Detecting the short term impact of soil and water conservation practices from incomplete monitoring records - A case study from the Tana sub-basin, Ethiopia

Abstract

Efforts to tackle land degradation worldwide have spurred the adoption of soil and water conservation (SWC) practices intended to reduce surface runoff and erosion. Despite their widespread implementation, missing or incomplete monitoring remains a pervasive problem preventing evaluation of how well SWC practices meet these aims. Key metrics to evaluate SWC efficacy are the production of flow per unit rainfall (runoff ratio), and exported sediment (sediment concentration). We develop a method to assess changes in these metrics in the absence of a flow rating curve, using more complete and reliable measurements of stage (flow depth). We apply these methods to incomplete monitoring datasets collected from five watersheds included in the Tana and Beles Integrated Water Resource Development Project (TBIWRDP) in the Abay (Blue Nile) basin, Ethiopia. Changes