基于LUCC的汤浦水库流域生态价值变化过程研究

Change Process of Ecological Value of Tangpu Reservoir Basin Based on LUCC

[目的]探究水库开发建设及管理活动对汤浦水库流域土地利用及生态环境效应的影响,为水源地水库污染防治及运行管理提供参考。[方法]通过ENVI遥感解译水库流域从建库前至今5个不同时期的土地利用状况,分析水库流域LUCC转移矩阵和生态价值指数,并基于ArcGIS空间分析,对流域内主要污染监测控制区进行识别,同时对水库流域内现有居民搬迁后流域生态价值指数变化趋势进行预测。[结果]流域主要LUCC表现为林地—草地—林地;近20 a流域生态价值指数呈N字形趋势,在2008年达到最高,流域中部山地林区的生态价值指数高于其他区域且生态价值较为稳定;流域重点监控区应设在沿S212省道东西走向一段及王坛镇区域;逐步实施流域生态搬迁以后,流域相对生态价值指数上升趋势先慢后快。搬迁地的生态价值指数由0.015增加至0.081,相应的,全流域的生态价值指数提高11.2%。[结论]水库流域近20 a生态环境保护良好,退耕还林工程的实施以及人类活动是影响水源地水库保护区生境质量变化的主要原因。

[Objective]The impacts of Tangpu reservoir development and management activities on watershed land use and eco-environmental effects were studied in order to provide reference for pollution prevention and operation management of water source reservoirs.[Methods]Through ENVI remote sensing interpretation of the land use status of the reservoir basin in five different periods,the LUCC transfer matrix and ecological value index of the reservoir basin were analyzed.Based on the spatial analysis of ArcGIS,the main pollution monitoring and control areas in the basin were identified,and the trend of the ecological value index of the basin after the relocation of existing residents in the reservoir basin was predicted.[Results]The main LUCC in the basin was forest land-grassland-forest land;the ecological value index of the basin in the past 20 years showed an“N”shape trend,which reached the highest in 2008;The ecological value index of mountainous forest areas in the basin was higher than other areas and the ecological value was relatively stable;The key monitoring area of the basin should be located along the east-west section of the S212 provincial road and the area of Wangtan Town,after the implementation of the ecological resettlement of the basin,the relative ecological value index of the basin would increase slowly then quickly.The ecological value index of relocation increased from 0.015 to 0.084 and the ratio of whole basin increased 11.2%.[Conclusion]The reservoir had been in good ecological environment for nearly 20 years.The implementation of the project of returning farmland to forests and human activities were the main reasons affecting the changes in habitat quality of reservoirs in water source areas.