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1.
Am J Primatol ; : e23631, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698704

RESUMO

The banded langur (Presbytis femoralis) is a critically endangered primate, restricted to Johor, Malaysia, with an estimated population size of less than 500 individuals. Traditionally, distribution studies on this highly threatened primate have relied on conventional methods such as DNA identification, live counting, and camera trapping. However, ethnoprimatology offers an alternative approach to data collection, involving the active participation of indigenous and local communities possessing valuable knowledge and experience with local primate species. This study employed an integrated approach incorporating ethnoprimatology by utilizing pooled local expert opinion, local surveys, interviews, and fecal DNA analysis, resulting in a novel distribution range for the banded langur. The combination of expert opinions revealed this species' most optimistic distribution scenario across Johor and Pahang, inhabiting various ecosystems, including lowland forests, peat swamps, and human-modified landscapes. Further interviews and surveys conducted within the Orang Asli community in Tasik Chini and Tasek Bera have provided additional support for the revised distribution, documenting occurrences of banded langur utilization in indigenous practices, such as food consumption, cultural beliefs, medicinal applications, and craftsmanship. Phylogenetic analysis demonstrated genetic differentiation between populations in Johor and Pahang, with the populations in the southern part of Peninsular Malaysia likely serving as ancestral sources for other populations. Consequently, this study not only elucidated the updated distribution of banded langur through DNA records and direct observations but also established the efficacy of ethnoprimatology as a precursory tool for uncovering the present distribution patterns of other primate species in Malaysia.

2.
Conserv Biol ; : e14288, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38757477

RESUMO

Sea-level rise (SLR) is expected to cause major changes to coastal wetlands, which are among the world's most vulnerable ecosystems and are critical for nonbreeding waterbirds. Because strategies for adaptation to SLR, such as nature-based solutions and designation of protected areas, can locally reduce the negative effects of coastal flooding under SLR on coastal wetlands, it is crucial to prioritize adaptation efforts, especially for wetlands of international importance for biodiversity. We assessed the exposure of coastal wetlands important for nonbreeding waterbirds to projected SLR along the Mediterranean coasts of 8 countries by modeling future coastal flooding under 7 scenarios of SLR by 2100 (from 44- to 161-cm rise) with a static inundation approach. Exposure to coastal flooding under future SLR was assessed for 938 Mediterranean coastal sites (≤30 km from the coastline) where 145 species of nonbreeding birds were monitored as part of the International Waterbird Census and for which the monitoring area was delineated by a polygon (64.3% of the coastal sites monitored in the Mediterranean region). Thirty-four percent of sites were threatened by future SLR, even under the most optimistic scenarios. Protected study sites and study sites of international importance for waterbirds were, respectively, 1.5 and 2 times more exposed to SLR than the other sites under the most optimistic scenario. Accordingly, we advocate for the development of a prioritization scheme to be applied to these wetlands for the implementation of strategies for adaptation to SLR to anticipate the effects of coastal flooding. Our study provides major guidance for conservation planning under global change in several countries of the Mediterranean region.


Exposición de los humedales de importancia para las aves acuáticas no reproductoras al incremento del nivel del mar en el Mediterráneo Resumen Se espera que el incremento en el nivel del mar (INM) cause cambios importantes en los humedales costeros, los cuales se encuentran entre los ecosistemas más vulnerables y son críticos para las aves acuáticas no reproductoras. Es crucial la priorización de los esfuerzos de adaptación, especialmente en los humedales con importancia internacional para la biodiversidad, ya que las estrategias de adaptación ante el INM, como las soluciones basadas en la naturaleza y la designación de áreas protegidas, pueden reducir localmente los efectos negativos de las inundaciones costeras por INM en los humedales costeros. Evaluamos la exposición de los humedales costeros con importancia para las aves acuáticas no reproductoras ante el INM proyectado en las costas del Mediterráneo en ocho países con un modelo de inundaciones costeras en el futuro bajo siete escenarios de INM para el año 2100 (de 44 a 161 cm) con un enfoque de inundación estática. Evaluamos la exposición a las inundaciones costeras bajo el INM futuro en 938 sitios costeros del Mediterráneo (≤ 30 km a partir de la costa), en donde monitoreamos a 145 especies de aves no reproductoras como parte del Censo Internacional de Aves Acuáticas y para los cuales el área de monitoreo estuvo delineada con un polígono (64.3% de los sitios costeros monitoreados en la región Mediterránea). El 34% de los sitios se vio amenazado por el INM en el futuro, incluso con los escenarios más optimistas. Los sitios de estudio protegidos y los sitios de estudio de importancia internacional para las aves acuáticas estuvieron expuestos 1.5 y 2 veces más al INM que otros sitios con el escenario más optimista. De acuerdo con esto, abogamos por el desarrollo de un esquema de priorización para aplicarse en estos humedales para la implementación de estrategias de adaptación al INM para anticipar los efectos de las inundaciones costeras. Nuestro estudio proporciona información importante para la planeación de la conservación bajo el cambio global en varios de los países del Mediterráneo.

