南水北调中线工程河南省受水城市地下水生态系统服务价值评估

Evaluation of groundwater ecosystem service value in Henan Province under the Middle Route of South-to-North Water Transfers Project

选取南水北调中线工程河南省受水城市为典型研究区域,综合运用市场价值法、替代工程法和等效替代法等对南水北调中线工程河南省受水城市2008—2019年地下水生态系统服务价值进行评估。结果表明:河南省11个受水城市中,地下水生态系统服务价值最高的是郑州市,变化较为稳定的是平顶山市、漯河市和许昌市,变化最剧烈的是鹤壁市。郑州市2019年地下水生态系统服务价值为213.17亿元,其中,调节服务价值最高,支持服务和供给服务价值次之,社会服务价值最低;在各指标中水源涵养指标占总价值比例最高,预防地面沉降指标次之,科研教育指标占比最小。河南省受水城市2008—2019年多年平均生态系统服务价值为1030.37亿元,变化趋势为先下降后上升,转折点出现在2013年,原因是地下水压采、南水北调中线工程置换地下水、植树造林、水土保持等措施增加了地下水资源量。研究结果可为南水北调中线工程受水城市生态环境效益评价及地下水保护提供参考依据。

As a national major strategic foundation project,the Middle Route of South-to-North Water Transfers Project not only plays a significant social and economic benefits,but also plays a huge ecological and environmental benefits.Although the economic and social benefits of the Middle Route of South-to-North Water Transfers Project are obvious,there is still a lack of systematic understanding and objective and accurate quantitative evaluation of its ecological and environmental benefits and its added value.Since the Middle Route of South-to-North Water Transfers Project was opened,the water source structure of the water-receieving cities has changed significantly,the exploitation of groundwater resources has decreased significantly,and the groundwater level has risen,which has significantly changed the ecosystem services of groundwater.In this context,it is of great significance to accurately and quantitatively assess the change of groundwater ecosystem service value in the water-receiving area before and after the Middle Route of South-to-North Water Transfers Project and to correctly understand the ecological and environmental benefits brought by the project and promote the rational and scientific utilization of the water resources of the project.The service value of groundwater ecosystem refers to the value that groundwater ecosystem provides material,energy and service to human society through various ways.According to the role of ecosystem in human survival and social and economic development,the value of ecosystem services is divided into four categories:product supply,support,regulation and cultural services.At home and abroad,the quantitative evaluation of ecosystem services mainly adopts three methods,namely,the quality evaluation method,the value evaluation method and the energy evaluation method.Based on the characteristics of the Middle Route of South-to-North Water Transfers Project and the water-receiving cities,the value assessment methods,including market value method,alternative cost method and mining loss method are adopted.The water-receiving cities in Henan Province under the Middle Route of South-to-North Water Transfers Project were selected as the typical research area,and the market value method,alternative engineering method and equivalent substitution method were used to evaluate the groundwater ecosystem service value of the cities in Henan Province from 2008 to 2019.The results showed that:(1)Among the 11 water-receiving cities in Henan Province,the highest value of groundwater ecosystem service was found in Zhengzhou City,the most stable changes were found in Pingdingshan City,Luohe City and Xuchang City,and the most drastic changes were found in Hebi City.(2)In 2019,the value of groundwater ecosystem services in Zhengzhou was 21.317 billion yuan,with the highest value of regulation services,followed by support services and supply services,and the lowest social services.Water conservation index accounted for the highest proportion of total value,followed by prevention of land subsidence index,and scientific research and education index accounted for the smallest proportion.(3)The annual average ecosystem service value of water-receiving cities in Henan Province from 2008 to 2019 was 103.037 billion yuan,and the change trend was first decreasing and then increasing.The turning point appeared in 2013,due to the increase of groundwater resources by underground water pressure extraction,groundwater replacement by the Middle Route of South-to-North Water Transfers Project,afforestation and soil and water conservation measures.The research results can provide a reference for the evaluation of eco-environmental benefits and groundwater protection of the Middle Route of South-to-North Water Transfers Project.