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Non-surgical bleeding is a common complication in patients on continuous flow left ventricular assist device (CF-VAD) support. Angiopoietin-2 (ANGPT-2) and von Willebrand Factor (VWF) are important contributors to non-surgical bleeding. 

Abstract Pulses of resource availability along environmental gradients can filter the local and regional distribution of macrophyte and microbial mat communities in wetlands. Wetlands that experience short hydroperiods (i.e., <6 months with standing water) may cause macrophyte and microbial mat competition for water. However, the stress gradient hypothesis predicts that abiotic stress should increase facilitative co‐regulation of producer dynamics. To determine if and how macrophyte and microbial mat biomass covary along a hydrologic gradient, we conducted two observational surveys and a biomass removal experiment in Everglades National Park, FL, USA. In the survey, macrophyte and microbial mat biomass were measured over a two‐year period across nine hydrologically regulated macrophyte community types to determine drivers of biomass and macrophyte–microbial mat interactions along a hydroperiod gradient (3–8 months) using a structural equation model. In the experiment, the effect of hydrology on the interaction between macrophytes and microbial mats was quantified by measuring the effect of bimonthly removal of macrophyte or microbial mat biomass on the biomass of both communities in plots in wetlands with contrasting hydroperiods (3–6 months). Hydrology and biological interactions influenced macrophyte and microbial mat biomass, with stronger interactions observed in the shortest hydroperiod transect sites dominated bySchoenus nigricansandCladium jamaicense. Along the hydrologic gradient, we found direct negative effects of macrophyte biomass on microbial biomass and vice versa, and a significant positive effect of microbial response to flooding duration on macrophyte biomass. Experimental macrophyte removal in shorter‐hydroperiod wetlands resulted in a significant increase in microbial biomass while microbial mat removal reduced biomass of the dominant macrophyteC. jamaicense. The facilitative effect of microbial mats on macrophyte biomass in shorter‐hydroperiod wetlands may be driven by mats prolonging soil moisture retention due to their desiccation‐resistant structure. Stress‐induced facilitation supported the stress gradient hypothesis across the short‐hydrologic gradient, while competitive interactions were also observed. As climate and human drivers continue altering hydrology in aquatic systems, the type and strength of community interactions will continue to shift and alter distributions across the landscape. 

This data package encompasses hydrologic variables, soil depth, hydrologically-regulated macrophyte community types, macrophyte biomass and community structure, and microbial mat biomass that was collected in two observational surveys and one in-situ experimental manipulation in six temporary wetland regions located in the Everglades, FL, USA. The goal of this project was to examine the co-variation in macrophyte and microbial mat biomass along the hydrologic gradient present across wetland regions and to determine the type and strength of interactions occurring between the two communities, which was tested using a biomass (macrophyte or microbial mat) removal experiment. The census observational survey took place at 140 sites from 2003-04-09 to 2004-05-26, which were randomly distributed across the hydrologic gradient present across the six temporary wetland regions. The transect observational survey occurred along six transects and each was deliberately established along the present hydrologic gradient within each region; a total of 254 sites were sampled from 2003-02-19 to 2005-03-04. The experiment took place at three temporary wetland sites with contrasting hydroperiods (3 – 6 months), and four transects were established per site with 24 pairs of control and treatment plots per transect. The removal treatment occurred one year before data collection, and data collection occurred from 2004-06-20 to 2006-11-25. The package includes six datasets, one R code file, and two shape files associated with the R code. Data collection for all datasets is complete. FCE1274_Census_Survey includes hydrologically-regulated macrophyte community type classifications, macrophyte biomass, microbial mat ash-free dry mass, mean soil depth, water depth, mean annual hydroperiod, and vegetation-inferred hydroperiod; each site was sampled once during the survey period and a subset of sites were sampled each year. FCE1274_Transect_Survey includes macrophyte community type classifications, macrophyte biomass, microbial mat ash-free dry mass, mean soil depth, water depth, mean annual hydroperiod, and vegetation-inferred hydroperiod. Each site was sampled once during the survey period; all sites along each transect were sampled before moving to the next transect. FCE1274_Removal_Experiment includes total macrophyte biomass, live macrophyte biomass, dead macrophyte biomass, and live macrophyte stem density within each microbial mat removal control and treatment plot along each transect at all three sites. Microbial mat dry mass, microbial mat ash-free dry mass, microbial mat chlorophyll-a concentration, and microbial mat organic content for each macrophyte removal control and treatment plot along each transect at all three sites are included as well. Data was collected once from each plot during the data collection period, and one pair of macrophyte removal plots and microbial mat removal plots were randomly sampled on a bimonthly basis until all plots had been sampled. FCE1274_Removal_Experiment_Macrophyte_Biomass includes total macrophyte biomass for each macrophyte species found within each microbial mat removal control and treatment plot along each transect at all three sites. Data was collected once from each plot during the data collection period, and one pair of microbial mat removal plots were randomly sampled on a bimonthly basis until all plots had been sampled. FCE1274_Removal_Experiment_Macrophyte_Density includes total macrophyte stem density for each macrophyte species found within each microbial mat removal control and treatment plot along each transect at all three sites. Data was collected once from each plot during the data collection period, and one pair of microbial mat removal plots were randomly sampled on a bimonthly basis until all plots had been sampled. FCE1274_Removal_Experiment_Macrophyte_Codes includes the taxon codes assigned to each macrophyte species identified in the FCE1274_Removal_Experiment_Macrophyte_Biomass and FCE1274_Removal_Experiment_Macrophyte_Density datasets. 

