黄土高原丘陵沟壑区脆弱农业生态系统服务评价——以安塞县为例

Valuation of fragile agriculture ecosystem services in loess hilly-gully region:a case study of Ansai county

论文以典型黄土高原丘陵沟壑区安塞县为例,运用市场价值法、替代工程法、影子价格法、机会成本法等方法对其境内7种不同类型农业生态系统的保持土壤(Es)、涵养水分(Ew)、固定CO2和释放O2(Ea)、维持营养物质循环(En)、净化环境(Ee)等服务功能进行了价值核算,初步估算出安塞县生态系统各服务功能的价值总量为3169870.46×104元,是其农林产品服务价值(Vp)的170倍。这一方面表明脆弱生态系统依然担当了重要的生态系统服务功能,为其经济生产力提供了巨大的生态服务。各种服务价值的大小依次为En(占89.85%)、Ew(占4.39%)、Ea(占4.18%)、Vp(占0.58%)、Es(占0.81%)、Ee(占0.18%)。另一方面也充分反映出在该地区“生态生产力”与“经济生产力”严重失衡。

Much research work has been done since the introduction of the conception of the eco-system services.However most of the work has been focused on macroscopic(global or national)scale which could hardly touched upon the fragile agroecosystem disturbed by human,especially the aggravated eco-environmental problem in Loess Plateau because of severe soil erosion and bad natural condition.The present study tries to provide some new references for rehabilitating e-cological environment and improving productivity of the agroecosystem.Using different methods such as market value,substitution engineering,shadow price,opportunity cost,this article calcu-lated the value of agriculture ecosystem services including conserving soil (Es )and water (Ew),fixation of CO 2 and release of O 2 (Ea ),maintaining nutrient circling(En)and decontaminating en-vironment(Ee )in Ansai county of loess hilly-gully region.The results showed that the gross value of ecosystem service was31698.70million yuan,or170times of production value(Ep).This implied even the fragile ecosystem displayed an important service function though it had been disregarded in a long period of time.In Ansai county agriculture ecosystem provided great eco-logical services for economic productivity.Various services values respectively were En2848141.82ten thousand yuan(89.85%),Ew139136.26ten thousand yuan(4.39%),Ea 132511.32ten thousand yuan(4.18%),Vp18505.66ten thousand yuan(0.58%),Es 25824.60ten thou-sand yuan(0.81%),and Ee 5750.80ten thousand yuan(0.18%).On the other hand,this also showed that there was imbalance between ecological productivity and economic productivity in the study area,which was a general problem throughout the Loess Plateau region.So the effec-tive way in rehabilitating ecological environment is to enlarge grassland and forest area so as to improve soil and water conservation function.