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Anthropogenic impacts on lake and stream water quality are well established but have been much less studied in wetlands. Here we use data from the 2016 National Wetland Condition Assessment to characterize water quality and its relationship to anthropogenic pressure for inland wetlands across the conterminous USA. Water samples obtained from 525 inland wetlands spanned pH from < 4 to > 9 and 3 to 5 orders of magnitude in ionic strength (chloride, sulfate, conductivity), nutrients (total N and P), turbidity, planktonic chlorophyll, and dissolved organic carbon (DOC). Anthropogenic pressure levels were evaluated at two spatial scales – an adjacent scale scored from field checklists, and a catchment scale indicated by percent agricultural plus urban landcover. Pressure at the two spatial scales were uncorrelated and varied considerably across regions and wetland hydrogeomorphic types. Both adjacent- and catchment-scale pressure were associated with elevated ionic-strength metrics; chloride elevation was most evident in road-salt using states, and sulfate was strongly elevated in a few sites with coal mining nearby. Nutrients were elevated in association with catchment-scale pressure but concomitant changes were not seen in planktonic chlorophyll. Acidic pH and high DOC occurred primarily in upper Great Lakes and eastern seaboard sites having low anthropogenic pressure, suggesting natural organic acid sources. Ionic strength and nutrients increased with increasing catchment-scale pressure even in Flats and closed Depression and Lacustrine sites, which indicates connectivity to rather than isolation from upland anthropogenic landuse even for wetlands lacking inflowing streams. [ABSTRACT FROM AUTHOR]

Marker Wadden is a 1000 ha artificial archipelago developed, since 2017, as a novel ecosystem to restore dynamics in a large Dutch freshwater lake with limited natural dynamics. The newly created habitats should, at flyway level, strengthen populations of threatened bird species that depend on dynamic wetlands. The archipelago includes basins with sandbars and mudflats subject to wind tides. Situated at 3 km distance from the mainland, ground predators are lacking. During the first five years of colonization (2017–2021) six pioneer breeding birds represented significant portions (>5%) of national populations. Common Terns (Sterna hirundo) and shorebirds of pioneer habitats were instantly numerous. Ducks and Black-headed Gulls (Chroicocephalus ridibundus) colonized from year two onwards and in year five gulls became the most numerous breeding birds. Staging birds such as ducks (including 13,000 Eurasian Teal [Anas crecca]), shorebirds, and spoonbills (Platalea leucorodia) appeared in internationally important numbers. We conclude that the archipelago indeed has become an important site for breeding and staging birds and at flyway level, especially in the growing season. Therefore, artificial semi-dynamic habitats with mudflats and developed at a sufficiently isolated and large scale, may mitigate losses of natural pioneer habitat in freshwaters. [ABSTRACT FROM AUTHOR]

The inland and estuary wetlands that characterized by different natural environment perform distinctly in soil carbon (C) sink. It was deemed that estuary wetland has a higher organic C accumulation rate than inland wetland, due to its higher primary production and tidal organics input, thus having higher organic C sink capacity. While from CO2 budge in view, whether does the large organic input from tide restrict CO2 sequestration capacity of estuary wetland has not been discussed comparing with inland wetland. In this study, inland and estuary wetlands were selected to study the potential of CO2 sequestration capacity. It was found that inland wetland had most of soil organic carbon (SOC) derived from plant C, which brought remarkable organic C content and nourished higher microbial biomass, dehydrogenase, and β_glucosidase than estuary wetland. The estuary wetland instead accumulated less SOC, a considerable proportion of which came from tidal waters, therefore supporting lower microbial biomass and enzyme activities than that in inland wetland. However, estuary wetland was evaluated having higher capability in SOC mineralization than inland wetland in consideration of soil respiration (SR) and SR quotient. It was concluded that tidal organic C accelerated the SOC mineralization in estuarine wetland, thus weakening the CO2 sequestration. These results implied the importance of pollution control for reservation CO2 sink function in estuarine wetland. [ABSTRACT FROM AUTHOR]

Spatial population synchrony is a key aspect in ecology. Normally, three mechanisms have been identified to explain similar temporal variations in abundance between spatially separated populations: Moran effect, trophic interactions and dispersal. We analysed the spatial synchrony of the abundance of five diving waterfowl species (White-Headed Duck, Black-Necked Grebe, Red-Crested Pochard, Common Pochard and Common Coot) by conducting a monthly census from October 2013 to September 2019 in 34 lakes located in Central Spain. Twenty-eight independent variables related to the hydroperiod, anthropogenic impacts, landscape and structural variables were tested in relation to temporal patterns. Synchronised lakes groups were identified for all species, with differential associations with variables. The variables associated with spatial synchrony were: Distance between lakes (White-Headed Duck and Common Pochard); Natural vegetation area in lakes (Red-Crested Pochard) and Accumulated precipitation until the breeding season (Common Pochard and Common Coot). For Black-Necked Grebe, no variable was associated with the observed temporal patterns. These results provide the first evidence for the mechanisms behind the spatio-temporal synchronisation of diving waterbirds populations in the central Iberian region. [ABSTRACT FROM AUTHOR]

