Land use change and soil carbon sequestration in China: Where does it pay to conserve?

Abstract

This paper estimates the impact of land use change on soil organic carbon (SOC) sequestration in China from 1985 to 2005 using a nationwide, georeferenced database on land use, soil, and climate. The method presented here is capable of incorporating site-specific information on soil, climate, and land use change into a national-level analysis. We find that grassland restoration contributed to the largest increase in SOC in China from 1985 to 2005, while grassland degradation caused the largest decrease. Overall, land use change resulted in only a small net increase in SOC, by 7.5 TgC (0.02 %), which is statistically insignificant at the 95 % confidence level. A cost-effectiveness analysis indicates that it is important to consider SOC when assessing land conservation programs. Restoring degraded grassland is more cost-effective than returning dry farmland to grassland. Inner Mongolia is a key region for dense grassland restoration