3.
Sci Total Environ ; 932: 173078, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38723968

RESUMO

Coastal wetland ecosystems make an important contribution to the global carbon pool, yet their extent is declining due to aquaculture-related land use changes. We conducted an extensive investigation into the carbon stock and area coverage of macrophytes in a tropical coastal Ramsar wetland, Kolleru in Andhra Pradesh, India. A total of 72 quadrats of size 1 × 1 m2 were laid in the wetland, 19 species of macrophytes were collected and analyzed for carbon content using a CNHS analyzer. To assess changes in the wetland macrophytes, Normalized Difference Vegetation Index (NDVI) was estimated using Landsat time series data from 1975 to 2023. The importance value index (IVI) of macrophytes scored highest for the Ipomoea aquatica (41.4) and the lowest for Ottelia alismoides (1.9). Non-metric multidimensional scaling (NMDS) significantly (r = 0.1905, p = 0.0361) revealed a clear separation of macrophytes in ordination space. ANOVA indicated highly significant (p < 0.0001) variations in the carbon content of aboveground and belowground components of macrophytes. Among the different macrophytes, the highest carbon content was found in Phragmites karka (0.6 g. g-1) and the lowest was recorded in Utricularia stellaris (0.2 g. g-1). On an average, emergents in the Kolleru wetland sequester 1525 ± 181 g C m-2 yr-1, rooted floating species sequester 858 ± 101 g C m-2 yr-1, submerged macrophytes sequester 480 ± 60 g C m-2 yr-1, and free-floating macrophytes sequester 221 ± 90 g C m-2 yr-1. Land cover mapping revealed a decrease in spread of aquatic vegetation from 225.2 km2 in 1975 to 100.6 km2 in 2023. Although macrophytes are vital carbon sinks, the wetland conversion into fishponds has resulted in a loss of 55.3 % of carbon storage. Therefore, immediate restoration of macrophyte cover is vital for the proper functioning of carbon sequestration and mitigation of climate change impacts.


Assuntos
Sequestro de Carbono , Carbono , Áreas Alagadas , Índia , Carbono/análise , Monitoramento Ambiental
4.
Environ Monit Assess ; 196(5): 432, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38581451

RESUMO

The East Kolkata Wetlands (EKWT), designated as a Ramsar Site for its crucial role in sewage water purification, agriculture and pisciculture, faces escalating environmental threats due to rapid urbanisation. Employing the pressure-state-response (PSR) framework and Environmental Risk Assessment (ERA), this study spans three decades to elucidate the evolving dynamics of EKWT. Using Landsat TM and OLI images from 1991, 2001, 2011 and 2021, the research identifies key parameters within the PSR framework. Principal component analysis generates environmental risk maps, revealing a 46% increase in urbanisation, leading to reduced vegetation cover and altered land surface conditions. The spatial analysis, utilizing Getis-Ord Gi* statistics, pinpoints risk hotspots and coldspots in the EKWT region. Correlation analysis underscores a robust relationship between urbanisation, climatic response and environmental risk. Decadal ERA exposes a noteworthy surge in high-risk areas, indicating a deteriorating trend. Quantitative assessments pinpoint environmental risk hotspots, emphasizing the imperative for targeted conservation measures. The study establishes a direct correlation between environmental risk and air quality, underscoring the broader implications of EKWT's degradation. While acknowledging the East Kolkata administration's efforts, the research recognises its limitations and advocates a holistic, multidisciplinary approach for future investigations. Recommendations encompass the establishment of effective institutions, real-time monitoring, public engagement and robust anti-pollution measures. In offering quantitative insights, this study provides an evidence-based foundation for conservation strategies and sustainable management practices essential to safeguard the East Kolkata Wetlands.