Anaerobics increase resistance to gas transport and microbial activity in flooded soils. This may result in the presence of aerenchyma in the roots of some wetland plants. Increased aerenchyma airspaces enable oxygen to be transported from the above-ground plant parts to the submerged roots and rhizosphere. Nevertheless, there is still a lack of studies linking field experiments and eco-hydrological modeling to the parameterization of the physiological responses of typical wetland plant species to natural flooding events. Furthermore, from the modeling perspective, the contribution of aerenchyma was not sufficiently considered. The goal of this study was to develop and apply an eco-hydrological model capable of simulating various patterns of plant physiological responses to natural flooding events based on key processes of root oxygen diffusion and aerenchyma functioning in a variably-saturated wetland soil environment. Eco-hydrological experiments were conducted accordingly, with surface water level, root-zone soil water content, soil temperature, leaf net photosynthesis rate and root morphology monitored simultaneously in situ at a site dominated by meadow species Deyeuxia angustifolia (Kom.) Y. L. Chang and invaded shrub species Salix rosmarinifolia Linn. var. brachypoda (Trautv.et Mey.) Y.L. Chou in a typical natural floodplain wetland. The results are as follows: (1) Root oxygen respiration rates are strongly correlated with leaf net photosynthesis rates of the two plant types, particularly under flooding conditions during the growing season; (2) Meadow species with a preference for wet microhabitats has a competitive advantage over first-year invading shrub species during flooding events; and (3) an aerenchyma sub-model could improve the eco-hydrological model’s accuracy in capturing plant physiological responses. These findings have the potential to contribute to the management of wetland and its restorations.

Abstract Geographical gradients in species diversity have long fascinated biogeographers and ecologists. However, the extent and generality of the effects of the important factors governing functional diversity (FD) patterns are still debated, especially for the freshwater domain. We examined the relationship between lake productivity and functional diversity of waterbirds sampled from 35 lakes and reservoirs in northern China with a geographic coverage of over 5 million km2. We used structural equation modeling (SEM) to explore the causal relationships between geographic position, climate, lake productivity, and waterbird FD. We found unambiguous altitudinal and longitudinal gradients in lake productivity and waterbird FD, which were strongly mediated by local environmental factors. Specifically, we found (a) lake productivity increased northeast and decreased with altitude. The observed geographic and altitudinal gradients were driven by climatic conditions and nutrient availability, which collectively explained 93% of the variations in lake productivity; (b) waterbird FD showed similar geographic and altitudinal gradients; the environmental factors which had direct and/or indirect effects on these gradients included climate and lake area, which collectively explained more than 39% of the variation in waterbird FD; and 3) a significant (p = .029) causality between lake productivity and waterbird FD was confirmed. Nevertheless, the causality link was relatively weak in comparison with climate and lake area (the standardized path coefficient was 0.55, 0.23, and 0.03 for climate, lake area, and productivity, respectively). Our study demonstrates how the application of multivariate technique (e.g., SEM) enables the illustration of complex causal paths in ecosystems, enhancing mechanistic explanations that underlie the observed broadscale biodiversity gradients.

The Purple Heron is a species of conservation concern in Europe, mainly threatened by the progressive degradation and reduction of wetlands. For future conservation practices, it is of pivotal importance to gather detailed knowledge of its habitat preferences. In June 2018, a nestling of Purple Heron from a sub-Alpine Lake in Northern Italy was equipped with a GPS/GSM device. Habitat selection during the post-fledging period (mid-July to mid-October) was analysed by superimposing the GPS locations to a fine-grained field-based map, discerning 14 habitat classes as well as narrow (<2 m) and wide (≥2 m) ditches. The contours of the home range were defined as the 99% kernel calculated on all the gathered locations, which were successively sub selected only retaining 2,017 locations representing the position of the bird every hour and all day long. Within the home range, the habitat availability was estimated by generating 10,000 random distributions of the locations. We firstly verified whether wide ditches were more frequently used by the heron if compared to narrow ones. Eventually, we calculated the ratio between the number of true and random locations falling into the different habitat classes, obtaining a series of class-specific selection ratios. We found a significant preference towards wide ditches compared to narrow ones. Freshly renewed reedbeds and cattail beds were strongly favoured, while high-bearing sedges and Black Alder were also significantly preferred but with lower indices. All the remaining habitats, including mature reedbeds, were significantly avoided. Our results reinforce the indication that the protection of minor landscape elements as ditches and small patches of wet habitats may be of pivotal importance to foster the long-term conservation of bird communities linked to the residual wetlands of the sub-Alpine belt [ABSTRACT FROM AUTHOR]

