塔里木盆地北缘绿洲景观格局变化与稳定性分析

利用渭干河—库车河三角洲绿洲1989年和2001年的遥感影像数据,借助RS和GIS技术,运用景观生态学原理,对该绿洲的景观格局变化进行动态分析,研究结果表明,在12年间,盐碱地、水体和灌丛斑块数目增加,农田和荒地斑块数目减少;占景观基质面积较大比例的农田和荒地相对较为稳定,而盐碱地变化最为显著,73.40%的盐碱地转化为其他类型,其中向灌丛和荒地转移的数量分别为27.20%和36.93%;景观多样性指数、均匀度指数和稳定性指数均呈现出下降趋势,优势度指数呈上升趋势,而破碎度指数的变化并不显著,绿洲生态系统向无序和不稳定方向发展。

Analysis on the landscape pattern and oasis stability in the northern margin of Tarim Basin

This paper will focus on the change of landscape pattern in the Delta oasis of Weigan and Kuqa Rivers which are located in the North of Taklamakan Desert.We will calculate and analyze some landscape indexes of the study area,such as diversity,evenness,dominance,fragmentation and stability of the landscape.It is found that the change of farmland and abandoned which have large percent in total area are stability relatively.Then,the 73.40% of saline-alkali transited to shrubs and abandoned.The decreased notably diversity index and evenness index that may explain the heterogeneity degree of landscape is descending.However,dominance index increased that shows fewer patches control the land-use landscape pattern of whole study area.The fragmentation index increased isn＇ t remarkable.In generally,these changes indicate that water,saline-alkali and lawn have increased extensively;farmland and abandoned（badlands） have decreased;the system of oasis ecology has become indirection and instability.