Asian Journal of Environment & Ecology

Sea Snakes of India: A Review on Diversity, Ecology and Conservation

Rupal Dupare — 2026-05-20

Sea snakes (family Elapidae, subfamilies Hydrophiinae and Laticaudinae) constitute a remarkable evolutionary radiation of secondarily aquatic reptiles adapted to nearshore and pelagic marine environments across the Indo-Pacific Ocean. India, with its 7,516-kilometre coastline encompassing the Arabian Sea, Bay of Bengal, Lakshadweep Sea, and the territorial waters surrounding the Andaman and Nicobar Archipelago, supports approximately 26 species of sea snakes, making it one of the most significant sea snake bioregions in the world. Despite their ecological importance as mesopredators in tropical and subtropical marine food webs, Indian sea snakes remain insufficiently studied relative to their global significance. This review synthesises current knowledge on the systematics and taxonomy, biogeography, morphological and physiological adaptations, dietary ecology, reproductive biology, venom biochemistry, and conservation status of sea snakes occurring in Indian waters. A comprehensive literature survey spanning 2000–2026 was conducted across multiple academic databases, revealing persistent knowledge gaps in population ecology, molecular diversity, and long-term trend monitoring for Indian populations. The major documented threats include incidental capture in artisanal and industrial fisheries, coastal habitat degradation, coral reef bleaching driven by climate change, and marine pollution. Most Indian sea snake species are listed in Schedule I of the Wildlife (Protection) Act, 1972, affording them substantial legal protection, but enforcement in the marine context remains inadequate and targeted conservation programmes are largely absent. This review identifies priority research directions and recommends strengthened multi-stakeholder conservation strategies, including marine protected area expansion, fisheries management reform, and community-based monitoring initiatives. Strengthening India's contribution to global sea snake research is essential given the country's biogeographic position at the confluence of three major ocean systems.

Carbon Dots for Wastewater Treatment: Mechanisms, Challenges and Future Perspectives

Nishtha Naudiyal — 2026-06-01

The growing global water crisis emphasizes the dire need for sustainable and eco-friendly technological innovations to ensure clean water availability not only for the current generations but also for future generations. Carbon dots (CDs), a class of carbon based nanomaterials (CBNs) offers a sustainable solution for wastewater treatment because of their distinctive physicochemical and biological properties. This review critically evaluates the production methods of CDs, ranging from top-down to bottom-up production methods and systematically analyzes their properties. CDs present distinct benefits such as low inherent toxicity, high water dispersibility, photoluminescence tunability and environmental acceptability, making them viable candidates for pollutant detection and removal via adsorption, catalysis, filtration and biological treatments. A bibliometric analysis highlights expanding academic research interest; however, practical, real-world limitations continue to hinder industrial-scale deployment. Despite their laboratory-scale performance, several unresolved issues are to be addressed before commercial translation can occur. These bottlenecks include poor batch-to-batch reproducibility, inconsistent quantum yields, high purification complexities, long-term operational instability and a lack of validation under real wastewater conditions. Furthermore, the majority of current literature is confined to synthetic, single-pollutant aqueous systems, neglecting the matrix complexities of real industrial effluents. This review critically analyzes these deficiencies and identifies key research gaps concerning protocol standardization, environmental toxicity, cost-effective recovery and techno-economic feasibility. Future development pathways, including scalable green synthesis and automated optimization, are proposed to bridge the gap between laboratory discovery and large-scale engineering applications.

Evaluating Climate Change Impacts on Water-borne Disease Prevalence in India: A Narrative Review

