A Policy-Driven Large Scale Ecological Restoration: Quantifying Ecosystem Services Changes in the Loess Plateau of China

TLDR

Environmental conservation policies are key tools for ecological rehabilitation, yet quantifying their regional effects remains difficult and long‑term sustainability of ecosystem service enhancement is uncertain. The study assesses 2000–2008 changes in four ecosystem services to evaluate the 1999 Chinese ecological rehabilitation initiatives and calls for an adaptive management approach to reduce uncertainty. The authors conducted a regional case study on the Loess Plateau using USLE, hydrological modeling, multivariate analysis, and assessed changes in water regulation, soil conservation, carbon sequestration, and grain production from 2000 to 2008. Farmland conversion to woodland and grassland enhanced soil conservation and carbon sequestration while reducing water yield, yet grain production rose despite reduced farmland, attributed to strong socioeconomic incentives.

Abstract

As one of the key tools for regulating human-ecosystem relations, environmental conservation policies can promote ecological rehabilitation across a variety of spatiotemporal scales. However, quantifying the ecological effects of such policies at the regional level is difficult. A case study was conducted at the regional level in the ecologically vulnerable region of the Loess Plateau, China, through the use of several methods including the Universal Soil Loss Equation (USLE), hydrological modeling and multivariate analysis. An assessment of the changes over the period of 2000–2008 in four key ecosystem services was undertaken to determine the effects of the Chinese government's ecological rehabilitation initiatives implemented in 1999. These ecosystem services included water regulation, soil conservation, carbon sequestration and grain production. Significant conversions of farmland to woodland and grassland were found to have resulted in enhanced soil conservation and carbon sequestration, but decreased regional water yield under a warming and drying climate trend. The total grain production increased in spite of a significant decline in farmland acreage. These trends have been attributed to the strong socioeconomic incentives embedded in the ecological rehabilitation policy. Although some positive policy results have been achieved over the last decade, large uncertainty remains regarding long-term policy effects on the sustainability of ecological rehabilitation performance and ecosystem service enhancement. To reduce such uncertainty, this study calls for an adaptive management approach to regional ecological rehabilitation policy to be adopted, with a focus on the dynamic interactions between people and their environments in a changing world.