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Introduction: Bottom sediments play a pivotal role in wetland productivity, and here, eight Gangetic floodplain wetlands of India were studied to assess the sediment physicochemical characteristics and textural analysis. Methods: Sediment samples that were collected from each wetland in monsoon and non-monsoon seasons were analysed. ANOVA, Principal component analysis and multiple correlation analysis were used for statistical analysis. Results and Discussion: Throughout the study period, pH (6.90-8.04), EC (0.20-1.64 dS/m), CaCO3 (1.75%-14.50%), available nitrogen (10.22-22.23 mg/ 100 g sediment), total nitrogen (80.4-333.8 mg/100 g sediment), available phosphorus (0.20-5.61 mg/100 g sediment), and total phosphorus (19.63-173.33 mg/100 g sediment) were recorded. The sediment quality parameters differ significantly (p > 0.05) among the wetlands. Seasonal variation was only observed on total nitrogen and total phosphorus contents. Sediments were dominated by sand. Sediment nutrient (C, N, and P) stoichiometry of wetlands depicted a comparatively little higher C/P (5.96-66.32) ratio and lower C/N (3.34-22.76) and N/P (1.12-9.25) ratios, which revealed that the physicochemical characteristics of the sediments are influenced by anthropogenic sources. Principal component analysis showed the influence of both natural and anthropogenic causes on wetland ecosystems. The geographic information system (GIS) interpolation approach was used in combination with laboratory analysis methods to give a complete spatial resolution of the sediment quality of each wetland. The study suggests that these wetlands' sediment quality is favorable for fish culture but requires proper management practices to achieve sustainable production. As it is the first time where monitoring physicochemical properties of sediments of these wetlands are presented, this study can be used as a baseline data for comparison in future environmental assessments of the wetlands. [ABSTRACT FROM AUTHOR]

The article discusses the use of fishing pesticides on the lucrative giant freshwater prawn Macrobrachium spp. in the River Ganga in India as of 2024. Topics covered include the illegal fishing that renders the fishes caught dangerous for human consumption, and the practice's irreversible adverse effects on aquatic ecosystems. Also noted is the need to upgrade awareness on pesticide use and to enforce strict fishing regulations to maintain the natural river system.

For natural ecosystems as well as human development, freshwater bodies like reservoirs are critically important. Krishnagiri reservoir, a moderately impacted tropical reservoir of India, is an important source of freshwater. However, eutrophication status due to anthropogenic activities is a major threat to this reservoir. This endeavour aimed to determine the spatio-temporal differences for selected (21) limnological parameters along with trophic status of Krishnagiri reservoir for its sustainable management. Samples (water and plankton) were collected from 11 sites covering entire reservoir during pre-monsoon, monsoon and post-monsoon season. Limnological parameters showed some spatio-temporal variations, the season has more impacts on water quality than sites as evidenced by cluster analysis. Principal component analysis distinguished the seasons based on major influencing water quality parameters. The reservoir trophic status fluctuated from eutrophic to hyper-eutrophic. Water quality index showed that the reservoir falls under unsuitable category. Additionally, cyanobacterial bloom formation was observed in all the seasons, with dominance of Microcystis sp. This investigation can be used as a baseline for studies pertaining to nutrient and sediment loading, and immediate action is required for employment of integrated management plan to restore this aquatic ecosystem. The study also recommends strategies for sustainable management of the aquatic bioresources. [ABSTRACT FROM AUTHOR]

Agricultural practices can change soil properties and the amount of runoff generated from a landscape. Modeling results could be significantly different than expected if the web soil survey or other commonly used remote sensing applications are used as model inputs without site verification. This study assessed the applicability and sensitivity of the Soil-Plant-Air-Water (SPAW) Model for simulating the runoff (%) and infiltration (%) components of the water balance for various soil physical properties, cover crop, and weather variables. Soil profiles in 135 combinations were developed with three soil classes (sandy loam, silt loam, and clay), five organic matter levels (1%, 2%, 3%, 4%, and 5%), three levels of compaction (low, medium, and high), and three topsoil layer thicknesses (7.6 cm, 11.4 cm, and 15 cm). Also, three cover crop treatments were simulated by modifying surface cover and evapotranspiration during the non-growing season. Finally, two precipitation regimes were considered (Iowa City, IA, as high precipitation and Brookings, SD, as low precipitation) to simulate runoff and infiltration. In total, 810 scenarios were run, resulting in over 300 million data points. This study confirmed that soil texture, bulk density, and topsoil thickness significantly (p<0.01) influence runoff generation and infiltration percentage based on the water balance criterion. Interestingly, the SPAW model had no significant response on runoff (%) and infiltration (%) to organic matter levels changing from 1% to 5%. This simulation demonstrates that runoff estimations can be significantly influenced by soil properties that can change due to agricultural conservation practices (ACPs) or, conversely, by compaction events. Inputs to models must account for these changes rather than relying only on historical or remote sensing inputs. [ABSTRACT FROM AUTHOR]