Search Results (147)

The Guangdong Haifeng Coastal Wetlands (Ramsar Site No. 1727) in Shanwei City are a critical habitat for migratory birds, but the long-term evolution and driving mechanisms of ecological vulnerability under rapid urbanization remain insufficiently understood. In particular, few studies have quantitatively characterized the temporal shifts in the relative roles of anthropogenic pressures and conservation policies over decadal scales. This study developed a landscape pattern-based ecological vulnerability assessment model integrating spatial autocorrelation, Geodetector, the PLUS model, and spatial overlay analysis to diagnose the dynamics and driving mechanisms of the wetlands from 1980 to 2018. The results showed that farmland and woodland dominated Shanwei City, while water bodies consistently dominated the Haifeng Wetlands. Ecological vulnerability exhibited significant spatial heterogeneity, with levels higher in the northwest and lower in the southeast. Forest and water expansion overlapped with vulnerability reduction, whereas built-up and farmland expansion matched increases in vulnerability. Land-use intensity, elevation, and mean annual temperature were identified as the primary drivers. The drivers of built-up land expansion shifted from population-related pressures during 1980–2000 to stronger policy regulation effects after 2000, indicating a transition in human–land interactions. Conservation policies, including nature reserve establishment and Ramsar designation, provided important institutional support for ecological management. These findings highlight the importance of integrating long-term land-use dynamics with natural, socioeconomic and policy contexts to improve the understanding and management of coastal wetlands vulnerability under rapid urbanization. Full article

The Laspias River and Lissos River sustain the hydrological and ecological functioning of the Vistonida Lake wetland complex, a protected Natura 2000 site and Ramsar Convention Wetland of International Importance, by regulating nutrient transport and supporting aquatic biodiversity. Thus, the water quality of the rivers Laspias and Lissos and their adjacent coastal zones located in the prefectures of Xanthi and Rhodope (NE Greece) respectively was monitored regarding key metal concentrations for a period of two years. The monitoring of these watersheds and coastal zones was based on seven sampling stations in the Laspias River, twelve stations in the Lissos River and four stations in each river’s coastal zone. During water monitoring of both rivers, a wide range of chemical elements was analyzed to assess water quality. In the present work, the heavy metal pollution index (HPI) and the heavy metal evaluation index (HEI) were assessed in both rivers and their coastal area for four successive seasons. The mean HPI and HEI values for the Laspias River were 54.66 ± 10.82 and 1.45 ± 0.22, whereas the respective indices in the Lissos River were 14.43 ± 4.14 and 0.39 ± 0.14. The mean HPI and HEI values for the adjacent coastal zones of the Laspias and Lissos Rivers were 7.42 ± 1.52 and 0.14 ± 0.05, as well as 10.39 ± 0.83 and 0.23 ± 0.02, respectively. Therefore, the average HPI values for both rivers and their coastal zones were below the proposed threshold (<100), while the HEI of the Laspias River classified the water quality in the second category (slightly affected, HEI from 1.0 to 2.0 due to the effect of Mn) and the Lissos River in the first category (very pure/pure, HEI < 1), respectively, considering drinking water thresholds. The HEI indices of their coastal zones characterized the water quality as very pure/pure. Full article

Invasive species represent a major threat to global biodiversity, highlighting the need for continuous monitoring and research to better understand their ecology, distribution, and invasion dynamics. Among freshwater leeches (Hirudinea), Helobdella europaea is considered one of the most successful and widespread invasive taxa. This study provides an updated assessment of the distribution of H. europaea in Morocco and identifies the main environmental factors influencing its occurrence and spread across the country. Field surveys were conducted between 2014 and 2024 in northern Morocco, with particular focus on protected wetlands, including Ramsar sites, and major biogeographical barriers such as the Middle Atlas Mountains and the Sebou and Moulouya river basins. Specimens were collected using Surber samplers (20 × 25 cm, 400 μm mesh), while physicochemical water parameters and other abiotic variables were simultaneously recorded. Since its first detection in Morocco in 2014, H. europaea has significantly expanded its geographic range. The species exhibited broad ecological tolerance, occurring in a wide variety of habitats, including environmentally degraded sites, and enduring substantial variation in water conditions. Among the environmental variables examined, water velocity and salinity were identified as the primary factors constraining the species’ distribution and abundance. Nevertheless, additional studies are required to better predict the future expansion dynamics of H. europaea, particularly under ongoing hydrological alterations and climate change scenarios. Full article

