摘要
生态位理论是生态学重要的基础理论之一。文章以生态位理论为基础,提出了耕地生态元和耕地生态位的概念,并对耕地生态位的特征、演替规律作了系统阐述。在此基础上,构建了用以量度区域耕地数量变化态势、方向和速度的数学模型——耕地数量生态位(宽度)及其扩充压缩度模型,并运用模型对焦作市1998～2004年期间耕地数量扩充压缩态势、方向、速度及其生态环境效应进行了分析。结果表明:(1)1998～2004年期间,焦作市耕地数量生态位整体呈逐年压缩趋势,且耕地数量生态位的压缩与林地和建设用地数量生态位的扩充直接相关,即耕地数量减少的主要原因是生态退耕和建设占用;(2)焦作市各县(市、区)耕地数量生态位压缩度相差较大,反映出焦作市耕地数量空间变化速度的差异性;(3)焦作市各年耕地数量生态位扩充压缩度均小于河南省耕地数量生态位扩充压缩度,表明焦作市各年耕地数量减少速度均大于河南省耕地数量减少速度;(4)焦作市耕地数量生态位的扩充压缩具有重要环境效应,并影响和制约着耕地生态背景质量和区域生态环境质量总体水平。
Niche theory is an important theory of ecology. This paper proposes the concepts of cultivated land ecounit and cultivated land niche, then expounds its chatacter and development law based on niche theory. The mathematical models of cultivated land quantity niche and its expansion-reduction-degree are constructed, which can measure the tendency, directiong and the speed of the change in the quantity of cultivated land. This paper analyses the features of the change in the quantity of cultivated land in Jiaozuo city during 1998-2004 by the mathematical models. The results are as follows： 1） the cultivated land quantity niche is reduced year after year in Jiaozuo city, and there is correlativity between the reduction of cultivated land quantity niche and the expansion of quantity niche of woodland and building land. 2） There are different expansion-reduction-degree of cultivated land quantity niche in every subarea of Jiaozuo city, which indicates that the otherness is much bigger among subareas in Jiaozuo city. 3） the cultivated land quantity niche expansion-reduction-degree of Jiaozuo city is less than the one of Henan province, which indicates that the reduction speed in the quantity of cultivated land in Jiaozuo city is bigger than the one of Henan province every year. 4） The expansion-reduction of cultivated land quantity niche result in environmental effect, which influence the ecological quantity and environmental quantity.
出处
《生态经济》
CSSCI
北大核心
2008年第9期37-44,共8页
Ecological Economy
基金
国家自然科学基金项目(编号:70773047)
国家“十一五”科技支撑计划重点项目(编号:2006BAB15B05)
国土资源部土地利用重点实验室开放基金(编号:08-01)
河南省软科学项目(编号:072400430810)
关键词
耕地生态位
扩充压缩度
土地功能性用途
生态环境效应
焦作市
cultivated land niche
expansion-reduction-degree
land functional use
ecological environmental effect
Jiaozuo city
