三峡库区蓄水前后土地利用变化对生态系统服务价值的影响

随着三峡库区蓄水完成以及城镇化进程的推进，土地利用结构发生了明显变化，其相应的生态系统服务价值也发生了改变。研究以三峡库区2000年、2007年和2014年三期的TM影像数据为数据源，利用RS和GIS技术，提取各期土地利用现状图，分析了三峡库区各期土地利用类型的数量、变化状态、转移趋势以及土地利用动态度、土地利用程度的变化特征，研究了三峡库区蓄水完成前后土地利用变化对生态系统服务价值的影响，最后利用敏感性指数模型验证结果的准确性。结果表明:2000—2014年三峡库区总体上呈现耕地、草地、林地和未利用地面积减少，建设用地、水域面积增加的趋势；建设用地和水域土地利用动态度较大，草地、耕地和林地动态度较小；2000—2014年三峡库区生态系统服务价值总体上呈现减少的趋势，14 a间减少了0.63亿元；三峡库区所有土地利用类型的敏感性指数均小于1，生态系统服务价值对生态价值系数缺乏弹性，结果可信。研究结果有助于了解近14 a来三峡库区的土地利用变化特征，从而为三峡库区土地利用的结构调整和环境保护提供参考。

Effect of Land Use Change on Ecosystem Service Value Pre and Post the Water Storage in the Three Gorges Reservoir Area

With the completion of water storage and the progress of urbanization in the Three Gorges Reservoir Area, the land use structure has changed significantly, and the corresponding ecosystem service value has changed. Taking three periods TM images of the Three Gorges Reservoir Area as the data source, this paper uses the RS and GIS technology to extract the land use map of each period, analyze the quantity, change state, transfer tendency of the type of land use and the characteristics of land use degree, study the effect of land use change on ecosystem service value pre and post the water storage in the Three Gorges Reservoir Area. The accuracy of the results is verified by the sensitivity index model in the study. The results indicate that the quantity of cultivated land, grass land, forest land, unused land decreased and construction land, water area increased from 2000 to 2014. At the same time, the land use dynamic degree were different of each land class, construction land and water area dynamic degree were high, while the grass land, cultivated land and forest land dynamic degree were very low. During 2000—2014, the value of ecosystem services in Three Gorges Reservoir Area shows a trend of decreasing, the ecosystem service value have increased 0.63 billion yuan. All of the land use sensitivity index are less than 1. The value of ecosystem services in the study area lack of flexibility on the ecological value coefficient. The results are credible. Research results are helpful to understand the characteristics of land use changes in recent 13 years, and the results could provide reference value for the adjustment of land use structure and environmental protection in the Three Gorges Reservoir area.