Study on Land Cover/Use Change in Changping District of Beijing Based on RS Technology

Land use is a particular area, where there is the special product to affect feature of natural, economic, technological and social condition. Remote sensing plays a significant role in analysis on land use change. In this paper, it attempted to identify the dynamics of the land cover/use changes by using M images at three periods of 1992, 2001 and 2005 in Changping district of north Beijing in China base on transition matrices trough ERDAS RS process software. Firstly, because of different classification level of land cover/use at three periods, the unified classification system should be built up by referenced on the local governmental policies of land use, The land use types were divided in seven categories: riparian zones(Rip), cultivated land(Cul), forest(For), orchard(Orc), grass land(Gra), built-up land(Bul) and unused land(Unl). Then it applied supervised classification and unsupervised classification to obtain the land cover/use map of three periods. Finally, it calculated the process of land cover/use changes by using transition matrices. The results indicated that over the past 20 years, land use in Changping underwent considerable changes, the total change areas during the periods 1992-2001 and 2001-2005 respectively were 937 km2 and 777 km2, which respectively occupied to 69.7% and 57.7% of the total area. Mainly change of land cover/use was cultivated land swift into forest, orchard and build-up land. The result of land cover/use change could have larger relationship with policies of government.