Agricultural ponds are a significant source of greenhouse gases, contributing to the ongoing challenge of anthropogenic climate change. Nations are encouraged to account for these emissions in their national greenhouse gas inventory reports. We present a remote sensing approach using open-access satellite imagery to estimate total methane emissions from agricultural ponds that account for (1) monthly fluctuations in the surface area of individual ponds, (2) rates of historical accumulation of agricultural ponds, and (3) the temperature dependence of methane emissions. As a case study, we used this method to inform the 2024 National Greenhouse Gas Inventory reports submitted by the Australian government, in compliance with the Paris Agreement. Total annual methane emissions increased by 58% from 1990 (26 kilotons CH 4 year -1 ) to 2022 (41 kilotons CH 4 year -1 ). This increase is linked to the water surface of agricultural ponds growing by 51% between 1990 (115 kilo hectares; 1,150 km 2 ) and 2022 (173 kilo hectares; 1,730 km 2 ). In Australia, 16,000 new agricultural ponds are built annually, expanding methane-emitting water surfaces by 1,230 ha yearly (12.3 km 2 year -1 ). On average, the methane flux of agricultural ponds in Australia is 0.238 t CH 4 ha -1 year -1 . These results offer policymakers insights into developing targeted mitigation strategies to curb these specific forms of anthropogenic emissions. For instance, financial incentives, such as carbon or biodiversity credits, can mobilize widespread investments toward reducing greenhouse gas emissions and enhancing the ecological and environmental values of agricultural ponds. Our data and modeling tools are available on a free cloud-based platform for other countries to adopt this approach.

In many migratory bird populations, individuals forgo migrating to the breeding grounds for one or more years and instead ‘oversummer’ in non-breeding areas. This behaviour occurs among long-distance migratory shorebirds, typically species exhibiting delayed maturity. As the oversummering areas remain poorly described, conservation strategies will be incomplete even in species experiencing ongoing global declines. Oversummering areas could be a weak link in the chain if they are spatially distinct from non-breeding grounds, and used during critical stages throughout individual’s lifetime. Here, we present a combining study based on (1) GPS-tracking adult Hudsonian godwits Limosa haemastica oversummering in inland South America, (2) two consecutive seasons of surveys to estimate minimum godwit abundance in that area, and (3) analyses of 13 years of shorebird counts based on the Neotropical Waterbird Census (NWC) in Argentina. Godwits arrived at pampa plain wetlands in early May and spent 5–6 months there. We observed godwits in six out of 44 wetlands surveyed, with a minimum of 366 and 746 godwits counted each survey. Based on frequency of occurrence in NWC, oversummering propensity in Argentina was high for three out of nine Nearctic shorebird species, all of which are of international conservation concern. Despite our limited survey effort, we found several hundred godwits that will likely represent only a small fraction of the population oversummering in this region. Given their delayed maturity, many other long-distance migratory shorebirds may spend large portions of their lives in previously undocumented wetlands while deferring migration. These unrecognized oversummering habitats fall outside the scope of today’s conservation efforts for Hudsonian godwits, because they are not spatially nested within the non-breeding grounds, an issue to be studied for other shorebirds. We therefore propose including specific criteria for oversummering areas when designating wetlands of international concern for the conservation of long-distance migratory shorebirds.

The understanding of inland wetlands’ distribution and their level of vulnerability is important to enhance management and conservation efforts. The aim of the study was to map inland wetlands and assess their distribution pattern and vulnerability to natural and human disturbances such as climate change (temperature increase) and human activities by the year 2080. Inland wetland types i.e. forested/shrub, emergent and open water bodies were classified and mapped using maximum likelihood standard algorithm. The spatial distribution pattern of inland wetlands was examined using average nearest neighbor analysis. A weighted geospatial vulnerability analysis was developed using variables such as roads, land cover/ land use (developed and agricultural areas) and climate data (temperature) to predict potentially vulnerable inland wetland types. Inland wetlands were successfully classified and mapped with overall accuracy of about 73 percent. Clustered spatial distribution pattern was found among all inland wetland types with varied degree of clustering. The study found about 13 percent of open water bodies, 11 percent of forested/shrub and 7 percent of emergent wetlands potentially most vulnerable to human and natural stressors. This information could be used to improve wetland planning and management by wetland managers and other stakeholders.

