地震前后都江堰市土地利用动态变化研究

都江堰市是世界自然和文化遗产所在地,是世界著名旅游城市,国家级历史文化名城.汶川特大地震,造成都江堰市全域性破坏,经济社会发展一度停滞,灾后恢复重建的2年是其社会经济发展的关键时期.运用GIS空间分析模型,以都江堰市1∶5万地形图、ETM+与Quickbird遥感影像为基础,对比分析了地震前后都江堰市土地利用类型变化幅度、变化速度、变化方向以及变化程度等特征.结果表明:都江堰市地震前(2004—2008年)耕地、园地与林地面积有所减少,建设用地、草地和未利用地面积均有增加,地震后(2008—2010)即震后恢复期,园地面积和建设用地面积大幅度增加;灾后重建两年土地利用变化速度达到1.69%,是地震前4年(0.62%)的近3倍;土地利用变化方向主要是其他地类向建设用地的转化;土地利用变化率震后达到0.5%,是震前4年(0.24%)的2倍多,说明都江堰市的土地利用一直处于发展期,特别是震后土地利用强度不断提高,人类活动对土地利用的影响不断加大.最后分别从自然、人口和经济等多个方面探讨了土地利用动态变化的驱动力并针对都江堰市土地利用面临的形势和主要问题,提出了土地利用布局统筹协调和整体控制的基本发展模式,对都江堰市的土地管理提供重要参考.

The Research of Land Use Dynamic Change before and after the Earthquake in Dujiangyan City

Dujiangyan,the world natural and cultural heritage,is a famous travel site of the world and a national historical and cultural city,which was destroyed seriously by Wenchuan Earthquake.The earthquake had a huge negative influence on the development of its economy for a long time.The following two-year-long post earthquake reconstruction is the key period for its further development.This paper mainly applies the special analysis methods of GIS,based on 1∶500 000 topographic map of Dujiangyan,ETM and Quickbird image data of research area,in order to analysis the characteristics of land use dynamic change before and after the earthquake in Dujiangyan,which includes the magnitude,the speed,the direction and the degree of the changes.The results show that cultivated land,forest and garden area have been reduced,but the building land,unused land and grassland have increased from 2004—2008 years before the earthquake.While garden area and building area have a substantial increase from 2008—2010 years.During the two years of reconstruction,the speed of land use change reaches 1.69 percent rate,which is as nearly three times as 4 years before the earthquake(0.62%).The direction of land use change mainly transforms from other land to building land.The rate of Land use change was 0.24% per year before the earthquake,while after the earthquake it reached 0.5%,which indicates that the land use of Dujiangyan has been in a period of development with an increasing intensity,and the impact of human activities on the land use is increasing.At the end of this paper,we discuss the driving force of land use dynamic changes from the natural population,economic and other aspects.According to the main problems about land use of Dujiangyan,we put forward a basic model which makes overall coordination and whole control of land use,and provide an important suggestion for Dujiangyan’s land management which will come into the leaping development period.