Impacts of ecological restoration projects on agricultural productivity in China

The changes in cropland quantity and quality due to land use are critical concerns to national food security, particularly for China. Despite the significant ecological effects, the ecological restoration program （ERP）, started from 1999, has evidently altered the spatial patterns of China＇s cropland and agricultural productivity. Based on cropland dynamic data from 2000 to 2008 primarily derived from satellite images with a 30-m resolution and satel- lite-based net primary productivity models, we identified the impacts on agricultural produc- tivity caused by ERP, including ＂Grain for Green＂ Program （GFGP） and ＂Reclaimed Cropland to Lake＂ （RCTL） Program. Our results indicated that the agricultural productivity lost with a rate of 132.67×104 t/a due to ERP, which accounted for 44.01% of the total loss rate caused by land use changes during 2000-2005. During 2005-2008, the loss rate due to ERP de- creased to 77.18×104 t/a, which was equivalent to 58.17% of that in the first five years and 30.22% of the total loss rate caused by land use changes. The agricultural productivity loss from 2000-2008 caused by ERP was more attributed to GFGP （about 70%） than RCTL. Al- though ERP had a certain influence on cropland productivity during 2000-2008, its effect was still much less than that of urbanization; moreover, ERP was already converted from the project implementation phase to the consolidation phase.