http://117.252.14.250:8080/jspui/handle/123456789/1485 2026-04-16T00:24:46Z http://117.252.14.250:8080/jspui/handle/123456789/8028 Microbes’ and Microplastics’ Interactions in Freshwater Ecosystems: Fate and Implications for Environmental Health . Dixit, Shubha; Maurya, Arpita; Singh, Ashutosh; Verma, Sheetal; Singh, Rajesh; Kumar, Manoj Microorganisms play a pivotal role in the biogeochemical cycles of aquatic environment, mediating interactions between biotic and abiotic components and forming complex associations with plastic debris. Their widespread distribution is a global concern due to their movement through food chains, which poses risks to ecosystems and human health, and their capacity to facilitate the spread of infectious microbes in contaminated nvironments. Interactions between micro organisms and microplastics (MPs) can yield both beneficial and harmful effects. Microorganisms, including bacteria, fungi, algae, and viruses are indispensable for nutrient cycling, organic matter decomposition, microplastic degradation, and maintaining overall ecosystem health. Certain bacterial groups, such as Proteobacteria, Cyanobacteria, and Bacteroidetes, are commonly associated with MPs like polyethylene (PE) and polypropylene (PP), while plastics like polyvinyl chloride (PVC) and polystyrene (PS) are less frequently colonized. These bacteria play a crucial role in breaking down large polymer molecules into smaller components and monomers, ultimately leading to mineralization into CO₂, H₂O, and biomass via enzymatic processes. The intricate relationships between microorganisms and microplastics, including microbial colonization, biofilm formation on MPs (commonly referred to as the plastisphere), biodegradation mechanisms, and their broader implications for pollution dynamics and ecological health, underscore the complexity of the issue. While microbial degradation of microplastics offers potential solutions, it faces significant challenges. Despite these challenges, understanding the mechanisms of microbe-MP interactions and their environmental implications remains critical for developing strategies to combat microplastic contamination in freshwater ecosystems. This chapter explores these interactions in detail, focusing on the dual role of micro organisms in mitigating and exacerbating MP-related pollution. By advancing research on microbial processes and environmental variables that influence plastic degradation, it is possible to work toward innovative solutions for managing microplastic contamination and safeguarding environmental health 2025-01-01T00:00:00Z http://117.252.14.250:8080/jspui/handle/123456789/7495 Assessment of Extreme Storm Conditions for an Urban Drainage System Osheen; Kansal, Mitthan Lal; Bisht, Deepak Singh Urban flooding is a combination of natural and anthropogenic hazards which is of major concern to the various stakeholders in society. It causes discomfort and retardation to the fast-moving life of the urban conglomerate and poses a challenge to the water professionals. A drainage network is designed and installed in a city to quickly drain off the excess runoff from the catchment without causing any disturbance to the life. This study focuses on the frequency analysis of past rainfall data and assesses the extreme storm condition for a typical drainage system. Multiple scenarios for simulating rainfall-runoff response to different shapes of hyetograph were studied to analyze the performance of the drainage system. The hyetograph peaks of design storms were primarily rearranged to different time steps of simulation period to study the change in overall response of urban drainage system in terms of flood duration, number of flooding nodes, and flood volume. The MIKE+ is used to conduct a comparative analysis of a part of Gurugram City, Haryana, India, which is a major economic center. The results of the study show that the maximum flood volume is corresponding to the hyetograph designed using the alternate block method. 2024-01-01T00:00:00Z http://117.252.14.250:8080/jspui/handle/123456789/7468 Soil Moisture–Vegetation Stress–Based Agricultural Drought Index Integrating Remote Sensing–Derived Soil Moisture and Vegetation Indices Singh, Gurjeet; Bisht, Deepak Singh Agricultural drought has significant impacts on society and governance, including reduced food production and revenue. Thus, accurate monitoring and assessment of drought is crucial to provide an early warning system for socioeconomic impacts resulting from prolonged moisture deficit. Although meteorological drought provides a potential signature for water availability, it is insufficient to fully characterize agricultural drought. More efficient calculation and assessment methods are required that account for cropping patterns, soil characteristics, and soil moisture patterns to reflect actual crop water stress. To address this need, an integrated approach called the Soil Moisture–Vegetation Stress-Based Agricultural Drought Index (SVADI) is discussed herein. The approach utilizes remote sensing observations of soil moisture and vegetation to derive soil moisture and vegetation stress-based drought indices. Shannon's entropy formula is employed to dynamically combine the indices and determine their relative importance. Findings of the study establish SVADI as an effective tool for accurately assessing agricultural drought in the region. The study focuses on eastern India, consisting of five Indian states (Bihar, Jharkhand, Chhattisgarh, Odisha, and West Bengal), which can also be implemented elsewhere. 2023-01-01T00:00:00Z http://117.252.14.250:8080/jspui/handle/123456789/7116 Environmental Tracers in the Identification of the Groundwater Salinity—Case Studies from Northwest India Krishan, Gopal; Kumar, Bhishm; Rao, M. S.; Yadav, Brijesh K.; Kansal, M. L.; Garg, Rahul; Kumar, Mohit; Kumar, Ravi In the face of the burgeoning climate crisis and ever-increasing human consumption demands, the disparate distribution of the water cycle is greatly amplified, resulting in frequent extreme events like drought and flooding. Groundwater is the essential component of this water cycle which interacts with all other parameters. Several large aquifers worldwide face huge water scarcity due to excessive groundwater pumping for agricultural and industrial demand, reduced infiltration capacity due to land-use changes, and human-induced climate crises. The sub-surface component and the stream discharge of major rivers, supporting massive civilizations, are on the verge of drying up due to decreased base flow. Groundwater has been largely used as a major source of irrigation water. Its excessive use and a change in cropping pattern have led to its declination in quantity and deterioration in quality (MacDonald et al. 2016; Siebert et al. 2010; Wada et al. 2014). In addition to the anthropogenic contaminants in groundwater such as nitrates, pesticides, feeds (Burow et al. 2008; Harter et al. 2012), and geogenic pollutants such as arsenic, uranium, fluoride (Jurgens et al. 2010; Ravenscroft et al. 2013; Smith et al. 2018) groundwater is also contaminated by total dissolved solids (TDS) occurring naturally or anthropogenically cause groundwater salinity (Triki et al. 2014). One significant impact of low water quantity is on surface–subsurface water quality. In conditions of low aquifer recharge, the incomplete dilution of dissolved solids in groundwater leads to a spike in TDS levels inside the aquifer. 2022-01-01T00:00:00Z