The remote sensing mechanism and spectral characteristics of water bodies and other objects in SPOT 4 imagery were analyzed. Due to the similar infrared spectral response feature of water bodies to those of the objects under the mountain shadows in the imagery

thresholding for infrared bands is not suitable for the extraction of water bodies. The decision tree algorithm including several classifiers was put forward

which can extract water bodies effectively and easily. The terrain information and geometric features such as perimeter

area

and shape

which are frequently used in visual interpretation

can be used to classify water bodies into subclass. The decision tree algorithm including several classifiers associated with terrain and geometric information was developed to classify water bodies. Jiangning county of Jiangsu Province was selected as a case study area

SPOT 4 （XI

1999.1） and contour data of the area were used as information sources

the results after applying the proposed approach were satisfactong.