白洋淀流域土地覆被变化及其生态服务价值评价

摘要

白洋淀流域处于京津腹地, 经济、生态战略地位显要, 研究其土地覆被变化规律及它引起的生态系统服务价值变化具有重要意义.文章研究了白洋淀流域2005-2015年土地覆被的变化情况, 并对其引起的生态系统服务价值的变化进行分析.为此, 收集了该区域2005年、2015年两个时间段TM/OLI遥感影像, 解译出相应的土地覆被数据, 从两个时期土地覆被变化的趋势、转换关系及土地利用程度等方面对土地覆被变化规律进行分析, 并进一步分析不同土地覆被类型变化对当地生态服务价值的影响.结果表明:2005—2015年间流域内土地覆被显著变化, 草地、未利用地的面积呈减少趋势, 林地、耕地、建设用地、湿地水体呈增加趋势, 土地利用程度增加;生态服务价值随土地覆被变化有所改变, 林地、耕地、湿地水体的变化导致生态服务价值增加, 草地的变化导致生态服务价值减少.总体而言, 近10年来白洋淀流域生态服务总价值增加, 生态环境明显改善.%Baiyangdian watershed is located in the hinterland of Beijing and Tianjin.Its economic and ecological status is very important to this region.Thus, it is very important to study the discipline of land cover change and its impact on ecosystem service.The study analyzed the changes of land cover in the Baiyangdian watershed during year 2005 to 2015 and the corresponding ecosystem service change.For this purpose, the TM/OLI images in year 2005 and 2015 were collected, and then they were used to identify the land cover type in each year.The above land cover data from two periods were analyzed for the trend of changes, relationship of mutual conversion, and extends of land usage.Furthermore, the impact of land cover change on the ecological service was also analyzed.The results showed that the land cover was significantly changed from 2005 to 2015, with the area of grassland and unused land decreasing and the area of forest land, cultivated land, construction land and wetland increasing.The total land use degree was increased.The value of ecological service was changed with the change of land cover.The change of forest land, farmland and wetland caused ecological service increasing, while the change of grassland led to ecological services decreasing.Overall, in recent decades, the total value of ecological service in Baiyangdian watershed was increased, resulting in significantly improvement of ecological environment.