Study Of Land Use Optimization Based On Ecological Carrying Capacity

With the improvement of citizens’life qualities, the infinite nature of people’s needs and the limitations of land are becoming more and more contradictory. And it makes the conflict between the economic and social development and the ecological carrying capacity. How to achieve the sustainable development of economics and society with an acceptable ecological carrying capacity becomes a realistic problem that all the countries and all the regions, in any arid zone, have to face.The present study chose the Huailai County of Hebei province, which located to the northwest of Beijing and the upstream of Yongding River, as research object to study the land use optimization based on the ecological carrying capacity. The study is representative in the country, for the various geomorphic types of mountain, basin, touradon, river and reservoir, the complex vegetation form of woodland, farmland, garden, grassland and wasteland, and the advanced industrialization and urbanization process in Zhangjiakou region of Huailai County.The present paper studied the land use changes, ecological carring capacity, land suitability and land use optimization of Huailai County based on the methods of geographic information technoogy, ecological footprint, multi-objective programming and so on. Firstly, the characters, rules and reasons of land utilization changes were studied. By interpreting satellite images of Huailai County in2000,2005and2010to acquire the data of land use in Huailai, combining the investigation informations, using the transfer matrix and statistic methods, the explainations of land area composition, spatial distribution, dynamic change, the magnitude and velocity of change were studied. It was showed that during2000-2010, the land uses of each land type keeping on changing. The rate of change in descending order was as the unused land> urban and rural construction land> garden> waters> grassland> farmland> woodland. The dynamic degree of land use was1.26%in11years,1.91%in2000-2005and0.87%in2005-2010, respectively. Secondly, the paper calculated and analyzed the ecological carrying capacity based on the improved ecological footprint model. The limit factor and weighted index in classical ecological footprint model were improved with the ecosystem service value theory, to make the calculation result more truthful. Therefor, the ecological footprint, ecological carrying capacity, ecological surplus/deficit and ecological pressure of Huailai during2000～2010were studied. And the key effecting factors and the tendency of the changes were analyzed in depth. It is showed that during the11years from2000to2010, the ecological footprint per capita and the ecological carrying capacity per capita both increased, but they had different growth which made the ecological deficit per capita increase. Basically, the ecology of Huailai County was at a loss and unsafe in the11years, the ecological pressure index of2000is0.52, the ecological pressure index of2010is1.15, the average ecological pressure index was0.95.Thirdly, the land use suitability evaluation was carried out with index additive method and limiting factor method. According to the nature condition of Huailai, the selection of evaluation factors and the experts advisory result, the slope direction, elevation, slope, water resources, soil organic matter were chosen as dominant factors. With index additive method and limiting factor method and the GIS technology the suitability of land resources in Huailai were evaluated. The result showed that eastern and western plains were suitable for farmland and garden planting; northern and southern hilly area were more appropriate for garden, woodland and grassland; while the northern and southern mountains is more suitable for planting shrub and forests.At last, the land optimization prediction, analysis, evaluation and countermeasures were studied. The Markov forecasting model was used to predict the land use structures of Huailai County in2020. Using grey multi-objective linear programming model, taking ecological carrying capacity and economical benefits of land use as objective function, setting five scenes of optimal ecology, ecological priority, equal ecology and economy, economic priority and optimal economy to predict the land use structure. According to the ecological carrying capacities, economic benefits of different land use structures, the development needs of ecology, economy and society and the optional program, the equal ecology and economy was chosen as the best strategy:Compared with2010, the ecological carrying capacity increased39.50%, an economic benefit increased130.95%, which can basically meet the demand of economic development and ecological protection of2020for land need. Meanwhile, based on the results of land suitability assessment of Huailai County, and using analytical techniques of GIS for optimizing the spatial distribution of land use types in2020, Huailai County2020land use optimization map was obtained. Based on this optimization land use map, the corresponding development strategies were made, for water resources, farmland, woodland, orchard, grassland and construction land in Huailai County respectively, which provided advices and references for sustainable local development.