Despite recent advances in wetland studies, ancient wetland deposits are still not well documented, and their facies characteristics are poorly registered. Sedimentary facies and sequence stratigraphic analysis of the Miocene Yecua Formation (Chaco foreland basin, Central Andes, Bolivia) and their comparison to Pantanal‐like modern wetlands provide an insight into their variability, suggesting a facies model for large inland wetlands that developed in a tropical–subtropical climate. Sedimentological features show that clastic, chemical and biological processes in these environments lead to distinguishable lithofacies variations. Six architectural elements are described: (i) muddy sublittoral (FA1); (ii) mixed siliciclastic–carbonate shoreface (FA2); (iii) sand‐flat (FA3) and (iv) mud‐flat (FA4) deposits; (iv) floodplain (FA5); and (vi) simple channel deposits (FA6). The succession is composed of shallowing‐upward parasequences with different facies characteristics caused by climatically‐driven changes of the water level over three orders of magnitude and cyclicity. These cyclic changes reflect a climatic control on the sedimentation. A palaeoclimatic interpretation suggests a generally warm, humid climate with marked rainfall regime changes. The aim of this article is to use this dataset to improve the understanding of depositional elements, lithologies and stratigraphy in tropical–subtropical large inland wetlands. The proposed criteria will help in recognizing inland wetland deposits in other sedimentary basins. [ABSTRACT FROM AUTHOR]

Geographical gradients in species diversity have long fascinated biogeographers and ecologists. However, the extent and generality of the effects of the important factors governing functional diversity (FD) patterns are still debated, especially for the freshwater domain. We examined the relationship between lake productivity and functional diversity of waterbirds sampled from 35 lakes and reservoirs in northern China with a geographic coverage of over 5 million km2. We used structural equation modeling (SEM) to explore the causal relationships between geographic position, climate, lake productivity, and waterbird FD. We found unambiguous altitudinal and longitudinal gradients in lake productivity and waterbird FD, which were strongly mediated by local environmental factors. Specifically, we found (a) lake productivity increased northeast and decreased with altitude. The observed geographic and altitudinal gradients were driven by climatic conditions and nutrient availability, which collectively explained 93% of the variations in lake productivity; (b) waterbird FD showed similar geographic and altitudinal gradients; the environmental factors which had direct and/or indirect effects on these gradients included climate and lake area, which collectively explained more than 39% of the variation in waterbird FD; and 3) a significant (p =.029) causality between lake productivity and waterbird FD was confirmed. Nevertheless, the causality link was relatively weak in comparison with climate and lake area (the standardized path coefficient was 0.55, 0.23, and 0.03 for climate, lake area, and productivity, respectively). Our study demonstrates how the application of multivariate technique (e.g., SEM) enables the illustration of complex causal paths in ecosystems, enhancing mechanistic explanations that underlie the observed broadscale biodiversity gradients. [ABSTRACT FROM AUTHOR]

Tropical wetlands are amongst the most biodiverse ecosystems on Earth and have immense socioecological value. However, tropical wetlands are considered exploitable resources and continue to be drained and converted to other "productive" uses. It is therefore urgent to identify and understand the interactions between various drivers of change triggering degradation of such wetlands. In the present study, we systematically reviewed and analyzed the existing literature on wetlands in two tropical countries namely India and Brazil with special reference to inland wetlands, and proposed a conceptual model illustrating the intricate linkages of such wetlands with different drivers of change. We also developed the Nature Futures' Framework to depict the diverse values of inland wetlands contributing to human wellbeing in the two tropical countries. Findings revealed similar drivers of change triggering the degradation of Indian and Brazilian wetlands. These include changes in climate & land use, population growth, poor land governance due to weak policies, besides other anthropogenic activities such as deforestation, and overexploitation of wetland resources. Among these, land-use change such as agriculture intensification and infrastructure development were the major direct drivers; whereas, institutional and governance factors such as the absence of concrete policy measures were the major indirect drivers threatening the inland wetlands in India and Brazil. Results also revealed some contrasting drivers of change such as illegal human settlements, and land grabbing by the brick industry for Indian wetlands; while, gold mining and intensification of bovine systems for Brazilian wetlands. Our paper also provides an insight into the status of wetland conservation in India and Brazil. We recommend the promotion of community-based conservation practices while adopting sustainable livelihood strategies by the local people for the conservation and wise use of inland wetlands in India and Brazil. The arguments raised in the paper have the potential to assist the stakeholders and/or decision-makers towards implementing sustainable management strategies for inland wetlands in the two countries, and tropical wetlands in general. [ABSTRACT FROM AUTHOR]

