Simulation Of Land Use Change And Spatial Pattern At County Level In Black Soil Region

Land use and land cover change(LUCC)is one of the most important anthropogenic factors affecting terrestrial,so research on it has become the front in global change and hot present.Relayed on Natural Science Fund of Heilongjiang Province(D201410),this paper take the Wuchang of Heilongjiang province as the research area and three Landsat images of Wuchang at 2005,2010,2015 as the data sources.Based on ENVI Arc GIS,this paper gets the land use pattern,analyzes the Wuchang land use law.Transformed matrix of land use pattern is obtained with Markov model in IDRISI,Finally,under supports of CA-Markov model in IDRISI to simulate and analyze the land use pattern of Wuchang in 2020.The results showed:(1)Cropland and woodland are the main land use types in Wuchang,accounting for49.82%and 44.41%respectively.The area of Cropland and artificial surfaces increase steadily,woodland,grassland,water bodies and unused land decrease continually.The area of cropland has increased mostly by 345.01km~2,while woodland has decreased mostly by396.69 km~2,and the loss of woodland made a great contribute to the gain of cropland.The area of artificial surfaces showed a trend of increasing slowly.Grassland and unused land area were small,and the land use change of these two types of land were the most frequent.(2)Markov modle in IDRISI was used to obtain the land use type transform matrix in2005~2010 and 2010~2015.Results indicated that the cropland had a high retention rate of93.98%and 90.18%and woodland also had a high retention rate of 86.51%and 90.45%,respectively.Woodland and grassland were the main sources of cropland.Grassland had the lowest retention rate and it was mainly convert into woodland.With the Xilin River,Ashe River and many reservoirs in its territory,water bodies has a retention rate of 74.12%.(3)Under supports of CA-Markov model in IDRISI to simulate and analyze the land use pattern of Wuchang in 2020.Results showed:the area of cropland,woodland,grassland,water bodies,artificial surfaces and unused land are 3740.46km~2,3316.89km~2,54.43km~2,105.20km~2,255.32 km~2,28.24 km~2,respectively,accounting for 49.87%,44.22%,0.73%,1.40%,3.40%,0.38%,respectively.Cropland,water bodies,artificial surfaces and unused land area increased,woodland and grassland area decreased,compared with the previous two periods,the rate decreased,the speed slowed down.(4)In 2005~2015,the rapid development of the secondary and the tertiary industries had made them become the leading forces of economic development.There is a certain irrational land use phenomenon that cropland expand to the woodland and wetland.It is urgent to strengthen the protection of woodland and wetland to protect the woodland from decreasing and promote the rational use of land.By using ecological function as the dominant factor,four functional units of agroecosystem,water ecosystem,wetland ecosystem and urban ecosystem should be established and at the same time strengthen monitoring of the rational use of land to achieve the sustainable use of land resources.