monitoring sites and varied with coastal wetland type (oligohaline marsh, salt marsh, pocosin, or forested wetland), land surface elevation, and estuarine salinity and geomorphology (i.e., tidally influenced or embayed). Of 20 sites included in our study, only six were gaining elevation at a rate that was equal to or greater than the long-term rates of sea-level rise and therefore considered resilient. Only Waccamaw and Currituck NWRs, both located in oligohaline marshes, were gaining elevation at a rate that exceeded sea-level rise by 1 mm/year. These results support the mounting evidence that many coastal wetlands, particularly in the South Atlantic geography of the USA, will undergo ecological transformations in the next several decades. The NWR System and other coastal management entities will need to use strategic decision-making frameworks to identify management actions that can mitigate the loss of coastal wetlands to support the conservation of coastal wetland–dependent and obligate species. [ABSTRACT FROM AUTHOR]

Benthic invertebrates play vital roles in estuarine ecosystems, but like other taxa they have been excluded from former marshlands by diking and land use conversion. Dike removal is one way of restoring marsh, but the response of benthic invertebrates has been little studied. Also understudied is variation in benthic invertebrate communities across entire deltas, particularly in the Pacific Northwest of North America where deltas receive high flows and sediment loads for their size. Our goals were to evaluate invertebrate response to large-scale dike removal on the Nisqually River Delta in Puget Sound, Washington, U.S.A., characterize delta-wide invertebrate community variation, and relate invertebrate response and spatial variation to environmental conditions. We sampled invertebrates annually from one year before to three years after dike removal in restoring marsh, previously restored marsh, undisturbed reference marsh, and adjacent tidal flats. Marine taxa immediately colonized the area recently restored to tidal inundation and population size grew exponentially thereafter for several of them. Community composition and diversity recovered completely, and density and biomass were approaching recovery three years later. Invertebrate communities converged between restoring and pre-existing marsh (previously restored and reference), suggesting an influence of reestablished connectivity. Just offshore from the dike line, invertebrates declined one year after dike removal but then rebounded indicating resilience to short-term disturbance. Dike removal effects were not detected farther offshore. Near the offshore edge of the delta, invertebrate biomass and body size were greater than elsewhere and a diverse assemblage of crustaceans, polychaetes, and bivalves was present. Farther inshore, tidal flats were dominated by a few species of small-bodied polychaetes and had higher density but lower biomass and diversity. Facultative detritivores, which can also filter feed, were the dominant feeding guild everywhere on the tidal flats. Density, biomass, diversity, and community composition on the marsh were more similar to the inner than outer tidal flats. Environmental variables most associated with invertebrate community variation were elevation, salinity, and sediment grain size and organic content. Our results are relevant to assessing performance and setting expectations for future restorations and have broad implications for the role of benthic invertebrates in estuarine ecosystems. [ABSTRACT FROM AUTHOR]

Shallow coastal systems act as nursery habitat for many species of fish and macroinvertebrates. Juveniles of these species may show selective use of certain habitat types over others, but the degree of such selectivity is not well studied for many species. Analysis of habitat selectivity is often hindered by inherently different gear types used in the habitats examined, which may not allow for direct comparison between the habitats. Here, we carry out nekton catches in the fringing marsh, using fyke nets, and in the adjacent seagrass habitat, using trawls, in the northern Gulf of Mexico to assess the relative use of the two habitats by the juveniles of six widespread important species. To resolve issues of gear comparability between fyke nets and trawls, we develop a habitat use index (HUI S) . The results reveal a consistent trend where, in relation to pinfish, speckled sea trout shows slightly higher (from 8.4 to 66.9 times); American silver perch and brown shrimp show moderately higher (from 2.3 to 369.4 times); and blue crab and white shrimp show greatly higher (from 90.6 to 2366.4 times) use of marsh over seagrass habitat. Thus, while similar in direction, differences in the use of marsh over seagrass habitat in relation to pinfish were more pronounced in some sites. We propose an index that can resolve issues of gear comparability and improve our understanding of coastal habitat selectivity by fish and macroinvertebrates. [ABSTRACT FROM AUTHOR]

We report a simple method for adjusting the weight input of the Marsh target-controlled infusion (TCI) model such that the resulting infusion regime closely mimics the behaviour of the Eleveld model, thereby making the Marsh model more precise for patients at the extremes of age and body mass index. To assess the performance of our method, we simulated 2768 subjects with diverse combinations of age, weight, height and sex undergoing a hypothetical four-hour propofol TCI using both the Marsh model with our weight adjustment and the Eleveld model. The weight adjusted Marsh model produced infusion regimes and corresponding effect site concentrations closely mimicking that of the Eleveld model at all time points, with median and maximum absolute performance errors less than 8.1% and 20.3%, respectively, across the entire cohort. Our weight adjustment method is a simple and robust way of improving the precision of the Marsh model in patients at extremes of age and body mass index, until general purpose TCI models for propofol, such as the Eleveld model, become more widely available in commercial infusion pumps. [ABSTRACT FROM AUTHOR]

This investigation evaluated two fundamental assumptions of wetland inundation models designed to emulate landscape evolution and resiliency under conditions of sea level rise: that they can (1) migrate landward at the same rate as the transgressing shoreline and (2) immediately replace the plant community into which they are onlapping. Rates of wetland (e.g., marsh, mangrove) migration were culled from 11 study areas located in five regions of focus: Delaware Bay, Chesapeake Bay, Pamlico Sound, South Florida, and Northwest Florida. The average rate of marsh migration (n = 14) was 3.7 m yr−1. The average rate of South Florida mangrove migration (n = 4) was 38.0 m yr−1. The average rate of upland forest retreat (n = 4) was 3.4 m yr−1. Theoretical rates of shoreline transgression were calculated using site-specific landscape slope and scenario-based NOAA sea level rise elevations in 2050. Rates of shoreline transgression over the marsh landscape averaged 94 m yr−1. The average rate of shoreline transgression in the mangrove-dominated areas of South Florida was 153.2 m yr−1. The calculated rates of shoreline transgression were much faster than the observed horizontal marsh migration, and by 2050, the offset or gap between them averaged 2700 m and ranged between 292 and 5531 m. In South Florida, the gap average was 3516 m and ranged between 2766 m and 4563 m. At sites where both horizontal marsh migration and forest retreat rates were available, the distance or gap between them in 2050 averaged 47 m. Therefore, the results of this study are inconsistent with the two fundamental assumptions of many wetland inundation models and suggest that they may overestimate their resilience under conditions of 21st century accelerating sea level rise. [ABSTRACT FROM AUTHOR]

"Blue carbon", apart from marine humus, includes the carbon (C) stock of coastal ecosystems such as mangroves, saltmarshes, and seagrass meadows, which have been overlooked until recently. Information about the role of coastal wetlands in C sequestration and providing other ecosystem services is still insufficient. In the present study, we assessed the C reserves of soils and vegetation biomass in two complex coastal landscapes (tombolos) located on the coasts of the White and Baltic seas. The soil and plant C stocks were slightly higher at the plot on the Baltic Sea (93.4 ± 46.7 Mg C·ha−1 and 5.22 ± 2.51 Mg C·ha−1, respectively) than at the plot on the White Sea (71.4 ± 38.2 Mg C·ha−1 and 3.95 ± 2.42 Mg C·ha−1, respectively). We attributed the higher values of the C reserved to a warmer climate and less saline water at the plot on the Baltic Sea. Both soil and plant C showed high heterogeneity due to geomorphological complexity and differences in vegetative communities. The Phragmites australis community showed the highest plant biomass and, in some places, high soil C reserves. Allochthonous C contributed to the soil C stock at the site on the White Sea. Though P. australis sequestered more C than other communities, its effect on ecosystem services was mostly negative because the invasion of reeds reduced the biological diversity of the marshes. [ABSTRACT FROM AUTHOR]

