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1.
Sci Total Environ ; 932: 173078, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38723968

ABSTRACT

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.


Subject(s)
Carbon Sequestration , Carbon , Wetlands , India , Carbon/analysis , Environmental Monitoring
2.
Environ Monit Assess ; 195(11): 1386, 2023 Oct 27.
Article in English | MEDLINE | ID: mdl-37889333

ABSTRACT

It is becoming more widely recognised that free-ranging dogs, which have a nearly global distribution, threatening native wildlife. Their increasing population and spread to new areas is of growing concern for the long-term viability of wildlife species. Hence, it is imperative to understand the factors responsible for their infestation and map areas where native species are most vulnerable. Using the random forests algorithm, we modelled the free-ranging dog infestation in the Trans-Himalayan region to pinpoint the high-risk areas where free-ranging dogs are threatening the native wildlife species. We found that the likelihood of free-ranging dog occurrence is most in valley regions and up to 4000 m, often in proximity to roads. Our results also indicated that free-ranging dog prefers areas with wildlife near to protected areas. The predictor variables, such as potential evapotranspiration of the coldest quarter, distance to protected areas, elevation, distance to roads, and potential evapotranspiration of the driest quarter, significantly influence the distribution of the free-ranging dogs. We found that within the Ladakh region of the Trans-Himalayan area, the high-risk zones for free-ranging dogs are located in and around Hemis National Park, Karakoram Wildlife Sanctuary, and Changthang Wildlife Sanctuary. While, in the Lahaul and Spiti region the high-risk areas encompass Pin Valley National Park, Inderkilla National Park, Khirganga National Park, Kugti Wildlife Sanctuary, and several other protected areas. We identified the potentially high-risk areas for implementing strategies to mitigate the possible impact of free-ranging dogs on native wildlife of the Himalayas. Hence, the identified high priority areas can be used for implementing actions for controlling the population growth and further preventing the infestation of the free-ranging dogs into the new areas.


Subject(s)
Animals, Wild , Environmental Monitoring , Animals , Dogs , Environment , Parks, Recreational
3.
Biology (Basel) ; 12(6)2023 May 29.
Article in English | MEDLINE | ID: mdl-37372071

ABSTRACT

Insufficient research has been conducted on musk deer species across their distribution range, primarily because of their elusive behaviour and the fact they occupy remote high-altitude habitats in the Himalayas above 2500 m. The available distribution records, primarily derived from ecological studies with limited photographic and indirect evidence, fail to provide comprehensive information on the species distribution. Consequently, uncertainties arise when attempting to determine the presence of specific taxonomic units of musk deer in the Western Himalayas. This lack of knowledge hampers species-oriented conservation efforts, as there need to be more species-specific initiatives focused on monitoring, protecting, and combatting the illegal poaching of musk deer for their valuable musk pods. We used transect surveys (220 trails), camera traps (255 cameras), non-invasive DNA sampling (40 samples), and geospatial modelling (279 occurrence records) to resolve the taxonomic ambiguity, and identify the suitable habitat of musk deer (Moschus spp.) in Uttarkashi District of Uttarakhand and the Lahaul-Pangi landscape of Himachal Pradesh. All the captured images and DNA-based identification results confirmed the presence of only Kashmir musk deer (KDM) (Moschus cupreus) in Uttarakhand and Himachal Pradesh. The results suggest that KMD inhabit a narrow range of suitable habitats (6.9%) of the entire Western Himalayas. Since all evidence indicates that only KMD are present in the Western Himalayas, we suggest that the presence of other species of musk deer (Alpine musk deer and Himalayan musk deer) was wrongly reported. Therefore, future conservation plans and management strategies must focus only on KMD in the Western Himalayas.