The understanding of inland wetlands' distribution and their level of vulnerability is important to enhance management and conservation efforts. The aim of the study was to map inland wetlands and assess their distribution pattern and vulnerability to natural and human disturbances such as climate change (temperature increase) and human activities by the year 2080. Inland wetland types i.e. forested/shrub, emergent and open water bodies were classified and mapped using maximum likelihood standard algorithm. The spatial distribution pattern of inland wetlands was examined using average nearest neighbor analysis. A weighted geospatial vulnerability analysis was developed using variables such as roads, land cover/ land use (developed and agricultural areas) and climate data (temperature) to predict potentially vulnerable inland wetland types. Inland wetlands were successfully classified and mapped with overall accuracy of about 73 percent. Clustered spatial distribution pattern was found among all inland wetland types with varied degree of clustering. The study found about 13 percent of open water bodies, 11 percent of forested/shrub and 7 percent of emergent wetlands potentially most vulnerable to human and natural stressors. This information could be used to improve wetland planning and management by wetland managers and other stakeholders. [ABSTRACT FROM AUTHOR]

Recreational fishing in freshwater ecosystems is a popular pastime in Australia. Although most native fish are endemic, the fauna is depauperate compared to any landmass of similar size. With commercial fishing no longer a major industry in the country's freshwaters, the future sustainability of these ecosystems will depend heavily on the actions of recreational fishers. However, there has been limited focus on the consequences of recreational fishing in freshwaters. There is particularly a dearth of information on the indirect consequences of fishers on the waterbodies they depend on for their sport. After outlining the respective trends in commercial and recreational fishing in Australia as a basis for placing the sport in context, the indirect impacts of fishers on water quality, movement (walking, off-road vehicles), the introduction/translocation of fauna (particularly fish), the dispersal of flora and the transmission of fish disease and pathogens are reviewed. It is concluded that with the decline of commercial fishing, the competition between commercial fin-fishing and recreational fishing is negligible, at least throughout most of the country. It is also concluded that each of the issues addressed has the potential to be detrimental to the long-term sustainability of the freshwater ecosystems that the fishers depend on for their recreation. However, information on these issues is scant. This is despite the current and predicted popularity of freshwater recreational fishing continuing to increase in Australia. Indeed, there has been insufficient quantitative assessment of the impacts to even determine what is required to ensure a comprehensive, adequate and representative protection of these freshwater ecosystems. To underpin the sustainability of inland recreational fishing in the country, it was concluded that research is required to underpin the development and implementation of appropriate policies. The alternative is that the integrity and biodiversity loss of these ecosystems will ultimately result in their collapse before the indirect consequences of recreational fishing have been directly assessed and appropriately protected. However, the lack of protection of wetlands is not restricted to Australia; there is a deficit of freshwater protected areas worldwide. [ABSTRACT FROM AUTHOR]

La avifauna acuática invernal de la ciénaga de Tláhuac fue estudiada de noviembre de 2006 a febrero de 2007; se identificaron 40 especies, 3 de las cuales corresponden a nuevos registros. El área fue utilizada por, al menos, 25 000 aves acuáticas; 5 fueron las especies dominantes: 3 anátidos (Anas clypeata, A. platyrhynchos diazi y Oxyura jamaicensis), 1 ave playera (Limnodromus scolopaceus) y 1 gallareta (Fulica americana). Sobresalió por su abundancia A. platyrhynchos diazi, subespecie endémica y amenazada, ya que los 2 200 individuos observados representan el 4% de la población total estimada. Las especies mejor representadas mostraron una utilización espacial diferencial, con 3 patrones: 1) especies con distribución uniforme (A. clypeata y F. americana), 2) las agrupadas en una sola porción del humedal (A.p. diazi y O. jamaicensis) y 3) aquella con afinidad por 2 porciones del humedal (L. scolopaceus). La ciénega de Tláhuac es un humedal importante para la avifauna de la región; en ella ocurren, durante el invierno, 6 especies protegidas por el gobierno mexicano; sin embargo, existen factores antrópicos que ponen en riesgo su integridad y que hacen necesarias acciones de protección y conservación.The winter waterbirds of the Ciénega de Tláhuac were studied from November 2006 to February 2007; a total of 40 species were observed, with 3 new records. The area was usedby al least 25 000 birds; 5 species were the dominant: 3 anatids (Anas clypeata, A. platyrhynchos diazi y Oxyura jamaicensis), 1 shorebird (Limnodromus scolopaceus) and 1 coot (Fulica americana). The abundance of A. platyrhynchos diazi, a threatened endemic subspecies, was remarkable because the 2 200 individuals observed represent 4% of its population.The best represented species showed a differential spatial use, with 3 patterns: 1) species with homogeneous use (A. clypeata y F. americana), 2) with affinity to a single portion of the wetland (A. p. diazi y O. jamaicensis), and 3) with affinity for both portions of the wetland (L. scolopaceus). The Ciénega de Tláhuac is an important wetland for birds in the region; during the winter 6 species protected by the Mexican Government occur there; however, there are human factors that threaten its integrity, so that protective and conservation actions are necessary.