Dharmendra Kumar — 2026-06-01

Water-borne diseases remain an enduring and significant public health challenge in India, responsible for considerable morbidity and mortality across all age groups, with children under five bearing the greatest burden. Against this backdrop, the accelerating effects of anthropogenic climate change are altering the hydrological, ecological, and social conditions that govern pathogen transmission. This narrative review synthesises peer-reviewed epidemiological, microbiological, and environmental health literature published between 2000 and 2025 to evaluate how observed and projected climate trajectories—including rising temperatures, intensifying monsoon precipitation, more frequent and severe flooding, and prolonged drought—are influencing the prevalence, distribution, and seasonality of major water-borne diseases in India. A narrative review methodology was adopted to synthesise multidisciplinary and heterogeneous literature on climate change and water-borne diseases in India using evidence retrieved from databases including Web of Science, Scopus, PubMed, Google Scholar, IndMED, WHO Global Index Medicus, Global Environmental Health, CINAHL, and FAO AGRIS, along with authoritative institutional sources. The principal diseases examined are cholera, typhoid and enteric fevers, hepatitis A and E, leptospirosis, and diarrhoeal illness of diverse aetiology. The review identifies several well-supported mechanisms connecting climate variables to disease risk, including temperature-driven amplification of pathogen survival and replication, flood-mediated contamination of drinking-water sources, and drought-induced deterioration of water quality and supply. Regional analyses reveal that the Ganges–Brahmaputra basin and coastal eastern India face the most acute and best-documented risks, while southern India and the semi-arid west present distinct but equally serious vulnerabilities. The compounding role of inadequate water, sanitation, and hygiene (WASH) infrastructure, persistent poverty, and socio-economic inequality is emphasised throughout. Evidence for adaptation strategies—including climate-resilient WASH design, point-of-use treatment, targeted vaccination, improved disease surveillance, and climate-informed early warning systems—is reviewed and found to be promising but underimplemented. Significant research gaps remain, particularly regarding causal attribution, prospective cohort data, and disease modelling tailored to Indian conditions. The findings underscore the urgency of integrating climate considerations into India's public health planning and infrastructure investment.

Environmental Impact Assessment of some Gas Field Waste Disposal Zones in Bangladesh by Environmental Indicators

Mahbuba Begum — 2026-05-21

Heavy metal accumulation in sediments and soils near industrial and energy production zones is receiving increased attention from recent studies. In Bangladesh, rapid industrialisation and energy extraction are intensifying environmental contamination risks within surrounding ecosystems. Limited studies exist on the elemental composition of both surface environmental samples and deep gas reservoir core samples in Bangladesh, particularly regarding the potential contamination transfer from subsurface formations to the surface environment. The objective of this study is to assess the concentration and distribution of toxic elements in gas field environmental samples and reservoir core samples in Bangladesh. A study of probable contamination of 15 elemental abundances from gas reservoir-well to surrounding environment of Saldanadi and Fenchuganj gas fields was conducted using the EDXRF technique. Seventeen samples, including nine environmental soil/sediment and eight gas well core samples from the two gas fields in Bangladesh, were collected for elemental analysis. Environmental contamination was assessed using enrichment factor (EF), geo-accumulation index (Igeo), and contamination factor (CF), with upper continental crust values as baseline data. High contamination factor values, severe enrichment and moderate to heavy geo-accumulation for average elemental abundance of both As and Pb in soil and sediment samples were found in both gas fields, except for a very high Pb (1675ppm) concentration in one soil sample location, where used-up batteries of vehicles of Saldanadi gas field were also dumped. Well-core samples data revealed that gas-abstraction can be contaminated more by toxic metals/metalloids, suggesting considerable risks.

Assessment of Microbial Load of Produced Sachet Water in Ozoro Community, Delta State, Nigeria

J. O. Orogu — 2026-05-22

This study assessed the microbial load of produced sachet water in Ozoro Community as a means to determine the microbial concentration of produced sachet water. The grab method of water sampling was employed in the collection of sachet water samples around Ozoro community. These samples were collected from different retail outlets and labeled with codes ranging from SW-1 – SW-7. The samples transported immediately to the laboratory for analysis. The results obtained showed that the microbial loads ranged from 0.5MPN/100ml to 20MPN/100ml across the sachet water sample for coliform. The observed presence of coliform in the sachet water samples can be attributed to a gap in production/treatment process as well as failure of some production facilities to adhere to good sanitation practices and/or contamination of water wells by pollution sources. In conclusion, the sachet water samples in Ozoro community are unsafe for direct drinking and should not be consumed since microbial growth may persist in them overtime.

Seasonal Dynamics of Physicochemical Characteristics and Nutrient Enrichment in a Tropical Mangrove Estuary, South-Eastern, Nigeria