4.
Environ Res ; 229: 115967, 2023 07 15.
Article in English | MEDLINE | ID: mdl-37086883

ABSTRACT

Wetland degradation through a diverse spectrum of anthropogenic stressors worldwide has taken a heavy toll on the health of wetlands. This study examined the health of a semi-urban wetland Bodsar, located in the Kashmir Himalaya using multicriteria analysis approach assimilating data on land use land cover (LULC), landscape fragmentation, soil loss, and demography. Wetland and catchment-scale land system changes from 1980 to 2022 were assessed using high-resolution imagery. Fragmentation of the natural landscape was assessed using the Landscape Fragmentation Tool (LFT) and soil loss was assessed using the Revised Universal Soil Loss Equation (RUSLE). In addition, the water quality was examined at 12 sites distributed across the wetland using standard methods. Satellite data revealed 12 categories of land use with areas under exposed rock, orchards, built-up and sparse forest having increased by 1005%, 623%, 274%, and 37% respectively. LFT indicated that the core (>500 acres) and core (<250 acres) zones decreased by approximately 16% and 64%, respectively, whereas the areas under the perforated, edge and patch classes increased significantly. RUSLE estimates show a ∼77% increase in soil erosion from 116.26 Mg a-1 in 1980 to 205.68 Mg a-1 in 2022, mostly due to changes in LULC. Total phosphorus (0.195-2.04 mg L -1), nitrate nitrogen (0.306-2.79 mg L -1), and total dissolved solids (543-774 mg L-1) indicated nutrient enrichment of the wetland influenced by anthropogenically-driven land system changes. The wetland degradation index revealed that 21% of the wetland experienced high-to-severe degradation, 62% experienced moderate degradation, and 17% did not face any significant degradation pressure. The novel GIS-based approach adopted in this study can act as a prototype for ascertaining the catchment-scale degradation of wetlands worldwide.


Subject(s)
Geographic Information Systems , Wetlands , Environmental Monitoring/methods , Soil , Forests , Conservation of Natural Resources
5.
Environ Sci Pollut Res Int ; 30(3): 7930-7941, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36048395

ABSTRACT

Coliform pollution for the last three decades in major river systems of the world has resulted in far ranging impacts on water quality. In this context, the present study aimed to assess the levels of indicator bacteria like total Coliform (TC), fecal Coliform (FC) and fecal Streptococcus (FS) in major watersheds of Kashmir valley. Sampling was carried out for a period of 2 years (summer 2017 to spring 2019) along several upstream, midstream and downstream reaches of Jhelum River Basin (JRB), while analysis was carried out by multiple tube fermentation technique involving Most Probable Number (MPN). Major highlights of the results revealed high levels of TC, FC and FS among downstream sites with pronounced seasonal variations between summer and winter. TC was highest at all the reaches and during all the seasons followed by FC and FS. Non-metric multidimensional scaling (NMDS) revealed more variation in Coliform count among reaches as compared to seasons. Mantle test revealed that environmental factors like observable environmental pressure (OEP) (r: 0.235, p < 0.0001), DO (r: 0.2815, p < 0.0001) and temperature (r: 0.04419, p = 0.0104) had prominent effect on Coliform distribution as compared to geographical factors. The study thus highlights the prevalence of Coliform bacteria along JRB resulting from fecal sources. Due to growing urbanization and lack of adequate sewage treatment facilities, there is an increase in the levels of Coliform bacteria along downstream reaches especially those residing within lower Jhelum and Dara watershed, which could jeopardize water quality and public health.


Subject(s)
Environmental Monitoring , Water Pollution , Water Pollution/analysis , Water Quality , Rivers/microbiology , Gram-Negative Bacteria , Feces/microbiology , Water Microbiology
6.
Sci Rep ; 12(1): 5817, 2022 04 06.
Article in English | MEDLINE | ID: mdl-35388114

