Challenges of Water Quality Management for Agricultural Development

Summary: Climate change and nutrient pollution have led to increasing frequency, duration, and toxicity of cyanobacterial blooms worldwide. This study investigates whether aquatic vascular plants can inhibit or reduce the massive development of cyanobacteria in reservoirs. The results indicate that floating-leaf plants and free-floating plants may not be statistically effective in controlling cyanobacterial blooms in reservoir ecosystems.

Summary: Urbanization, industrialization, and the loss of freshwater resources have led to an increased awareness of the importance of surface water quality worldwide. The Vietnamese Mekong Delta is facing pressure on the availability of freshwater sources due to limited ground water resources, prolonged droughts, and flooding. This study identified freshwater aquaculture and industrial activities as the main factors influencing surface water pollution in the delta region.

Summary: The Zhuoshui River alluvial fan is an important area for groundwater and agriculture in Taiwan. This study analyzed groundwater level and quality data from 2008 to 2020 and found no significant difference in groundwater level between wet and dry seasons. Except for groundwater temperature, bicarbonate, and total organic carbon, there were no significant differences in other groundwater quality parameters between wet and dry seasons for Aquifer 1 and Aquifer 2. Aquifer 1 was affected by surface water infiltration, leading to significant differences in mean groundwater temperature, major ion concentrations, and nitrate between wet and dry seasons. Nitrate and arsenic pose health risks if groundwater is used for domestic water supply or irrigation in the distal fan area. Climate change has also affected hydrological conditions, making groundwater level a better indicator for understanding groundwater quality variations.

Summary: This study conducted a hydrogeochemical investigation on well water samples from the extent of Karfiguela paddy field. The results showed that the shallow groundwater in the area is suitable for irrigation, with low physical parameters and ion concentrations. However, elevated levels of Cd and NO3- were detected, posing slight to moderate risks. It was also found that the groundwater's mineralization is mainly influenced by anthropogenic agricultural activities, calcite and magnesite alteration, and CO2 dissolution process.

Summary: Chronic kidney disease with uncertain etiology (CKDu) is a growing health problem in Sri Lanka, particularly in dry-zone farming communities that use groundwater for drinking. The quality of groundwater in an area with both high and low-prevalence clusters of CKDu was investigated. The study found that groundwater in the region exceeded recommended limits for various parameters, including EC/TDS, alkalinity, hardness, and Mg2+ content. High fluoride content was also observed in most samples. The water quality index (WQI) values indicated that a significant portion of groundwater samples in both high and low CKDu prevalence regions had poor quality. The spatial distribution of WQI and fluoride concentration overlapped with the CKDu hotspots, suggesting a direct influence of groundwater quality on the prevalence of CKDu.