A scenario-based analysis of selected best management practices for reduced sediment and nutrient yield in the watershed located in the Shivalik hills, India

Abstract

In this study, an attempt has been made to evaluate the best management practices (BMPs) in a poorly degraded and economically fragile watershed area in Shivalik hills, Northern India. A scenario-based approach was followed to evaluate the existing BMPs and a few hypothetically implemented BMPs based on SWAT modeling. A regionalization approach was adopted for calibrating the SWAT model for ungauged micro-watersheds within the study area. After successful calibration, soil and water assessment tool (SWAT) model was simulated for several BMPs that are in practice such as Check dams, vegetation and fencing so as to learn about their effectiveness in controlling sediment and nutrient yield. Other hypothetically installed BMPs, such as contouring, terracing, grassed waterways and filter strips were also evaluated in untreated micro and sub-watersheds. The cost-benefit analysis of these hypothetical BMPs revealed that the average reduction in nutrients was maximum for grassed waterways and minimum for terracing. Overall, the scenario-based analysis revealed that conservation practices, in the otherwise degraded watershed, can prove to be beneficial for sustainability of its natural resources.