祁连山地区生态系统服务间权衡的社会-生态环境响应机制研究

生态系统服务间权衡和协同关系存在显著的空间异质性，现有研究较少从社会-生态环境的角度进行分析，难以对将生态系统服务纳入实际政策制定过程中。以祁连山地区为研究区，利用InVEST模型和CASA模型对2019年五项调节服务（碳固定、碳储存、产水量、土壤保持和水质净化）和一项支持服务（生境质量）进行计算，结合多元回归树分析法，研究服务间关联的空间异质性及其对社会-生态环境的响应。结果显示，全区尺度上六项服务间呈协同关系，主要受到土地利用类型、降雨和植被覆盖度的影响。植被覆盖区的服务供给量整体高于无植被覆盖区。研究区可被分为5个聚类，不同聚类内服务间关联存在差异。无植被覆盖且年均降雨量低于440.2 mm的区域与植被覆盖度高于0.559的非耕地区内，服务间关联均呈显著协同，后者服务整体较高。降雨升高可促使无植被覆盖区内产水量和土壤保持与其他服务间呈权衡关系，植被覆盖度较低或耕地区内服务间关联变弱。研究成果可为生态管理和政策制定提供有效参考。

The trade-offs among ecosystem services and their response to socio-ecological environment in Qilian Mountains

Significant spatial heterogeneity exists in the trade-offs and synergies among ecosystem services （ESs）. Rare studies have analyzed it from the aspect of socio-ecological environment， thus failed to integrate ESs into ecosystem management. Using Qilian Mountains as the study area， we have quantified six critical ESs （carbon storage， carbon sequestration， water yield， soil retention， nutrient retention and habitat quality） through InVEST model and CASA model， then explored the spatial heterogeneity of ES trade-offs and their response to socio-ecological environment through multivariate regression tree. The results suggested that synergies exist among these six ESs at regional scale， which were mostly impacted by land use pattern， precipitation and vegetation coverage. ESs in regions covered by vegetation were higher than the one without vegetation coverage. The whole region can be divided into five ES bundles， while the interactions among ESs differed in different bundles. Specially， significant synergies among six ESs in ES bundle 1 （areas without vegetation coverage and annual precipitation lower than 440.2 mm） and ES bundle 5 （non-cropland areas with higher vegetation coverage than 0.559）. Increased precipitation would drive the trade-offs between the two ESs of water yield and soil retention and other four ESs in areas without vegetation coverage， while ES relationships tended to weaken in areas with lower vegetation coverage or in cropland. The results could provide useful suggestions for ecological management and decision making.