丘陵地区中小城市城乡结合部土地利用变化特征*——以内江市四合乡为例

CHANGES OF LAND USE IN RURAL-URBAN CONTINUUM OF HILLY REGIONS*——A CASE STUDY IN SIHE TOWNSHIP OF NEIJIANG

关键词:  分形理论土地利用城乡结合部丘陵地区内江市四合乡

Key words:  fractal theory  land use  urban rural continuum  hilly region  Sihe township of Neijiang city

摘要:

［目的］探究城乡结合部土地利用方式在城市急剧扩张过程中的变化特征，对统筹城市产业布局和城乡一体化发展具有重要意义。［方法］文章以2009年和2014年内江市城乡结合部的四合乡土地利用数据为研究对象，利用分形理论和景观生态学方法，分析其一级地类分维数、数量及空间分布变化。［结果］四合乡土地利用数据具有分形特征， 2014年与2009年相比，分维数值由1267~1612缩小至1170~1463，除园地外，其余地类分维数值均呈下降趋势，各土地类型轮廓更趋规则； 5年间多种土地利用类型快速更替，面积增减明显，主要表现为耕地大量减少，交通、建设用地明显增多，园地、林地、水域缩减较少，其他土地类型有少量增加。［结论］在乡镇尺度上，城乡结合部受其区位和城市布局共同影响，耕地被建设用地大量侵占，造成农用地减少； 因农村劳动力向城市转移，亦有耕地被撂荒现象。该研究结果可为类似区域土地资源管理提供实践参考。

Abstract:

For the overall planning of urban industrial layout and the integrated urban rural development, it is of great significance to explore the changing characteristics of land use patterns in the process of rapid urban expansion in the urban rural continuum. Taking Sihe township in the urban rural continuum of Neijiang city as an example, based on the land use data in 2009 and 2014, the fractal theory and landscape ecology method were used to analyze the changes in the fractal dimension, quantity and spatial distribution of the first class land. Land use data of Sihe township were featured with fractal characteristics. In 2014, compared with 2009, the fractal dimension value decreased from 1.267~1.612 to 1.170~1.463, and the contour of all land types gradually became regular. Except for the garden land, the fractal dimension value of other land types had a downward trend. Meanwhile, in the past five years, many land use types had changed rapidly and the area had increased or decreased significantly, which mainly reflected in a large reduction in cultivated land, a significant increase in traffic and construction land, a small reduction in garden land, forest land and water area, and a small increase in other land types. The cultivated land is occupied by a lot of construction land due to its location and urban layout, resulting in a reduction of agricultural land. Due to the transfer of the rural labor force to cities, some cultivated land is abandoned. The conclusions of this study can provide practical reference for land resource management in similar regions.