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Certain effects of human activities on species diversity preliminary study

Author: XieZhengLei
Tutor: LinZhenShan
School: Nanjing Normal University
Course: Physical Geography
Keywords: meta-population habitat restoration extinction nonlinear dynamic model
CLC: Q14
Type: Master's thesis
Year: 2005
Downloads: 357
Quote: 7
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Abstract

The hot spot in the field of environment and ecology are about: how the fragmentation of habitat affects the survival and extinction of single or multi-species in fragile environment? How do species evolve along with the change of environment? What is evolutional trait of species and dynamical response mechanism of transformation of landscape, condition of obligation and forecast under the effect of human activities?The dynamic of meta-population is not only a significant frontiers in recent newly-developed of spatial ecology, but also a new hotspots in mathematical ecology. The dynamical model of meta-population can be researched the dynamical aftermath of individual migration and evolution of local population when habitat has been destructed, fragmented and restorated.The paper combined theoretical research with field test, theoretical analyze with numeral simulation and integrate traditional ecology, geographical science, geographical ecology with complex science and set up the evolutional model of different meta-population upon the effect of human activities. Based on the model of Logistic, Levins and Tilman, the model of exponent, restoration of habitat,habitat overlap has been put forward systematically and probe into the following questions :how do the evolutional characteristic of meta-population in different regions, the relation between the extinction order of animals and the degree of habitat destruction upon by human activities. Does habitat restoration will cause species extinction?The innovation point of this paper is that we have put up some models, such as the model about the restoration of habitat, exponent model, and overlap of habitat. We put forward the introductive research between the human activities and the diversity of species and the results obtained in the paper is useful to enrich the content of landscape ecology and the protection of endangered species.The dissertation revealed some results from the point of maths and physics:(1) As for multi-species coexistence system suitable for certain changes of environment, any changes, either destruction or restoration of habitat would inevitably disturb the balance. Our study shows the dominant species in any community can persist and are free the threats of extinction in habitat restoration. Some sub-strongest species will reach a new equilibrium along the evolution process of thousands of years. As for most of species in habitat, the restoration of habitat is avaiable for the survival of species. However, it is not a good for some sub-strongest species.(2) The exponent value of d is defined as the coefficient value of the interaction between species and environment and it can be applied to research the evolutional mechanism of different meta-population. The evolutional traits of meta-population are different along with different effect of environment. When the condition of d < 1 is met, the effect of environment on meta-population is benefit to the development of species and habitat destruction will not lead to species extinction. While the condition of d > 1 is met, the strongest species will be driven to extinguish owing to the decrease of content of habitat and the system will reach new state in a short time. The bigger the value of d is, the shorter of time system reach new state is. The results show that the survival and development of species is sensible to the change of volume of environment.(3) The coordinate law of evolution and degradation of species in the restoration and destruction of habitat is also found in the paper, which is the same evolutional trait of different species. The evolutional law between the restoration and destruction of habitat has the same points and thedifferent points.

Certain effects of human activities on species diversity preliminary study

Abstract

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