基于空间信息技术的巫山县土地利用时空变化分析

AN ANALYSIS ON SPACE-TEMPORAL VARIATION OF LANDUSE IN WUSHAN COUNTY BASED ON SPACE INFORMATION TECHNOLOGIES

巫山县位于三峡库区腹心 ,又地处山区 ,县境虽然辽阔 ,但山多坝少 ,且农业人口比例很高 ,因此土地资源十分有限。近十几年来 ,三峡工程的兴建 ,导致移民搬迁、城镇迁建及伴随工程的基础设施的建设等占用大量优质土地。迫于生计 ,部分农民不得不毁林开荒造田 ,坡耕地因此而增多 ,继而造成水土流失加剧 ,土壤日趋贫瘠 ,最终导致该县土地利用类型、数量、方式发生了急剧的变化。以空间信息技术为研究手段和技术支持 ,首先从理论角度探讨了山区土地利用时空变化的研究方法 ;然后以典型山区县城———巫山县为例 ,以该县 1986～ 2 0 0 0年的TM图像数据为主要研究基础 ,采用地理信息系统软件和计算机技术相结合的方式分析了这个山区县城 15年来土地利用变化的特点和规律 ,并结合当时当地的各种自然、人文和社会环境等驱动因子 ,进一步详细地分析了各种主要土地利用类型的具体原因。旨在为当地政府或管理部门提供土地资源合理开发、利用和正确管理的理论依据和科学方法 。

Being located in the mountainous area and the center of the Three Gorges' Reservoir Area. Wushan County is an extensive region, but has more mountains than plains and higher ratio of peasants,so the resources of land are very limited.Especially in recent years, the construction of the Three Gorges' Project,which has caused emigration,the relocation of city and building of based installations have to be accompanied with the project.All these projects have used large quantity of high quality land. Some peasants,in order to live,had to destroy forests,open up wasteland,increase the area of slope land,resulting in exacerbation of soil erosion and increasing leanness of soil.In this paper, space information technologies are considered as the means of research and technological support.Then taking Wushan County as an representative county of mountainous area,we selected the TM images from year 1986 to 2000 as the main research base and used the combined methods of Geographic Information System software and computer technology,analysed the characteristics and laws of the landuse change of the county over 15 years.Finally we discussed the essential reason of the main landuse type change according to the natural and social factors.The intend is to provide the theoretic basis and scientific methods for rational development,and for the management of land resources.At the same time,the article also provides methods to use for reference in the space temporal variation of landuse in mountatainous area.