ABSTRACT

With growing water scarcity, jeopardized by climate change, springs are likely to perform a vital role in meeting the domestic water demand in future. This paper examines the water quality status of Kashmir valley springs in relation to their geographical location, regional hydrogeological conditions, anthropogenic activities and climate change. We analyzed data for 258 springs from the whole Kashmir valley using water quality index (WQI) and geographic information system techniques. WQI ranged from 23 (excellent water) to 537 (water unsuitable for drinking). The WQI indicated that 39.5% of the springs had excellent waters, 47.7% had good water, 5% had poor water, 1.6% had very-poor water, and 6.2% of the springs had water unfit for drinking purposes. The Piper diagram identified Ca-Mg-HCO3, Ca-Mg-SO4, and Na-HCO3 as the most predominant hydro-chemical facies, whereas Gibbs diagram revealed that the water of springs in the study region is mainly controlled by rock weathering dominance. The results of the study offer inputs about the water quality to be used by the concerned departments and agencies at a bigger scale for drinking purposes. Our findings therefore suggest that springs which are in thousands in Kashmir landscape have the potential to offer viable solution to the rising drinking water demand and therefore merit an attention for their protection and management.


Subject(s)
Drinking Water , Groundwater , Water Pollutants, Chemical , Environmental Monitoring/methods , Fresh Water , Water Pollutants, Chemical/analysis , Water Quality
7.
Environ Monit Assess ; 193(11): 710, 2021 Oct 09.
Article in English | MEDLINE | ID: mdl-34626241

ABSTRACT

The knowledge on urban ecosystem dynamics is being increasingly felt due to unprecedented symptoms arising out of urbanization. This study is aimed to assess land use-land cover changes (LULCCs) around a wetland ecosystem using high spatial resolution CORONA and Google Basemap satellite imageries. The imageries were processed by digitizing land cover features at 1:3000 scale in ArcGIS 10.1. The imageries were classified into nine classes, and an estimation of accuracy was performed utilizing the Kappa coefficient and error matrices. The overall accuracy obtained was 94% for the 2017 dataset. The key findings indicated a loss of 23% in the wetland area from 1980 to 2017. While in the vicinity, a significant increase in green spaces (706.2%) and roads (89.4%) was observed. Morphometric analysis revealed that the wetland has lost a surface area of 10.2 ha from 1980 to 2017. The maximum length (Lmax) of the wetland was reduced by 722 m while the maximum width (Wmax) decreased by 78 m. Bathymetric analysis revealed that the wetland is shallow with a depth ranging from 10 to 174 cm. The Carlson's Trophic State Index (TSI) of wetland ranging from 74 to 87 indicates hyper-eutrophic waters. Overall, the loss of wetland area, together with the reduction in morphometric features, low depth, and higher trophic status speak of anthropogenic pressures that are compromising the ecological integrity of this wetland. Therefore, landscape planning and governance are of pivotal importance for the conservation and management of wetland ecosystems in this region.


Subject(s)
Ecosystem , Wetlands , Environmental Monitoring , Satellite Imagery , Urbanization
8.
Environ Monit Assess ; 192(2): 121, 2020 Jan 17.
Article in English | MEDLINE | ID: mdl-31953600

ABSTRACT

The lakes of Kashmir Valley show multiple signs of deterioration. This study integrated multiple datasets pertaining to the land system, lake bathymetry and water quality in GIS environment to limnologically characterize the Nigeen Lake. Settlements in the vicinity of the lake were mapped using high-resolution satellite data of 2003 and 2016. Lake depths measured at 235 points spread across the lake surface were used to produce the detailed bathymetry of Nigeen Lake. Surface water quality data at five sites pertaining to 22 physico-chemical parameters was analyzed for limnological characterization of the lake. The quality of lake water is within the permissible limits as per the drinking water standards set forth by World Health Organization (WHO); however, the values of secchi-disc transparency (0.52-1.39 m) and total phosphorous (184-687 µg L-1) indicate hypereutrophic state of the lake. The settlements in the lake vicinity expanded by 30% from 2003 to 2016. The bathymetry analysis revealed that the lake depth varied from 1.02 to 6.07 m. The reckless urbanization and inadequate sewage treatment system together with high residence time of water in the Nigeen Lake are responsible for enhanced nutrient enrichment and deterioration in water quality.


Subject(s)
Environmental Monitoring , Lakes/chemistry , Phosphorus/analysis , Urbanization , Water Quality/standards
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