Abstract Aim and QuestionsSea‐level rise has been responsible for extensive vegetation changes in coastal areas worldwide. The intent of our study was to analyze vegetation dynamics of a South Florida coastal watershed within an explicit spatiotemporal framework that might aid in projecting the landscape's future response to restoration efforts. We also asked whether recent transgression by mangroves and other halophytes has resulted in reduced plant diversity at local or subregional scales. LocationFlorida’'s Southeast Saline Everglades, USA. MethodsWe selected 26 locations, representing a transition zone between sawgrass marsh and mangrove swamp, that was last sampled floristically in 1995. Within this transition zone, leading‐ and trailing‐edge subzones were defined based on plant composition in 1995. Fifty‐two site × time combinations were classified and then ordinated to examine vegetation–environment relationships using 2016 environmental data. We calculated alpha‐diversity using Hill numbers or Shannon–Weiner index species equivalents and compared these across the two surveys. We used a multiplicative diversity partition to determine beta‐diversity from landscape‐scale (gamma) diversity in the entire dataset or in each subzone. ResultsMangrove and mangrove associates became more important in both subzones: through colonization and establishment in the leading edge, and through population growth combined with the decline of freshwater species in the trailing edge. Alpha‐diversity increased significantly in the leading edge and decreased nominally in the trailing edge, while beta‐diversity declined slightly in both subzones as well as across the study area. ConclusionsRecent halophyte encroachment in the Southeast Saline Everglades continues a trend evident for almost a century. While salinity is an important environmental driver, species’ responses suggest that restoration efforts based on supplementing freshwater delivery will not reverse a trend that depends on multiple interacting factors. Sea‐level‐rise‐driven taxonomic homogenization in coastal wetland communities develops slowly, lagging niche‐based changes in community structure and composition. 

Abstract Climate change is accelerating sea‐level rise and saltwater intrusion in coastal regions world‐wide and interacting with large‐scale changes in species composition in coastal wetlands. Quantifying macrophyte litter breakdown along freshwater‐to‐marine coastal gradients is needed to predict how carbon stores will respond to shifts in both macrophyte communities and water chemistry under changing environmental conditions.To test the interactive drivers of changing species identity and water chemistry, we performed a reciprocal transplant of four macrophyte litter species in seven sites along freshwater‐to‐marine gradients in the Florida Coastal Everglades. We measured surface water chemistry (dissolved organic carbon, total nitrogen and total phosphorus), litter chemistry (% nitrogen, % phosphorus, change in N:P molar ratio, % cellulose and % lignin as proxies for recalcitrance) and litter breakdown rates (k/degree‐day).Direct effects of salinity and surface water nutrients were the strongest drivers ofk, but unexpectedly, litter chemistry did not correlate with litterk. However, salinity strongly correlated with changes in litter chemistry, whereby litter incubated in brackish and marine wetlands was more labile and gained more phosphorus compared with litter in freshwater marshes. Our results suggest that litterkin coastal wetlands is explained by species‐specific interactions among water and litter chemistries. Water nutrient availability was an important predictor of breakdown rates across species, but breakdown rates were only explained by the carbon recalcitrance of litter in the species with the slowest breakdown (Cladium jamaicense), indicating the importance of carbon structure, and species identity on breakdown rates.Synthesis. In oligotrophic ecosystems, nutrients are often the primary driver of organic matter breakdown. However, we found that variation in macrophyte breakdown rates in oligotrophic coastal wetlands was also explained by salinity and associated seawater chemistry, emphasising the need to understand how saltwater intrusion will alter organic matter processing in wetlands. Our results suggest that marine subsidies associated with sea‐level rise have the potential to accelerate leaf litter breakdown. The increase in breakdown rates could either be buffered or increase further as sea‐level rise also shifts macrophyte community composition to more or less recalcitrant species. 

