Rural Land Ecological Suitability Assessment And Its Application Based On GIS

China is in the accelerated development period of building new socialist rural communities, which causes mounting pressure to the ecological environment in rural area. To coordinate the relationship between countryside construction and ecological environment protection has become an urgent and arduous task currently.As an effective means of finding out land ecological suitability level and distribution of a planning area, land ecological suitability assessment has vital role in developing the land from its internal ecological suitability and ensuring the rationality and sustainability of land use. Thus, assessing the land ecological suitability with more scientific, reasonable and accurate methods to provide scientific basis and technical support for land use planning in rural area has important research value and practical significance.On the basis of learning the research achievements of land ecological suitability assessment both domestic and abroad, with high resolution aviation remote sensing image as data sources and by the support of GIS technology, this thesis studied land ecological suitability assessment in village domain range, which includes selecting the assessing indicator system, determining the weights of indicators, dividing the assessing units, building the assessing model. And the data processing of evaluation factors and establishing of database based on GIS data processing and database established. Then, taking Yannan village as an example, the thesis verified the land ecological suitability assessment model, and explored the application of land ecological suitability assessment in the village land use planning. The main achievements of the thesis are as follows:(1) Explicit the combination weighting as the method to determine the weights of evaluation factors, superposition method and grid-based method as the way to divide evaluation units, and use factor weight sum method to establish the accessing model.(2) Build a land ecological suitability assessment model of Yannan based on index weight sum method. As follows:Ei=0.0694×[elevation]+0.0464×[slope]+0.0326×[aspect]+0.2669×[vegetation coverage]+0.1638×[biological richness]+ 0.0362×[soil texture]+0.0445×[soil thickness]+0.1278×[water resources]+0.0995×[transit influence]+0.1132×[rural residential area influence]. Evaluation results show that the average level of land ecological suitability of Yannan is good with Ei=62.568. The highly plantation area of land ecological suitability of44.4hm2, accounting for33.89%of the village, while the moderate plantation of28.8hm2,28.8%. The area of common plantation is29.3hm2for22.34%and the basic plantation area is28.5hm2for21.78%.(3) The result of land ecological suitability assessment can provide scientific basis for village land use planning in some ways as land use status analysis, function zoning, space layout and control measure making. According to the result of land ecological suitability assessment in Yannan, the thesis divided Yannan into5areas, as ecological protection area, basic farmland protection area, general farmland area, the construction area and travel area.(4) By using remote sensing information extraction technology and GIS spatial analysis function, analyzed the assessing indicators and constructed database of land ecological suitability assessment indicators in Yannan based on ArcGIS9.3, which concluded spatial graphic database and spatial attribute database.