治沟造地背景下延安市土地利用与生态系统服务价值变化

Changes of land use and ecosystem service value in Yan'an City under the background of gully control and land consolidation project

治沟造地是延安市实施的一项增加耕地面积、保障粮食安全、保护生态环境的重大生态环境治理工程。研究治沟造地工程背景下延安市土地利用及生态系统服务价值变化,对科学评价治沟造地工程生态效益及黄土高原生态保护和高质量发展具有重要意义。基于2010、2018年Landsat TM/OLI遥感影像,运用单位面积价值当量因子法,定量分析了延安市2010—2018年土地利用及生态系统服务价值变化特征。结果表明:延安市主要土地利用类型为草地、林地和耕地,研究期内延安市土地利用类型变化主要为三者互相转化,变化幅度不大,维持在比较稳定的状态;延安市生态系统服务价值从2010年的955.91亿元增加到2018年的958.56亿元,增幅为0.28%,草地和林地为生态系统服务价值贡献最大;疏林地、高覆盖草地和水域是生态系统服务价值变化的主要贡献因子和敏感因子;延安市各项生态系统服务功能中,调节服务是最重要的功能,其中气候调节价值最大,研究时段所有单项生态系统服务价值变化幅度均小于1%。

The gully control and land consolidation project is a major ecological environment management project implemented by Yan'an City for increasing the area of cultivated land,ensuring food security,and protecting the ecological environment.A study on the change of land use and ecosystem service value in Yan'an City underlying this project has important implications for scientific assessment of ecological benefits of this project as well as ecological protection and high quality development of the Loess Plateau.Based on the Landsat TM/OLI images in 2010 and 2018,the unit area value equivalent factor method was employed to quantitatively analyze the variation of land use and ecosystem service value in Yan'an City from 2010 to 2018.Results showed that the land use types in Yan'an City mainly included grassland,forest land,and cultivated land.During the study period,the land use types remained relatively stable with limited interchangeable transformation among cultivated land,forest land,and grassland.The ecosystem service value of Yan'an City increased by 0.28%from 95.591 billion yuan in 2010 to 95.856 billion yuan in 2018.Grassland and forest land were the key factors contributing to ecosystem service value.Sparse forest land,high covered grassland and water area were the main contributing factors and sensitive factors of ecosystem service value change.The regulation service was the most important of all the ecosystem service functions in Yan'an City,among which the climate regulation had the greatest value.The range of variation for the value of each ecosystem service was<1%.