The Holocene sequence of the Kebara wetlands, a groundwater–surface water interaction zone ecosystem, was studied in a borehole (Core A), retrieved from the eastern trough of the Carmel coast of Israel. A multi-proxy approach was used for environmental reconstruction, and new ages were added for reassessment of the chronology. The fauna (mainly ostracods), flora, and palaeo-salinity estimates indicate marginal wetland that experienced shrinkage and enlargement, reflecting changing hydrological and climatic conditions. New luminescence ages of sediments and radiocarbon dating of terrestrial seeds in the upper part of the sequence provide a more reliable and accurate chronology. The lower part of the core, between about 14,000 and about 7000 BP, indicates mainly wetter conditions, while the upper part, dated to the last 7000 BP, suggests drier conditions in general, with a few wetter episodes. The almost total disappearance of the fauna in the core after about 6000 BP is in agreement with regional climate records that document increasing aridity in the Levant. A comparison of modern δ 18 O and δ 13 C (water and ostracod) values from the Timsah ponds, the present remnants of the wetland, with the values derived from ostracods in the drilling indicates that, like today, the past wetlands were fed mainly by the karstic carbonate-rich Yarkon-Taninnim mountain aquifer. This paper emphasizes the importance of understanding the sources of the water feeding the wetlands for the re-assessment of previous chronology that was based on total organic carbon (TOC) 14 C dating. [ABSTRACT FROM AUTHOR]

Headwater streams and inland wetlands provide essential functions that support healthy watersheds and downstream waters. However, scientists and aquatic resource managers lack a comprehensive synthesis of national and state stream and wetland geospatial datasets and emerging technologies that can further improve these data. We conducted a review of existing United States (US) federal and state stream and wetland geospatial datasets, focusing on their spatial extent, permanence classifications, and current limitations. We also examined recent peer-reviewed literature for emerging methods that can potentially improve the estimation, representation, and integration of stream and wetland datasets. We found that federal and state datasets rely heavily on the US Geological Survey's National Hydrography Dataset for stream extent and duration information. Only eleven states (22%) had additional stream extent information and seven states (14%) provided additional duration information. Likewise, federal and state wetland datasets primarily use the US Fish and Wildlife Service's National Wetlands Inventory (NWI) Geospatial Dataset, with only two states using non-NWI datasets. Our synthesis revealed that LiDAR-based technologies hold promise for advancing stream and wetland mapping at limited spatial extents. While machine learning techniques may help to scale-up these LiDAR-derived estimates, challenges related to preprocessing and data workflows remain. High-resolution commercial imagery, supported by public imagery and cloud computing, may further aid characterization of the spatial and temporal dynamics of streams and wetlands, especially using multi-platform and multi-temporal machine learning approaches. Models integrating both stream and wetland dynamics are limited, and field-based efforts must remain a key component in developing improved headwater stream and wetland datasets. Continued financial and partnership support of existing databases is also needed to enhance mapping and inform water resources research and policy decisions. [ABSTRACT FROM AUTHOR]

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Inland wetlands are numerous in Spain and have been classified in a broad range of categories. At present, the most relevant classification is that applied by River Basin Authorities for the identification of water bodies, according to the EU Water Framework Directive. This typology recognises up to 27 different types of inland lake in Spain. The aims of this paper are to review current knowledge about the evaluation of the ecosystem services provided by inland wetlands, and to present a discussion about two cases that have been subject to economic evaluation. The results obtained highlight the fact that little work has been done in Spain on this topic, thus opening up new lines of research. In particular, a significant amount of work is required to identify and characterize specific ecosystem services provided by wetlands in Mediterranean conditions, which in turn will do a great deal to highlight the importance of their conservation. Editor Z.W. Kundzewicz; Guest editor M.C. Acreman Citation de la Hera, A. Fornés, J.M. and Bernués, M., 2011. Ecosystem services of inland wetlands from the perspective of the EU Water Framework Directive implementation in Spain. Hydrological Sciences Journal, 56 (8), 1656–1666. [ABSTRACT FROM PUBLISHER]

