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.