甘肃白龙江流域生态系统服务变化及权衡与协同关系

甘肃白龙江流域是长江上游主要的水源涵养区和环境脆弱区,近几十年来高强度的人类活动加剧了生态环境压力,因此开展白龙江流域生态系统服务变化及权衡协同关系研究对该区域的可持续发展具有重要意义。本文通过生态系统服务变化指数（ESCI）、空间自相关、相关系数法,定量分析了1990-2014年甘肃白龙江流域生态系统服务时空变化过程、空间集聚特征及生态系统服务间的权衡与协同关系。结果表明：① 1990-2014年间产水量、碳储量、土壤保持和农作物生产4种典型生态系统服务的ESCI值变化迥异,空间分布各具特色,具体表现为：产水量ESCI极值变化超过1倍且前后两时段（1990-2002年,2002-2014年）分布格局有较大出入,而两时段内的碳储量ESCI值变化相同,分布格局也相似,土壤保持ESCI值两极化趋势较农产品生产不明显,但这两者后一时段均与前一时段的ESCI分布相反;② 4种典型生态系统服务存在空间自相关,局部上正相关类型“组团”出现,集聚性较强,负相关类型散布,集聚性低,空间异质性显著;③ 两种供给服务（产水量与农作物生产）呈负相关的权衡关系,两种调节服务（碳储量与土壤保持）呈正相关的协同关系,不同的供给和调节服务之间关系既有权衡也有协同关系;④ 数值关系上,不同生态系统服务之间的权衡/协同关系在Moran's I和相关系数上表现不一;空间格局上,生态系统服务间的权衡/协同关系异质性显著。

Change and tradeoffs-synergies analysis on watershed ecosystem services: A case study of Bailongjiang Watershed,Gansu

Bailongjiang watershed in Gansu belongs to the upper reaches of Yangtze River water conservation area and the environment fragile area with frequent landslides and debris flow. Recently, the high-intensive human activities have caused the deterioration of natural systems. Therefore, it is of great significance to study the changes of ecosystem services and its trade-offs. In this paper, the spatial and temporal changes, spatial aggregation and the trade-offs/synergies between ecosystem services from 1990 to 2014 were quantitatively analyzed via the ecosystem service change index, spatial autocorrelation and correlation coefficient. The results showed that the ESCI ranges of the four typical ecosystem services types, namely, water yield, carbon storage, soil conservation and crop production were different from 1990 to 2014 with the difference of spatial distribution. There are spatial autocorrelation in four typical ecosystem services with obvious clustering characteristics. The cluster character and agglomeration of positive correlation of the local scale is strong, the agglomeration of the negative correlation type is low and scattered, and the spatial heterogeneity is significant. There is a negative correlation trade-offs between the two provisioning services (water yield and crop production), and positive correlation synergies between the two regulating services (carbon stocks and soil conservation). The relationships between the provisioning and regulating services have both trade-offs and synergies. There were both strong positive correlation synergies between water yield and soil conservation, and between water yield and carbon storage, and there were weak negative correlation trade-offs between soil conservation and crop production. As for the numerical relation, the trade-offs/synergies of ecosystem service changed differently in terms of Moran's I and correlation coefficient. There is significant heterogeneity of trade-offs/synergies between ecosystem services on the spatial pattern.