Simulation Research On Land Use/Cover Change In Nanliu River Basin

In the past,the world's industries and towns grew slowly.Humans have experienced massive development of the earth's surface to meet their own production and basic needs.During this time,forest boundaries have shrunk and been damaged to varying degrees.Land is an important part of global ecology,and forest is an important component of land surface.At present,one of the main ways of human disturbance is land use/cover change and the other is deforestation.The most obvious impact of human activities on natural environment and ecosystem is land use/cover change.With the development of the society and the improvement of economy,the interference of human activities occurs frequently.How to use the land scientifically and balance the internationally recognized sustainable development strategy of land is a test that all mankind needs to face at present.In this paper,land use data with a resolution of 30m*30m were obtained from remote sensing images covering 30 years(1990,2000,2005,2010,2015 and 2020a)in the Nanliu River Basin.The process of land use/cover change in historical periods of the basin was analyzed,and the future land use change in the basin was simulated by combining Markov chain and PLUS model.The main research conclusions are as follows:(1)Based on the overlay analysis of land use data,the spatial distribution characteristics,and transfer quantity of land cover change in the Nanliu River Basin in different time periods were obtained.The results show that woodland is the most widely distributed land use type,followed by cultivated land,garden land,towns,villages,industrial and mining land,water and water conservancy facilities land,grassland,and other land.In the past 30 years,with the development of social economy and the improvement of industrial level,the area of land for construction and mineral exploitation has been increasing,while the area of arable land and grassland has been declining.After 2005,the social economy and industry in the basin developed rapidly,while the passive attitude of land use/cover changed obviously,and the area of land use transfer in and out increased,especially in Qinnan District,Beiliu City,Yuzhou District and Luchuan County.It shows that Nanliu River basin has unique natural conditions,but there are some problems of tension between people and land in the process of social development.(2)The forest land area in Niliu River Basin changed significantly from 1990 to2020.By 2020,forestland is the main body of forest resources in the basin,which covers 88.99% of the total forest area.Among forestland,eucalyptus forest and masson pine forest are the dominant species,occupying 60.56% and 12.37% of the forestland area,respectively.For many years,the forest mainly flows to the cultivated land,the garden,the town village,and the industrial and mining land mainly.By analyzing the spatial distribution of different tree species at different elevations,slopes,and slopes,it can be concluded that the topographic distribution of woodland is the result of the interaction between human activities and environment.(3)by getting the driving factors of south stream river watershed land use change is analyzed,by using the module based on the analysis of land expansion strategy PLUS the transformation rules mining,by setting the corresponding parameter,and transformation rules,seed mechanism module in the kinds of random plaque computing research in various land use type growth mode of each patch.Finally,CA model was used to simulate the distribution of land use in 2020.In order to achieve the accuracy standard,the parameters were adjusted continuously and the restricted conversion area was set.Finally,the Kappa coefficient and FOM index of the simulated 2020 land use distribution document reached 0.801 and 0.126.The pixels of several plots were randomly selected and compared with the real data,which showed that the simulated results were very close to the real images with high reliability.(4)Based on the Markov chain to predict the amount of land use/cover in the watershed in the future,simulate the land use change under different scenarios in 2030 based on the above-trained PLUS model,and compare the evolution of land use/cover change in different periods trend.The results show that the PLUS model has a certain degree of rationality and scientificity when simulating changes in the watershed.The simulated FOM coefficient under the ecological protection conditions in 2030 reaches0.298.In the future,the development prospects of towns,villages and industrial and mining land will continue to spread to the surrounding areas mainly in the old city,and the planting range of artificial eucalyptus forests will continue to develop in areas with high altitudes and steep slopes.