Wetlands are vital ecosystems that provide critical provisioning, regulating, cultural, and supporting services that underpin biodiversity conservation and local livelihoods. Despite their importance, ecosystem service valuation is often overlooked in coastal wetland restoration, limiting recognition of their contributions to the United Nations Sustainable Development Goals (SDGs). To address this gap and overcome methodological fragmentation in wetland assessments, this study develops the Integrated Ecosystem Valuation and Management of Wetlands (IEVMW) framework, which integrates the Millennium Ecosystem Assessment (MEA), Drivers–Pressures–State–Impact–Response (DPSIR) framework, IPCC climate risk assessment, and Total Economic Value (TEV) approaches into a unified methodology. The framework was applied to the Kol Wetlands in India to identify ecosystem services, assess climate-related risks, estimate economic values, and develop management recommendations. Results indicate that provisioning services contribute the highest economic value, followed by regulating and cultural services. Climate change was estimated to place approximately 11.7% and 13.0% of ecosystem service value at risk in North Kol and South Kol, respectively, corresponding to a combined economic value at risk of ₹42.9 crore, with provisioning services being the most vulnerable. The IEVMW framework provides a practical and scalable approach for linking ecosystem service valuation, climate risk assessment, and governance, thereby supporting climate-resilient wetland management and biodiversity conservation across diverse socio-environmental contexts. Full article

Introduction: A diverse ichthyofauna is supported by the Lima River in northern Portugal. Despite its ecological significance, Ramsar-protected wetlands status and Natura 2000 site, the system remains among the least studied in the Iberian Peninsula. Objective: This study characterises the fish assemblage of the Lima River and some of its tributaries. It examines the composition and abundance of species, as well as key biological parameters, across the river’s freshwater and estuarine sections. Particular attention is given to the balance between native and exotic taxa, and to the threats facing the native ichthyofauna. Methodology: Between 2021 and 2023, 3242 individuals belonging to 15 species were sampled using fyke nets, trammel nets, and electrofishing at 13 sites along the river system. Results: Native species accounted for 51.1% of the total catch. This comprised resident freshwater taxa, such as Pseudochondrostoma duriense, Achondrostoma oligolepis, Luciobarbus bocagei, Squalius carolitertii, Cobitis atlantica, Gasterosteus aculeatus, and resident Salmo trutta, alongside diadromous species, namely Chelon ramada, Petromyzon marinus, Alosa spp., migrant Salmo trutta and Anguilla anguilla. Exotic species accounted for 48.9% of the total catch, with four non-native taxa being recorded: Lepomis gibbosus, Micropterus salmoides, Carassius auratus and Gobio lozanoi. This reflects the extent of the biological invasion pressure on this system. Analysis of the stomach contents of Salmo trutta revealed active predation of non-native species. Plastic debris was detected in 1.1% of Salmo trutta stomachs, which evidences that anthropogenic pollution has reached freshwater feeding habitats. The first recorded instance of the invasive nematode Anguillicola crassus in the Lima River, where 84.8% of the eels sampled exhibited moderate-to-severe swim bladder damage, highlights the vulnerability of native species to biological invasions. Conclusions: Biometric analyses and condition factors suggest that the fish community is under cumulative anthropogenic stress, caused by factors including river fragmentation due to three dams and traditional fishing weirs. The near-equal representation of native and exotic species in catches indicates that the freshwater fish community is under significant invasion pressure, which has direct consequences for the conservation of the native ichthyofauna. These findings establish a crucial baseline for the evidence-based management of an Iberian river system that is ecologically important but data-poor. Full article

Microplastic contamination in wetland ecosystems is an escalating environmental threat, compromising ecosystem services, biogeochemical cycling and biodiversity conservation. This study assessed the occurrence, distribution and physicochemical characteristics of microplastics in the Ramsar-designated Pallikaranai wetland, southern India. Six representative subsamples were collected from spatially distinct locations and analyzed using density separation, followed by polymer identification via Raman spectroscopy and energy-dispersive X-ray spectroscopy (EDS). Microplastics were ubiquitously detected across both sediment and water matrices, with significantly higher abundances in sediments, indicating their role as a major sink. The dominant polymer types, polyethylene (PE), polypropylene (PP) and polystyrene (PS), along with prevalent morphotypes such as fragments, fibers, beads and foams, reflect diverse and persistent anthropogenic inputs. The compositional profile strongly implicates mismanaged domestic and urban waste as the primary source. The widespread presence and accumulation of microplastics in this ecologically sensitive wetland raise concerns over potential impacts on trophic interactions, habitat quality and long-term ecosystem resilience. These findings underscore the urgent need for targeted waste management strategies, pollution mitigation frameworks and continuous monitoring to safeguard the ecological integrity of the Pallikaranai wetland and similar Ramsar-listed ecosystems. Full article

