近30年关中平原耕地景观格局变化研究

Research on the Cropland Landscape Pattern Changes in Guanzhong Plain during the Past 30 Years

摘要: 耕地景观格局的变化对农业规划和耕地的合理利用具有重要的意义。本文以关中平原1980年代到2015年的六期耕地的矢量数据为基础，首先对不同市级行政区域耕地的动态度和耕地区位指数进行分析，然后以不同尺度的网格为分析单元，分析关中平原耕地景观格局随时间的变化趋势和尺度效应。研究结果表明：1) 在六期的耕地动态度变化中，除了西安市1980年至1990年和宝鸡市2005年至2010年的耕地是正向变化，其他时期都是负向变化。2) 在研究期间，渭南市的耕地集约程度最高，耕地开发力度不断增强；西安市的集约程度最低，耕地减少速度不断加快，地区经济的发展与耕地保护的矛盾加深。3) 研究区耕地总面积以“蚕食”的方式减少，同时耕地面积指数的布局呈现“环围式”的特征，减少区域以西安市为中心呈“放射型”分布。4) 在1 × 1 KM网格尺度下，耕地的破碎化现象加重与减弱的区域表现为混合分布的特征，但随着网格尺度的增加，耕地破碎化现象加重和减弱区域各自聚集。

Abstract: The change of cropland landscape patterns is of great significance to agricultural planning and regional cropland utilization. Based on six vector datasets of cropland of Guanzhong Plain from 1980s to 2015, this paper firstly utilized the dynamic degree and the position index to analyze cultivated land changes in different municipal administrative regions, and then used the grids of different scales to analyze the change trend and scale effect of the landscape pattern of cultivated land in Guanzhong Plain. Results showed that: 1) In the six stages of dynamic change of cultivated land, most administrative regions showed negative changes, except in Xi'an from 1980s to 1990 and in Baoji from 2005 to 2010. 2) During the study period, the cropland use in Weinan was the most intensive and the use intensity was kept strengthened. The intensiveness of cropland use in Xi'an was the lowest, and the reduction speed was accelerated, indicating the contradiction between the development of regional economy and the protection of cultivated land. 3) The total cropland area in Guanzhong Plain is reduced by “encircling”. At the same time, the distribution of cropland area index shows the characteristics of “encirclement” and the distribution of reducing area centered on Xi'an is “radial”. 4) At 1 KM * 1 KM grid scale, the aggravation and weakening of cropland fragmentation is characterized by mixed distribution, but with the increase of grid scale, the aggravation and weakening of cropland fragmentation are aggravated obviously and the degree of aggregation is aggravated.