基于TM的重庆都市区土壤湿度时空变化研究

Study on the Temporal and Spatial Variation of Soil Moisture in Chongqing Based on TM

随着城市快速化发展,土地利用结构的变化,土壤湿度也随之发生变化,其作为生态环境研究的重要指标以及对农业发展有着重要作用,因此对其进行研究意义重大。文章选取1988 a、2000 a和2010 a的3期Landsat TM遥感数据和重庆都市区1:5万DEM数据,提取土壤湿度并对其在1988~2010 a间的数量、时间、空间上的变化进行分析。研究结果表明:1988~2010 a间,重庆都市区土壤湿度发生明显变化,其主要表现为低土壤湿度级区域面积增加,高土壤湿度级面积减少的趋势;其土壤湿度的变化特征体现出明显的规律性、阶段性以及地域性,而且其变化受建设用地扩展、土地利用结构的变化以及人为活动影响极其突出。研究结果旨在为城市的发展、生态环境保护以及农业的发展布局提供科学依据及参考。

Land use structure and soil moisture changed with the rapid development of city. As one of the indices of the ecological environment study, soil moisture played an important role for agricultural development. The objectives of this research were to use Landsat TM remote sensing data in 1988, 2000 and 2010 years and DEM data on a scale of1: 50000 of Chongqing area to extract soil moisture; and then to analyze the changes of soil moisture quantity, time and space during 1988-2010. The results showed that significant change of soil moisture was found in Chongqing in1988-2010. The area of low soil moisture level increased and the high soil moisture level decreased. The variation characteristics of the soil moisture reflected its obvious regularity, stage and regionality and were strongly affected by the expansion of construction, the changes of land use structure, and human activities. These results would provide scientific basis and reference for the development of city, the protection of ecological environment, and the development layout of agriculture.