Floodplains are key components of inland river systems of Australia with floodplain vegetation playing important roles in habitat provision, nutrient cycling, and supporting strong cultural values. These vegetation communities are highly dynamic, particularly in response to flooding. However, decades of water development and highly managed water resources are linked to wetland habitat decline in this region. We explored patterns of vegetation response to flooding over twenty years at the Narran Lakes Ramsar site, a terminal floodplain wetland system in the northern Murray–Darling Basin, Australia. We collated data from previous monitoring efforts and resampled permanent plots for understorey vegetation structure and composition. Three flood events were surveyed over a 20-year period, with each event surveyed on two occasions first, following initial drawdown (minimal standing water) and a second survey under dry or drier conditions (~6 months after the recession of floodwaters). Overall, we observed a high diversity of native plant species (~110 species) in understorey communities across the wetland and high compositional turnover both between flood events and within years (i.e., paired surveys). Notably, vegetation cover, but not species richness, was greatest in the 2023 survey following the largest of the three flood events investigated. Understorey composition was strongly driven by inundation regimes, particularly the duration of recent inundation, and the number of wet and dry years prior. Large flood events are critical for supporting vegetation resilience in these systems, increasingly so under a drier climate and with stretched water resources. Continued long-term monitoring of vegetation through flood cycles at the Narran Lakes will be critical to understanding ecological responses to longer-term changes in climate and hydrology to inform adaptive water management and maintain the values of this Ramsar site. Full article

The Somyne lake-mire system is a unique wetland landscape complex in the Polissia region of Ukraine and forms part of the Rivne Nature Reserve. Its ecological importance is internationally recognised through its designation as the Ramsar wetland “Somyne Peatland Massif”. Effective conservation of this wetland requires an understanding of the factors controlling the functioning of the lake and its drainage basin, considered in this study as a lake-basin system (LBS). The aim of this study is to assess the geoecological condition of the Somyne LBS using the principles of landscape limnology and the basin approach. The research integrates morphological, morphometric, hydrological, landscape-metric, hydrochemical and geochemical analyses. These are complemented by bathymetric modelling, landscape mapping, and analysis of long-term meteorological observations. The results identify key natural and anthropogenic drivers shaping the functioning of the system, characterise the hydrochemical state of lake waters and the geochemical properties of bottom sediments, and describe the spatial distribution of bottom sediments and the bathymetric structure of the lake basin. A multivariate algorithm for the geoecological assessment of lake-basin systems is proposed, providing a framework for comparative analysis of small lakes in the Polissian lake region under climate change and increasing anthropogenic pressure. Full article

Seasonal tropical wetlands such as the Brazilian Pantanal are increasingly threatened by climate variability and extreme hydrological events, creating a need for robust monitoring tools that capture flood dynamics at high spatial and temporal resolution. This study used Sentinel-1 Synthetic Aperture Radar (SAR) imagery to map and monitor flooding in the northern Pantanal, a Ramsar site renowned for its wildlife, between 2017 and 2020. Ground Range Detected (GRD) VV-polarized scenes were preprocessed using radiometric terrain normalization and speckle filtering (Lee filter, 5 × 5 window) to improve the separability of water and non-water surfaces. Flooded areas were initially extracted with Otsu’s histogram thresholding and validated using high-resolution optical imagery (PlanetScope and Landsat-8). A supervised Random Forest classifier then refined land-cover discrimination into three classes (open water/flood, open land/vegetation, and others), achieving an overall accuracy of 97.70% on the independent testing dataset (n = 6622), while temporal consistency was supported by Cuiabá River hydrological data. The results revealed strong interannual variability in flood extent, with inundation covering 34.7% of the reserve in March 2017 compared with 0.75% in March 2020 and reaching a peak of 79.9% in April 2017. Overall, Sentinel-1 SAR effectively delineated open water and flood-affected surfaces under persistent cloud cover, demonstrating its value for complementing existing products such as MapBiomas, strengthening wetland management, and supporting scalable flood monitoring in other tropical flood-prone Ramsar sites. Full article

