基于易地扶贫搬迁视角的喀斯特生态脆弱区生态系统服务价值的时空演变

Spatial-temporal evolution research of ecosystem service value in ecologically vulnerable karst regions under the perspective of poverty alleviation relocation

易地扶贫搬迁是针对生活在“一方水土养不好一方人”地区贫困人口实施的一项专项扶贫工程,在助力贫困人口实现脱贫的同时,对改善生态脆弱区生态环境具有积极的促进意义。“十三五”期间贵州省易地扶贫搬迁人口约占全国总搬迁人口的1/5,是全国易地扶贫搬迁人口最多的省份,因此,研究选择贵州省县域搬迁人口最多的册亨县为研究区域。基于2009、2015、2020年3期土地利用和易地扶贫搬迁人口数据,研究选用修正当量因子法及耦合协调模型分析易地扶贫搬迁实施前后的生态系统服务价值(ESV)时空演变规律,并探讨了易地扶贫搬迁生态修复成效。结果表明:(1)搬迁后2015—2020年,册亨县ESV增长8.32亿元,增长幅度达到17.97%,比较搬迁前2010—2015年(增幅4.13%)有显著提高。(2)坡妹、冗渡、巧马、丫他、八渡、百口6个乡镇ESV增量占册亨县总增量的82.89%,ESV增量贡献最大。(3)册亨县搬迁力度越大的乡镇其ESV增加越明显,对应的耦合协调水平越高,易地扶贫搬迁与ESV增长有明显的空间相关关系。研究从生态系统服务的角度量化易地扶贫搬迁所产生的生态修复成效,有助于提高易地扶贫搬迁后续工作的科学性和空间针对性。

The poverty alleviation relocation is a special poverty alleviation project for the poor people who live in the regions with bad soil and water conditions which can′t afford to their lifestyle. The project is not only possible for poor people to get rid of poverty, but it also contributes to improve the ecological environment in the ecologically fragile regions. During the 13 th Five-Year Plan period of China, the population relocated from inhospitable areas in Guizhou province accounted for about 1/5 of the total population in China. As a result, Guizhou province has the largest population of under relocated people from inhospitable regions in China.Thus, this study takes a county with the largest relocated population in Guizhou province as an example. Based on land used maps in 2009, 2015 and 2020 years and spatial data of poverty relocated population, a modified equivalent factor method and a coupling coordination model were used to explore the relocation of the largest population in Ceheng County, Guizhou Province. Meanwhile, the Spatial-temporal evolution of ecosystem service value(ESV) with the implementation of the policies for poverty-alleviating relocation out of inhospitable regions and its intrinsic laws were analyzed, and then the effectiveness of poverty alleviation relocation for ecological restoration were explored. The experimental results show that:(1) From 2015 to 2020 after the project implementation, the ESV has a significant improvement, which is increased by RMB 832 million yuan at a rate of 17.97%, more than 4 times that from 2010 to 2015 before the implementation of the project at a rate of 4.13%;and(2) In the study area, the growth of ESV of the six towns of Pomei, Sandu, Qiaoma, Yata, Badu and Baikou accounts for 82.89% of the total increment of the study area, which is the largest contribution of the ESV increment;and(3) There was an obvious spatial correlation between the poverty-alleviating relocation out of inhospitable regions and the growth of ESV, and the coupling coordination degree between the ESV variable and the relocated population′s density in this study area was significant association. The larger the relocation of the townships in the county, the more obvious the increase of ESV. From the perspective of ecosystem services, this study quantifies the effects of ecological restoration triggered by the poverty-alleviating relocation out of inhospitable regions. The results of this study are helpful for improving the scientific and spatial pertinence of the corresponding follow-up work.