Fungi play prominent roles in ecosystem services (e.g., nutrient cycling, decomposition) and thus have increasingly garnered attention in restoration ecology. However, it is unclear how most management decisions impact fungal communities, making it difficult to protect fungal diversity and utilize fungi to improve restoration success. To understand the effects of restoration decisions and environmental variation on fungal communities, we sequenced soil fungal microbiomes from 96 sites across eight experimental Everglades tree islands approximately 15 years after restoration occurred. We found that early restoration decisions can have enduring consequences for fungal communities. Factors experimentally manipulated in 2003–2007 (e.g., type of island core) had significant legacy effects on fungal community composition. Our results also emphasized the role of water regime in fungal diversity, composition, and function. As the relative water level decreased, so did fungal diversity, with an approximately 25% decline in the driest sites. Further, as the water level decreased, the abundance of the plant pathogen–saprotroph guild increased, suggesting that low water may increase plant-pathogen interactions. Our results indicate that early restoration decisions can have long-term consequences for fungal community composition and function and suggest that a drier future in the Everglades could reduce fungal diversity on imperiled tree islands. 

Abstract Degradation of wetland ecosystems results from loss of hydrologic connectivity, nutrient enrichment, and altered fire regimes, among other factors. It is uncertain how drivers of wetland ecosystem processes and wetland vegetation communities interact in reversing the ecological trajectory from degraded to restored conditions. We analyzed biogeochemical and vegetation data collected in wetlands of the Florida Everglades at the start of (2015) and during (2018 and 2021) the initial stages of rehydration. Our objectives were to analyze the allocation of carbon and nutrients among ecosystem compartments and correlated trajectories of vegetation community change following rehydration, to identify the drivers of change, including fire, and analyze macrophyte species‐specific responses to drivers. We expected to see changes in vegetation toward more hydric communities that would differ based on wetland baseline conditions and the magnitude of the hydrologic change. During the study period, both length of inundation and surface water depth increased throughout wetlands in the region, and four fires occurred, which affected 51% of the sampling locations. We observed biogeochemical shifts in the wetland landscape, driven by both hydrology and fire. Total phosphorus concentrations in soil and flocculent detrital material decreased, while soil carbon:phosphorus and nitrogen:phosphorus mass ratios increased at sites further away from water management infrastructure. Transitions in vegetation communities were driven by an increase in hydroperiods and by the distinct changes in nutrient concentrations or soil stoichiometric ratios in each subregion. The abundance of macrophyte species typical of short‐hydroperiod prairies strongly decreased, while dominant long‐hydroperiod species, such asEleocharis cellulosa, expanded. Fire facilitated the expansion of thickly vegetated plumes of invasiveTyphaat sites close to the water inflow sources. Overall, restored hydrology shifted vegetation community composition toward higher abundance of long‐hydroperiod species within six years. In contrast, removal of invasive vegetation controlled by soil phosphorus concentrations will likely require long‐term and interactive restoration strategies. 

Foundation species provide habitat to other organisms and enhance ecosystem functions, such as nutrient cycling, carbon storage and sequestration, and erosion control. We focus on freshwater wetlands because these ecosystems are often characterized by foundation species; eutrophication and other environmental changes may cause the loss of some of these species, thus severely damaging wetland ecosystems. To better understand how wetland primary producer foundation species support other species and ecosystem functions across environmental gradients, we reviewed ~150 studies in subtropical, boreal, and temperate freshwater wetlands. We look at how the relative dominance of conspicuous and well-documented species (i.e., sawgrass, benthic diatoms and cyanobacteria, Sphagnum mosses, and bald cypress) and the foundational roles they play interact with hydrology, nutrient availability, and exposure to fire and salinity in representative wetlands. Based on the evidence analyzed, we argue that the foundation species concept should be more broadly applied to include organisms that regulate ecosystems at different spatial scales, notably the microscopic benthic algae that critically support associated communities and mediate freshwater wetlands’ ecosystem functioning. We give recommendations on how further research efforts can be prioritized to best inform the conservation of foundation species and of the freshwater wetlands they support.