Effect of Heavy metal pollution on river Ganga water and sediments
The Ganga is India’s most significant river system. The abundant supply of water throughout the year has played a significant role in the development of Indian civilization and economics. It accounts for 25% of India’s total water resources. The Ganga is the world’s thirty-first-longest river, with a basin size of 861,404 km2. (Siddiqui & Pandey, 2019). In India, the Ganga River flows through 29 class I cities, 23 class II cities, and around 50 towns, resulting in the discharge of various sorts of contaminants such as industrial, sewage, and so on into this enormous river eco-system. Most heavy metals enter rivers from a variety of sources, which can be both natural (due to erosion and weathering) and human (due to pollution). Natural sources of heavy metals from leaching and weathering of rocks in the environment are normally of minor consequence in light of the strong human activity. The precipitation of heavy metal carbonates, hydroxides, and sulfides, which settle and become part of the sediment, causes the presence of heavy metals in sediments. The most prominent anthropogenic sources of heavy metals are various industries and household sewage. The practice of dumping waste from industry and untreated household sewage into the aquatic ecosystem is still in place, leading to an increase in heavy metal concentrations in river water. In recent years, much study has been undertaken on Ganga contamination caused by heavy metal pollution. An overview of several noteworthy research for the previous 37 years has been published below (Table 4), which demonstrated the damage to Ganga River quality and its related flora and fauna from the last decade to the present.
Table 4: Summary of the research findings on heavy metal pollution in Ganga