Samuel Udo Morrison — 2026-05-22

Mangrove estuaries are dynamic ecosystems influenced by complex interactions between freshwater inflow, tidal exchange, nutrient cycling, and anthropogenic activities. This study investigated the seasonal dynamics of physicochemical characteristics and nutrient enrichment in the Imo River Estuary, South-Eastern Nigeria, from September 2023 to February 2024. Five sampling stations were monitored across wet and dry seasons to evaluate spatial and temporal variability in water quality parameters and nutrient distribution. Results showed significant seasonal variation (p < 0.05) in most physicochemical parameters, while spatial differences were station-dependent. Water temperature increased significantly from 29.3–30.7 °C in the wet season to 31.7–32.0 °C in the dry season across all stations. pH shifted significantly (p < 0.05) from slightly alkaline conditions (7.87–8.23) in the wet season to acidic conditions (5.60–5.78) in the dry season. Total dissolved solids (TDS) exhibited strong spatial and seasonal variation (p < 0.05), reaching a peak of 6852.67 ± 457.07 ppm at Station 1 during the wet season and significantly lower values (e.g., 2513.67 ± 142.80 ppm) at downstream stations. Transparency showed moderate spatial variability during the wet season but no significant seasonal difference (p > 0.05). Nutrient concentrations displayed highly significant seasonal enrichment (p < 0.05), with ammonium (NH₄-N) peaking at 92.24 ± 2.21 mg/L and total nitrogen (TN) reaching 170.03 ± 4.30 mg/L during the dry season, indicating strong eutrophic tendencies. Phosphate and total phosphorus exhibited significant spatial redistribution (p < 0.05), linked to sediment-water interactions and reduced tidal flushing, particularly in the dry season. Silicate concentrations were significantly higher during the wet season (p < 0.05) due to increased riverine input. Chlorophyll-a concentrations ranged from 0.23 ± 0.09 to 1.20 ± 0.37 µg/ml in the wet season and 0.50 ± 0.02 to 0.75 ± 0.08 µg/ml in the dry season, with significant spatial variation (p < 0.05) reflecting localized phytoplankton productivity. Principal Component Analysis (PCA) revealed that nutrients (TN, NH₄-N, PO₄-P), TDS, and transparency were the major drivers of seasonal water quality variability. Although limited to a six-month sampling period and five stations, these findings underscore the dominant role of hydrological seasonality, nutrient loading, and internal biogeochemical processes in regulating water quality in the Imo River Estuary. The study provides essential baseline data for monitoring, ecological assessment, and sustainable management of tropical mangrove estuaries in South-Eastern Nigeria.

Zooplankton Diversity in Hanumanthapura Lake, Tumakuru District, Karnataka, India

Mamatha H. C — 2026-05-23

Zooplanktons are microscopic free- floating organisms that transport energy and renew nutrients. They occupy an intermediate position in the food web between primary producers and higher consumers. Zooplanktonic fauna in freshwater lakes includes Rotifer, Cladocera, Ostracoda, Copepods and Protozoa. These communities serve as vital bioindicators in freshwater ecosystems and rapidly respond to environmental changes. The current study was conducted from December 2023 to November 2024 in Hanumanthapura Lake, Tumakuru District, Karnataka, India. This current study identified twenty taxa of zooplankton at five different sites from study area, which are grouped into Rotifer, Copepod, Cladocera and Ostracoda. Among these Rotifers were most dominated with ten species followed by Cladocera with five species, Copepod three species and Ostracod two species. Hanumanthapura lake has been contaminated as a result of ongoing human activities and agricultural runoff from the surrounding area. It is necessary to take up the sustainable steps to monitor and conserve diversity of zooplankton by regular monitoring and examination of water quality. This study concludes that analysis of zooplankton biodiversity will be a useful tool for monitoring the health (water quality) and productivity (fishery potential) of this lake ecosystem for future use and further studies are needed to identify the other biological communities in Hanumanthapura Lake.

Floristic Composition and Community Dynamics of Gebar Grassland in Bhavnagar District, Gujarat, India

Krishna Gadhvi — 2026-05-26

Semi-arid grasslands are among the most ecologically significant yet understudied biomes of the Indian subcontinent, providing critical ecosystem services including carbon sequestration, soil stabilisation, and biodiversity support. This study presents a comprehensive three-year phytosociological assessment of the Gebar semi-arid grassland, Bhavnagar District, Gujarat, conducted across three ecologically distinct seasons Summer (pre-monsoon), Monsoon (rainy season), and Winter (post-monsoon), spanning 2023 to 2025. Using a spatially explicit 500 m × 500 m grid-based sampling framework implemented in QGIS, vegetation data were collected from 175 quadrat visits (1 m × 1 m, 5 grids × 5 quadrats × 7 season-year combinations), covering Winter 2023 and all three seasons of 2024 and 2025. A total of 23 plant species and 971 individual plant records were documented, dominated by the family Poaceae. Species richness ranged from S = 6 (Summer 2025) to S = 13 (Winter 2023 and Monsoon 2025). Shannon–Wiener diversity (H′) ranged from 1.507 to 2.210, with Monsoon seasons consistently yielding the highest values. Sehima sulcata (Hack.) A.Camus was the overwhelmingly dominant species (IVI = 50.59), nearly double the second-ranked Apluda mutica L. (IVI = 27.59). Whittaker's inter-seasonal beta diversity was high in both fully sampled years (βw = 0.966 in 2024, βw = 0.929 in 2025). NMDS ordination (stress = 0.146) and hierarchical cluster analysis confirmed season as the primary driver of community compositional variation. These findings establish a quantitative phytosociological baseline for this under-documented grassland and demonstrate the critical importance of multi-season monitoring for accurate biodiversity assessment of semi-arid ecosystems.

