彭州市耕地数量和质量时空变化分析

根据2000～2006年彭州市耕地统计数据,应用土地利用动态度、土地利用变化区域差异模型和GIS方法研究了耕地资源数量和质量的变化特征。结果表明,彭州市耕地以灌溉水田及旱地为主,且受地形地貌和区域条件的影响,空间分布差异明显。6年间研究区耕地面积基本持平,但不同年份间差异较大。耕地土壤中其有机质、全氮、全磷和速效磷的含量升高,但土壤中的重金属含量也在普遍升高,且土壤中氮、磷的增加从一定程度上看是大量施用化肥的结果,其本身也是重要的有机污染物质,因而,经综合分析,可以认为彭州市耕地的整体质量是处于一种下降的趋势。

Analysis on the Spatial-temporal Variation of Farmland Quantity and quality in Pengzhou

According to the statistical data about the farmlands in Pengzhou from 2000 to 2006,the variation features of its farmland quantity and quality are studied by using land use dynamics model,the regional variation model of land use change and GIS.Results indicated that,most of the farmlands in Pengzhou are irrigated paddy fields and dry lands,which are affected by landform and regional conditions,presenting a significant spatial distribution.The farmland area in the studying area remains basically stable during the six years,but varies largely in different years.The contents of organic matter,total N,total P and available P in soils increase,and the heavy metals content also presents a general increasing trend,the increase of N and P in soils is caused by a large quantity of fertilization to some extent,and N and P themselves are also main organic pollutants,therefore,it is concluded from comprehensive analysis that the overall quality of farmlands in Pengzhou shows an overall decreasing tendency.