沙漠生态系统服务价值评估——以乌兰布和沙漠为例

Dynamics of Ecosystem Service Value in Ulan Buh Desert in the Past 30 Years

本研究基于RUSLE和InVEST模型核算研究区生态系统服务土壤保持量、水源涵养量等实物量,综合运用影子工程法、替代成本法、市场价格法等生态经济学方法,定量评估乌兰布和沙漠1990-2018年食物与原材料供给、植被固碳释氧、水源涵养等12项生态系统服务价值及其动态。结果表明:1990-2018年研究区生态系统服务价值呈先下降后上升的趋势,2018年价值量最高,达139.62亿元,其中调节服务和支持服务对总服务价值贡献最大,占90%以上;各土地利用类型对总价值的贡献率从1990年到2018年变化显著,流动沙丘贡献率由79.65%降至26.04%,固定沙丘贡献率由2.31%增加至39.75%,且价值流动增加;研究期间调节服务、支持服务占比逐期下降,供给服务和文化服务价值占比逐期上升;支持服务与其他服务间呈权衡关系。通过本研究为沙漠生态系统资源合理利用及区域社会可持续发展提供科学依据。

Using the RUSLE and InVEST models, this study calculated the physical quantities of soil conservation and water retention services in Ulan Buh Desert.The value of 12 ecosystem services, including product provisioning, carbon fixation, oxygen release, water balance regulation, water retention, soil fertility conservation, sediment deposition reduction, transportation loss reduction, biodiversity conservation, tourism and entertainment culture services, were measured from 1990 to 2018 by the methods of shadow-price, market-price, and alternative cost.The results indicated that the ecosystem service value of the study area decreased first and then increased from 1990 to 2018.The ecosystem service value in 2018 was the highest, reaching 13.962 billion yuan.Regulation services and support services contributed the most, accounting for more than 90%.The contribution rate of each land use type to the total ecosystem service value changed significantly from 1990 to 2018.The contribution rate of mobile dunes decreased from 79.65% to 26.04%,and that of fixed dunes increased from 2.31% to 39.75%.During the study period, the proportion of regulatory services and support services decreased gradually, while the proportion of supply services and cultural services increased gradually.There was a trade-off between support services and other services.This study can provide scientific evidences for rational utilization of desert ecosystem resources and sustainable development of regional society.