Study on spatio-temporal change of cultivated land in Xinxiang City using remote sensing and GIS

Abstract

A time series of Landsat Thematic Mapper (TM) satellite images are used to examine changes of cultivated land in Xinxiang City, Henan Province of China. After data processing and interpreting, information of cultivated land is extracted in the late 1980s, 1995, 2000 and 2005. Then, the paper mainly focuses on the spatio-temporal change study of cultivated land in Xinxiang City. Time series model, cultivated land changed degree model and fragmentation index are used to analyze the change of cultivated land and its subclasses in quantity. The results show that with time varying, cultivated land area as well as area of its subclasses, dynamic degree and fragmentation extent has been changing all the time and the size of change area is not the same at different periods. And both decreasing and increasing exit. Next, GIS spatial analysis and barycenter transfer model are used to analyze the spatial change of cultivated land. The outcomes of transfer matrixes reflect that the change course of cultivated land had two aspects including roll-in and roll-out, and although there are many interchanges between cultivated land and forest, grassland, water region and unused land, the urbanization and economic development are main reasons for the loss of cultivated land. Through calculating the barycenter, the results show that on the whole, the cultivated land barycenter in Xinxiang has a trend of moving southeast, reflecting that cultivated land in southeast part had a smaller reduction than northwest part.