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Similar to most wetlands, the Florida Everglades landscape was altered to promote agriculture and human settlement, significantly altering the natural hydrologic regime. Once former agricultural land located within Everglades National Park (ENP), the Hole-in-the-Donut (HID) wetland restoration program became the first mitigation bank project in Florida. The HID program utilized a restoration technique of complete soil removal to effectively eradicate an invasive plant species. This research investigated the effects of the vegetation and soil removal on the hydrologic conditions of the HID, specifically evapotranspiration and water chemistry. Annual evapotranspiration rates were determined for the region using remotely sensed data and compared to the acres restored over a 15-year period. Groundwater and surface waters were collected from both inside the HID and from adjacent areas within ENP for major cations and anions and total nutrient concentrations. Evapotranspiration rates were found to decrease from a mean of 1083.4 mm year−1 in the year 2000 to 891.6 mm year−1 in 2014 as the restored area increased to 4893 acres. Concentrations of ions and nutrients were lower in groundwater and surface water within the restored areas compared to adjacent areas. We conclude that the lack of soil cover (along with reduced evapotranspiration rates) contributed to the lower ion and nutrient concentrations in the surface water and groundwater within the HID. 

Abstract. Geography and associated hydrological, hydroclimate and land-useconditions and their changes determine the states and dynamics of wetlandsand their ecosystem services. The influences of these controls are notlimited to just the local scale of each individual wetland but extend overlarger landscape areas that integrate multiple wetlands and their totalhydrological catchment – the wetlandscape. However, the data and knowledgeof conditions and changes over entire wetlandscapes are still scarce,limiting the capacity to accurately understand and manage critical wetlandecosystems and their services under global change. We present a newWetlandscape Change Information Database (WetCID), consisting of geographic,hydrological, hydroclimate and land-use information and data for 27wetlandscapes around the world. This combines survey-based local informationwith geographic shapefiles and gridded datasets of large-scale hydroclimateand land-use conditions and their changes over whole wetlandscapes.Temporally, WetCID contains 30-year time series of data for mean monthlyprecipitation and temperature and annual land-use conditions. Thesurvey-based site information includes local knowledge on the wetlands,hydrology, hydroclimate and land uses within each wetlandscape and on theavailability and accessibility of associated local data. This novel database(available through PANGAEA https://doi.org/10.1594/PANGAEA.907398; Ghajarniaet al., 2019) can support site assessments; cross-regional comparisons; andscenario analyses of the roles and impacts of land use, hydroclimatic andwetland conditions, and changes in whole-wetlandscape functions and ecosystemservices. 

Abstract Subtropical seagrass meadows play a major role in the coastal carbon cycle, but the nature of air–water CO₂exchanges over these ecosystems is still poorly understood. The complex physical forcing of air–water exchange in coastal waters challenges our ability to quantify bulk exchanges of CO₂and water (evaporation), emphasizing the need for direct measurements. We describe the first direct measurements of evaporation and CO₂flux over a calcifying seagrass meadow near Bob Allen Keys, Florida. Over the 78‐d study, CO₂emissions were 36% greater during the day than at night, and the site was a net CO₂source to the atmosphere of 0.27 ± 0.17 μmol m⁻²s⁻¹(x̅ ± standard deviation). A quarter (23%) of the diurnal variability in CO₂flux was caused by the effect of changing water temperature on gas solubility. Furthermore, evaporation rates were ~ 10 times greater than precipitation, causing a 14% increase in salinity, a potential precursor of seagrass die‐offs. Evaporation rates were not correlated with solar radiation, but instead with air–water temperature gradient and wind shear. We also confirm the role of convective forcing on night‐time enhancement and day‐time suppression of gas transfer. At this site, temperature trends are regulated by solar heating, combined with shallow water depth and relatively consistent air temperature. Our findings indicate that evaporation and air–water CO₂exchange over shallow, tropical, and subtropical seagrass ecosystems may be fundamentally different than in submerged vegetated environments elsewhere, in part due to the complex physical forcing of coastal air–sea gas transfer. 

Wetlands are often vital physical and social components of a country’s natural capital, as well as providers of ecosystem services to local and national communities. We performed a network analysis to prioritize Sustainable Development Goal (SDG) targets for sustainable development in iconic wetlands and wetlandscapes around the world. The analysis was based on the information and perceptions on 45 wetlandscapes worldwide by 49 wetland researchers of the Global Wetland Ecohydrological Network (GWEN). We identified three 2030 Agenda targets of high priority across the wetlandscapes needed to achieve sustainable development: Target 6.3—“Improve water quality”; 2.4—“Sustainable food production”; and 12.2—“Sustainable management of resources”. Moreover, we found specific feedback mechanisms and synergies between SDG targets in the context of wetlands. The most consistent reinforcing interactions were the influence of Target 12.2 on 8.4—“Efficient resource consumption”; and that of Target 6.3 on 12.2. The wetlandscapes could be differentiated in four bundles of distinctive priority SDG-targets: “Basic human needs”, “Sustainable tourism”, “Environmental impact in urban wetlands”, and “Improving and conserving environment”. In general, we find that the SDG groups, targets, and interactions stress that maintaining good water quality and a “wise use” of wetlandscapes are vital to attaining sustainable development within these sensitive ecosystems.