Study the Role of Thermal Band for Land cover Mapping of Urban Area in Arid Lands; (Case Study; DAMGHAN City Lands, IRAN)

Over than three_ forth of lands in Iran are located in arid or semi arid environment. There are 60 playa in Iran which covers about 67250 square kilometers. Major part of human settlements in such a areas are subjected to the problems such as desertification, sand blowing, salinization, vegetation deterioration and erosion. Sustainable management of such lands especially for areas which are near the playa due to inaccessibility and limitations in resources is a challenging task which is need up-to-data and precise information for land covers situations. In this context, remotely sensed data, especially because of clear sky, shortage of rainfall and thus low moisture contents, has been showed very promising and valuable tools in arid lands. In most of studies, due to lower resolution (60 m) of thermal bands comparing to other SWIR and VIR bands (30 m), this band, despite of bearing valuable information are being eliminated from processing and classifications. In this research, the data of Landsat 7 (ETM+) Path/Row 163-35, dated 20 July 2000 acquired. Using Visual _ Digital Analysis (VDA) such as color composite, feature space and spectral signature analysis, homogeneous classes are defined. Then based on field works, auxiliary data and GPS points, 19 classes were defined. In order to study the role of thermal bands and contribution to accuracy improvement, four combination bands feed to maximum likelihood classifiers. The result showed, for such a studies in arid lands, thermal bands despite of lower resolution, is essential which including valuable information and could improve accuracy.