Nitrogen and phosphorus concentrations were quantified in interstitial water, soil, and the roots of Cladium jamaicense Crantz from four herbaceous wetlands in southeast Mexico, locally known as sabanas, which are established in the karstic valley of the Holbox fracture system (northern Quintana Roo). We used the physicochemical and hydrogeochemical properties of the water to identify the existence of any relationships between nutrient (nitrogen and phosphorus) concentration and stock, and the hydrogeochemistry of each wetland. The wetlands have different classifications: H1 and H2 are palustrine, H3 is lacustrine, and H4 is estuarine. We found greater total phosphorus mass (mg kg−1) in the roots compared to the soil, which was particularly large in the wetland located at the south end of the western fracture. In general, phosphorus and nitrogen had a trend in the interstitial water and soil in which concentration and mass were higher H1 > H3 > H4, different from H2; these trends were not observed in the soil or roots. The N and P concentrations in the soil and roots were different among the wetlands, with the lowest measured at the site with brackish influence. The results presented in this research allow us to compare the nitrogen and phosphorus that can be stored in tropical karst wetlands and relate them to hydrogeochemistry. [ABSTRACT FROM AUTHOR]

Benthic invertebrates play vital roles in estuarine ecosystems, but like other taxa they have been excluded from former marshlands by diking and land use conversion. Dike removal is one way of restoring marsh, but the response of benthic invertebrates has been little studied. Also understudied is variation in benthic invertebrate communities across entire deltas, particularly in the Pacific Northwest of North America where deltas receive high flows and sediment loads for their size. Our goals were to evaluate invertebrate response to large-scale dike removal on the Nisqually River Delta in Puget Sound, Washington, U.S.A., characterize delta-wide invertebrate community variation, and relate invertebrate response and spatial variation to environmental conditions. We sampled invertebrates annually from one year before to three years after dike removal in restoring marsh, previously restored marsh, undisturbed reference marsh, and adjacent tidal flats. Marine taxa immediately colonized the area recently restored to tidal inundation and population size grew exponentially thereafter for several of them. Community composition and diversity recovered completely, and density and biomass were approaching recovery three years later. Invertebrate communities converged between restoring and pre-existing marsh (previously restored and reference), suggesting an influence of reestablished connectivity. Just offshore from the dike line, invertebrates declined one year after dike removal but then rebounded indicating resilience to short-term disturbance. Dike removal effects were not detected farther offshore. Near the offshore edge of the delta, invertebrate biomass and body size were greater than elsewhere and a diverse assemblage of crustaceans, polychaetes, and bivalves was present. Farther inshore, tidal flats were dominated by a few species of small-bodied polychaetes and had higher density but lower biomass and diversity. Facultative detritivores, which can also filter feed, were the dominant feeding guild everywhere on the tidal flats. Density, biomass, diversity, and community composition on the marsh were more similar to the inner than outer tidal flats. Environmental variables most associated with invertebrate community variation were elevation, salinity, and sediment grain size and organic content. Our results are relevant to assessing performance and setting expectations for future restorations and have broad implications for the role of benthic invertebrates in estuarine ecosystems.

This manuscript provides guidance concerning how to use the Total Operating Characteristic (TOC) when (1) analyzing change through time, (2) ranking a categorical independent variable, and (3) constraining the extent for a gaining category. The illustrative variable is the marsh land-cover category in the Plum Island Ecosystems of northeastern Massachusetts, USA. The data are an elevation map and maps showing the land categories of water, marsh, and upland in 1938, 1971, and 2013. There were losses and gains near the edge of the marsh between 1938 and 1972 and between 1972 and 2013. The TOC curves show that marsh gained most intensively at intermediate elevations during the first time interval and then had a weaker association with elevation during the second time interval. Marsh gains more intensively from water than from upland during both time intervals. The TOC curves also demonstrate that the marsh gains occurred where marsh was previously lost, a phenomenon called Alternation. Furthermore, eliminating far distances and extreme elevations from the spatial extent decreased the area under the curve (AUC) for distance and increased the AUC for elevation. We invite scientists to use the TOC because the TOC is easier to interpret and shows more information than the Relative Operative Characteristic.

Mangroves, tidal marshes and seagrasses have experienced extensive historical reduction in extent due to direct and indirect effects of anthropogenic land use change. Habitat loss has contributed carbon emissions and led to foregone opportunities for carbon sequestration, which are disproportionately large due to high ‘blue carbon’ stocks and sequestration rates in these coastal ecosystems. As such, there has been a rapid increase in interest in using coastal habitat restoration as a climate change mitigation tool. This review shows that restoration efforts are able to substantially increase blue carbon stocks, while also having a positive impact on various gaseous fluxes. However, blue carbon increases are spatially variable, due to biophysical factors such as climate and geomorphic setting. While there are potentially hundreds of thousands of hectares of land that may be biophysically suitable for restoration, these activities are still often conducted at small scales and with mixed success. Maximizing potential carbon gains through blue carbon restoration will require managers and coastal planners to overcome the myriad socioeconomic and governance constraints related to land tenure, legislation, target setting and cost, which often push restoration projects into locations that are biophysically unsuitable for plant colonization.

Wetland restoration has received increasing attention to compensate for the continuing loss of natural wetlands and revive biodiversity and associated ecological functions. The development of methods for assessing the effectiveness of restoration measures is important for wetland management. However, most studies assessing restoration success in freshwater ecosystems are based on taxonomic biodiversity; trait-based approaches remain limited, particularly in wetland ecosystems. Here, we assess the effectiveness of wetland restoration in the Sanjiang Plain, Northeast China, based on the trait composition and functional diversity of aquatic insect assemblages. We found that functional richness in restored wetlands was significantly higher than impacted wetlands but lower than natural wetlands. Compared to natural wetlands, functional beta diversity of impacted wetlands was higher. In terms of dissimilarity between wetland types, trait composition of aquatic insects in restored wetlands showed a higher similarity to natural wetlands compared to those in impacted wetlands. Trait compositions of aquatic insect assemblages in restored wetlands were more similar to impacted wetlands in May but showed a greater similarity to natural wetlands in October. Our study shows that restoration measures have facilitated the partial recovery of functional diversity and trait composition of aquatic insect assemblages in the Sanjiang Plain wetlands. Our study confirms the potential of using trait-based approach to assess the effectiveness of wetland restoration. Given that assessments based on taxonomic and trait data can provide complementary information, we recommend incorporating both taxonomic and functional metrics and considering seasonal dynamics of wetlands in post-restoration monitoring and assessment in wetlands.

Riverine floodplains serve as an important link between terrestrial and aquatic systems, as the rising and falling of water drive spatial food web subsidies that are critical to the functioning and stability of ecosystems. As these systems are increasingly impacted by hydrological alterations and climate change, it is important to understand how floodplain spatial food web subsidies may respond to changing environmental conditions.Here, we examine the interannual variation in the structure of a sunfish (Lepomis spp.) prey subsidy from freshwater marshes into the mangrove‐lined creeks of Rookery Branch in the Florida Coastal Everglades that occurs during seasonal dry downs. We evaluate how the structure of this subsidy relates to prior temperature and hydrological regimes based on a 16‐year electrofishing dataset. We also characterise the intra‐annual relationship between marsh water depths and sunfish migration patterns that underlie this subsidy.We found that interannual variation in the abundance and diversity of the sunfish prey subsidy was best explained by the minimum water temperature occurring within 90 days prior to peak abundance sampling periods, with lower minimum water temperatures associated with higher sunfish abundance and diversity. In contrast, interannual variations in the biomass of the sunfish prey subsidy were positively related to marsh flooding duration over 30 cm depth during the prior wet season. Intra‐annual models estimated peak sunfish abundance and biomass values in riverine habitats to occur during the transition between wet and dry periods when marsh depths are between 10 and 15 cm.Multivariate analysis of community abundance and biomass composition revealed that minimum water temperatures played an important role in structuring the prey subsidy, while the effect of flooding duration was weak. These results provide important insight into how floodplain prey subsidies may be altered under future climate and hydrological regimes and inform ecosystem‐based water management decisions. [ABSTRACT FROM AUTHOR]

