Linking climate change to soil loss estimation in the Kosi river basin, India

Abstract

This study assessed the spatio-temporal variability of soil loss based on rainfall–runoff erosivity in the context of climate change in the Kosi river basin. The observed rainfall data (1985–2017) were used for past and present analyses, and the projected rainfall data (2020–2100) interpolated for various general circulation models (GCMs) were used for future analysis. The results of rainfall analysis for the projected period show a maximum percentage variation of 26.2% for a particular GCM and an average of 9.4% increase in the rainfall data from all selected GCMs considering three representative concentration pathways (RCPs). We also evaluated the implications of change in the soil loss due to changes in the rainfall pattern and crop management factor for three time slices. The results for the projected time period showed a concomitant increase in the average soil loss of −13.03–10.39% with respect to the baseline. The average soil loss results for the time period of 2020–2100 are also compared with the average soil loss for each RCP scenario and found very meager changes in the area of soil erosion. The results due to climate change aid in prioritizing the areas with suitable conservation support practices. HIGHLIGHTS To analyze the rainfall pattern using the past, present and projected data.; To understand the relationship between soil loss and rainfall due to the impact of climate change.; To analyze the effect of change in crop cover over soil loss due to climate change.;

Keywords

• climate change
• crop management
• kosi river basin
• rainfall–runoff erosivity
• soil erosion