玛纳斯河流域景观格局变化与地形控制分析

Analysis of Landscape Pattern Evolution Characteristic and Terrain Gradient Feature from 1990 to 2010 in the Manas River Basin,Xinjiang

以1990年、2000年、2005年、2010年四个时期的土地利用覆盖数据,玛河流域DEM为基础数据来源,在ArcGIS软件和Fragstats 3.4的支持下,采用景观单元类型转移矩阵、主要景观演化类型的地形梯度分析和空间数据叠加等方法分析了玛纳斯河流域的景观格局现状和演变特征,以及这种变化的影响因素。研究结果表明:玛纳斯河流域1990—2010年土地利用类型变化显著,荒漠、草地、水域以及林地面积都出现了不同程度的减少,耕地面积不断增加;玛纳斯河流域斑块形状总体趋向规则与简单的发展趋势;景观单元演变的地形梯度特征显著,表现为在各高程梯度、坡向梯度以及坡度梯度分布存在明显的地域分异规律,尤其与高程和坡度因子密切相关。说明玛纳斯河流域在经济快速发展的同时土地利用越来越丰富,规模和强度也在增大,但影响了景观稳定性和抗干扰性能。

Landscape pattern analysis is the intuitive way to recognize the evolution of the regional ecological environment. We took the Manas River Basin as study area, and obtained the changes of data relating to landscape pattern indices using ArcGIS and the landscape pattern analysis software Fragstats 3.4 with remote sensing images of 1990, 2000, 2005, 2010 and digital elevation model data as information source. Some methods such as landscape transition matrix, spatial data overlay analysis were used to analyze the main land- scape evolution and evolution of landscape pattern characteristics as well as the factors. The primary conclu- sions were as follows. Land use changed significantly, the landscape pattern concentrated mainly in the transformation of grassland and unused land to farmland and urban and rural, industrial and residential lands. Patch shape trended to simpleness and regularity in general. Topographic gradient feature of the land- scape unit transformed significantly, showing that each elevation gradient, slope gradient and slope gradient distribution existed obvious geographical diversity, particularly were closely related to the elevation and slope factors. It was described that land use has become increasingly diverse with the rapid economic development, the scale and intensity also increased, but it impacted the landscape stability and robustness.