Controlling non-native plant invasions that reduce the quality of preferred wetland habitats is a challenge for many wetland managers. Herbicides may be used to control invasions, but it may be difficult to find effective application methods depending on the terrain. Manned aircraft cover large patches, but aerial use is limited by high costs, weather conditions, and overspray concerns. Ground applications target smaller patches, but their effectiveness may be limited by accessibility, labor costs, and applicator health concerns. Considering these difficulties, unmanned aerial systems (UAS) have emerged as a viable alternative for more effectively treating plant invasions. We tested the use of a specialized UAS to control invasive perennial pepperweed (Lepidium latifolium) in Suisun Marsh in northern California, USA. This "spray drone" flew at an altitude of 2–3 m, a speed of 24 kmph, and applied herbicide with a swath width of 6 m. We applied herbicide with the spray drone to treat small patches before they expanded. To delineate invasive patch boundaries, we first flew a survey drone with a 4K resolution camera to detect emerging plants with color imagery and conduct an initial classification analysis. We subsequently visited areas with suspected invasive patches based on the classification, and observers manually confirmed the presence of the invasive species. We then flew the spray drone on transects to treat the patches and examined the results with post-treatment survey drone imagery and plots along ground transects. In total, we sprayed 14 ha of Lepidium across eight sites and found that 87% of the Lepidium was discernibly affected by our herbicide treatment. Furthermore, we measured the overspray, which was substantially less than that reported for other aerial application methods such as helicopter-spraying, and our estimated operational costs were lower. Our results indicated that applying remote-sensing imagery for the identification of invasive species patches and the use of a spray drone for treatment may be an effective means of controlling invasive plants with high precision at a reasonable cost. In the near future, a unified UAS system that both identifies invasive species and then treats them in a single pass should be a promising goal for early detection and rapid response in wetland management. [ABSTRACT FROM AUTHOR]

Barrier coastlines and their associated ecosystems are rapidly changing. Barrier islands/spits, marshes, bays, and coastal forests are all thought to be intricately coupled, yet an understanding of how morphologic change in one part of the system affects the system altogether remains limited. Here we explore how sediment exchange controls the migration of different ecosystem boundaries and ecosystem extent over time using a new coupled model framework that connects components of the entire barrier landscape, from the ocean shoreface to mainland forest. In our experiments, landward barrier migration is the primary cause of back‐barrier marsh loss, while periods of barrier stability can allow for recovery of back‐barrier marsh extent. Although sea‐level rise exerts a dominant control on the extent of most ecosystems, we unexpectedly find that, for undeveloped barriers, bay extent is largely insensitive to sea‐level rise because increased landward barrier migration (bay narrowing) offsets increased marsh edge erosion (bay widening). Plain Language Summary: Barrier coastlines consist of barrier islands or spits, salt marshes, bays, and mainland forest. To understand how the migration and change in size of one ecosystem influences the others, we develop a new computer model that simulates the exchange of sediment between all ecosystems. Using this model, we find that salt marshes adjacent to barriers are rapidly lost when the barrier migrates and its sediment is washed onto the marsh, but can potentially expand and recover when the barrier is not migrating. Additionally, we find that changing the rate of sea‐level rise in the model does not significantly change the size of the bay because the effects of sea‐level rise on barrier migration and marsh edge erosion offset each other. Our simulations suggest that these interactions among different ecosystems result in complex evolution of coastal barrier systems and can be a leading cause of change. Key Points: Cross‐landscape interactions are explored in new model framework connecting entire barrier system from shoreface to mainland forestSimulations suggest barrier migration leads to rapid back‐barrier marsh loss, while barrier stability enables back‐barrier marsh recoveryBay extent is insensitive to sea‐level rise rates because of offsetting responses from barrier migration and marsh‐edge erosion processes [ABSTRACT FROM AUTHOR]

Abstract Barrier coastlines and their associated ecosystems are rapidly changing. Barrier islands/spits, marshes, bays, and coastal forests are all thought to be intricately coupled, yet an understanding of how morphologic change in one part of the system affects the system altogether remains limited. Here we explore how sediment exchange controls the migration of different ecosystem boundaries and ecosystem extent over time using a new coupled model framework that connects components of the entire barrier landscape, from the ocean shoreface to mainland forest. In our experiments, landward barrier migration is the primary cause of back‐barrier marsh loss, while periods of barrier stability can allow for recovery of back‐barrier marsh extent. Although sea‐level rise exerts a dominant control on the extent of most ecosystems, we unexpectedly find that, for undeveloped barriers, bay extent is largely insensitive to sea‐level rise because increased landward barrier migration (bay narrowing) offsets increased marsh edge erosion (bay widening).

Mechanisms that control marsh edge erosion include wind‐generated waves, vegetation productivity, land use and land change, and geotechnical properties of sediments. However, existing models for predicting marsh edge evolution focus primarily on edge retreat rates as a function of wave energy while accounting for other controlling factors as empirical constants. This simplification arises from a lack of high‐frequency monitoring of marsh evolutions. In particular, marsh erosion is timescale dependent, and conducting field observations on short temporal and spatial scales could elucidate the progression of erosion, which may improve marsh erosion predictive models. This study developed and validated a near‐continuous camera and erosion pin monitoring system to document marsh edge erosion at a high frequency (i.e., daily) in Terrebonne Bay, Louisiana. This was supplemented with daily wave power to explore the relationships between daily erosion and wave power. Long‐term average erosion rates derived from satellite and aerial imagery from 1989 through 2019 compare similarly to rates derived from longer‐term site visits (i.e., monthly) at approximately 2.2 m/yr. High‐magnitude erosion events (>20 cm/day) are driven by a buildup in wave energy over a 7‐day time period coupled with a strong 1‐day wave event, indicating a gradual reduction in marsh edge resistance with continued wave attack. Long‐term erosion monitoring methods, including monthly field visits, provide results that align well with previously reported relationships between wave power and erosion. High‐frequency measurements, however, illustrate that the previously published trends smooth over the large‐magnitude short‐term erosion events, potentially obscuring the physical processes of marsh edge erosion. For example, satellite and aerial imagery provide a long period of record, but they may underestimate the average annual erosion rate in the region, the effect of which may become exasperated over the varying temporal scales considered in coastal planning efforts across the USA and worldwide. [ABSTRACT FROM AUTHOR]

Inner Mongolia has a large area of marsh wetland in China, and the marsh in this region is important for maintaining ecological balance. Understanding variations in vegetation phenology of marsh ecosystems and their responses to climatic change is crucial for vegetation conservation of marsh wetlands in Inner Mongolia. Using the climate and NDVI data during 2001–2020, we explored the spatiotemporal changes in the start (SOS), end (EOS), and length (LOS) of vegetation growing season and analyzed the effects of climate change on vegetation phenology in the Inner Mongolia marshes. Results showed that SOS significantly (p < 0.05) advanced by 0.50 days/year, EOS significantly delayed by 0.38 days/year, and thus LOS considerably increased by 0.88 days/year during 2001–2020 in marshes of Inner Mongolia. Warming temperatures in winter and spring could significantly (p < 0.05) advance the SOS, and increased summer and autumn temperatures could delay EOS in Inner Mongolia marshes. We found for the first time that daytime maximum temperature (Tmax) and night minimum temperature (Tmin) had asymmetric effects on marsh vegetation phenology. Increasing Tmax had a stronger advancing effect on SOS than increasing Tmin from December to April. The increase of Tmin in August could obviously delayed EOS, while increasing Tmax in August had no significant effect on EOS. This study highlights that the asymmetric influences of nighttime and daytime temperatures should be taken into account in simulating marsh vegetation phenology in temperate arid and semi-arid regions worldwide, particularly in the context of global asymmetric diurnal warming. [ABSTRACT FROM AUTHOR]

