干旱区生态环境知识资源中心

Several grassland conservation programs aiming to relieve grazing pressure have been implemented in Inner Mongolia since 2000 to reverse grassland degradation and protect local and regional environments. Previous studies on the effects of these programs usually used small-scale data generated from field experiments and household surveys, inhibiting the discovery of large-scale effects due to spatial heterogeneity. For a typical study region in Xilingol League, we used fixed-effects models and a panel dataset at the county level from 1998 to 2013 to examine the effects of two programs, namely, the Beijing-Tianjin Wind/Sand Source Control Program and the Ecological Subsidy and Award System and other drivers on vegetation rehabilitation. The modeling results suggested that the programs had a positive but delayed impact on grassland vegetation rehabilitation. Enrollment in the two programs in a specific year was predicted to increase the vegetation index value by amounts equivalent to 186 mm and 98 mm more annual precipitation after two years, respectively (p < 0.01). Fixed effects (including site factors and land use history) had a greater effect, hence the design and implementation of government conservation policies should be context-based.