Adopting Artificial Intelligence and Machine Learning for Conservation and Animal Ecology in Protected Areas: A Case of Gorillas and Golden Monkeys in Mgahinga National Park

Wanyera Francis John — 2026-05-26

The golden monkey (Cercopithecus kandti) and mountain gorillas (Gorilla beringei beringei) is listed as endangered on the IUCN Red list. Despite the growing advancement and application of Artificial Intelligence (AI) and Machine Learning (ML) in wildlife monitoring and ecological studies, there remains a significant gap in their effective integration into conservation practices within Mgahinga Gorilla National Park (MGNP). The study aims to examine the potential application of AI and ML in improving data collection, monitoring, and conservation of endangered mountain gorillas and golden monkeys in MGNP, with a focus on assessing current monitoring methods, identifying existing challenges, and exploring how AI and ML technologies can enhance wildlife ecology and conservation efforts in the park. A descriptive research design was adopted, integrating both qualitative and quantitative approaches. Primary data were collected through field observations and structured interviews with park staff, including rangers, guides, trackers, veterinary personnel, and law enforcement teams. Secondary data were obtained from park records, satellite imagery, and existing literature. The study population consisted of 40 staff members, from which a sample of 28 respondents was selected using Slovin’s formula. Purposive and simple random sampling techniques were applied to select participants, with the individual serving as the sampling unit. Data were analysed using SPSS to generate descriptive statistics. The study therefore concluded that the integration of AI and ML-based models is necessary to overcome current limitations by improving data processing, enhancing real-time monitoring, and supporting more accurate and timely conservation decisions. Overall, the study highlights the urgent need for adopting intelligent technological systems to strengthen wildlife monitoring, improve efficiency, and ensure the long-term conservation of endangered species and their habitats in MGNP. The study further recommends that the park invest in modern and updated equipment and tools, including advanced sensors, surveillance systems, and digital monitoring technologies.

Assessment of Microbial and Physicochemical Responses to Spent Engine Oil Contamination across Different Time Intervals in Mechanic Workshops

Chigozie Nwagwu — 2026-05-30

Spent engine oil (SEO) contamination is a persistent and underregulated source of soil degradation in urban and peri-urban environments, particularly within mechanic workshop settings. This study provides a chronosequence-based assessment of the long-term impacts of SEO on soil physicochemical properties and microbial community dynamics across four workshops with operational histories of 1, 5, 10, and 20 years in Choba, Rivers State, Nigeria. Comprehensive analyses were conducted on total petroleum hydrocarbons (TPH), polycyclic aromatic hydrocarbons (PAHs), total heavy metals (THMs), pH, electrical conductivity (EC), total organic carbon (TOC), total organic nitrogen (TON), and culturable bacterial populations, including total heterotrophic bacteria (THB) and hydrocarbon-utilising bacteria (HUB). Results revealed a pronounced temporal contamination gradient, with significantly elevated concentrations of TPH (up to 3,272 mg/kg), PAHs (up to 46.02 mg/kg), and THMs in older workshop soils (p < 0.05), indicating cumulative pollutant loading over time. Contaminated soils exhibited progressive acidification and depletion of TON, alongside increased TOC, reflecting altered nutrient balance and organic matter accumulation. Microbial assessments showed a marked decline in THB abundance with increasing contamination age, whereas HUB populations were selectively enriched, indicating adaptive shifts toward hydrocarbon-degrading taxa. Correlation analyses demonstrated strong positive associations among TPH, PAHs, and THMs (r = 0.99), alongside a negative relationship between TPH and TON, suggesting tightly coupled chemical accumulation and biological response processes. Regression modelling further indicated that TPH exerts a significant inhibitory effect on general microbial biomass, while TOC contributes positively but insufficiently to microbial resilience. Collectively, these findings highlight that prolonged SEO contamination promotes the co-accumulation of hydrocarbons and heavy metals, disrupts soil nutrient cycling, and drives microbial community restructuring toward specialised degraders without achieving effective natural attenuation. This study identifies mechanic workshops as long-term contamination hotspots and underscores the urgent need for systematic monitoring, improved waste-oil management practices, and targeted remediation strategies to mitigate escalating ecological and public health risks.