Wetland ecosystems play key roles in global biogeochemical cycling, but their spatial extent and connectivity is often not well known. Here, we detect the spatial coverage and type of wetlands at 10 m resolution across southern Nigeria (total area: 147,094 km2), thought to be one of the most wetland-rich areas of Africa. We use Sentinel-1 and Sentinel-2 imagery supported by 1500 control points for algorithm training and validation. We estimate that the swamps, marshes, mangroves, and shallow water wetlands of southern Nigeria cover 29,924 km2 with 2% uncertainty of 460 km2. We found larger mangrove and smaller marsh extent than suggested by earlier, coarser spatial resolution studies. Average continuous wetland patch areas were 120, 11, 55 and 13 km2 for mangrove, marsh, swamp, and shallow water respectively. Our final map with 10 m pixels captures small patches of wetland which may not have been observed in earlier mapping exercises, with 20% of wetland patches being < 1 km2; these were clustered around urban centres, suggesting anthropogenic wetland fragmentation. Our approach fills a knowledge gap between very local (< 400 km2) studies reliant on field studies and aerial photos, and low resolution (> 250 m pixel dimensions) global wetland datasets and provides data critical for both improving land-surface climate models and for wetland conservation. [ABSTRACT FROM AUTHOR]

The king rail (Rallus elegans) is a secretive marsh bird that is threatened or endangered in eight of nine states and provinces in the Laurentian Great Lakes (Great Lakes) region. Available survey data suggests that this species has undergone population declines across this region and these are believed to have been driven by habitat loss and degradation. An improved understanding of the amount and type of habitat king rails require during the breeding season at sites within the Great Lakes region would inform and improve progress toward conservation goals. During 2019–2021, we caught and radio‐tagged 14 king rails in northwestern Ohio and southeastern Michigan within impounded coastal wetlands of western Lake Erie. We used radio telemetry to identify breeding season (May–August) home‐range characteristics and third order habitat selection within home ranges (hereafter microhabitat). For the birds whose home range stabilized (N = 10), we found a mean home‐range size of 8.8 ha (±1.63 [SE]; range = 1.9 to 15.8). We generated a classification tree to determine which habitat characteristics were associated with king rail presence within home ranges in our study. We found that vegetative density within home ranges was particularly associated with king rail presence. Phragmites australis was also associated with king rail presence, despite its invasiveness and negative ecological impacts in the region, and could be selectively maintained to benefit king rails. Our results suggest that managers may be able to provide microhabitat for king rails by maintaining water depths of 6 to 17 cm and by promoting native, robust vegetation in the genera Carex and Juncus. Our findings could help inform wetland managers and conservation planners in the Great Lakes region, particularly in western Lake Erie coastal marshes, of patch sizes, water depths, plant communities, and vegetative structure preferred by king rails. [ABSTRACT FROM AUTHOR]

Abstract The constant deficiency of water modality will increase the incidence of complaint, predominantly for unguarded people in undeveloped republics, where practical doses and substitutes are not enthusiastically available. Many wetland-reliant on types in many percentages of the ecosphere are in degeneration; the location of kind dependent on domestic waters are of exact uneasiness. The chief deficiency and impairment of rivers, branch, swamplands, and other interior wetlands have been occupant’s expansion and increasing financial development. The key deficiency and impairment include infrastructure development, land alteration, water removal, pollution, and the plan of offensive eccentric categories. Agronomical governments and approaches have applied a widespread diversity of characteristically conflicting properties on exclusive and coastal wetlands globally. The foremost the impairment and deficiency of wetlands, including seawater swamplands have been revision to other earthly practices. The most important changes were the development of anthropological populations in the coastal areas and the increase in economic activity. The destruction and dissolution of wetlands, an important route of travel, has endangered many species and injured others. Global climate change is estimated to increase the damage and deprivation of many wetlands, as well as the damage or degradation of their species, and harm the anthropological inhabitants who depend on the facility. Many wetlands change as a result of estimated sea level rise, increased storm surges and storm surges, variability in storm surge concentration and frequency, and fluctuations in waterway flow and sediment flow. The effects of global climate change often amplify the effects of wetland withdrawal. It is well known why many types of wetlands, such as lakes and wetlands, are relocated, transformed, or looted, but the benefits of their conservation are often greater than the benefits associated with their alteration. It will be bigger. In wetland conservation, indigenous peoples have often been excluded from the decision-making process. Decisions at many stages ignore the relationship between wetland conditions and the establishment of wetland facilities, and the resulting benefits to the individual. Many of the amenities supported by wetlands are unfunded and are accumulated in civilizations on a national and global scale. The benefits of transforming wetlands include those that stimulate wetland drainage for agriculture and those that stimulate important wetlands through intensive organizations that include advances in municipalities, manufacturing and recreational industries. It is repeatedly exaggerated by money. With the results in mind, high-level potential hazards and zones with different hazard levels and management approaches have been proposed for this wetland.

Abstract Background and Aims The immunohistochemical application of CD3 (T lymphocytes) and CD20 (B lymphocytes) markers in duodenal biopsy can facilitate the detection of the number and distribution of intraepithelial lymphocytes along the villi, which is regarded as a key factor for accurate diagnosis of celiac disease. This study aims at finding a relationship between CD3 and CD20 immunohistochemical and histopathological alterations of celiac disease, and at investigating whether the application of those immunohistochemical stainings would improve the detection of lymphocytosis within the epithelium and add advantages to celiac disease diagnosis. Methods Biopsies were obtained from 100 individuals and stained with hematoxylin and eosin (H&E). They were then evaluated according to the Marsh classification. After that, staining for CD3 and CD20 was individually done and assessed. Results The overall mean intraepithelial lymphocyte count per 100 enterocytes for H&E was 23.1 (95% confidence interval [CI] = 19.52–26.68), and for immunohistochemistry by CD3 and CD20 was 27.84 (95% CI = 24.31–31.38). The difference was highly significant, P = 0.001. The expression of CD3 immunohistochemically was as follows: Less‐than‐half staining pattern was reported in 16% cases, and half staining pattern was seen in 26%, while most cases 58% had more than half staining pattern. This discovery was consistent with the histological classification of March III among most cases. The expression of CD20 immunohistochemically was as follows: mild crypt involvement was observed in 16% of cases, while moderate crypt involvement and intense crypt involvement were seen in 43% and 41% of cases, respectively.

We have studied soils and the plant cover of tombolos, which are isthmuses between the mainland and small islands on the coasts of the White and Baltic seas. Tombolos are characterized by complicated dynamics of sedimentation, which results in a strong heterogeneity of soils and associated plant cover. Typical gley and surface-gley marsh soils are formed on the Kolezhma plot on the White Sea coast. The vegetation corresponds to marsh meadows of the lower and middle levels and depends on salinity, acidity, and soil texture. Soils on the Gakkovo plot on the Baltic Sea coast are characterized by greater uniformity and, in general, a sandy texture. As compared to the White Sea, the effect of the Baltic Sea on the soil and plant cover is significantly smaller due to its slighter tidal dynamics. [ABSTRACT FROM AUTHOR]

Sanjiang Plain is the largest marsh distribution area of China, and marshes in this region significantly affect regional carbon cycle and biodiversity protection. The vegetation phenology of marsh significantly affects the energy exchange and carbon cycle in that region. Under the influence of global climatic change, identifying the changes in phenology and their responses to climatic variation in marshes of Sanjiang Plain is essential for predicting the carbon stocks of marsh ecosystem in that region. Using climate and NDVI data, this paper analyzed the spatiotemporal variations in the start (SOS), end (EOS), and length (LOS) of vegetation growing season and explored the impacts of climatic variation on vegetation phenology in marshes of Sanjiang Plain. Results showed that the SOS advanced by 0.30 days/a, and EOS delayed by 0.23 days/a, causing LOS to increase significantly (p <.05) by 0.53 days/a over marshes of Sanjiang Plain. Spatially, the large SOS advance and EOS delay resulted in an obvious increasing trend for LOS in northern Sanjiang Plain. The rise of spring and winter temperatures advanced the SOS and increased the LOS, and the rise in temperature in autumn delayed the EOS in marshes of Sanjiang Plain. Our findings highlight the necessity of considering seasonal climatic conditions in simulating marsh vegetation phenology and indicate that the different influences of climatic variation on marsh vegetation phenology in different regions should be fully considered to assess the marsh ecosystem response to climatic change in Sanjiang Plain. [ABSTRACT FROM AUTHOR]

