ABSTRACT
Rapid unplanned development of industries and intensive agriculture are causing overexploitation of environmental resources including land, water, fossil fuels, and so on, which is resulting in changes of the land use/land cover of the earth’s surface. Intensive agricultural practices using an excessive amount of fertilizers and of pesticides to increase the production of crops have led to the eutrophication of water bodies. In view of the significant importance of wetlands, an attempt has been made to analyze the impact of land use/land cover changes on the dynamics among nutrients in the Kabar Tal wetland located in the Begusarai district of Bihar. The impact assessment has been carried out by analyzing land use/land cover changes through multispectral, multitemporal (1990, 2010, and 2015) data in the Kabar Tal wetland and the changes in nutrient concentration during these periods. The study shows that the land use/land cover changes in the catchment have significantly affected the Kabar Tal wetland area. Drastic increases in agricultural land (10.95%) and fallow land (3.73%) have been observed during these periods. Open water cover decreased significantly by 7.22% from 1990–2015. In addition, increasing trends of major nutrients were reported during the 25-year period. These increases in nutrient concentrations correlate positively with the increase in agricultural area and negatively with water quantity. Overall, the wetland suffered serious loss during the 25-year period due to changes in land use/land cover, especially from unregulated agricultural activities. The unplanned intensive agricultural activities have led to the inflow of huge of fertilizers (nutrients), which have significantly increased nutrient concentrations while significantly decreasing the open water area, which indicates the shrinking of the wetland.
