生态位适宜度方法在基于GIS的耕地多宜性评价中的应用

以江汉平原后湖地区耕地为研究对象，将生态位适宜度方法引入到多宜性评价研究中，采用加权平均和限制因子模型对各评价单元水稻、小麦、棉花和油菜4种作物的生态位适宜度值及限制因子进行了定量分析。结果表明：研究区生态位适宜度值整体较高，最大值达0．958，生境条件基本能满足作物的需求；评价结果以1、2级为主，所占面积达75％；水稻的适宜性面积在该区最大，达65．54％，小麦次之；限制该地区耕地生产潜力的生态因子主要为：速效磷、CEC和道路通达度。该研究结果能直接指导农业生产实践，促进耕地的合理利用与管理。

NICHE-FITNESS THEORY AND ITS APPLICATION TO GIS-BASED MULTI-SUITABILITY EVALUATION OF CULTIVATED LAND

With the theory of sustainable development as guide for the agriculture of China, farmland in Houhu region of the Jianghan Plain was selected for case-study on introduction of the niche-fitness theory into multi-suitability evaluation of cultivated land. Quantitative analyses of niche fitness of and restrictive factors for rice, wheat, cotton and rape, were carried out by means of weighted average and limiting factor models. The results indicate that the niche-fitness value in this area is in medium on the high side with the peak value reaching 0. 958, suggesting the region meets the basic requirements of the crops ; and farmlands in Grade 1 and 2 account for 75 % ; rice ranks first in terms of acreage of niche-fitness, amounting to 65.54 %, and wheat comes the next. CEC, soluble phosphorus and accessibility to roads are the primary niche factors that restrict land productive potential in this area. These results of the study can find direct application to supervision of agricultural production, to reasonable utilization and scientific management of cultivated land resources.