Assuntos
Purificação da Água , Áreas Alagadas , Monitoramento Ambiental/métodos , Agricultura , Esgotos , Purificação da Água/métodos
5.
Environ Sci Pollut Res Int ; 31(19): 28549-28563, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38561533

RESUMO

Floodplain pans are hydrologically dynamic in nature and characterised by variables such as chlorophyll-a (chl-a), water, and sediment chemistry over their hydroperiods. The present study investigated the spatio-temporal variations in water and sediment physico-chemical, and chlorophyll-a concentration characteristics of six floodplain pans found in the Ramsar declared Makuleke wetlands, Kruger National Park, South Africa. The water and sediment physico-chemical variable values were generally elevated during the high-water period, whereas chlorophyll-a concentrations varied across pans and hydroperiod. Benthic chl-a concentration significantly varied across pans with concentrations ranging from 161 to 1036.2 mg m2. The two-way ANOVA showed significant differences in benthic chl-a concentration among hydroperiods, and no significant differences were observed in pelagic chl-a across pans and hydroperiods. Generally, pelagic and benthic chl-a concentration increased as water and sediment chemistry variables increased. Furthermore, three sediment variables, i.e. pH, calcium, and magnesium, and water conductivity were found to be significant in structuring benthic chlorophyll-a dynamics in pans. However, none of the sediment and water variables had a significant effect on pelagic chl-a. Hydroperiod had a significant effect on influencing chl-a concentration, with high and low water level periods being characterised by low and high chl-a concentration, respectively. The n-MDS results showed strong overlaps in chl-a biomass among the Makuleke floodplain pans across hydroperiods. The increasing chl-a concentration in these floodplain pans due to potential bioturbation effects as a result of large mammals could potentially lead to eutrophication, which in turn could affect the system's primary productivity and aquatic biota. Therefore, it is important to establish a continuous monitoring programme on these pans to inform sound management decisions.


Assuntos
Clorofila A , Monitoramento Ambiental , Sedimentos Geológicos , Áreas Alagadas , Sedimentos Geológicos/química , África do Sul , Clorofila , Água/química
6.
J Environ Manage ; 358: 120928, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38652990

RESUMO

Microplastics are ubiquitous, and their widespread prevalence in the ecosphere has generated concerns about their potential effects on terrestrial and aquatic organisms. However, studies pertaining to ecologically sensitive freshwater ecosystems, such as Ramsar wetlands, is scarce. Therefore, the study was conducted in Loktak, the world's only floating lake, and one of the largest wetland in the Indian Himalayan region. The wetland's degradation and pollution have resulted its inclusion in the Montreux Record, underscoring the need for studying this eco-sensitive freshwater system. This work investigated the (i) abundance, morphotype and size of microplastics in fish, and (ii) chemical composition of the microplastics consumed and accumulated in the fish of Loktak lake. Fish samples representing eight species were collected and analyzed for microplastics. Results revealed that ∼91% of the sampled fish ingested microplastics. Fragment was identified as the predominant morphotype (∼82%). Plastic polymers including polyamide (PA), polystyrene (PS), polycarbonate (PC) and carboxymethyl cellulose (CMC) were detected. The occurrence of heavy metals - chlorine (Cl), palladium (Pd), sodium (Na), zinc (Zn), lead (Pb) and copper (Cu) suggests their adhesion on the microplastics. The occurrence of microplastics in fish indicates pollution in the lake and poses a potential health risks to humans through consumption. Therefore, implementing comprehensive management approaches is imperative to mitigate this emerging pollution and uphold the ecological integrity of the Ramsar site. Substantial information on microplastics and their potential human exposure through fish consumption, particularly in the Indian Himalayan region, remains to be assessed, underscoring the need for extensive study.


