Integrated runoff and soil loss monitoring unit for small agricultural watersheds

Abstract

Runoff and sediment flow behaviors from small agricultural watersheds on Alfisols and Vertic Inceptisols, and their implications for the design of a runoff and soil loss monitoring unit are discussed. It was observed that a small segment of runoff hydrograph near peak discharge rate usually accounted for 65–85 percent of total storm soil loss. The runoff and sediment flow behavior recorded on the small agricultural watersheds indicated the need for an integrated digital runoff and soil loss monitoring unit (IDRSMU) to achieve higher accuracy and cost effectiveness. The design, development and testing of an IDRSMU to measure both the runoff and soil loss from small agricultural watersheds is presented. Under the field conditions its accuracy and efficiency for monitoring soil loss from small agricultural watersheds was observed good. Use of this integrated unit, makes the estimation of soil loss easy, rapid and accurate. The designed unit does smart runoff sampling by linking the runoff sampling intervals to the sediment load. This significantly reduces number of samples that needs to be collected, thereby reducing the operational cost, without compromising with the accuracy in estimating soil loss from small agricultural watersheds.