2000-2020年山西省宁武县生态系统服务价值时空动态研究

Spatiotemporal Dynamics of Ecosystem Service Value in Ningwu County,Shanxi Province from 2000 to 2020

生态系统服务价值(ESV)时空动态研究对生态修复工程的评价、生态修复空间的准确识别和生态安全格局建设具有重要意义。收集宁武县2000-2020年5期的土地覆被类型数据,应用价值当量因子法量化ESV,运用网格分析法、热点分析法研究其时空变化规律,同时运用相关性分析法分析ESV变化影响因素。结果表明:(1)宁武县近20 a年均ESV为169032.41万元,2000-2020年ESV增加了5.80%;5期ESV总体呈现先下降后上升波动变化,2020年4个一级生态服务功能指标都有增加,比例为调节服务(20.23%)>文化服务(18.63%)>支持服务(18.36%)>供给服务(14.56%);(2)14个乡镇5期ESV空间分布较为一致,呈聚集型,高值集中分布在县域西部和东北部山区,低值分布在县域中间的汾河及恢河流域;(3)2000-2020年,ESV变化的冷点区和热点区分别占研究区面积的10.14%和9.30%。冷点区主要分布在汾河流域和恢河流域中部,热点区分布在县域中部及东部,在生态修复中应予以重视。此外,热点区所占比例呈上升趋势,表明各类生态修复项目的生态功能逐步提升;(4)相关性分析表明,针叶林、灌木、灌草和湿地这4类土地覆被类型对提升宁武县ESV有重要意义,自然因素中坡度、高程、降水与ESV呈显著正相关。

The study on the spatiotemporal dynamics of ecosystem service value(ESV)is of great significance to the evaluation of ecological restoration projects,the accurate identification of ecological restoration space,and the construction of ecological security pattern.Ningwu County in Shanxi Province is not only the source of the Fenhe River,but also a typical coal resource county with an ecological rehabilitation experimental site.To investigate the spatiotemporal dynamics of ESV in Ningwu County,a study was conducted based on the land cover data(2000-2020).The ESV was quantified by the equivalent factor method.Moreover,the grid analysis method and hot spot analysis method were adopted to investigate the spatiotemporal evolution of ESV.The correlation analysis was conducted to assess the influencing factors of ESV.The main results were summarized as follows.(1)The average annual ESV of Ningwu county was 1690.3241 million yuan from 2000 to 2020.In comparison with the ESV in 2000,the ESV in 2020 increased by 5.80%.Overall the ESV declined at the first three phases,then rose at the last phase.Noticeably,the four primary service function indicators increased in 2020,and the proportions were in the order of regulation service(20.23%)>cultural service(18.63%)>supporting service(18.36%)>provisioning service(14.56%).(2)The similar clumped patterns of the total spatial distribution of ESV were observed in 14 townships with the highest values in the mountainous areas,and the lowest values in the watersheds of the Fenhe River and the Huihe River.(3)From 2000 to 2020,the cold spots and hot spots of ESV change accounted for 10.14%and 9.30%,respectively.Specifically,the cold spots were mainly distributed in the middle of the watersheds of the Fenhe River and the Huihe River,while the hot spots were distributed in the middle east of the county,which should be taken seriously during ecological rehabilitation.Moreover,the proportion of hot spots indicated a growing trend,indicating that the ecological functions of all kinds ecological rehabilitation projects gradually rose.(4)The correlation analysis indicated that coniferous forest,shrub,shrub and herb,and wetland were significant for elevating ESV in Ningwu County.Among the natural factors,slope,elevation and precipitation were significantly and positively correlated with ESV.