钦州市城市扩张的生态响应

Urban Expansion in Qinzhou City and Its Ecological Response

关键词:  生态变化  城市扩张  主成分分析  遥感生态指数  生态环境评价  钦州市

Key words:  ecological environment changes  urban expansion  principal component analysis  Remote Sensing Ecological Index (RSEI)  ecological evaluation  Qinzhou City

摘要:

为量化分析评价钦州市城市扩张对生态环境的影响，选取2000年、2009年和2017年的Landsat系列影像数据，提取绿度、湿度、热度、干度4个评价指标，用基于ENVI平台的主成分分析方法构建遥感生态指数（RSEI），评价该地区的生态环境状况。结果表明，2000年、2009年、2017年钦州市的RSEI均值分别为0.676，0.698和0.725，生态状况有改善的趋势，说明城市的扩张给钦州市整体生态带来的负面影响不大，钦州市仍有很大的发展潜力。对该地区而言，植被覆盖对生态环境起决定作用。低生态等级区的平均中心随城市扩张的方向迁移，表明城市的扩张对生态有一定的负面影响。部分建筑用地的生态等级由差变好，表明绿化工程能改善区域的生态质量。

Abstract:

In order to quantitatively analyze and evaluate the impact of Qinzhou's urban expansion on the ecological environment,the image data of Landsat series in 2000,2009 and 2017 were selected.Four evaluation indicators,which were normalized vegetation index (Greenness),humidity component (Wetness),land surface temperature (Heat) and normalized difference building-soil index (Dryness),were extracted.And the principal component analysis method was used to construct Remote Sensing Ecological Index (RSEI) to evaluate the ecological environment of the area.The results showed that in 2000,2009,and 2017,the mean values of RSEI in Qinzhou City were 0.676,0.698 and 0.725,respectively.The ecological situation trended to improve,which indicated that the expansion of city had little negative impact on the overall ecology of Qinzhou City.The city still had great potential for development.For this area,vegetation coverage played a decisive role in the ecological environment.The average center of the low ecological grade area moved with the direction of the urban expansion,which indicated that the urban expansion had a certain negative effect on the ecology.The ecological grade of some building land changed from bad to good,which indicated that greening projects could improve regional ecological quality.