基于生态位理论的耕地可持续利用评价

Evaluation of sustainable use of cultivated land based on niche theory

基于生态位理论和前人对耕地可持续利用的认识和理解,从理论层面浅析了两者在本质上的一致性;尝试从生态位理论的视角去理解耕地可持续利用的内涵,从而利用生态位适宜度来定量测度耕地可持续利用水平。具体在以往生态位适宜度模型基于现实生态位与理想生态位之间"绝对距离"的测度思路之上,融入生态元现实生态位与相邻生态元之间"相对距离"对生态位适宜度影响的考虑,重构生态位适宜度模型。从耕地的自然、经济、社会三大属性层面,选取指标建立耕地可持续利用评价指标体系,以吴川市为研究对象的结果表明:镇级尺度上,耕地可持续利用处于中等水平;耕地自然、社会、经济可持续利用水平在空间上具有不同的分布特征,且空间差异性依次逐渐减弱。生态位理论和生态位适宜度模型的引入,为耕地可持续利用的内涵理解及其定量评价提供了新的认识论和方法论。

Based on the niche theory and the predecessor＇s conception or comprehension about the sustainable use of cultivated land, the author analyzed the consistence of them from the point of essence. Trying to had a deep understanding of the connotation about the sustainable use of cultivated land from the view of niche theory, and utilized the niche-fitness to measure the sustainability of cultivated land using. The research method in the paper stood on the calculating idea of previous niche-fitness model which measured the ＂direct distance＂ between the real niche and the optimal niche, the author also thought over the impact of ＂relative distance＂ which between the eco-unit＇s real niche and the neighboring eco-unit, and rebuilt a new niche-fitness model. Selected index from the natural, economic and social attribute of cultivated land so as to set up the new evaluation index system, and launched an evaluation about the sustainable use of cultivated land in Wuchuan city. The results of the paper suggested that the sustainability of cultivated land in town-scale was in medium level; the space distribution model among the natural sustainable, social sustainable and economic sustainable over cultivated land using were different, and the space disparity successively reduced by degrees. The introducing of niche theory and niche-fitness model offered a new epistemology to acquire the connotation about the sustainable use of cultivated land, and a new methodology to measure it.