Phragmites australis (Cav.) Trin. ex Steud. (common reed), already one of the world's most widespread plant species, has realized rapid range expansion in coastal wetlands of North America in the past century, but little is known about P. australis range expansion in inland wetland systems. We used genetic analyses, aerial photographs, field surveys, and a greenhouse experiment to study the extent and mechanism of nonnative P. australis invasion of Utah wetlands. We collected and genetically analyzed 39 herbarium samples across the state and 225 present-day samples from northern Utah's major wetland complexes. All samples collected before 1993 and all samples collected outside the major wetlands of northern Utah, including some as recent as 2001, were identified as native (haplotypes A, B, D, and H). Only 10 (4%) of the present-day samples were native, each from small, discrete, low-density stands; the remaining samples were nonnative (haplotype M). Our earliest nonnative sample was collected near the Great Salt Lake in 1993. Around the Great Salt Lake, which contains 40% of Utah's wetlands, P. australis cover has increased from 20% to 56% over the past 27 years-an increase that appears attributable to the nonnative strain. In a 3-month-long greenhouse experiment, the nonnative haplotype grew taller, had more aboveground biomass, and had a greater above- to belowground biomass ratio than the native haplotypes regardless of nitrogen, phosphorus, or water availability. Nonnative P. australis is rapidly invading the wetlands of northern Utah. Areas in Utah where the native P. australis remains should be identified and protected. [ABSTRACT FROM AUTHOR]

The small playa-lakes and other saline wetlands of Monegros, scattered over a dry area with winter cereal monoculture, are threatened by the settlement of new irrigation districts and other kinds of human pressure. Enforcing the protection rules of European Union in these valuable habitats requires, first, their delimitation and monitoring. This article shows how these tasks can be undertaken using remote sensing in conjunction with field observations. A series of Landsat images covering different seasons provided a comprehensive view of these wetlands encompassing their changing facies, hydrologic regime, state of conservation, and functional status. Remotely-sensed data were the primary, and in most cases the only available, source of consistent information. Our approach can help planning and surveying for the implementation of saline wetland protection measures in harmony with the conterminous agricultural areas. [Copyright &y& Elsevier]

The American alligator (Alligator mississippiensis) has made a remarkable recovery throughout its range during the last half-century. In Texas, USA, current inland alligator population and harvest management strategies rely on generalized and often site-specific habitat and population data generated from coastal populations, because it is assumed that habitat and demographic similarities exist between inland and coastal populations. These assumptions have not been verified, however, and no studies have specifically examined inland alligator habitat use in Texas. We quantified alligator habitat use in East Texas during 2003-2004 to address this information gap and to facilitate development of regionally specific management strategies. Although habitat was variable among study areas, alligators used habitats with >50% open water, substantial floating vegetation, and emergent vegetation close (<12 m) to dry ground and cover. Adults used habitats further from dry ground and cover, in open water (75-85%), with less floating vegetation (6-22%) than did subadults, which used habitats that were closer to dry ground and cover, with less open water (52-68%), and more floating vegetation (8-40%). Although habitat use mirrored coastal patterns, we estimated alligator densities to be 3-5 times lower than reported in coastal Texas, likely a result of inland habitat deviations from optimal coastal alligator habitat, particularly in the preponderance of open water and floating vegetation. Our findings that 1) inland habitats varied among sites and did not exactly match assumed optimal coastal habitats, 2) alligators used these inland habitats slightly differently than coastal areas, and 3) inland alligator densities were lower than coastal populations, all highlight the need for regionally specific management approaches. Because alligator populations are influenced by habitat quality and availability, any deviations from assumed optimal habitat may magnify harvest impacts upon inland populations. [ABSTRACT FROM AUTHOR]

The hydrogeomorphic (HGM) wetland assessment method has been developed to provide a much-needed, ecologically-sound means for classifying, assessing, and comparing wetland hydrodynamics and related functions. A first step in using the HGM is the identification of `biogeographical regions' to characterize regional wetland subclasses. I found no attempts to test existing ecoregions or other subclassification methods in the glaciated Great Lakes basin for use with HGM. Two subclassification methods are tested here. One ecosystem classification (based on geology, climate, topography, and other large-scale variables) is compared with a method based solely on the permeability of underlying glacial deposits. Water-level fluctuation, conductivity, and alkalinity were monitored for three years to determine whether differences in hydrodynamics and water chemistry existed between depressional wetlands using either subclassification method. The hydrodynamics of inland wetlands differed significantly between subclasses based on either method. The permeability-based subclasses were also effective in differentiating wetland water chemistry. Aspects of the ecosystem classification, however, provided additional information not accounted for by the permeability-based method. Thus, the ecosystem classification provides better biogeographical regions for use with HGM in the glaciated Great Lakes basin. [ABSTRACT FROM AUTHOR]