Assuntos
Monitoramento Ambiental , Peixes , Lagos , Microplásticos , Poluentes Químicos da Água , Áreas Alagadas , Animais , Microplásticos/análise , Poluentes Químicos da Água/análise , Índia , Metais Pesados/análise , Plásticos/análise
7.
Environ Sci Pollut Res Int ; 31(17): 25671-25687, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38483715

RESUMO

This study documents the socio-economic baselines in selected oil-impacted communities prior to the commencement of the Ogoni clean-up and restoration project. Adopting mixed approach consisting of semi-structured interviews, focus group discussions (FGDs), key informant interviews (KIIs), and household surveys, we surveyed the pre-remediation socio-economic conditions in the Ogoniland communities between July 2018 and March 2019. Results indicated that almost all respondents (99.6%) agreed that the smell of petroleum products or crude oil was evident in the air they breathed even as there were visible black particles (soot) in the respondents' nostrils, on their clothes, and in water. The respondents described the ambient air as smoky and choked with an offensive smell. The household waters were smelly, brownish, or oily, and most respondents (76%) cannot afford to treat their water. Forty-two percent of the respondents who relied on fishing and farming for a living sought for alternative means of subsistence and acknowledged that oil pollution caused stunted growth and low crop yield. The majority of respondents (91%) reported falling fish catches, while the fish caught smell and taste of oil, lowering their market value and posing a potential health risk to consumers. It is evident that oil pollution has impacted the socio-ecological values and sustainable livelihood in Ogoniland. This study provides baseline data for monitoring post-remediation socio-economic improvements in Ogoniland. It also highlights areas of urgent intervention to improve livelihood, and access to basic amenities (e.g., potable drinking water), waste management infrastructure, and statutory policy changes for sustainable development in Ogoniland.


Assuntos
Poluição por Petróleo , Petróleo , Animais , Nigéria , Níger , Poluição por Petróleo/análise , Fatores Socioeconômicos , Água
8.
Environ Sci Pollut Res Int ; 30(54): 115246-115265, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37880398

RESUMO

Uluabat Lake holds a significant status as one of our country's essential Ramsar areas. Nevertheless, the lake faces considerable pressure from environmental pollutants. This study employed GIS-based index methods to examine the heavy metal pollution and water quality in Uluabat Lake. To achieve this, sediment and water samples were collected from 19 different locations during various seasons. The concentrations of As, Ni, Cr, Zn, Cu, Cd, Pb, Hg, Al, Fe, and Mn in these samples were analyzed. The average contents of the investigated heavy metals in the lake waters were found to be in the following order: Al > Fe > Mn > As > Zn > Ni > Pb > Cu > Cr > Hg > Cd. The As content in the lake waters exceeded the limit value of 10 µg/L, as defined by TS-266 (2005) and WHO (2017) guidelines. Consequently, the lake waters were deemed unsuitable for drinking. The health risk assessments revealed that consuming the lake waters could lead to both carcinogenic and non-carcinogenic health problems. However, all other metal concentrations were measured below the specified limit values. Based on index calculations, the heavy metal pollution index value indicated that the lake water samples were suitable for drinking water use. Additionally, all samples fell into the "low pollution" category according to the heavy metal evaluation index, and degree of contamination values. However, geoaccumulation index values indicated that As was moderately contaminated. Moreover, enrichment factors of As, Cr, Ni, Pb, and Cd exhibited significant enrichment in lake sediments, with pollution load index values of all sediment samples indicating the impact of anthropogenic pollutants and a decline in sediment quality. Considering all the obtained results together, it can be concluded that environmental pollutants, especially heavy metal pollution, primarily enter the lake water through stream transports, leading to pollution in Uluabat Lake.


Assuntos
Poluentes Ambientais , Mercúrio , Metais Pesados , Poluentes Químicos da Água , Lagos , Cádmio , Turquia , Chumbo , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Sedimentos Geológicos , Metais Pesados/análise , Qualidade da Água , Medição de Risco , China
9.
Environ Sci Pollut Res Int ; 30(55): 117729-117747, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37872337

RESUMO

Monitoring the water levels and volume changes of lakes and reservoirs enables us to understand the importance of better protection and managing water resources in an ecologically optimum manner. Although some lakes, such as Burdur Lake, are not a source of drinking water, they are home to many endangered animals, endemic plants, and some species. Therefore, monitoring the changes in these lakes over time is important for various reasons. While water level measurement stations in lakes and wetlands provide important information, it may not always be possible to obtain this data. In this study, we investigated the long-term changes in Burdur Lake, a Ramsar site, by integrating the Digital Elevation Model (DEM) obtained by the unmanned aerial vehicle (UAV) with shoreline information obtained from the Landsat mission. This study aimed to investigate the usability, advantages, and disadvantages of the UAV-Landsat integration for volume calculation. As a result, we successfully determined the water level as r= 0.999 and the cumulative volume loss at a rate of 97.5%. Burdur Lake experienced a significant reduction in its area decreasing from 206 to 120 km2 (42%) between 1984 and 2022. Furthermore, the water volume of the lake decreased by 2.70 km3 over a span of 38 years. This study demonstrates the potential and limitations of the presented UAV-remote sensing integration. Our proposed method is beneficial for determining short and long-term water levels and volumetric changes with high accuracy.


