The Swarnamukhi river estuary (SRE), and the surrounding sea in Nellore, southeast coast of India, is one of the least studied marine environments, notably for physicochemical characteristics. Seawater samples were collected from five stations every month from 2014 to 2017 to assess physicochemical characteristics. The open sea (OS) station was significantly different from the inner stations, according to non-metric multidimensional scaling and cluster analysis. The variability was shown by strong factor loadings of atmospheric temperature (0.87), water temperature (0.84), biochemical oxygen demand (0.77), ammonia (0.85), and total nitrogen (0.78). Furthermore, one-way ANOVA and box-whisker plots facilitated simplifying and corroborating multivariate results that showed high concentration in the inner stations. Based on the N/P and Si/N ratios, nitrate and silicate were the key limiting factors in this study. The findings are critical for establishing reference conditions for comparison studies with other comparable ecosystems in the tropical region for better environmental conservation and management.

Lakes are key freshwater ecosystems that maintain the biodiversity, regulate nutrient cycles, and provide habitat for migratory birds. Their ecological well-being is greatly impacted by water quality, which affects the composition and productivity of primary producers such as diatoms. Diatoms are sensitive bio-indicators that respond spontaneously to the changing physical, chemical, and biological parameters. The dynamics of their communities extend through food webs, affecting fish, zooplankton, and, eventually, migratory bird populations. This review outlines the current scientific understanding regarding the relationships between bird communities, diatom ecology, and lake water quality, with a focus on case studies from Tamil Nadu and India. It has been demonstrated that major water quality stressors such as pollution, eutrophication, salinisation, and hydrological changes, disturb diatom assemblages, decrease the availability of prey, and deteriorate vital migratory bird stopover and breeding habitats.

The microplastics and pharmaceuticals and personal care products (PPCPs) interaction is a serious environmental problem that has higher impactson both the ecosystems and human health. The presence of microplastics within various environments and the widespread use of PPCPs, leads to complex that make the toxic compounds more persistent and bioavailable. The large surface area, hydrophobicity, and chemical additives of the microplastics, make them effectively adsorb PPCPs. The PPCPs bioaccumulate in aquatic species as a result, which suppresses the contaminants’ natural breakdown processes. Bioaccumulation can increase the possibility of biomagnification through food webs, which increases the concerns about chronic toxicity. These microplastic-PPCP complexes facilitate wide transportation across aquatic, terrestrial, and atmospheric pathways and therefore contaminate the ecosystems. Persistent pollutants cause harm to biodiversity, disrupt necessary ecosystem services, and affect health through contaminated food and water supplies. Thus, studies have evidenced that microplastics ingested by marine biota result in the desorption of adsorbed PPCPs under diverse environmental conditions and also increase exposure level to harmful products. Furthermore, the use of contaminated aquatic products and contaminated drinking water are likely to also affect human beings, such impacts include: importing ARGs within the gut, which might imply the antibiotic resistance. This study reviews the interaction and the mechanisms that cause long term complexity of microplastic-PPCPs in the environment, emphasizing the necessity to reduce their impact on ecosystems and public health through advanced solutions and policies. Advances in multidisciplinary research and waste management practices are needed to conserve ecosystems and bring in a sustainable future.