Wetlands are highly productive ecosystems that play a vital role in maintaining ecological balance. This study presents a geospatial assessment of the Harike Wetland, Punjab, using hyperspectral (PRISMA) and multispectral (Landsat series) satellite data to analyze its ecological structure and water dynamics. Six spectral indices—Normalized Difference Vegetation Index (NDVI), Normalized Dif-ference Aquatic Vegetation Index (NDAVI), Normalized Difference Water Index (NDWI), Modified NDWI (MNDWI), Floating Algal Index (FAI), and Algal Bloom Detection Index (ABDI)—were employed to map terrestrial agricultural cropland (paddy), aquatic vegetation and surface water. Threshold-based classification of index outputs was used to estimate the spatial extent of major land cover types. NDVI and NDAVI effectively captured vegetation patterns, while NDWI and MNDWI improved surface water delineation. Additionally, Z-spectral analysis was applied to extract and compare the reflectance profiles of agricultural cropland, open water, and algae, as well as built-up areas, enhancing spectral contrast and classification accuracy, particularly in spectrally mixed zones. The integration of index-based mapping with detailed spectral profiling demonstrates the advantage of combining multispectral and hyperspectral data for wetland monitoring and provides valuable insights to support wetland conservation and sustainable water management. Full article

Heavy metal pollution from mining activities and urban runoff poses a serious threat to public health and aquatic ecosystems in vulnerable communities around the Bolivia–Peru transboundary Lake Titicaca basin. This study evaluates the use of two abundant wetland plants—totora (Schoenoplectus californicus) and reed (Phragmites australis)—as low-cost, locally available biosorbents for the removal of dissolved iron (Fe²⁺) from the Pallina River, a major contaminant source to Cohana Bay. Monitoring data from Bolivia’s Ministry of Environment and Water (2019–2022) revealed Fe²⁺ concentrations exceeding the national legal limit (0.3 mg/L) by more than 20 times during the dry season. Laboratory experiments using synthetic Fe²⁺ solutions (20 mg/L) optimized biosorption conditions, identifying pH 5, 4–6 g/L biomass, fine particle size (0.15–0.212 mm), and a 3 h contact time as optimal. Both plants followed pseudo-second-order kinetics and Langmuir isotherms. Totora showed superior performance, achieving a maximum capacity of 7.8 mg/g compared to reed’s 2.9 mg/g. Continuous-flow column tests removed up to 95% of Fe²⁺ from synthetic water. When applied to real Pallina River water, totora achieved 50% Fe²⁺ removal despite reduced efficiency due to competing organic matter. The findings demonstrate the potential of totora-based biosorption as a scalable, nature-based solution for transboundary water management. The policy implications of this study are profound under the national and global water and wetland governance mechanisms and transboundary frameworks like the Binational Autonomous Authority of Lake Titicaca (ALT, est. 1996) and Ramsar Convention. Full article

Accurate delineation of stream networks in low-gradient wetlands remains challenging due to subtle topographic variation and dense vegetation cover. This study systematically evaluated 48 Unmanned Aerial Vehicle Light Detection and Ranging (UAV-LiDAR) processing workflows through 1128 pairwise comparisons to identify optimal approaches for mapping fine-scale channels in Japan’s Kushiro Wetland, a Ramsar-designated ecosystem. The workflows combined three ground filtering methods (Progressive Morphological Filter, Cloth Simulation Filter, Multiscale Curvature Classification), four interpolation techniques (Inverse Distance Weighting, Triangulated Irregular Network, Kriging, Multilevel B-spline Approximation), two sink-filling algorithms (Planchon & Darboux; Wang & Liu), and two flow direction models (D8, D-infinity). Performance was first assessed using pixel-based Intersection over Union (IoU) metrics to quantify inter-method consensus. Independent plausibility-based validation was then conducted using near-contemporaneous Sentinel-2 imagery. Although pairwise statistical analysis identified workflows that achieved high inter-method consensus (median IoU = 0.90), external validation demonstrated that the CSF-MBA-Planchon-D8 workflow provided the most realistic presentation of optically observable channel corridors (validation IoU ≈ 0.85). These findings reveal that high inter-method agreement does not necessarily imply accurate landscape representation; multiple workflows may converge on systematically biased solutions. Ground filtering exerted the strongest influence on pairwise consensus, whereas plausibility-based validation highlighted the importance of selecting workflow combinations that preserve subtle channel morphology. Sink-filling and flow direction choices exerted comparatively minor effects in this low-gradient setting. The proposed dual-validation framework provides methodological guidance for wetland restoration planning and highlights the necessity of external validation in LiDAR-derived hydrological feature extraction. Full article