Assuntos
Monitoramento Ambiental , Lagos , Monitoramento Ambiental/métodos , Dispositivos Aéreos não Tripulados , Imagens de Satélites , Água
10.
Environ Monit Assess ; 195(10): 1194, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37698676

RESUMO

Wetland ecosystems provide critical ecological services to both humans and wildlife. However, many wetlands around the world are facing challenges that threaten their ecological integrity and jeopardize their status as Ramsar Convention sites. The Shadegan Wetland, a Ramsar site since 1975, has been on the Montreux Record since 1993 due to changing conditions in the wetland. This study aims to utilize linear programming (LP) techniques to evaluate the status of criterion IV of the Ramsar Convention within the Shadegan Wetland. Using mathematical language and Excel software, we defined criterion IV and developed a linear model. The Lingo software was employed to verify the model by setting constraints for proxy variables (X variables). We selected constraints based on extreme climatic conditions, such as energy and water limitations, during the study period while considering the trend of each variable. By identifying effective interventions for promoting sustainable use of the wetland while preserving its ecological balance, the LP can support the efforts to re-nominate the Shadegan Wetland as a Ramsar site. Considering the critical conditions, the lowest value of Z in the studied period unravels the critical year as the target. Based on the result, 2015 with the lowest value of the Z index (- 0.36) was identified as the critical year in the entire study period starting from 2001-2019. In the critical year itself, the population of birds equals 50,000 birds, while the average population of birds over the course of the past 20 years was nearly 37,000 birds.


Assuntos
Ecossistema , Áreas Alagadas , Humanos , Programação Linear , Monitoramento Ambiental , Ásia
11.
Environ Monit Assess ; 195(10): 1232, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37728656

RESUMO

MP contamination in the gastrointestinal tract (GIT) of Prussian carp (Carassius gibelio) used in fishmeal production was examined. The samples were collected from Balik Lake, Karabogaz Lake, and Liman Lake located in Kizilirmak Delta, Türkiye. The overall average abundance was 3.20±0.18 MP per fish and 0.036±0.002 MP per g. No significant correlation was determined between the MP abundance in the fish, fish length, and fish weight. The polymers were composed of 56.91% PET, 25.20% PP, 9.76% PE, and 8.13% PA. The determined shapes were fiber (78.0%), fragment (13.46%), and film (8.54%). The size ranged between 112 and 4775 µm with an average of 1341.41±66.07 µm. Depending on the occurrence frequency and abundance, it can be concluded that Carassius gibelio can be considered a MP vector in fishmeal. The results provide an essential baseline for future MP studies on the potential effects of MPs on aquatic organisms, fate, and impact on the fishmeal production process, aquaculture practices, and human health.


Assuntos
Carpas , Cyprinidae , Animais , Humanos , Microplásticos , Plásticos , Monitoramento Ambiental , Ingestão de Alimentos
12.
Environ Sci Pollut Res Int ; 30(30): 76122-76142, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37233936

