Abstract:

The Nichefitness theory is a further development of the classical niche theory and an extension of the related methods.The nichefitness model developed on the basis of niche can reflect the fitness degree of crops to environmental conditions relatively well.It can also be utilized to analyze factors restricting the growth of crops.However,there is little work on suitability evaluation especially multisuitability evaluation on tillage by applying the nichefitness theory.Under the guidance of the theory of sustainable development for Chinese agriculture,this paper aimed to use nichefitness model to assess suitability degree and limiting factors of garden land in Yiling District of Hubei Province in China.Firstly,the index system of suitability evaluation was established including 5 subgoals and 12 indices.Then,in order to normalize the measured value,indicators were categorized into numerical type,linguistic type and spatial diffusion type according to their attributes.After constructing the suitability evaluation models,the degree of suitability for garden land was classified into 4 levels,where the nichefitness value ranged from 0372 to 0893 with a maximum of 0893;one level and two level were predominant portions with their areas accounting for 6292 percent of the total.Four level with lower suitability and quality accounted for 643 percent of the total.The soil texture,average temperature of the coldest month and accessibility of road were the primary limiting factors and important issues of agriculture management.The results can be used as a quantitative basis in evaluation of garden land quality and resolution of the land reasonable utilization in this region.On the other hand,the research can extended and deepened theory and methodology of traditional land suitability evaluation subject