北京山区耕地质量变化及未来趋势模拟

Cultivated land quality change and its future trend modeling in Beijing mountainous area

准确把握区域耕地质量现状、空间分布以及未来变化,对实现耕地保护由数量平衡与管理向数量-质量综合平衡与管理具有重要意义。应用GIS空间分析与模拟技术,在对北京山区耕地质量进行定量评价的基础上,对山区不同地域层次上的耕地质量变化及未来趋势进行了分析。研究结果发现,1993-2004年北京山区以及各地貌类型区域耕地质量处于总体提高态势,耕地质量的提高主要是耕地布局优化的结果。2004-2015年,北京山区耕地总体质量将继续提高,但总体幅度有所减小;同时,不同区域耕地质量变化出现分异,山区和半山区耕地质量仍然不断增加,平原区耕地质量则出现了降低现象。未来耕地保护工作中,要把耕地布局优化作为保护与提高耕地质量的重要手段,注意选择新增耕地的立地条件,保证新增耕地质量;并统筹考虑耕地数量保护和质量保护,在不断提高地力的同时,通过经济手段的实施来加强耕地质量保护。

This paper analyzed the cultivated land quality and its future trend on the basis of cultivated land quality evaluation,which is of great significance to realize the managements of cultivated land from emphasizing on its quantity unilaterally to on its quantity and quality comprehensively.Methods of GIS spatial analysis and scenario modeling by CA-Markov model were employed.The results indicated that cultivated land quality took on an increasing trend both in mountainous area as a whole and three types of physiognomy areas from 1993 to 2004,and the trend was got mainly by the optimization of cultivated land layout.Moreover,from the result of scenario modeling,the cultivated land quality continued to increase from 2004 to 2015,but the increment got smaller.Also the cultivated land quality change became to differentiation at different types of physiognomy,where the quality increased at mountainous area and semi-mountainous area while decreased at plainous area.In the future,some measures should be carried out to protect and improve the cultivated land quality.Firstly,the layout optimization of cultivated land should be looked as an important way to protect land quality besides the fertility increase.Secondly,the site plot of newly increased cultivated land should be examined carefully to guarantee its quality.Thirdly,the quality protection and quantity protection should be considered as a whole,and the economic methods should be implemented to reinforce the quality protection of cultivated land.