RESUMO

As a part of the monitoring practice of the lone natural habitat of the endemic and endangered Rucervus eldii eldii McClelland or Sangai, the paper reports sediment and water characteristics of Keibul Lamjao National Park-the only floating national park of the world in Manipur, Indo Burma hotspot. The water analysis showed low pH (5.69 ± 0.16), high electrical conductivity (342 ± 13.01 µS m-1), high turbidity (33.2 ± 9.407 NTU), and high phosphate concentrations (0.92 ± 0.11 mg L-1) during the study period. The water quality index values calculated indicate that the park water during post-monsoon season is unfit for drinking. Thus, the degrading water quality poses a serious risk to the health of the deer and other species in the park. At present, Sangai in its natural habitat is threatened by pollution, encroachment, phoomdi thickness reduction, and inbreeding depression. To address the problem of inbreeding, Pumlen pat is considered as a second suitable natural habitat for the deer reintroduction program. During the study, water characteristics of the wetland showed similar characteristics as KLNP, i.e., low pH (5.86 ± 0.30), high electrical conductivity (377.6 ± 5.55 µS m-1), high turbidity (32.36 ± 4.91 NTU), and high phosphate concentrations (0.79 ± 0.14 mg L-1). Likewise, sediments showed high TP accumulation that ranged from 197.03 ± 0.75 to 332.88 ± 0.99 mg kg-1 for KLNP and 245.18 ± 0.85 to 351.48 ± 0.71 mg kg-1 for Pumlen pat, respectively. Both, the lone natural habitat and the proposed habitat showed deteriorating water quality. As such, continuous monitoring of KLNP and Pumlen pat water and sediment quality should be a priority during the management practices to protect the endangered deer and health of the habitats for long-term conservation.


Assuntos
Cervos , Qualidade da Água , Animais , Mianmar , Parques Recreativos , Índia , Ecossistema , Fosfatos , Conservação dos Recursos Naturais
13.
Sci Bull (Beijing) ; 68(12): 1306-1316, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37217429

RESUMO

Mangrove forests deliver incredible ecosystem goods and services and are enormously relevant to sustainable living. An accurate assessment of the global status of mangrove forests warrants the necessity of datasets with sufficient information on spatial distributions and patch patterns. However, existing datasets were mostly derived from âˆ¼30 m resolution satellite imagery and used pixel-based image classification methods, which lacked spatial details and reasonable geo-information. Here, based on Sentinel-2 imagery, we created a global mangrove forest dataset at 10-m resolution, namely, High-resolution Global Mangrove Forests (HGMF_2020), using object-based image analysis and random forest classification. We then analyzed the status of global mangrove forests from the perspectives of conservation, threats, and resistance to ocean disasters. We concluded the following: (1) globally, there were 145,068 km2 mangrove forests in 2020, among which Asia contained the largest coverage (39.2%); at the country level, Indonesia had the largest amount of mangrove forests, followed by Brazil and Australia. (2) Mangrove forests in South Asia were estimated to be in the better status due to the higher proportion of conservation and larger individual patch size; in contrast, mangrove forests in East and Southeast Asia were facing intensive threats. (3) Nearly, 99% of mangrove forest areas had a patch width greater than 100 m, suggesting that nearly all mangrove forests were efficient in reducing coastal wave energy and impacts. This study reports an innovative and up-to-date dataset and comprehensive information on mangrove forests status to contribute to related research and policy implementation, especially for supporting sustainable development.

14.
Environ Monit Assess ; 195(5): 573, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37060391

RESUMO

Wetland bacterial communities are highly sensitive to altered hydrology and the associated change in water physicochemical and biological properties leading to shifts in community composition and diversity, hence affecting the ecological roles. However, relevant studies are lacking in the wetlands of central Himalayas Nepal. Thus, we aimed to explore the variation of bacterial communities, diversity, and ecologic functions in the wet and dry periods of a wetland (designed as Ramsar site, Ramsar no 2257) by using 16S rRNA gene-based Illumina MiSeq sequencing. We reported a pronounced variation in water physicochemical and biological properties (temperature, pH, Chla, DOC, and TN), bacterial diversity, and community composition. Bacterial communities in the dry season harbored significantly higher alpha diversity, while significantly higher richness and abundance were reflected in the wet season. Our results uncovered the effect of nutrients on bacterial abundance, richness, and community composition. Fourteen percent of the total OTUs were shared in two hydrological periods, and the largest portion of unique OTUs (58%) was observed in the dry season. Planctomycetes and Bacteroidetes dominated the wet season exclusive OTUs; meanwhile, Actinobacteria dominated the dry season exclusive OTUs. Bacteria in these wetlands exhibited divergent ecological functions during the dry and wet seasons. By disclosing the variation of water bacterial communities in different hydrologic periods and their relationship with environmental factors, this first-hand work in the Ramsar site of Nepal will develop a baseline dataset for the scientific community that will assist in understanding the wetland's microbial ecology and biogeography.


