Abstract: Researches on species extinction caused by the shrink or loss of habitat are one of the hottest points of biological study, in which numerous biological scientists have been involved. The Tianjin Qilihai Wetland was set to example to simulate the mechanism between habitat destruction and species richness. This research combined theoretical research with numeral simulation and set up the evolutional model of exponent upon the effect of human activities. 1) The exponent value of dis 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. When the condition of d<1 is met, the effect of environment on meta-population is beneficial 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. 2) The third mechanism of extinction of meta-population, the coordinate law of evolution and degradation of species in the restoration of destruction habitat are also found, which is the same evolutional trait of different species. The evolutional law between the restoration and destruction of habitat has same points and differences.

Key words: meta-population, remnant environment volume, nonlinear dynamic model, Tianjin Qilihai wetland

摘要： 采用理论研究与实践检验相结合、理论分析与数值模拟相结合的方法，提出了环境容量变化对物种多度影响的模式，以天津七里海湿地为例，研究了集合动物种群的演化特点、物种灭绝的顺序与环境容量变化的关系。从理论上揭示了：1)当幂指数小于1，环境对集合种群的作用有利于其发展时，栖息地的破坏导致物种灭绝数目较少；当幂指数大于1时，剩余环境容量变小将导致最强及比它弱的若干物种灭绝，指数越大物种的灭绝数就越多。剩余环境容量越大，弱物种就越能在激烈的竞争中幸免灭绝；环境容量越小，弱物种面临灭绝的可能性就越大。2)物种的第三类灭绝机制和物种的协同进化、协同退化规律，反映了真实生态系统的复杂的灭绝情况。

关键词: 集合种群, 剩余环境容量, 非线性动力模式, 天津七里海湿地