榆林沙区景观格局特征与动态分析

Analysis on the Characteristics of Landscape Structure and Dynamics Changes in Yulin Sand Land

在对榆林沙区土地利用结构调查和遥感影像解译资料分析基础上,研究了榆林沙区景观构成和特征,分析了景观格局动态,结果表明:1)景观类型中林草地面积最大,占65.4%,在整体景观中优势突出(0.688),为主要景观类型;农耕地、居民建设用地占24.91%,表明人类活动在区域景观格局发展过程中参与的力度己十分强烈,成为自然景观格局变化最大的外来影响因素。2)榆林沙区景观破碎度很低(0.157),景观类型较单调,分配不均匀,景观多样性较低(1.501),稳定性差。3)近20a间,林地、草地、园地面积在整个景观格局中的比例增加了10.24%,而流沙地、盐碱地等难利用地景观比例下降了14.43%,反映了近年来榆林沙地治理力度和显著成效。但是,当地的城镇、工矿、交通、电力等各类建设用地面积增长了13.56%,在整个景观中的比例增加了0.57%,对区域人工植被乃至全区生态环境的影响也是不容忽视的。

Based on the investigation of land utilization structure and remote sensing image interpretation, the landscape constitution and characteristics of Yulin sandy land were studied, landscape pattern tendency was analyzed. The results indicated： 1） forests and grasslands were the main landscape types, accounting for 65.4%, and landscape dominance was 0. 688. The agriculture and resident construction land accounted for 24.91%; it indicateding that the intensity of human activities was very intense in the region of landscape pattern developing process, while becoming the main external factors of the natural landscape pattern changes. 2） In Yulin desert region, the landscape fragmentation degree was very low （0. 157）, the land scape type was monotonous and uniform, the landscape diversity was low （1. 501）, landscape pattern was unstable. 3） In the past 20 years, the areas of woodland, grassland and garden was increased by 10.24% in the entire landscape pattern＇s proportion, while the area of wind drift sand, saline and unused land dropped by 14.43%, reflecteding governance efforts and significant achievements in the recent years in Yu lin sand land. However, the construction land area, such as resident land, industrial, mining, traffic and urban etc. , increased by 13. 56%, while increased by 0. 57% in the entire landscape＇s proportion, whichwas indispensable in the regional artificial vegetation and the entire district ecological environment.