Comprehensive Benefit Evaluation on Grain for Green Project in Loess Hilly Region of Southern Yulin

Taking six counties, Mizhi, Suide, Jiaxian, Wubao, Qingjian, and Zizhou County, located in southern Yulin of Shaanxi Province in Loess hilly region as a case, the comprehensive benefit has been evaluated since the grain for green project was implemented for 10 years from 1999. The results showed that the benefits of preventing soil erosion and keeping fertility, carbon fixing oxygen replacement, and water conservation covered 99% with the total ecological benefit of these projects implementation. The contribution coefficients of project implementation on agricultural structure adjustment were 505%, 930%, 42%, 470%, 50% and 360%, respectively. The influence degree of project implementation on transferring surplus agricultural labor force were 11 persons/hm2, 21 persons/hm2, 11 persons/hm2, 2 persons/hm2, 03 person/hm2 and 32 persons/hm2, respectively. Basically, farmers were satisfied with the implementation of grain for green project. In conclusion, the project not only constructed a comprehensive evaluation system with eight indexes, including preventing soil erosion and keeping fertility, carbon fixing oxygen replacement, water conservation, the contribution coefficients of project implementation on agricultural structure adjustment, the influence degree of project implementation on transferring surplus agricultural labor force, the proportion of primary industry account for county area, the farmers satisfaction, and index of cultivated land pressure, but established the evaluation model of comprehensive benefits from grain for green project using Grey Correlation Degree Analysis method as well. The comprehensive benefits decreases followed the order: Zizhou > Mizhi > Wubu > Qingjian > Suide > Jiaxian.