Net primary productivity (NPP) is a vital ecological index that reflects the ecological function and carbon sequestration of marsh ecosystem. Inner Mongolia has a large area of marshes, which play a crucial role in the East Asian carbon cycle. Under the influence of climate change, the NPP of Inner Mongolian marsh has changed significantly in the past few decades, but the spatiotemporal variation in marsh vegetation NPP and how climate change affects marsh NPP remain unclear. This study explores, for the first time, the spatiotemporal variation of marsh NPP and its response to climatic change in Inner Mongolia based on the MODIS-NPP and climate datasets. We find that the long-term average annual NPP of marsh is 339.85 g⋅C/m2 and the marsh NPP shows a significantly increasing trend (4.44 g⋅C/m2/a; p < 0.01) over Inner Mongolia during 2000–2020. Spatially, the most prominent increase trend of NPP is mainly distributed in the northeast of the region (Greater Khingan Mountains). The partial correlation results show that increasing autumn and summer precipitation can increase the NPP of marsh vegetation over Inner Mongolia. Regarding the temperature effects, we observe a strong asymmetric effect of maximum (Tmax) and minimum (Tmin) temperature on annual NPP. A high spring Tmax can markedly increase marsh NPP in Inner Mongolia, whereas a high Tmin can significantly reduce it. In contrast to spring temperature effects on NPP, a high summer Tmax can decrease NPP, whereas a high Tmin can increase it. Our results suggest different effects of seasonal climate conditions on marsh vegetation productivity and highlight the influences of day-time and night-time temperatures. This should be considered in simulating and predicting marsh carbon sequestration in global arid and semi-arid regions.

IntroductionCoastal estuarine wetlands provide important habitats for a variety of endemic flora and fauna but are particularly vulnerable to biological invasions. Regular monitoring of changes in these vulnerable wetlands has become increasingly important for effective management, especially considering threats from climate change effects and human disturbance. Historical analyzes of plant invasions may guide targeted management strategies to eradicate harmful species. Estimating the distribution of invasive species has never been more accessible with the improved availability of high-resolution data and innovations in remote sensing, estimating the distribution of invasive species has never been more accessible.MethodsWe assessed the spread of non-native Phragmites australis subsp. australis in Suisun Marsh on the upper San Francisco Estuary, one of the largest brackish coastal wetlands in North America. Suisun Marsh consists of managed and tidal wetlands, and efforts have been made to control invasive P. australis on the managed wetlands to support habitat values for wildlife. We used remote-sensing analyzes of publicly available, biennial color-infrared images taken by the National Agriculture Imagery Program (NAIP) to map the expansion of invasive P. australis across two decades. We generated random forest classifications of representative images to map the distribution of P. australis, then calculated a variety of metrics describing the rate and spatial extent of the P. australis spread. Additionally, we ran generalized linear models to examine factors related to the growth of P. australis.ResultsOur classifications yielded accuracies of over 90% and showed a 234% (1,084 ha) increase in P. australis between 2003 and 2018. The expansion rate of P. australis patches averaged 1.32 m/year (±0.53 SD) which is higher than most reported in the literature. We found that P. australis expansion in managed areas within levees was significantly correlated with invasion in tidal areas outside the levees on the same parcel and also related to its spread on adjacent parcels.DiscussionOur findings suggest that despite individual landowner management efforts, P. australis has continued to expand substantially throughout Suisun Marsh. Future efforts to treat invasive P. australis may require emphasizing adaptive, collaborative management rather than individual management strategies to ensure the invasive species is eradicated on a large scale to preserve the valued ecosystem functions.

“Blue carbon”, apart from marine humus, includes the carbon (C) stock of coastal ecosystems such as mangroves, saltmarshes, and seagrass meadows, which have been overlooked until recently. Information about the role of coastal wetlands in C sequestration and providing other ecosystem services is still insufficient. In the present study, we assessed the C reserves of soils and vegetation biomass in two complex coastal landscapes (tombolos) located on the coasts of the White and Baltic seas. The soil and plant C stocks were slightly higher at the plot on the Baltic Sea (93.4 ± 46.7 Mg C·ha−1 and 5.22 ± 2.51 Mg C·ha−1, respectively) than at the plot on the White Sea (71.4 ± 38.2 Mg C·ha−1 and 3.95 ± 2.42 Mg C·ha−1, respectively). We attributed the higher values of the C reserved to a warmer climate and less saline water at the plot on the Baltic Sea. Both soil and plant C showed high heterogeneity due to geomorphological complexity and differences in vegetative communities. The Phragmites australis community showed the highest plant biomass and, in some places, high soil C reserves. Allochthonous C contributed to the soil C stock at the site on the White Sea. Though P. australis sequestered more C than other communities, its effect on ecosystem services was mostly negative because the invasion of reeds reduced the biological diversity of the marshes.

Coastal wetlands are among the most productive ecosystems in the world and provide important ecosystem services related to improved water quality, carbon sequestration, and biodiversity. In many locations, wetlands are threatened by coastal development and rising sea levels, prompting an era of tidal wetland restoration. The creation and restoration of tidal marshes necessitate the need for ecosystem monitoring. While satellite remote sensing is a valuable monitoring tool; the spatial and temporal resolution of imagery often places operational constraints, especially in small or spatially complex environments. Unoccupied aircraft systems (UAS) are an emerging remote sensing platform that collects data with flexible on-demand capabilities at much greater spatial resolution than sensors on aircraft and satellites, and resultant imagery can be readily rendered in three dimensions through Structure from Motion (SfM) photogrammetric processing. In this study, UAS data at 5 cm resolution was collected at an engineered wetland at Poplar Island, located in Chesapeake Bay, MD United States five times throughout 2019 to 2022. The wetland is dominated by two vegetation species: Spartina alterniflora and Spartina patens that were originally planted in 2005 in low and high marsh elevation zones respectively. During each survey, UAS multispectral reflectance, canopy elevation, and texture were derived and used as input into supervised random forest classification models to classify species-specific marsh vegetation. Overall accuracy ranged from 97% to 99%, with texture and canopy elevation variables being the most important across all datasets. Random forest classifications were also applied to down-sampled UAS data which resulted in a decline in classification accuracy as spatial resolution decreased (pixels became larger), indicating the benefit of using ultra-high resolution imagery to accurately and precisely distinguish between wetland vegetation. High resolution vegetation classification maps were compared to the 2005 as-built planting plans, demonstrating significant changes in vegetation and potential instances of marsh migration. The amount of vegetation change in the high marsh zone positively correlated with interannual variations in local sea level, suggesting a feedback between vegetation and tidal inundation. This study demonstrates that UAS remote sensing has great potential to assist in large-scale estimates of vegetation changes and can improve restoration monitoring success.

Sanjiang Plain is the most extensive marsh distribution region in China. Marshes in this region can protect biodiversity, regulate climate, and provide habitats for wild animals and plants. The normalized difference vegetation index (NDVI) is a crucial indicator of vegetation coverage, which may reflect ecosystem structure and functional features. Clarifying the spatiotemporal change of marsh coverage and its climatic drivers is vital for observing and predicting vegetation change in Sanjiang Plain. Using meteorological dataand MODIS NDVI data from 2000 to 2020, we analyzed the spatiotemporal variation in marsh vegetation coverage and climatic change effects in Sanjiang Plain. We found that the growing season vegetation NDVI of marsh increased significantly at a rate of 0.011/decade, indicating that the marsh vegetation growth has obviously improved during the past 21 years. Furthermore, we found that the increase of minimum (Tmin) and maximum (Tmax) temperature in July can significantly promote the marsh plant growth, and increasing nighttime Tmin has a stronger impact on promoting the growth than increasing daytime Tmax in this month. In addition, the increase of daytime Tmax in August can promote the marsh vegetation growth, whereas the increasing precipitation in August was unfavorable for the growth in Sanjiang Plain. [ABSTRACT FROM AUTHOR]

