生态系统服务综合关系空间分异及驱动因素——以石羊河流域为例

Recognition of Ecosystem Services Trade-offs and Synergistic Comprehensive Relations——A Case Study of Shiyang River Basin

明晰区域多种生态系统服务之间的综合关系特征和驱动机制,是生态系统管理的前提,具有重要意义。利用气象、土地利用、NDVI、土壤等数据,基于InVEST模型、CASA模型和RUSLE模型,借助相关性分析方法对石羊河流域2003—2018年的产水、NPP和土壤保持服务及其权衡与协同关系进行定量计算和分析,提出多种生态系统服务间综合关系的识别方法,对石羊河流域生态系统服务综合关系空间分异特征进行研究,并采用地理探测器法揭示了其驱动机制。结果表明:(1) 2003—2018年,石羊河流域生态系统产水及土壤保持服务呈下降趋势、NPP呈上升趋势,石羊河流域生态系统产水服务和土壤保持服务以协同关系为主,产水服务和NPP,NPP和土壤保持服务以权衡关系为主;(2)石羊河流域生态系统服务综合关系具有明显的空间异质性,综合关系为全协同的区域主要分布在肃南县境内,综合关系为全权衡的区域主要分布在天祝县祁连镇以及民勤县的西渠镇、东湖镇和收成地区,综合关系为权衡主导的区域占石羊河流域面积比最大,为74.44%;(3)海拔高度是决定石羊河流域生态系统服务综合关系空间分异的主导因子,各子流域探测的主导因子存在差异性,且双因子交互作用对综合关系空间分异的解释力更强。综上,石羊河流域大部分地区生态系统服务之间仍是以权衡关系为主导,亟需通过生态系统管理来协调生态系统服务之间的关系;天祝县祁连镇以及民勤县的西渠镇、东湖镇和收成地区的生态问题需要重点和优先关注。

It is the premise of ecosystem management to clarify the characteristics and driving mechanism of the comprehensive relationship between various ecosystem services. In this paper, we used meteorological, land use, NDVI, soil and other data to quantitatively calculate and analyze water production, NPP and soil conservation services and their trade-offs and synergies in Shiyang River Basin from 2003 to 2018 based on InVEST model, CASA model and RUSLE model, with the help of correlation analysis method. Moreover, we proposed a method to identify the comprehensive relationship ecosystem services(CRES). Study on the spatial differentiation characteristics of the CRES in Shiyang River Basin, and the driving mechanism was revealed based on the geographic detector method. The results are shown as follows.(1) From 2003 to 2018, ecosystem water production and soil conservation services in Shiyang River Basin showed a downward trend and NPP showed an upward trend. Ecosystem water production services and soil conservation services in Shiyang River Basin were mainly collaborative, and water production services and NPP, NPP and soil conservation services were mainly balanced.(2) The comprehensive relationship of ecosystem services in Shiyang River Basin had obvious spatial heterogeneity. The regions with comprehensive relationship dominated by full synergy mainly distributed in Su′nan County, and the regions with comprehensive relationship dominated by full trade-off mainly distributed in Qilian Town of Tianzhu County and Xiqu Town, Donghu Town and Shoucheng area of Minqin County. The regions with comprehensive relationship dominated by trade-off account for the largest proportion of Shiyang River Basin, with the value of 74.44%.(3) Altitude was the leading factor to determine the spatial differentiation of CRES in Shiyang River Basin, there were differences in the main factors of sub watershed detection, the interaction of two factors was more powerful in explaining the spatial differentiation of CRES. To sum up, most areas of the Shiyang River Basin are still dominated by trade-offs, and it is urgent to coordinate the relationship between ecosystem services through ecosystem management. The ecological problems of Qilian Town in Tianzhu County, Xiqu Town, Donghu Town and Shoucheng area in Minqin County need to be focused and prioritized.