Abstract:
Agricultural crop area extraction using remote sensing technology has been proved to be a practical and feasible method, thus numerous researches and studies have been done by many scientific institutions worldwide. This paper, a new method for extracting winter wheat area of Gaocheng County, Hebei Province, using multi-temporal Terra/MODIS images is presented. At first, based on the analysis of spectral features of MODIS data and biological characteristics of winter wheat, four bands(Red, Blue, NIR, ESWIR bands) of MODIS data were selected as the basic processing bands, and the impact of VI images on accuracy of acreage detection was also taken into considerations during this stage. Then four different methods were applied to the MODIS images for sown area extraction at a town level in 2004. The accuracy assessment results by using 2004 statistical data and land use map product indicated that the acreage derived from MODIS data using four methods coincided well with the real conditions, with both a total and average error less than 5%. Therefore, it is concluded that the coarse resolution MODIS image can be utilized in agricultural crop sown area extraction, the most appropriate MODIS temporal data for such applications are the combination of Red, Blue, NIR, ESWIR bands at tasseling stage and EVI image at emerging stages of winter wheat.