The constant deficiency of water modality will increase the incidence of complaint, predominantly for unguarded people in undeveloped republics, where practical doses and substitutes are not enthusiastically available. Many wetland-reliant on types in many percentages of the ecosphere are in degeneration; the location of kind dependent on domestic waters are of exact uneasiness. The chief deficiency and impairment of rivers, branch, swamplands, and other interior wetlands have been occupant's expansion and increasing financial development. The key deficiency and impairment include infrastructure development, land alteration, water removal, pollution, and the plan of offensive eccentric categories. Agronomical governments and approaches have applied a widespread diversity of characteristically conflicting properties on exclusive and coastal wetlands globally. The foremost the impairment and deficiency of wetlands, including seawater swamplands have been revision to other earthly practices. The most important changes were the development of anthropological populations in the coastal areas and the increase in economic activity. The destruction and dissolution of wetlands, an important route of travel, has endangered many species and injured others. Global climate change is estimated to increase the damage and deprivation of many wetlands, as well as the damage or degradation of their species, and harm the anthropological inhabitants who depend on the facility. Many wetlands change as a result of estimated sea level rise, increased storm surges and storm surges, variability in storm surge concentration and frequency, and fluctuations in waterway flow and sediment flow. The effects of global climate change often amplify the effects of wetland withdrawal. It is well known why many types of wetlands, such as lakes and wetlands, are relocated, transformed, or looted, but the benefits of their conservation are often greater than the benefits associated with their alteration. It will be bigger. In wetland conservation, indigenous peoples have often been excluded from the decision-making process. Decisions at many stages ignore the relationship between wetland conditions and the establishment of wetland facilities, and the resulting benefits to the individual. Many of the amenities supported by wetlands are unfunded and are accumulated in civilizations on a national and global scale. The benefits of transforming wetlands include those that stimulate wetland drainage for agriculture and those that stimulate important wetlands through intensive organizations that include advances in municipalities, manufacturing and recreational industries. It is repeatedly exaggerated by money. With the results in mind, high-level potential hazards and zones with different hazard levels and management approaches have been proposed for this wetland. [ABSTRACT FROM AUTHOR]

Here we present an investigation with the aim of reconstructing the shoreline evolution and geomorphological changes in the central zone of Samborombón bay (Channel 15, Buenos Aires province, Argentina) during the period 2700 cal yr BP to recent times. Palynological, geomorphological and historical imagery and proxy-data analyses were combined to reconstruct the shoreline evolution and paleo-environmental changes. Palynological material (pollen and non-pollen palynomorphs -NPP-) was recovered from a continuous 117 cm long sedimentary profile extracted from an outcrop at the northern margin of Channel 15. Relict landforms, including paleo- shorelines, were reconstructed by applying enhancing filters to a Spot 6 image from 2015. Historical shorelines were identified in high-definition images (aerial and satellite imagery) between 1968 and 2018, but also by using the marsh vegetation edge as a shoreline proxy. Shoreline change was quantified using the Net Shoreline Movement and Weighted Linear Regression algorithms in ArcMap 10.1. Results based on the palynological analysis for the period 2700–2740 BP, show the passage from subtidal-intertidal to supratidal environment with influence of brackish to fresh-waters, where paleo-shorelines imprint was recognized developing over a tidal plain that was grading to marshes. Results based on aerial and satellite imagery for the period 1968–2018 show shoreline retrocession only immediately at the north of the channel mouth, while the rest of the coast prograded toward the estuary. These processes indicate that new marshes – and, therefore, wetlands – are constantly developing at the edge of Samborombón bay. [ABSTRACT FROM AUTHOR]

To stop the worldwide decline of wetlands, conservation measures like restoration, protection and construction of these ecosystems are indispensable. However, wetland conservation could influence mosquito populations. We analysed how conservation measures affect the species composition and abundance of mosquitoes by conducting a systematic literature review and generated results from 113 selected articles. Thereby, we separately assessed conservation measures in constructed, for example polders, and natural, non-constructed, wetlands. An increase in overall mosquito abundance was more prevalent in constructed wetlands, but not in studies conducted in non-constructed wetlands. Besides assessing overall mosquito abundance, we developed a scheme to rank mosquito species-specific nuisance after conservation measures. Mosquito species can differ in their nuisance potential according to their biting and host-seeking behaviors. We further assessed the effects of mosquito management practices on specific mosquito species and discussed different practices between constructed and non-constructed wetlands. Whereas in constructed wetlands more management practices could be applied, practices in non-constructed wetlands were limited. In conclusion, we were not able to reject entirely the hypothesis that mosquito populations change after conservation measures in wetlands. [ABSTRACT FROM AUTHOR]

Background and Aims: The immunohistochemical application of CD3 (T lymphocytes) and CD20 (B lymphocytes) markers in duodenal biopsy can facilitate the detection of the number and distribution of intraepithelial lymphocytes along the villi, which is regarded as a key factor for accurate diagnosis of celiac disease. This study aims at finding a relationship between CD3 and CD20 immunohistochemical and histopathological alterations of celiac disease, and at investigating whether the application of those immunohistochemical stainings would improve the detection of lymphocytosis within the epithelium and add advantages to celiac disease diagnosis. Methods: Biopsies were obtained from 100 individuals and stained with hematoxylin and eosin (H&E). They were then evaluated according to the Marsh classification. After that, staining for CD3 and CD20 was individually done and assessed. Results: The overall mean intraepithelial lymphocyte count per 100 enterocytes for H&E was 23.1 (95% confidence interval [CI] = 19.52–26.68), and for immunohistochemistry by CD3 and CD20 was 27.84 (95% CI = 24.31–31.38). The difference was highly significant, P = 0.001. The expression of CD3 immunohistochemically was as follows: Less‐than‐half staining pattern was reported in 16% cases, and half staining pattern was seen in 26%, while most cases 58% had more than half staining pattern. This discovery was consistent with the histological classification of March III among most cases. The expression of CD20 immunohistochemically was as follows: mild crypt involvement was observed in 16% of cases, while moderate crypt involvement and intense crypt involvement were seen in 43% and 41% of cases, respectively. [ABSTRACT FROM AUTHOR]

The phenology of Laguncularia racemosa (L.) Gaertn. (Combretaceae) was investigated from a population located near the species' northeastern range limit in Florida. Height, leaf dimensions, and the number of flower buds, flowers, and propagules were recorded, on average, every 2–3 months from May 2021 to October 2023. Irradiance, temperature, and inundation depth were measured hourly with data loggers and compared among seasons and years. Although plant heights were negatively impacted by freeze events in 2022 due to defoliation, vertical growth rates were significantly greater following the freeze. Flower bud and flower production were observed during the summer months and differed among years with greater abundances in 2021. Propagules were recorded in summer and autumn with greater abundances in 2021 and 2022 than in 2023. Light intensity was unlikely to limit growth without a canopy of L. racemosa. Maximum inundation depths > 1.2 m were recorded in autumn and winter when propagule dispersal was likely to occur. The greatest depth of 2.2 m was more than the tallest individual in the study and occurred when hurricanes coincided with extreme high tides. The L. racemosa population was resilient to freeze and flooding events suggesting that population densities may continue to increase in northeastern Florida marshes. • The phenology of Laguncularia racemosa was investigated in northeastern Florida. • Following freeze events significant defoliation occurred. • Environmental cues for flower and propagule production were similar to southern populations. • Laguncularia racemosa was resilient to freeze and flooding events. [ABSTRACT FROM AUTHOR]

This study investigates the use of small unoccupied aerial systems (sUAS) as a new remote sensing tool to identify and track the spatial distribution of wrack on coastal tidal marsh systems. We used sUAS to map the wrack movement in a Spartina alterniflora-dominated salt marsh monthly for one year including before and after Hurricane Isaias that brought strong winds, rain, and storm surge to the area of interest in August 2020. Flight parameters for each data collection mission were held constant including collection only during low tide. Wrack was visually identified and digitized in a GIS using every mission orthomosaic created from the mission images. The digitized polygons were visualized using a raster data model and a combination of all of the digitized wrack polygons. Results indicate that wrack mats deposited before and as a result of a hurricane event remained for approximately three months. Furthermore, 55% of all wrack detritus was closer than 10 m to river or stream water bodies, 64% were within 15 m, and 71% were within 20 m, indicating the spatial dependence of wrack location in a marsh system on water and water movement. However, following the passing of Isaias, the percentage of wrack closer than 10 m to a river or creek decreased to a low of 44%, which was not seen again during the year-long study. This study highlights the on-demand image collection of a sUAS for providing new insights into how quickly wrack distribution and vegetation can change over a short time.

