The Effects Of Niche Construction On Prey-Competition System

Niche construction is the ability of organism throngs their select, activities and meta that modify its local important environments, consequently modifying their both biotic and abiotic sources of natural selection in their environment. The key of niche construction is the feedback between organism and environment in evolution. As a result, the evolution is the product of interacting processes of natural selection and niche construction. The classical evolutionary theory was extended with niche construction. It provides novel theoretical grounds for species adaptation and also offers the rational mechanism for explaining many ecological phenomena at different scales.In the dissertation, we highlighted the new focus in this field:the effect of niche construction on prey-competition system. Prey-competition system is the basic and typical system in ecology environment. Through studying the effect of niche construction on the species number and spatial distribution of this system, we would make progress on niche construction theory. Two approaches will be utilized in the study. One is the differential dynamical system. I am using the phase plane analysis and numerical solution, the equilibriums and their stability of the system will be illustrated. This approach can show the temporal dynamics of species. The other is the spatially explicit model of reaction-diffusion equation, By the software Matlab, spatial pattern, structure and dynamics will be explicitly demonstrated, which can make up for the deficiency of spatially implicit model.The dissertation will be separated into four chapters:Chapter one will summarize the frontiers and development of niche construction, as well as the concepts, theories and simulation approaches that will be used in the following. Chapter two will construct the differential dynamical system, and discusses the effect of niche construction on the temporal dynamics of prey-competition system through analysis the result of the model. Chapter three will construct the spatially explicit model of reaction-diffusion equation, and discusses the effect of niche construction on the spatial distribution of prey-competition system through analysis the result of the model, will analysis the result of the two models, and discusses the effect of niche construction on the species number and living space change of this system. In the last chapter, I make the main conclusions and the perspectives about the niche construction development.Three results and conclusions are obtained in this dissertation. (1) niche construction did not destroy the stable of prey-competition system. (2) niche-constructing could enhance its own competitive strength and also maintain the system balance in adverse environments.(3) niche construction has the potential to improve a diffusivity of niche-constructing species, which promote them to immigrate for more suitable habitats and hence become a stable species of system.(4)Because of the limit resource, the niche construction and diffuse will conform to the trade-off relation, the relation will limit species spread range and maintaining the balance.