丹江口水源区生态系统服务时空变化及权衡协同关系

研究区域多种生态系统服务之间的权衡协同关系特征,对不同生态系统服务、不同区域之间的协调发展,实现利益相关方效益最大化,达到区域发展与生态保护"双赢"具有重要意义。针对目前权衡协同定性分析、长时间动态变化研究不足的现状,以丹江口水源区为例,在采用"当量因子法"求得研究区生态系统服务价值的基础上,使用长时间整体分析占优的相关性分析方法和短时期动态变化分析占优的生态系统服务权衡协同度(ESTD)模型对研究区1990—2015年10种生态系统服务的权衡协同关系展开研究。结果表明:1990—1995年,丹江口水源区生态系统服务价值呈负增长,之后则呈不断上涨的时序变化趋势,增幅最大的生态系统服务为水资源供给。生态服务价值最高的用地类型为林地,其次为草地和水域。空间上,生态系统服务价值呈东南高西北低特征。在丹江口水源区生态系统服务之间相互关系中,协同关系占64%,是丹江口水源区生态系统服务之间的主导关系,权衡关系较少,且大多存在于供给服务与调节服务、文化服务、支持服务之间。丹江口大坝加高后,即2005年之后,水源区内生态系统服务之间的权衡协同方向有所改变,改变明显的生态服务有净化环境、水文调节和水资源供给。这3种生态系统服务与生态系统服务之间的权衡关系增多,除这3种生态系统服务外,其余几种单项生态系统服务与生态系统服务之间的权衡关系减少。

Study on spatial-temporal change andtrade-off/synergy relationships of ecosystem services in the Danjiangkou water source area

Ecosystem management that attempts to maximize the production of one ecosystem service may result in substantial declines in the provision of other ecosystem services. For this reason, understanding the trade-offs and synergies of ecosystem services is of considerable significance to balance the characteristics of multiple ecosystem services and maximize the benefits of ecosystem services. The current situation is that there is insufficient researches on qualitative analysis and long time series of dynamic change among the trade-offs and synergies relationship. In addition, the selection of ecosystem services are inadequate. The Danjiangkou water source area is an important area of the South-to-North Water Diversion Project, and clarifying the temporal and spatial variation characteristics and relationships among ecosystem services can provide reference guidance for the smooth progress of the water transfer project in the middle route of the South to North Water Transfer project. At present, analysis of the relationships among ecosystem services in the Danjiangkou water source area is still insufficient. Given this situation, we studied the ecosystem service relationships of a long time series in the Danjiangkou water source area using different methods. First, we used the equivalent factor method to estimate the ecosystem service value. We then discuss the spatial-temporal difference and relationship of ecosystem services in six periods by correlation analysis and using an ecosystem services trade-off degree (ESTD) model. Correlation analysis has the advantage over long time series analysis. The ESTD model has the advantage of dynamic change analysis for short time periods. The results showed that during the period of 1990 to 1995, the value of ecosystem services in the Danjiangkou water source area showed a negative growth. However, the value of ecosystem services significantly improved from 1995 to 2015. The largest increase in ecosystem services occurred in water supply, and forest land provided the highest value of ecosystem services. Ecosystem service value increased from northeast to southwest. Correlation analysis showed that synergy is the dominate relationship among ecosystem services, and that there are few trade-offs in the Danjiangkou water source area. Since the Danjiangkou dam was heightened (after 2005), the relationship among ecosystem services in the water source area have changed. The trade-off relationships in the water source area increased among water supply, hydrological adjusting, and environment depuration, and trade-offs were reduced in other ecosystem services. Human disturbance is the most important factor that results in ecosystem service change.