Controlling non-native plant invasions that reduce the quality of preferred wetland habitats is a challenge for many wetland managers. Herbicides may be used to control invasions, but it may be difficult to find effective application methods depending on the terrain. Manned aircraft cover large patches, but aerial use is limited by high costs, weather conditions, and overspray concerns. Ground applications target smaller patches, but their effectiveness may be limited by accessibility, labor costs, and applicator health concerns. Considering these difficulties, unmanned aerial systems (UAS) have emerged as a viable alternative for more effectively treating plant invasions. We tested the use of a specialized UAS to control invasive perennial pepperweed (Lepidium latifolium) in Suisun Marsh in northern California, USA. This “spray drone” flew at an altitude of 2–3 m, a speed of 24 kmph, and applied herbicide with a swath width of 6 m. We applied herbicide with the spray drone to treat small patches before they expanded. To delineate invasive patch boundaries, we first flew a survey drone with a 4K resolution camera to detect emerging plants with color imagery and conduct an initial classification analysis. We subsequently visited areas with suspected invasive patches based on the classification, and observers manually confirmed the presence of the invasive species. We then flew the spray drone on transects to treat the patches and examined the results with post-treatment survey drone imagery and plots along ground transects. In total, we sprayed 14 ha of Lepidium across eight sites and found that 87% of the Lepidium was discernibly affected by our herbicide treatment. Furthermore, we measured the overspray, which was substantially less than that reported for other aerial application methods such as helicopter-spraying, and our estimated operational costs were lower. Our results indicated that applying remote-sensing imagery for the identification of invasive species patches and the use of a spray drone for treatment may be an effective means of controlling invasive plants with high precision at a reasonable cost. In the near future, a unified UAS system that both identifies invasive species and then treats them in a single pass should be a promising goal for early detection and rapid response in wetland management.

This work studies the representativeness of natural ecosystems in the territory of natural reserves of the Zhytomyr region: Natural Reserve «Drevlyansky» and Polesye Natural Reserve, the status and significance of natural ecosystems, in particular terrestrial (forest) and freshwater (rivers and marshes). The main problems of protection and preservation of the presented natural ecosystems in the territory of the nature reserves of Zhytomyr Polesye are considered. It has been established that the area of the natural-reserved fund of the Zhytomyr region increased during the last decade and, hence, there is the increase in ecosystems; the dynamics of its structure has been analyzed but the indicator of the reserve in the region, which is 4,5 %, remains rather low compared to other regions of Ukraine, with the general indicator of 6,6 % through the country. Besides, it has been established that the anthropogenic changes in the area of wetlands are progressing and there is the lack of effective measures for forest ecosystems. When comparing the areas of the territories, on which the natural ecosystems of the reserves are based, significant fluctuations of some natural ecosystems over the others over the proportion of particle size have been established; therefore, it is necessary to ensure the restoration of the key elements of the ecosystems that have been destroyed and maintained under the existing natural ecosystems of the reserves.

Examining vegetation aboveground biomass (AGB) changes is important to understanding wetland carbon sequestration. Here, we combined the field-measured AGB data (458 samples) from 2009 to 2021, moderate resolution imaging spectroradiometer reflectance products, and climatic data to reveal the AGB variations of marshes in Northeast China by comparing various models driven by different indicators. The results indicated that random forest model driven by six vegetation indices, land surface temperature, and land surface water index achieved accurate marsh AGB estimation with R2 being 0.78 and relative error being 16.71%. The mean marsh AGB in Northeast China from 2000 to 2021 was 682.89 ± 31.69 g·m−2, which generally increased from north to south in space. Temporally, annual marsh AGB declined slowly at a rate of 3.45 g·m−2·year−1 during the past 21 years driven mainly by the decrease in summer mean temperature that was characterized by a significantly positive correlation between them. Nevertheless, we highlighted that the temporal changes of marsh AGB spatially varied in response to inconsistent climate change, thus place-based measures are required for sustainable management of marshes.

Barrier islands and their associated backbarrier environments protect mainland population centers and infrastructure from storm impacts, support biodiversity, and provide long-term carbon storage, among other ecosystem services. Despite their socio-economic and ecological importance, the response of coupled barrier-marsh-lagoon environments to sea-level rise is poorly understood. Undeveloped barrier-marsh-lagoon systems typically respond to sea-level rise through the process of landward migration, driven by storm overwash and landward mainland marsh expansion. Such response, however, can be affected by human development and engineering activities such as lagoon dredging and shoreline stabilization. To better understand the difference in the response between developed and undeveloped barrier-marsh-lagoon environments to sea-level rise, we perform a local morphologic analysis that describes the evolution of Long Beach Island (LBI), New Jersey, over the last 182 years. We find that between 1840 and 1934 the LBI system experienced landward migration of all five boundaries, including 171 meters of shoreline retreat. Between the 1920s and 1950s, however, there was a significant shift in system behavior that coincided with the onset of groin construction, which was enhanced by beach nourishment and lagoon dredging practices. From 1934 to 2022 the LBI system experienced ~22 meters of shoreline progradation and a rapid decline in marsh platform extent. Additionally, we extend a morphodynamic model to describe the evolution of the system in terms of five geomorphic boundaries: the ocean shoreline and backbarrier-marsh interface, the seaward and landward lagoon-marsh boundaries, and the landward limit of the inland marsh. We couple this numerical modeling effort with the map analysis during the undeveloped phase of LBI evolution, between 1840 and 1934. Despite its simplicity, the modeling framework can describe the average cross-shore evolution of the barrier-marsh-lagoon system during this period without accounting for human landscape modifications, supporting the premise that natural processes were the key drivers of morphological change. Overall, these results suggest that anthropogenic effects have played a major role in the evolution of LBI over the past century by altering overwash fluxes and marsh-lagoon geometry; this is likely the case for other barrier-marsh-lagoon environments around the world.

Nest predation is the main cause of nest failure for ducks. Understanding how habitat features influence predator movements may facilitate management of upland and wetland breeding habitats that reduces predator encounter rates with duck nests and increases nest survival rates. For 1618 duck nests, nest survival increased with distance to phragmites (Phragmites australis), shrubs, telephone poles, human structures, and canals, but not for four other habitat features. Using GPS collars, we tracked 25 raccoons (Procyon lotor) and 16 striped skunks (Mephitis mephitis) over 4 years during waterfowl breeding and found marked differences in how these predators were located relative to specific habitat features; moreover, the probability of duck nests being encountered by predators differed by species. Specifically, proximity to canals, wetlands, trees, levees/roads, human structures, shrubs, and telephone poles increased the likelihood of a nest being encountered by collared raccoons. For collared skunks, nests were more likely to be encountered if they were closer to canals, trees, and shrubs, and farther from wetlands and human structures. Most predator encounters with duck nests were attributable to a few individuals; 29.2% of raccoons and 38.5% of skunks were responsible for 95.6% of total nest encounters. During the central span of duck nesting (April 17–June 14: 58 nights), these seven raccoons and five skunks encountered >1 nest on 50.8 ± 29.2% (mean ± SD) and 41.5 ± 28.3% of nights, respectively, and of those nights individual raccoons and skunks averaged 2.60 ± 1.28 and 2.50 ± 1.09 nest encounters/night, respectively. For collared predators that encountered >1 nest, a higher proportion of nests encountered by skunks had evidence of predation (51.9 ± 26.6%) compared to nests encountered by raccoons (22.3 ± 17.1%). Because duck eggs were most likely consumed as raccoons and skunks opportunistically discovered nests, managing the habitat features those predators most strongly associated with could potentially reduce rates of egg predation. [ABSTRACT FROM AUTHOR]