Background/Objectives: Habitat degradation and fragmentation reduce population size, genetic diversity, and connectivity, increasing extinction risk in small and isolated populations. Coastal wetlands of northwestern Peru have undergone extensive anthropogenic modification, yet the genetic and ecological status of resident carnivore populations remains poorly documented. This study aimed to assess genetic diversity, relatedness, demographic signals, and diet composition of a Pampas cat (Leopardus garleppi) population inhabiting the Mangroves San Pedro de Vice (MSPV), a Ramsar-listed coastal wetland. Methods: We combined noninvasive fecal genotyping using eight nuclear microsatellite loci with vertebrate DNA metabarcoding. Scat samples were collected across three field seasons (2019–2021). Individual identification, genetic diversity metrics, genetic mark–recapture estimation of census size (Nc), effective population size (Ne), bottleneck tests, and relatedness analyses were performed to evaluate population status and kin structure. Dietary composition was characterized using metabarcoding and assessed for sex-specific differences. Results: Sixty-eight scats yielded multilocus genotypes for nine individuals (six males, three females). Genetic analyses revealed moderate diversity (mean allelic richness = 3.47; observed heterozygosity = 0.69; expected heterozygosity = 0.58) and evidence consistent with a recent genetic bottleneck. Genetic mark–recapture analyses estimated a small census size (Nc = 9; 95% CI: 7.0–9.0), while the effective population size was markedly low (Ne = 2.4; 95% CI: 1.5–7.4), yielding an Ne/Nc ratio of ~0.27. Multiple first-order kin dyads were detected, indicating strong local kin structure and limited external recruitment. Metabarcoding identified eight vertebrate prey species, with diet dominated by the native rodent Aegialomys xanthaeolus. No significant sex-specific differences in diet composition were detected. Conclusions: The MSPV Pampas cat population represents a small, kin-structured range-edge population showing signatures consistent with recent genetic erosion and restricted connectivity. These patterns align with isolation in a degraded coastal wetland landscape, highlighting the importance of habitat protection, prey resource conservation, and restoration of functional connectivity to support long-term population persistence. Full article

This study evaluates the costs and benefits of participatory forest management (PFM) versus non-participatory forest management based on the perceptions and involvement of local communities in the Kilombero Valley Ramsar site, Tanzania. The area hosts ecologically significant wetlands managed through different regimes: forests managed by local communities under PFM and protected areas controlled by national authorities. Using data collected through focus groups, key interviews, household surveys, and direct observations in two villages—Siginali (PFM) and Kilama (non-participatory)—this research explores perceptions of two different forest management approaches. The results revealed: (i) a generally low awareness and participation in forest management activities in both villages; (ii) restrictions on forest resource access, essential for local livelihoods, were common and often poorly accepted in the two villages; (iii) neither approach alleviates poverty, instead, strict regulations have worsened livelihoods by eliminating traditional income sources; (iv) forced participation in patrols and fire control was also noted as an unfair burden without direct compensation; and (v) the “fortress” model is perceived as more effective at improving forest health and stopping illegal activity due to stricter patrols. The study concludes that while PFM supports forest sustainability, it needs enhanced local engagement, benefit-sharing mechanisms, and complementary income-generating initiatives such as ecotourism to sustainably balance conservation and community welfare. Full article

The longest-standing international treaty for wetland and waterbird protection, the Ramsar Convention has resulted in the establishment of more than 2500 protected areas covering over 2.5 million square kilometers around the world. However, its measures are not legally binding, and its effectiveness as a tool for wildlife conservation has rarely been quantitatively assessed. In Benin, West Africa, breeding waterbirds are subjected to intense hunting and egg harvesting for both commercial and subsistence purposes. We quantified count data of waterbirds and eggs taken by local hunters and trappers to assess the effectiveness of the Ramsar Convention as a wildlife conservation tool in southeastern Benin. During the six-month period between May and October 2022, 64 people reported harvesting a total of 12,053 breeding waterbirds and 63,987 eggs, comprising eight species in three families in Ramsar site 1018. Birds most heavily targeted included Allen’s Gallinule (Porphyrio alleni), with 4187 breeding birds taken (~35% of all birds captured), and the White-faced Whistling Duck (Dendrocygna viduata), with 24,491 eggs taken (~38% of all eggs taken) over the course of a single breeding season. The Eurasian Moorhen (Gallinula chloropus) and Lesser Moorhen (Paragallinula angulata) were the third and fourth most targeted bird species, respectively, followed by the African Swamphen (Porphyrio madagascariensis), Black Crake (Zapornia flavirostra), African Jacana (Actophilornis africanus), and African Crake (Cecropsis egregia). Captured waterbirds were sold live at local markets, while eggs were eaten by hunters, except eggs containing chicks, which were discarded. Our findings show heavy persecution of waterbirds during their breeding season, when nesting birds are especially vulnerable to human predation, on a scale that is likely unprecedented and threatens to drive declines of targeted species in Benin. As local residents do not currently appear to recognize any deterrents to the uncontrolled hunting of breeding waterbirds or the collection of eggs in Ramsar site 1018, there is an urgent need to better leverage the Ramsar Convention to enforce conservation practices in this region. Full article