Globally, the most widely used wetland classification is that adopted by the contracting parties of the Ramsar Convention, which is the Convention on Wetlands of International Importance especially as Waterfowl Habitat. A review of the Inland Wetland component of this system shows that mixed criteria are used to separate the wetlands, and that not all natural inland wetlands have been addressed. A classification system using landform and hydro-period, which results in 13 primary geomorphically “non-emergent” types for natural wetlands, is proposed to describe the full variety of wetlands at a primary level around the globe, and is suggested to be incorporated as the first-tier of the Ramsar classification. The proposed classification has been designed so wetlands can be described, classified and compared systematically. This paper attempts to reconcile the Ramsar Classification system with the proposed approach. The intention in this paper is not to displace the Ramsar Classification, but rather to indicate its inherent underlying geomorphic structure, and hence re-order its hierarchical framework. This adjustment to the existing classification system would highlight underlying similarities between wetlands so that global comparisons can be more readily made. It also has considerable advantages for a staged, systematic discrimination and classification of the vast array of differing wetlands globally. The use of geomorphic and hydrologic elements as the primary and secondary divisions with the more commonly used Ramsar Classification terms as a tertiary division, provides a logical structure to compare and contrast wetlands globally. [ABSTRACT FROM AUTHOR]

Thoughts about the potential effects of climatic change due to greenhouse warming on hydrophytes and hydrophyte communities in inland still waters of Europe are presented. A distinction is made between permanent and temporary shallow aquatic ecosystems and between freshwater and brackish systems. Potential effects of greenhouse warming on the hydrology and salinity of isolated brackish waters are illustrated with a computer model, simulating several scenario's of climatic change and differently shaped waters. In permanent waters, greenhouse warming may result in an earlier onset of growth of those hydrophytes in which the germination of propagules and the resumption of growth is primarily controlled by temperature. This may occur at the cost of macrophytes that have dormancy mechanisms regulated by environmental cues other than temperature (e.g. photoperiod). In addition, it seems plausible that because of milder winters, some thermophilous aquatic plants spread to the north. Furthermore, in culturally eutrophicated waters, in which the sediment compartment is heavily loaded with organic matter and/or nutrients, a rise in temperature may accelerate nutrient turn-over for several years, resulting in algal blooms and shifts in quality and quantity of macrophyte vegetation. Effects of greenhouse warming on temporary shallow waters will be more complex. Changes in temperature, precipitation and evaporation may lead to larger seasonal fluctuations in the water table and a more frequent or more prolonged period of desiccation. Some hydrophytes can cope with these circumstances, while others withstand desiccation only for a short period. Macrophyte communities may also be affected in an indirect way by periodic desiccation of their habitats. In emerged bottoms the rate of mineralization is probably higher than when overlying water is present. When water returns, a pulse of mineral nutrients may temporarily result in algal blooms and a high turbidity of the water, thus hampering hydrophyte growth. In addition, in isolated brackish waters an increased evaporation may result in larger fluctuations in salinity. In such a harsh environment species diversity of aquatic macrophytes will most probably decline. [ABSTRACT FROM AUTHOR]

The current study highlights some knowledge on the diversity and structure of insect communities and trophic groups living in Sabkha Djendli (semi-arid area of Northeastern Algeria). The entomofauna was monthly sampled from March to November 2006 using pitfall traps at eight sites located at the vicinity of the Sabkha. Structural and diversity parameters (species richness, Shannon index, evenness) were measured for both insect orders and trophic guilds. The canonical correspondence analysis (CCA) was applied to determine how vegetation parameters (species richness and cover) influence spatial and seasonal fluctuations of insect assemblages. The catches totalled 434 insect individuals classified into 75 species, 62 genera, 31 families and 7 orders, of which Coleoptera and Hymenoptera were the most abundant and constant over seasons and study stations. Spring and autumn presented the highest values of diversity parameters. Individual-based Chao-1 species richness estimator indicated 126 species for the total individuals captured in the Sabkha. Based on catch abundances, the structure of functional trophic groups was predators (37.3%), saprophages (26.7%), phytophages (20.5%), polyphages (10.8%), coprophages (4.6%); whereas in terms of numbers of species, they can be classified as phytophages (40%), predators (25.3%), polyphages (13.3%), saprophages (12%), coprophages (9.3%). The CCA demonstrated that phytophages and saprophages as well as Coleoptera and Orthoptera were positively correlated with the two parameters of vegetation, especially in spring and summer. While the abundance of coprophages was positively correlated with species richness of plants, polyphage density was positively associated with vegetation cover. The insect community showed high taxonomic and functional diversity that is closely related to diversity and vegetation cover in different stations of the wetland and seasons.