Land use change analysis and prediction in Wuhan,China based on remote sensing

摘要

Land use/cover change has brought about unprecedented negative impacts and consequences.Many Chinese cities like Wuhan is undergoing great changes in land use with accelerated urbanization and industrialization.Wuhan,in the middle reaches of Yangtze River,is the largest city in central China and has experienced rapid growth in recent years.This paper used remote sensing to analyze land use change process from 1987 to 2005 and to project land use change scenarios for the next 15 years in Wuhan.Three Landsat Thematic Mapper (TM) images taken in 1987,1994 and 2005 were employed to obtain land use change information.Maximum likelihood method was used,and the study area was classified into five major types of land use: agriculture,forest,water,urban or built-up,and barren land.The overall accuracy of each image was higher than 85%.Results showed that the predominant land use types were agriculture,water,and urban or built-up land.The marked change occurred in urban or built-up land,the size of which expanded 0.99% yearly during 1987-2005 period.Agricultural land reduced by 0.27% yearly during the same period and was mainly converted into urban or built-up land.Water area underwent a slightly increase during 1987 and 1994 but then decreased by 0.05% yearly from 1994 to 2005,most of which was converted into agricultural land.Forest reduced during the first period but then increased for the latter period.Future projected land use change scenarios were constructed by using a first-order Markov model.It was predicted that agriculture,forest,and water would decrease by 3185.14ha,213.64ha,and 174.23ha respectively,whereas urban or built-up land would expand 3853.27ha by 2020.Therefore,effective and timely measures should be taken to curb urban expansion to reduce further loss of agricultural land and water resources in the region.