2000年以来张家口坝上高原生态系统服务价值及其变化

Ecosystem Service Values and Their Changes of Bashang Plateau, Zhangjiakou since 2000

以河北省张家口市的张北县、康保县、沽源县和尚义县为研究区,利用2000年、2005年、2010年、2015年和2020 年的多时相 Landsat 遥感影像数据,获取研究区的土地利用信息,在 Google Earth Engine 平台上,估算研究区的植被覆盖度,采用当量因子法,估算研究区的生态系统服务价值;通过生态贡献率空间化和热点分析,探讨土地利用变化下研究区生态系统服务价值的时空变化;建立植被覆盖度贡献率指数,分析植被覆盖度变化对研究区生态系统服务价值的影响。研究结果表明,从2000年、2005年、2010年、2015年到2020年,随着时间的推移,研究区的稀疏林地面积在增大,耕地、沼泽、河流和湖泊的面积在减小,增加的稀疏林地主要由草地和耕地转化而来;总体上,研究区的植被覆盖度在增大;随着土地利用和植被覆盖度的变化,研究区的生态系统服务价值总体上呈增大趋势;2020 年研究区的生态系统服务价值为 206.93×10;元,比 2000 年增加了 18.16%;退耕还林、退耕还草是研究区生态系统服务价值增大和形成增值热点区的主要原因,湿地萎缩或丧失是部分区域生态系统服务价值减小和形成损失冷点区的主要原因;植被覆盖度对研究区生态系统服务价值的贡献率逐年增大;在退耕还林、退耕还草和湿地萎缩或丧失的多重影响下,张家口坝上高原生态系统依然脆弱,在未来张家口首都生态环境支撑区和水源涵养功能区的建设中,需要加强对张家口坝上高原湿地的保护和修复,巩固现有生态保护成果,促进区域可持续发展。

In this study, Zhangbei, Kangbao, Guyuan and Shangyi counties in Zhangjiakou city, Hebe province were as the study area, and land cover and land use maps in 2000, 2005, 2010, 2015 and 2020 were generated based on multi-temporal Landsat satellite images. The vegetation fractional coverage of the study area were estimated on the Google Earth Engine platform;and ecological service values of the study area were calculated using equivalent factor method. By spatial analysis of ecological contribution rate and ho spot analysis, the impact of land cover and land use changes on the temporal and spatial variations of ecological service values were discussed. Furthermore, the vegetation coverage contribution index to investigate the impact of vegetation coverage change on ecological service values was proposed. The results showed that the areas of sparse forest lands increased, and the areas of cultivated lands, marshes, rivers and lakes decreased in 2000, 2005, 2010, 2015 and 2020, as time goes on. The increased sparse forest lands were mainly converted from grasslands and cultivated lands. Overall, the vegetation coverage showed an upward trend. With land use and vegetation coverage changes, on the whole, the ecological service value of Bashang Plateau, Zhangjiakou was increasing since 2000. The ecological service value of Bashang Plateau Zhangjiakou in 2020 was 206.93×10;yuan, with an increase of 18.16% compared to that in 2000. Returning farmland to forest land was the main reason for the overall improvement of ecological service value and the formation of hot spots of ecological service value increase. Shrinkage or loss of the wetlands was the main reason for the decline of ecological service value and the cold spots of ecological service value loss. The contribution rate of vegetation coverage to ecological service value increased from 2000 to 2020. Under the dual influences of returning farmland to forest land or grassland and shrinkage or loss of the wetlands, the ecosystem of Bashang Plateau, Zhangjiakou is still fragile. To support the construction of ecologica environment support area and water conservation function area for the capital of China, it is necessary to strengthen wetland protection and restoration, consolidate the existing ecological achievements and promote regional sustainable development.