Scope: Biochemistry is an essential yet undervalued aspect of soil ecology, especially when analyzing soil C cycling. We assume, based on tradition, intuition or hope, that the complexity of biochemistry is confined to the microscopic world, and can be ignored when dealing with whole soil systems. This opinion paper draws attention to patterns caused by basic biochemical processes that permeate the world of ecosystem processes. From these patterns, we can estimate activities of the biochemical reactions of the central C metabolic network and gain insights into the ecophysiology of microbial biosynthesis, growth, and maintenance energy requirements: important components of Carbon Use Efficiency (CUE). Observations: We show that glucose is processed via the Embden-Meyerhof-Parnas glycolysis in one soil, but via Pentose Phosphate or Entner-Doudoroff pathways in two other soils. However, notwithstanding this metabolic diversity, glucose use efficiency is high and thus substrate use for maintenance energy and overflow respiration is low in these soils. These results contradict current dogma, based on four decades of debate in soil ecology, that the maintenance energy demand in soil communities is a quantitative important, although variable, component of soil community energy metabolism. Conclusions: We identify three main shortcomings in our current understanding of substrate use efficiency: 1) in numeric and conceptual models, we lack appreciation of the strategies that microbes employ to quickly reduce energy needs in response to starvation; 2) in order to understand variation in CUE, we need to improve our understanding of the processes of exudation (including all changes in allocation of C from the cell soluble to insoluble fraction and extracellular environment) and microbial turnover; and 3) whether tracer experiments can be used to measure the long-term substrate use efficiency of soil microbial communities depends critically on the ability and speed with which non-growing cells take up tracer substrates and metabolism activates and subsequently de-activates in response to starvation, as well as on how cellular activities scale to the community level. To move the field of soil ecology forward, future research must consider the details of microbial ecophysiology and develop new tools that enable direct measurement of microbial functioning in intact soils. We submit that 13C metabolic flux analysis is one of those new tools. [ABSTRACT FROM AUTHOR]

The Sanjiang Plain includes the largest freshwater marsh in China, playing an important role in regional carbon cycle. As an important indicator of carbon cycle, the net primary productivity (NPP) is a crucial index for estimating the carbon storage of marshy wetlands. Investigating the association between climate factors and NPP variation quantitatively is of great significance for estimating carbon sequestration of marsh. Based on NPP data and climatic data from 1954 to 2014, the spatiotemporal change of NPP in marsh area was analyzed and its association with climate factors was investigated in the Sanjiang Plain in this study. The results indicated that the NPP showed an increase trend in the marsh area of the Sanjiang Plain in the past six decades. Temperate growth made the largest contribution to the NPP increase among the main climate factors in the last six decades, followed by CO2 concentration. Solar Radiation had the largest explanatory power on the spatial distribution of NPP among three climate factors before 1985. After 1985, temperature played an important role in leading the NPP distribution. Results also showed that the explanatory power of interactions between climate factors was stronger than that of single factor. Our results highlight the asymmetric effects of interactions between climate factors on marsh vegetation, which should be adequately considered in estimating carbon sequestration in marsh area in the Sanjiang Plain.

Inner Mongolia has a large area of marsh wetland in China, and the marsh in this region is important for maintaining ecological balance. Understanding variations in vegetation phenology of marsh ecosystems and their responses to climatic change is crucial for vegetation conservation of marsh wetlands in Inner Mongolia. Using the climate and NDVI data during 2001–2020, we explored the spatiotemporal changes in the start (SOS), end (EOS), and length (LOS) of vegetation growing season and analyzed the effects of climate change on vegetation phenology in the Inner Mongolia marshes. Results showed that SOS significantly (p < 0.05) advanced by 0.50 days/year, EOS significantly delayed by 0.38 days/year, and thus LOS considerably increased by 0.88 days/year during 2001–2020 in marshes of Inner Mongolia. Warming temperatures in winter and spring could significantly (p < 0.05) advance the SOS, and increased summer and autumn temperatures could delay EOS in Inner Mongolia marshes. We found for the first time that daytime maximum temperature (Tmax) and night minimum temperature (Tmin) had asymmetric effects on marsh vegetation phenology. Increasing Tmax had a stronger advancing effect on SOS than increasing Tmin from December to April. The increase of Tmin in August could obviously delayed EOS, while increasing Tmax in August had no significant effect on EOS. This study highlights that the asymmetric influences of nighttime and daytime temperatures should be taken into account in simulating marsh vegetation phenology in temperate arid and semi-arid regions worldwide, particularly in the context of global asymmetric diurnal warming.

Here we present findings from a natural experiment to better understand coastal wetland plant community responses to rising water levels. Plant communities were monitored in three vegetation zones (submergent, emergent, and wet meadow) at Allouez Bay, a lacustrine coastal marsh, six times over years 2011–2020. Lake Superior water levels reached record-highs in 2017, and again in 2019. During our six sampling campaigns, we encountered eighty-four vascular plant species, seven of which were non-native. Except for reductions in total plant cover in the wet meadow zone, emergent and wet meadow plant communities were only marginally affected by rising water. Percent cover of non-native species did not increase in a clear pattern. Temporal changes in floristic quality were non-significant at the whole site level, and mean coefficient of conservatism values ranged from 5.3 to 6.0. Aquatic vegetation in the submergent zone was most affected by rising water. Submergent zone richness declined from sixteen plant species in 2011 to zero in 2020. Multivariate PERMANOVA analysis showed significant effects of year on site-wide plant composition. Temporal composition changes were predominately driven by species turnover in the submergent vegetation zone, whereby floating aquatic species were replaced by non-floating species from 2011 to 2017, and an absence of aquatic vegetation along research transects in 2020. Tracking regeneration of aquatic vegetation is a focus of future research as unknown effects from prolonged exposure to record-high water levels may affect natural regenerative processes at Allouez Bay, and potentially at other lacustrine Great Lakes wetlands throughout the basin. [ABSTRACT FROM AUTHOR]

The Kastrouli Late Bronze settlement in Phocis province, central Greece, has been proved to have been an important center in the periphery of the Mycenaean palaces. It was reused at least partially and was cultivated until the 20th century. The presence of a flat area off the Kastrouli hill and the seasonal flooding nowadays led to the present investigation, questioning the formation of an ancient lake or marsh/swamp. A methodological approach was applied combining the digital elevation model (DEM) and GIS of the wider and confined area, examining slopes between 0 and 5 degrees (0 and 8.75%), with electrical resistivity tomography (ERT) traverses of around 300 and 500 m, reaching a depth of 100 m. The ERT data were rapidly collected on profiles and provided a cross-sectional (2D) plot. It was found that, in the area, there is a basin with a length of 100 m and a depth of around 40–50 m. The sedimentation process over the millennia has filled the basin, with the upper 5–6 m surface layers of the area having a low resistivity. The presence of two natural sinkholes with apparent engineered hydraulic works is noted to conform to drainage and produce a habitable environment, protecting the cultivated land and avoiding a swamp associated with health issues. [ABSTRACT FROM AUTHOR]

Located in Oconto County, Wisconsin, Oconto Marsh #2 is a Great Lakes Coastal Wetland Monitoring Program study site that borders the shoreline of Lake Michigan. Plant communities were characterized at Oconto Marsh #2 along three transects in 2011, 2016, 2017 and 2021, a period when Lake Michigan water levels increased by two meters. Transects were placed to intersect with three vegetation zones: submergent, emergent, and wet meadow. Here, we report on physical landscape changes and the vegetation composition changes that occurred from 2011 to 2021. From satellite imagery interpretation, we show approximately 61,000 m2 of what was emergent and wet meadow vegetation in 2011, transitioned into a submerged aquatic community in 2021. High energy wave action penetrating farther landward, a consequence of higher water levels, is likely most responsible for causing these changes. Plant species richness was lowest in 2011 (32 species) and ranged from 52 to 56 taxa in later years. Using multivariate ordination and PERMANOVA, we show plant composition in 2011 was different from 2016, 2017, and 2021. While invasive Phragmites australis was treated with herbicide in 2014, disturbance from progressively increasing water levels has facilitated considerable changes in plant composition and wetland zone extents since monitoring began. Despite successful treatment of P. australis, encounters with more non-native species while sampling farther landward in later years has caused site-wide declines in multiple metrics of floristic quality. Of critical importance, in 2021, we discovered invasive Hydrocharis morus-ranae at the site, the first documentation in the state of Wisconsin. [ABSTRACT FROM AUTHOR]