ASTER和TM/ETM+遥感数据融合监测土地覆盖变化

在人们纷纷选择IKONOS、QUICKBIRD、SPOT-5等高分辨率影像监测土地利用/覆盖变化之际,以北京海淀区为例,尝试采用Brovey变换和主成分分析(PCA)法融合ASTER、TM/ETM+中等分辨率影像,充分利用ASTER、TM/ETM+数据的多光谱和较高空间分辨率特性,挖掘其在土地覆盖变化监测中的潜力,为大规模监测土地利用/覆盖变化提供科学参考。研究将2003年ASTER多光谱3N、2、1波段与1999年ETM+PAN波段进行Brovey变换;1992年TM543与1999年ETM+PAN波段进行PCA融合,快速发现土地覆盖变化信息。经验证,变化发现精度达92.50%,符合项目精度要求。试验表明:在缺乏高分辨率影像的地区,选择价格相对便宜的AS-TER和TM/ETM+数据,采用Brovey变换和主成分分析(PCA)法进行融合,可有效监测土地覆盖变化,节约动态监测成本,二者具有很大的应用价值,值得推广。

Merging ASTER with TM/ETM+ data to monitor land cover change

Monitoring land-use and land-cover change usually uses high spatial resolution images,such as IKONOS,QUICKBIRD or SPOT-5.In this paper,taking Haidian district for example,the authors merge ASTER with TM/ETM median resolution images by Brovey transform and principal component analysis(PCA)methods,attempting to make full use of multi-spectral and higher spatial resolution characteristic of ASTER and TM/ETM images,even to mine their potential which can be used in land-use and land-cover change.This paper may provide scientific reference for cosmically monitoring land-use and land-cover change.The authors have merged multi-spectral(bands 3N,2,1)ASTER image of 2003 with panchromatic ETM image of 1999 using Brovey transform Method,and fused TM543 color composition images of 1992 with ETM PAN of 1999 by PCA method,finally,as a result,both fusion images can show change clearly.By tested,the precision of change information detection arrived 92.50%,which accords with the demand of application.In this study,the result shows that cheaper ASTER and TM/ETM data fusion may efficiently monitor land-cover change,especially in the region without high resolution data,which can save the cost of dynamic monitoring.Meanwhile,it indicates that ASTER and TM/ETM images have large utility value,and deserve extensive use.