基于GIS的隆昌县耕地适宜性评价

发布时间：2019-03-31 10:57

【摘要】：耕地是我国最重要的土地资源，保持稳定的耕地资源总量是国民经济持续发展和社会安定的基础。土地适宜性评价就是评定土地对于某种用途是否适宜以及适宜的程度，它是进行土地利用决策，确定土地利用方向的基本依据。耕地适宜性是土地适宜性评价的主要内容之一，通过对用于耕作的土地进行适宜性等级的划分，揭示其作为耕地的适宜性程度的高低，从而为调整和优化土地利用结构，，制定合理的土地开发整理规划提供科学依据。本文基于四川省内江市隆昌县永久基本农田划定工作建设项目，把土壤资源普查数据作为耕地土壤性状信息的来源数据，地理信息系统作为空间数据管理与分析的手段，层次分析法结合特尔斐法作为选取评价因子和确定其权重的方法。通过优选出能代表隆昌县耕地质地的评价因子，初步建立隆昌县耕地适宜性评价控制指标体系及权重等级划分。本文选取地形坡度、海拔高度、土层厚度、耕层质地、土壤PH值含量、土壤氮含量、土壤磷含量、土壤钾含量、土壤有机质含量、排水条件、剖面构型、水利条件、交通条件等13个评价因子建立本次耕地适宜性评价的评价指标体系，并运用层次分析法和特尔斐法确定其权重。评价中的地形指标数据直接从隆昌县的30mDEM中提取，对DEM进行地形分析可以得到隆昌县的高程信息图和坡度信息图。利用GIS技术，提取出各评价因子专题图层，对各图层进行叠加。采用层次分析法及特尔菲法确定各评价因素权重，采用指数和法计算各评价单元的综合分值，并进行分等定级，最终得到隆昌县耕地适宜性评价结果。隆昌县的耕地适宜性评价的结果显示：高适宜区的总面积9746.64ha，占耕地总面积的18.26%，主要分布在隆昌县的东南部地区；中适宜区的总面积为16259.35ha，占耕地总面积的30.47%，中适宜性区分布范围较广，主要分布在隆昌县的东部、西南部以及中部地区；边际适宜区的总面积为15814.39ha，占耕地总面积的29.63%，主要分布在隆昌县的东南部、中北部以及中部地区；不适宜区的总面积为11552.26ha，占耕地总面积的21.64%，主要分布在隆昌县的北部以及西北部地区。隆昌县耕地适宜程度的评价，为以后的土地总体规划和土地类型的调整提供了一定的依据，并针对不适宜区的主要限制因素，提出了改善目前状况的建议。本次研究在GIS/RS的基础上进行了空间专题数据的提取和分析处理，结合了层次分析法和特尔斐法确定耕地适宜性评价指标系统并确定了每个评价因子的权重，最终得出了分析结果。整个处理过程基本实现了数据处理的自动化，大大的减少了人的工作量，提高了数据处理的精度和效率。对以后这方面的研究具有一定的参考价值。
[Abstract]:Cultivated land is the most important land resource in our country. Maintaining stable total cultivated land resource is the foundation of sustainable development of national economy and social stability. The evaluation of land suitability is to assess whether or not land is suitable for a certain use and the degree of suitability. It is the basic basis for land use decision-making and determination of land use direction. The suitability of cultivated land is one of the main contents of the evaluation of land suitability. By dividing the suitability grades of land used for cultivation, the degree of suitability of cultivated land is revealed, so as to adjust and optimize the land use structure. Make reasonable land development and consolidation plan to provide scientific basis. Based on the construction project of permanent basic farmland delineation in Longchang County, Neijiang City, Sichuan Province, this paper takes soil resource census data as the source data of cultivated land soil properties information, and geographic information system as a means of spatial data management and analysis. Analytic hierarchy process (AHP) combined with Delphi method as a method to select evaluation factors and determine their weights. By optimizing the evaluation factors which can represent the texture of cultivated land in Longchang County, the evaluation and control index system and weight classification of cultivated land suitability in Longchang County were established. In this paper, the topographical gradient, altitude, soil thickness, soil texture, soil PH content, soil nitrogen content, soil phosphorus content, soil potassium content, soil organic matter content, drainage conditions, profile configuration and water conservancy conditions were selected. 13 evaluation factors, such as traffic conditions, were used to establish the evaluation index system of the suitability of cultivated land, and their weights were determined by AHP and Delphi method. The topographic index data in the evaluation are directly extracted from the 30mDEM of Longchang County, and the elevation map and slope information map of Longchang County can be obtained by terrain analysis of DEM. GIS technology is used to extract the thematic layers of each evaluation factor and superimpose each layer. The weight of each evaluation factor was determined by analytic hierarchy process (AHP) and Delphi method. The comprehensive score of each evaluation unit was calculated by exponential sum method, and the evaluation results of cultivated land suitability in Longchang County were obtained by grading and grading. The results of cultivated land suitability evaluation in Longchang County show that the total area of high suitability area is 9746.64ha, accounting for 18.26% of the total cultivated land area, mainly distributed in the southeast of Longchang County; The total area of the middle suitable area is 16259.35ha, accounting for 30.47% of the total cultivated land area. The middle suitable area is widely distributed, mainly in the eastern, southwest and central regions of Longchang County. The total area of marginal suitability area is 15814.39ha, accounting for 29.63% of the total cultivated land area, mainly distributed in the southeast, north-central and central regions of Longchang County; The total area of unsuitable area is 11552.26ha, accounting for 21.64% of the total cultivated land area, mainly distributed in the north and northwest of Longchang County. The evaluation of the suitability of cultivated land in Longchang County provides a certain basis for the general planning of land and the adjustment of land type in the future, and puts forward some suggestions to improve the present situation in view of the main limiting factors of the unsuitable area. On the basis of GIS/RS, this research carries on the extraction and analysis of the spatial thematic data, combines the analytic hierarchy process (AHP) and the Delphi method to determine the evaluation index system of the suitability of cultivated land and determines the weight of each evaluation factor. Finally, the analysis results are obtained. The whole processing process basically realizes the automation of data processing, greatly reduces the workload of human beings, and improves the precision and efficiency of data processing. It has certain reference value for the future research in this field.
【学位授予单位】：成都理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：F323.211;P208

【参考文献】