基于Landsat TM的西安地区土地利用变化与图谱研究

Landuse Change and Map in Xi'an Region Based on Landsat TM Images

利用两期TM影像,通过遥感与GIS技术,结合景观生态学理论和地学信息图谱理论,深入分析了10 a来西安地区土地利用变化的数量和空间特征以及由此所引起的一系列生态环境效应。研究区城镇建设用地面积显著增加,水体、耕地、林地面积呈减少趋势。城镇建设用地的增加是以侵占大量农田为代价的。景观破碎度变大,形状趋于复杂,优势度降低,多样性和均匀性增大,景观类型有向多样性或均衡化方向发展的趋势。景观的匀质化发展降低了景观抗干扰的能力,同时导致景观稳定性降低。分析表明,研究区内土地利用变化以各类型转化为城镇建设用地的趋势最强,在一定程度上显示了研究区正处于城市化的快速阶段。

Based on TM images （path 127, row 036） acquired in August, 1990 and May, 2000 respectively, five types of landuse were classified with the support of remote sensing and GIS. Using the theory of landscape ecology and geographic information images, we made quantitative analyses of the quantity and spatial feature changes of landuse in Xi＇an region in the period of 1990 to 2000, and a series of ecology environmental effects. Landuse change/cover in Xi＇an region can be listed as follows： Urban construction land increased sharply, while water-body, arable land, and forestland decreased apparently. Arable land and water-body were more fragmentary and interspersed than ever before. The increase in the area of urban construction land was at the cost of encroaching a wealth of arable land. Landscape became more and more fragmentized and the shape of landscape became more complex. The predominance index decreased as well. The Shannon diversity index increased from 0.90 to 1.02. while the Shannon evenness index increased from 0.48 to 0.56. It indicates that the landscape is getting more and more diversified and balanced, but poor to withstand the interference. It also indicates that human activities disturb the landscape more and more seriously. The results suggest that the trend that all the other land types translated into construction land appears much more dominantly than any others in the study region. In the meantime, the results also show that the Xi＇an City is in a fast developing stage of urbanization to a certain extent.