Climate change can disrupt the hydrological system and jeopardize the security of water resource management. Several issues influence the hydrological system, such as groundwater overexploitation, water table depletion, crop diversity, land-use patterns, and saltwater intrusion. The review considered over 400 related pieces of published literature to extract expressive information to understand the present scenarios of possible climate change impacts on water resources. The result showed that temperature rises and high-intensity rainfall events mobilize pollutants like nutrients and sediments into the freshwater, particularly the surface water. It also showed that water quality parameters like electrical conductivity, suspended solids, nitrate, sulfate, ammonium, magnesium, calcium, water acidity, organic carbons, pathogens, and micropollutants are steadily rising with climate change, especially in worldwide inland water bodies. Instead, reducing water flows will enhance residence time in upland rivers and lakes, which creates conditions for harmful algal blooms that decrease saturated oxygen levels. The probable impacts of climate change on sustainable water management have received much attention, but there is relatively little understanding of the concurrent changes in both surface and groundwater chemistry. Along with planning and management aspects, the study findings will help inform measures to improve water quality, health risk assessment, remediation, and adaptation actions.

Watershed models are useful in estimating the effects of management practices on both water quantity and quality. These models aid stakeholders and policymakers in managing water resources by informing them of the basic model structure and parameter interactions. For this study, the soil and water assessment tool (SWAT) was used to simulate streamflow, total nitrogen (TN), and total phosphorus (TP) in the steep and forested Ogouchi catchment. The parameter uncertainty and sensitivity of the models were then assessed using the sequential uncertainty fitting (SUFI-2) algorithm. This study demonstrated how SWAT can be used to estimate the nutrient load and hydrologic condition in a small archipelagic watershed where the entire hydrologic process is different from continental catchments. Results showed that the parameter uncertainty is highest for simulating TP (p-factor = 0.58–0.46, r-factor = 2.00–9.71) as compared with TN (p-factor = 0.85–0.54, r-factor = 0.91–3.27). Meanwhile, the sensitivity analysis revealed that nutrient loads are most sensitive to the SCS runoff curve number and average steepness, which are streamflow-related parameters. Overall, this study showed that nutrient loads are highly sensitive to streamflow-related parameters, which suggests that stabilizing runoff and sedimentation rates along the watershed is necessary to maintain good water quality in the reservoir.

This study was done by using three basic coagulating agents for solid-liquid separation processes to reuse the industrials effluent treatment plant wastewater and reduce an effective amount of chemical consumption as well as cost for treatment of ceramics industries wastewater. The experiment was conducted using jar tester to determine the optimum doses of poly aluminum chloride, alum and lime for treatment of industrials wastewater. The three basic concentration was used in this investigation which were 1% liquid poly aluminum chloride, 2% potassium aluminum sulfate, 4% calcium hydroxide. here 0.05% polyacrylamide was added with each chemical dose as coagulant. These three coagulating substances were used successfully to make the wastewater reusable. The turbidity, color hazen and total suspended solid was reduced up to 90%, 91% and 99.5% respectively. Among those chemicals only 1% liquid poly aluminum chloride dosing was more effective both in physic-chemical and economic suspects for removing significant amount of turbidity, color hazen and TSS. On the other hand, this chemical consumption was lower than that of others. This investigation suggests that using 1% liquid poly aluminum chloride coagulation agent is cost effective treatment process which may be a useful in primary water treatment process for the industrials wastewater.

The oxygen radical absorbance capacity (ORAC) was used to evaluate the antioxidant activity of conventional activated sludge. Protein and ORAC assays showed that extracellular polymeric substances (EPS) accounted for ~80% of the total protein extracted from conventional activated sludge and ~50% of the total ORAC. The detection of ORAC and superoxide dismutase activity suggests that EPS potentially possess antioxidant capacity. The intracellular antioxidant activity of conventional activated sludge in a municipal wastewater treatment plant was investigated. The activated sludge showed larger variations in ORAC in tanks without aeration than with aeration, which may be attributed to variability in oxygen diffused from the atmosphere and organic matter available for each bacterium. In addition, the variation in ORAC of tanks with aeration gradually decreased over time, which may be attributed to the generation of reactive oxygen species and the production of antioxidants balancing out the decrease in organic matter concentration. However, in a laboratory-scale experiment, ORAC decreased at 1.5 h under the oxic condition, which may be attributed to less available energy for producing ORAC in the internal storage material.