呼包鄂榆城市群生态系统服务价值驱动因素及其交互效应

Driving factors and their interaction effects of ecosystem service value in the Hohhot⁃Baotou⁃Ordos⁃Yulin urban agglomeration

增强呼包鄂榆城市群生态系统服务功能,对于推动黄河流域生态保护和高质量发展具有重要意义。基于研究区1990—2020年土地利用类型评价了生态系统服务价值(ESV),耦合随机森林模型与沙普利加性解释(SHAP)方法分析ESV驱动因素的重要程度、变化响应特征及其交互效应,采用偏最小二乘路径模型识别驱动因素的交互路径。结果表明:(1)研究期内耕地、草地和水域面积整体呈先增后减趋势,建设用地面积持续增加;ESV呈先减后增趋势且总体增加了62.28亿元,ESV的增长主要是林地向耕地和草地扩张的结果。(2)最主要的ESV驱动因素为土地利用类型,其贡献度达到61.24%,其次是地形和气象,贡献度分别为17.59%和17.05%,社会经济的贡献度最低,仅为1.73%;ESV对驱动因素的响应呈非线性变化特征。(3)水域比例是最重要的交互项,交互作用在因素处于不同范围内表现出不同的交互效应。土地利用直接影响ESV,而地形、气象、土壤和社会经济因素主要通过影响土地利用进而间接影响ESV,社会经济因素对ESV的直接和间接影响分别是负和正效应。研究建议通过完善城市群国土空间规划,重点加强草地、林地和水域等生态空间保护并协调好与城镇建设、矿产资源开发的关系,以提升生态系统服务功能为导向实施区域生态系统多因素协同管控。

The enhancement of ecosystem function within the Hohhot-Baotou-Ordos-Yulin urban agglomeration is significant for advancing ecological protection and promoting high-quality development in the Yellow River basin.Ecosystem service value(ESV)was evaluated based on the land use types in the study area from 1990 to 2020,the random forest model coupled with the SHAP method were used to analyze the importance,response,and interaction of the driving factors,and partial least squares path modeling was used to identify interaction paths of the driving factors.The results showed that(1)the area of cropland,grassland,and water exhibited an initial increase followed by a decrease,while the construction land area continued to increase.The ESV underwent an initial decline,followed by an increase of 62.28 billion yuan,primarily due to the conversion of cropland and grassland to forest.(2)Land use was the most important driving factor of ESV change,with a 61.24%contribution rate.Natural factors,including topography and meteorology,were the next significant contributors,with 17.59%and 17.05%contribution rates,respectively.Socio-economics factors had the least impact on ESV,with only 1.73%contribution rate.The responses of ESV to driving factors were characterized by nonlinear changes.(3)The proportion of water was the most important interaction factor,and the interaction between driving factors showed different effects when the driving factors were in different ranges.Topography,meteorology,soil,and socio-economics indirectly influenced ESV by affecting land use.The direct effects of socio-economics on ESV were negative,while its indirect effects were positive.It recommended to strengthen the protection of grassland,forest,water,and other ecological spaces and further to coordinate their relationship with urban construction and mineral resource development.Furthermore,the implementation of multi-factor collaborative management and control of regional ecosystems was oriented towards improving service functions.