Assuntos
Bactérias , Monitoramento Ambiental , RNA Ribossômico 16S/genética , Nepal , Bactérias/genética , Áreas Alagadas , Água
15.
Artigo em Inglês | MEDLINE | ID: mdl-36942452

RESUMO

Wetlands provide unique habitat functions that benefit society by provisioning food, recreation, and ecosystem sustainability. Warfare affects the habitats of wetland-dependent reptiles, amphibians, and birds in both positive and negative ways, and opportunities exist to improve the management of wildlife habitat using a warfare ecology framework. Recent events in Ukraine highlight these relationships and provide stimulus to further consider the implications of current events for natural resources. In response, this commentary highlights both degradational and positive impacts of warfare on wetland fauna during the cyclical preparation, active conflict, and recovery phases. For example, the active conflict phase often initiates ecological disturbance regimes that couple large-scale landscape alteration with the release of chemicals and other materials into wetlands, leading to reduced reproductive potential and population declines in wetland-dependent species (e.g., amphibians, waterfowl) along with decreased overall wetland biodiversity and habitat quality. In contrast, wetland-dependent wildlife can benefit from (1) conservation activities occurring on military installations maintained to support training activities and (2) restoration efforts initiated after the cessation of combat. For example, many threatened and endangered reptiles and amphibians find refugia on military lands in the USA and internationally, and international protections for wetland resources (including the Ramsar Convention) have been established to promote their sustainability and wise use. Additional research is needed to improve the protection of valuable wetland resources by further enhancing ongoing conservation and planning efforts and improving strategies to mitigate the negative impacts of warfare on wetland dependent species throughout each phase of the warfare ecology cycle. Integr Environ Assess Manag 2023;00:1-9. Published 2023. This article is a US Government work and is in the public domain in the USA. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

16.
J Environ Manage ; 334: 117401, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36774899

RESUMO

A first hand study on guild structure of fish species (n = 148) in Ashtamudi Estuary, a Ramsar Site of International importance, was carried out from May 2019 to April 2020 based on temporal (monsoon, pre-monsoon and post-monsoon seasons) and spatial (upper, middle and lower zones) data. Guild composition consisted of eight estuarine use guilds (marine estuarine opportunist, marine estuarine dependent, estuarine resident species, anadromous species, freshwater migrants, freshwater stragglers, catadromous and marine stragglers) and eight feeding guilds (zooplanktivore, zoobenthivore, carnivores, herbivores, invertebrate feeders, omnivores, detritus feeders and piscivores). The most dominant estuarine use guilds comprised of marine migrants (marine estuarine opportunist and marine estuarine dependent), whereas carnivore, omnivore and zooplanktivore formed the dominant feeding guilds in Ashtamudi Estuary. The species diversity decreased from upper to lower zone and was highest during the post-monsoon period. The present study has seen a decrease in estuarine resident and freshwater species due to reduced freshwater inflow, saltwater intrusion, unsustainable fishing and inadequate environmental management practices. Hence, we propose a management framework to improve the ecosystem of Ashtamudi Estuary with a special focus on its fish species and their estuarine use.


Assuntos
Ecossistema , Estuários , Animais , Água Doce , Índia , Estações do Ano , Peixes
17.
Environ Sci Pollut Res Int ; 30(18): 51955-51976, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36820971

RESUMO

The wetland stagnation is the premise of the wetland depth (WD) but is lacking in detail. The research looks into the correlation of stagnant wetland's depth and their ecological status in the Central Tamil Nadu District (CTND) because of few studies. Seventy-five chosen stagnant wetlands are hydrologically isolated; depths were categorized into less than 5 ft., 6 to 10 and above 10 ft., surveyed by the range of methods from districts such as Karur (KD), Namakkal (ND) and Tiruchirappalli (TD). The human disturbance score (HDS) is categorized as least impacted (0-33), moderately impacted (33-67) and highly impacted (67-100). The impacts of land use and land cover (LULC) changes over 9 years (2010-2019) through the maximum likelihood method. Overall, 54% of wetland depths (WD) were less than 5 ft.; 25.6% were 6-10 ft. and 20.2% were 100 ft. District-wise, wetland degradation was the utmost in the TD, followed by ND and KD. Except in KD, the remaining district wetlands were of MI category with diverse HDS. The correlation test revealed a positive relationship between WD against the alteration of the buffer zone, habitat, hydrology and HDS. However, it is a negative relationship between landscape alteration and wetland pollution. The impacts of land use and land cover (LULC) changes confirm that severe decline in wetlands habitat and water bodies' area is due to built-up area, cultivated land expansion and increasing population. Our study provided evidence that the WD is connected to wetland conditions that have a quantitative influence, and the ramifications of the findings were examined in the context of local development planning. Additional research will be needed due to limited surveyed wetlands with similar geographical locations.


