退耕还林工程对四川盆周低山丘陵区生态系统服务价值的影响——以洪雅县为例

Impact of Grain for Green Project on Ecosystem Service Values in the Hilly Region in Sichuan Basin:A Case Study of Hongya County

退耕还林工程是我国实施的重点林业生态工程。以四川盆周低山丘陵区退耕还林工程重点示范县洪雅县为研究对象,基于遥感和地理信息系统技术,参照中国陆地生态系统单位面积生态系统服务价值当量表,结合研究区粮食平均产量和收购价格,分析了退耕还林前(1994—1999年)、后(1999—2007年)的生态系统服务价值变化,探讨了退耕还林工程对生态系统服务价值的影响。结果表明:退耕还林工程在一定程度上使土地利用程度呈减弱趋势,土地利用处于衰退阶段;退耕前,生态系统服务价值变化不明显;退耕后,生态系统服务价值发生显著变化,总生态系统服务价值增加2.90×108元,可能是由于退耕还林使耕地生态系统服务价值降低,林地生态系统服务价值增加;各项生态功能服务价值中,食物生产功能价值下降,其它各项功能价值上升,以水源涵养功能上升最大,水源涵养价值增加0.78×108元;敏感性分析表明,研究区生态系统服务价值对生态系统服务价值系数变化缺乏弹性,研究结果具有稳定性。

Grain for Green Project is the most critical forestry ecological program of China.In this paper,a case study of the Hongya County in the hilly region in Sichuan Basin by using RS-GIS techniques and referencing the table ecosystem service value per unit area of Chinese terrestrial ecosystem,and combining with the local grain yield and grain purchasing price,this paper analyzed the changes of ecosystem service value between 1994-1999 and 1999-2007,two stages before and during the implementation of Grain for Green Project,and explored the impact of Grain for Green Project on ecosystem service values.The results show that the land use has been declining by the reason of Grain for Green Project;the magnitude of land use exhibited a decreasing trend of the study area.The ecosystem service values changed slightly in 1994-1999,but the ecosystem service values changed tremendously in 1999-2007,the total ecosystem service values increased by 2.90×108 yuan,the possible reason was farmland ecosystem service value decreased and wood land ecosystem service value increased.Each ecosystem service value was increased except food production,and the water supply value increased most,the water supply value increased by 0.78×108 yuan.Sensitivity analysis indicated that the estimated total ecosystem services value in the study area was inelastic to the services value coefficients change,and the results shown in this study were stable.