Assessment Of Land Use Planning Impact On Ecological Environment At County Level Based On The Grid Cell

The land use planning is a macro-strategic measure which coordinates the total supply and the aggregate demand of land, determines and adjusts structure and layout of land use according to natural and socio-economic conditions and requirements of national economic development. The implementation of land use planning would have impact on the environment of the planning region. While the positive effect may optimize the regional environment, the negative one may cause serious environmental issues that seriously affected harmonious socio-economic development. Therefore, the assessment of land use planning impact on ecological environment plays a vital role both in protecting the environment and reducing the negative environmental impact of land use planning. Researching evaluation methods and establishing appropriate evaluation systems which are suitable for the assessment of land use planning impact on ecological environment is one of the key points for the study.Using PSR model and the ecological security assessment, the assessment indexes were picked out based on grid cell. After screening indexes through correlation analysis, an evaluation system of the land use planning on ecological environment impacts was constructed. Combined with spatial analysis through GIS, the environmental impact of land use planning at county level was quantitative evaluated.The proposed the methods are applied in Yongding county, Hunan province. After the analysis of the environment status and the main ecological security problems in Yongding County, which threatened the survival and development of economy and human society, the environment evaluation system of the land resource planning in this area was established. The environmental impacts of land use planning are assessed through comparing the environment status index and ecological security index, which are different before and after the land use planning taking effect. Results indicate that most of the area (about 78.19%) would be benefit from the performing of the new general land use planning. At the same time,60.17% of this area would be in the statues of secure and relative secure, which means a slight improvement in soil and water loss. Enhancing soil and water conservation would still be one of the priorities of the ecological environment protection in Yongding County.The results of analyzing the effects of spatial scale are indicated as: with the grid size decreases, the EI of most of the regional (more than 89% of the area) is still in normal state, which showed the trend of gradual reduction; the areas of two levels (excellent and poor) gradually increased. However, the evaluation results for the region as a whole is stable. Therefore, the grid size selecting should meet the actual evaluation needs.