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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]

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 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]

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]