额济纳三角洲近15年土地利用分形特征及变化

分形理论在土地利用变化领域有着广阔的应用前景。通过论述土地利用斑块分维数、稳定性指数的计算方法及代表意义。而后,借助遥感和地理信息系统空间技术,以额济纳三角洲为例,计算了沙漠化地区土地利用斑块的分维数和稳定性指数,分析了它们的变化特征及其所隐含的地理学意义,为区域生态环境保护和可持续利用提供决策依据。

Fractal character and change of land use in Ejina Delta during the past 15 years

Fractal theory is a new tool for LUCC study and it has a broad prospect for application in this field.In this article,the calculation method and representative signification of patch fractal dimension and stability index have been expatiated.With the support of RS and GIS spatial technology,taking Ejina delta as example,the patch fractal dimension and stability index of land use are calculated in desertification region.The variation character and its potential geographical meaning have also been analyzed.The results show that(1) great changes of land use have taken place in Ejina Delta from 1987 to 2001,especially evident change of water domain makes Ejina Delta region facing serious ecology pressure;(2)ecotone between oasis and desert is usually the most sensitive and unstable region,so more protection and management should be actualized at ecotone between oasis and desert in the process of desertification prevention and land use planning;(3) because of decrease of water replenishment and increase of exploitation and utilization underwater,more and more desertification shrubs translates into desertification pasture and the eco-environment in Ejina Delta region would be deteriorated further;(4)with the sharpening of desertification,small area oasis will be lost in Gobi and sandlot and the area of difficult use land increases more and more,which means the restoration would be very difficult.Some piece of advice of regional environmental protection and sustainable utilization was given in the end.