Human impacts on soil erosion identified using land-use changes: A case study from the Loess Plateau, China

摘要

Human impacts on soil erosion are generally reflected in land-use changes. Thus, identifying the characteristics of land-use changes associated with their driving forces has great potential for evaluating regional soil-erosion variations and the impacts of human activities, especially for regions where soil-erosion data are scarce. A case study from Zhifanggou, a small watershed in the hilly area of the Loess Plateau, China, is conducted through a systematic analysis of temporal variations in land-use patterns from 1938 to 1999, combined with local soil-erosion observations. Multiple series of land-use data indicate three distinct stages of change in land-use patterns and conversions matching three different periods of soil erosion: (1) pristine conditions before 1938; (2) severe degradation between 1958 and 1978, and (3) gradual rehabilitation from 1978 to 1999. The trends and styles of land-use changes and soil erosion are primarily driven by regional policy, with abrupt changes during policy transformations and stability between policy changes. Other socioeconomic factors also contribute to land-use changes during periods of stable policy. This suggests that policy should be established cautiously, because an unsuitable strategy may lead to greater degradation in ecological quality than other factors.