水库湿地作为北京市面积最大的人工湿地,是北京市重要的生态基础设施。从自然环境和社会经济因素两个方面,构建北京市水库湿地演变的驱动因子指标体系,其中自然驱动因子包括年均降水量、气温、入境水量和地下水埋深;社会经济驱动因子包括常住人口数、城市化率和人均GDP。应用长时间序列(1984-2010年)的TM遥感影像,提取北京市近30年来水库湿地的空间分布信息,根据湿地面积增长和消退的演变规律,利用Logistic回归模型定量分析不同时间段下水库湿地演变的驱动机制。结果表明:不同时期内水库湿地变化的驱动因子及其影响力存在一定的差异。在1984-1998年间,北京市水库湿地增长变化的主导驱动因子是年均降水量和入境水量,Logistic回归的贡献率分别为5.778和3.504,主要受自然环境因素的影响;在1998-2004年期间,水库湿地急剧减少的驱动因子主要为常住人口、地下水埋深和城市化率,影响贡献率分别为9.41、9.18和7.77,人为活动的影响开始加剧;在2004-2010年间,影响水库湿地发生变化的主导因子是城市化率和年均降水量,贡献率分别为6.62和4.22,受自然和社会经济因素的交叉影响。
The reservoir wetland of Beijing,constitutes one of the important eco-systems in Beijing.The driving factors index system of Beijing reservoir wetland landscape evolution in the study area was built in the two aspects of the natural environment and socio-economy.Natural driving factors include precipitation,temperature,entry water and groundwater depth;social economic driving factors include the resident population,urbanization rate and per capita GDP.Using TM images from 1984 to 2010 to extract reservoir wetland's spatial distribution information of Beijing,we analyzed the area of reservoir wetland change laws in nearly 30 years.The driving mechanism of reservoir wetland evolution in the study area was explored by the Logistic regression model in different periods.The results indicated that in different phases,the driving factors and their influence on reservoir wetland evolution had certain differences.During 1984-1998,the leading driving factors were annual average precipitation and entry water index with the contribution rate of Logistic regression being 5.78 and 3.50,respectively,which was mainly affected by natural environmental factors;from 1998 to 2004,the impact of human activities intensified and man-made reservoir wetland reduced,and the main driving factors were the number of residents,groundwater depth and urbanization rate with the contribution rate of Logistic regression 9.41,9.18,and 7.77,respectively.During 2004-2010,reservoir wetland evolution was impacted by both natural and socio-economic factors,and the dominant driving factors were urbanization rate and precipitation with the contribution rate of 6.62 and 4.22,respectively.