LAUSR

Abstract Understanding the soil and water processes and their interactions over time and space has attracted research and policy attention worldwide. But past studies have rarely adopted an interdisciplinary approach to integrating the primary natural and social forces in assessing the causes of soil and water loss or conservation. The purpose of this study is to evaluate the effects of restoring degraded cropland by means of reestablishing forest/vegetation covers and terracing on water and sediment control in the Wei River Catchment, which was notorious for its high erosion rates but has witnessed tremendous improvement since the beginning of the new century. Based on a unique panel dataset covering 44 counties over a period of 16 consecutive years (2000–2015), our simultaneous equations model was able to capture the structural linkages between water runoff, sediment concentration, and sediment transport. To highlight the crucial role of human interventions, a stepwise regression approach was undertaken. Our empirical results show that the reduction of sediment concentration has been driven largely by improved land cover, induced by implementing the Sloping Land Conversion Program, whereas terracing, as part of the Water and Soil Conservation Project, has played a positive role in mitigating runoff and sediment discharge.