Assuntos
Monitoramento Ambiental , Áreas Alagadas , Humanos , Índia , Monitoramento Ambiental/métodos , Ecossistema , Conservação dos Recursos Naturais
18.
Mar Pollut Bull ; 188: 114618, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36682305

RESUMO

An attempt has been adopted to predict the As and NO3- concentration in groundwater (GW) in fast-growing coastal Ramsar region in eastern India. This study is focused to evaluate the As and NO3- vulnerable areas of coastal belts of the Indo-Bangladesh Ramsar site a hydro-geostrategic region of the world by using advanced ensemble ML techniques including NB-RF, NB-SVM and NB-Bagging. A total of 199 samples were collected from the entire study area for utilizing the 12 GWQ conditioning factors. The predicted results are certified that NB-Bagging the most suitable and preferable model in this current research. The vulnerability of As and NO3- concentration shows that most of the areas are highly vulnerable to As and low to moderately vulnerable to NO3. The reliable findings of this present study will help the management authorities and policymakers in taking preventive measures in reducing the vulnerability of water resources and corresponding health risks.


Assuntos
Arsênio , Água Subterrânea , Poluentes Químicos da Água , Nitratos/análise , Arsênio/análise , Bangladesh , Poluentes Químicos da Água/análise , Monitoramento Ambiental
19.
Environ Sci Pollut Res Int ; 30(1): 78-89, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36376646

RESUMO

Saline lakes are internationally known for unique chemical compositions, incorporate assorted foliage, and give a few biological system benefits and have high environmental, financial, and social qualities are additionally assigned as the Ramsar site for giving wetlands to migratory birds. The anthropogenic and regular unsettling influences have influenced the water nature of these lakes by immediate or circuitous tainting of various contaminations in releases from refining, mining, and modern locales. The impacts of such exercises bring about changes to the typical attributes of saline lakes, principal limnological changes, and loss of biodiversity that debase the upsides of saline lakes. Saline water bodies are not expected and are perceived as significant inland sea-going environments. To review the present circumstance, there is a need to bring issues to light of the idea of dangers and their effects on the environment. The article remembers the situation with water contamination for some saline lakes and its unfavorable impact on biodiversity. The audit plans to cause notice the broad harm of saline lakes that have now gone through because of contamination from last years.


Assuntos
Monitoramento Ambiental , Lagos , Lagos/química , Áreas Alagadas , Biodiversidade
20.
Heliyon ; 8(11): e11875, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36468112

RESUMO

Tanguar Haor (TH), an ecologically critical area (ECA) and a Ramsar site of worldwide significance, is an essential wetland ecosystem for the Bangladesh's economic, ecological, social, and cultural aspects. Fish, aquatic plants, amphibians, reptiles, birds, and mammals are notable among the floral and faunal compositions found in this haor. Unfortunately, unsustainable exploitation of its natural resources poses a serious threat to the TH ecosystem. Therefore, the broad objective of this study was to review the status of fish biodiversity along with the driving factors of biodiversity loss and the management issues of the TH ecosystem. A total of 143 species of fishes (137 indigenous and 6 exotic) under 35 families, and 12 orders were documented during the last two decades. Species diversity of the haor has been changed over time due to the effects of climatic, anthropogenic, socioeconomic, and policy related drivers. Furthermore, high dependency on fisheries resources, poverty, and the lack of empowerment to manage the TH fishery were responsible for fish diversity decline. Therefore, ecosystem based co-management through active participation of local community, establishment of balanced fishing tactics, and strengthening alternative livelihoods for highly depended poor harvesters are strongly recommended for the proper management of this valued wetland ecosystem. Furthermore, this review proposes immediate and useful conservation initiatives for the studied wetlands, including comprehensive stock assessment, establishment of gene banks and fish sanctuaries, a combination of input and output control, and regulation with the ECA and RAMSAR guidelines.

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