青藏高原生态系统服务供需变化及其驱动因素

Changes and driving factors of ecosystem services supply and demand on the Tibetan plateau

准确识别生态系统服务供给与需求的空间特征和空间匹配,确定影响供需关系的因素,对指导区域生态系统管理和恢复具有重要意义。采用修正通用土壤流失方程(RUSLE)、生态系统服务和权衡综合评估模型(InVEST)和卡内基-艾姆斯-斯坦福模型(CASA)等多种模型方法探讨青藏高原土壤保持、产水和碳固定服务的供给与需求的时空特征,并结合冗余分析,进一步识别青藏高原生态系统服务供给、需求与供需比的影响因素。结果表明:(1)2000-2018年青藏高原土壤保持、产水和碳固定服务的供给量,以及产水和碳固定服务的需求量均呈现增加趋势,供给量分别增加30.57t、63.61×10^(4)m^(3)、33.81t,需求量分别增加153.42m^(3)和5.09t,而土壤保持服务需求量呈减少趋势,减少16.39t。(2)青藏高原各项生态系统服务供需匹配状况不同,碳固定服务供需比呈下降趋势,产水服务供需比呈上升趋势,土壤保持服务供需比波动变化,总体呈上升趋势,局部呈下降趋势。(3)各项生态系统服务供需关系均以低低型空间匹配为主。(4)降水和坡度是影响生态系统服务供给的主要因素,生态系统服务需求主要受人口密度和国内生产总值的影响,降水和温度是影响生态系统服务供需比的关键因素。研究评估青藏高原生态系统服务供给与需求之间的关系,以及明确供需关系的空间显性驱动力,为区域的生态系统综合管理提供依据。

For directing regional ecosystem management and restoration,it is crucial to accurately define the spatial characteristics and spatial matching of ecosystem service supply and demand,as well as the variables affecting the link between supply and demand.In order to explore the spatial and temporal characteristics of supply and demand for soil conservation,water yield,and net primary production on the Tibetan Plateau,various modeling approaches including Revised Universal Soil Loss Equation(RUSLE),Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST),and Carnegie-Ames-Stanford Approach(CASA)were used in this study.Redundancy analysis was also used to further identify the factors influencing supply,demand,and the supply-demand ratio of ecosystem services on the Tibetan Plateau.The results showed that(1)on the Tibetan Plateau,the supply of services related to soil conservation,water yield,and net primary production,as well as the demand for these services,all showed an upward trend from 2000 to 2018;the supply increased by 30.57t,63.61×10^(4)m^(3),33.81t,and the demand increased by 153.42m^(3) and 5.09 t,respectively.(2)The supply-demand ratio of various ecosystem services varied,with the ratio of services related to net primary production showing a decreasing trend,the ratio of services related to water yield showing an increasing trend,and the ratio of services related to soil conservation fluctuating between an overall increasing trend and a local decreasing trend.(3)All supply and demand connections for ecosystem services were dominated by low-low type geographic matching zones.(4)The primary determinants of ecosystem service supply were precipitation and slope,while the primary determinants of ecosystem service demand were population density and gross domestic product,and the primary determinants of ecosystem service ratio were precipitation and temperature.In order to lay the groundwork for integrated ecosystem management in the area,this study evaluated the relationship between supply and demand for ecosystem services on the Tibetan Plateau and defined the spatially explicit drivers of supply and demand.