基于GIS的岷江上游流域土地利用／覆被变化研究

以岷江上游流域为对象,选取3期9景TM/+ETM遥感影像,通过多步骤最大似然监督分类、变化检测,结合空间动态分析测算模型,分析近20年土地利用/覆被变化情况。结果表明:从整个流域分析,林地面积减少,主要转化为未利用地、建设用地和耕地;未利用地在前8年以每年3.7%、后8年以每年0.4%的速度增加;建设用地在1994—2002年以每年34%的速度增加,到2002—2010年增长速度减缓;耕地总面积减少54 431hm2;从县域分析,1994—2002年间,松潘和黑水县大面积林地转为未利用地;2002—2010年间,松潘县未利用地转为林地和建设用地,茂县和汶川县未利用地面积大幅增加。该研究结论不仅为国土资源管理部门优化土地利用结构提供依据,亦为当地政府实现生态资源可持续发展提供数据支撑。

Research on land use/cover change on the upper of Minjiang River based on GIS

With the upper reaches of Minjiang River as the research object ,this paper adopts 3 periods and 9 scenes from TM/ETM + remote sensing image data .Through visual interpretation ,multi‐step maximum likelihood supervised classification ,change detection ,combined with the spatial dynamic analysis calculation model ,it analyzes the land use/cover changes of the basin in recent 20 years .The results show that :(1) considering the overall basin ,area of w oodland is declining ,mainly converted into unused land ,construction land and cultivated land .Unused land has increased respectively at the rate of 3.7% and 0.4% per year . Construction land has increased sharply at rate of 34% per year from 1994 to 2002 ,and the speed of grow th has slowed down from 2002 to 2010 .Arable land has decreased 54 431 hm2 ;(2)considering the county space ,area of woodland has been converted into unused land in Songpan and Heishui from 1994 to 2002 . From 2002 to 2010 ,the area of unused land hasbeen converted into w oodland and construction land in Songpan ,of which the land use/cover change in Lixian is relatively stable , and unused area greatly increases in Maoxian and Wenchuan ,mainly distributed in the drought river valley .The results can be used not only for land and resources management departments to optimize the land use structure ,but also for the local government to realize sustainable development of ecological resources .