北京市景观演变与生态环境变迁研究

Study on the Landscape and Eco-environment Evolution of Beijing City

基于北京市1975~2002年5期MSS和TM遥感资料及该区的地理资料,通过图像处理和GIS分析,探讨整个北京市域范围内景观组分的变迁规律以及生态环境的相应变化。研究表明：27年间北京市景观生态组分结构变化较大,自然景观组分略增,半自然景观组分大幅度下降,人文景观组分迅速增加,且主要由半自然景观转变而来,说明城市建设用地主要占用的是耕地,同时也表明人类干扰强烈;此外,在不同的时段,景观组分之间景观类型的转变也比较频繁,景观组分转换比例较大的是半自然景观组分,说明半自然景观组分是北京市的一种相对不稳定的景观类型。在生态环境方面,市域内自然景观组分的增加,主要是水体、城市绿地、植被覆盖度的增加,与1975年相比,北京市的生态环境质量正在逐步提高,城市内部的环境质量也得到了一定改善。

On the basis of MSS and TM remote sensing data of 5 study periods during 1975-2002 as well as geographic data of Beijing City,evolution laws of landscape components and corresponding changes of the ecological environment are discussed through image processing and GIS analysis.The results show that structure of landscape eco-component changes greatly during the 27 study years,natural landscape components slightly increase,semi-natural landscape components drastically decline,humanistic landscape components increase fast and are mainly transformed from semi-natural landscape components,that is to say,urban construction land occupies a great number of farmland,and human interventions are serious;moreover,transformation among landscape components is also frequent in all study periods,semi-natural landscape components witness the largest transformation ratio,so semi-natural landscape components are a kind of relatively instable landscape in Beijing.In terms of eco-environment,natural landscape components within the city increase which is specifically demonstrated as increase of water,urban green space and vegetation coverage;compared with the data in 1975,it is obvious that eco-environment quality of Beijing is gradually improving,and urban environment quality also promoted.