Research And Application Of Suitability Evaluation Method For Construction Of Low Hills And Low Slope Based On Model Builder

Yunnan province is located in the southwest of China, and belongs to plateau mountainous area, its mountain area is really vast and land resources are very limited, where mountains contain plains, plains contains valleys, showing various dispersion in spatial-combinations. In recent years, with the further development of social economic in Yunnan province, in order to meet the increasing needs of urban and rural construction land, and then a large number of non-urban-construction-land will be converted to urban-rural construction lands. As a result, the cultivate land resources nervous situation and the contradiction between the supply and demand of land more and more serious. Under this circumstance in China, cultivated land resource is very in short supply, especially, is strictly protected, so the development and utilization of land resources in the low hilly land resource will be the best choice of urban construction to exploit. However, the high degree of sensitivity of the complexity of ecological environment of low hilly land resource determine that it is a limited choice to exploit and use mild slope of low mountains and hills resource.Based on the facts mentioned above, in this paper taking into account the characteristics of the natural environment and social economic conditions of Dali City, Yunnan Province, gives a clear definition of land resources in low hilly in the City. Using the date of Dali 2011 land change survey data and based on the data for improvement of the overall planning of land use data (2010-2020), combined with the definition of mild slope of low mountains and hills, the low hilly land resources has been extracted by using GIS spatial analysis approach. Then, the construction of appropriate division of evaluation unit have been completed using ArcGIS9.3 platform, the determination method of evaluation factors and weight factor method have been discussed, the appropriate method to determine the weight of evaluation factors has been conducted. With reference to the principle for choosing evaluation indicator factor for land suitability and with definition of land suitability, after the study of single factor and multi factor index system, the low hilly land resources of Dali city construction land suitability evaluation system has been established. The evaluation system has a hierarchical structure that includes target layer, control layer and index layer, and chooses the natural factors (geology tectonic, slope, elevation, traffic conditions, etc.), social and human factors (land use status) as a general evaluation factor. At the same time, according to the complex and higher degree of sensitivity of characteristic of the ecological environment in low hilly land resources, a special one-vote veto evaluation factors have been introduced to establish the low hilly land resources of Dali city construction land suitability evaluation system.According to the established evaluation system, a model based on the multi factor comprehensive evaluation model for improvement of low hilly land resource construction suitability evaluation model has been suggested, and using the analytic hierarchy process and graphic overlay method, the construction land suitability has been evaluated for each general factor of land resource mild slope of low mountains and hills in the city., and then through the ArcGIS Model Builder model editor, the city construction general evaluation of low hilly land resource suitability evaluation model has been created to obtain the factor of the city low hilly general factor construction suitability evaluation. Eventually, adding to the special modified factor, the final low hilly land resource suitability evaluation of construction results have been obtained. The low hilly construction land resources of the city will be divided into four levels, which is the first-class suitability, the second-class suitability, the third-class suitability and unsuitability. From the city, the hilly slope construction suitability evaluation results show that low hilly land resources of the city is very large and suitable for urban development of the hilly slope construction, and the potential is relatively large, but the process of utilization will be restricted by some factors. Finally, based on the mild slope of low mountains and hills construction suitability evaluation results, the comprehensive utilization of land resources in the City, mild slope of low mountains and hills are analyzed, and according to the different areas, the actual, put forward the direction for the use of land resources in each area of the mild slope of low mountains and hills.Conclusions from results of the study could be summarized as follows:(1)The factors that influence the construction land suitability evaluation of mild slope of low mountains and hills are more complex and comprehensive. (2) the index system of special factor index and basic factor index combining structure match more than single factor index system and the low hilly land for construction land; (3) for the low hilly land suitable evaluation GIS technology is a comprehensive and effective means; (4) The improved multi factor comprehensive evaluation model are more suitable for low hilly land resource suitability evaluation of construction in areas of wide mountain, and varying terrain;(5) Due to the Model Builder’s automatically data processing characteristics, using ArcGIS Model Builder model editor to create low slope hilly land suitability evaluation of construction model, can make the evaluation more quickly and accurately; (6) the data collection situation will depend on the evaluation factors selection and will influence the choice of evaluation methods; (7) the evaluation regions of the city in accordance with the construction suitability level can be classified into four grades which are the first-class suitability, the second-class suitability, the third-class suitability and unsuitability in Dali.