The Research On Population Carrying Capacity Of Mountain Ecosystem--A Case Study Of Long Dong Gou Watershed In Mao County

Since human entered in modern times, the population's quick increase makes the contradiction between the infinity of the population's need and the limit of natural resource's renewal ability and the environmental endurance acute. Every country in the world widely researched on population carrying capacity, and human has researched on this problem for several hundred years. Mountain ecosystem plays an important part in human's living environment. On the base of trailing the theory and method of research on population carrying capacity, the paper does research on the population carrying capacity in mountain ecosystem from two aspects of theory and practice, and introduces system dynamics.In the aspect of the theory, first on the base of the definition of population carrying capacity and mountain ecosystem and summing-up the characteristic of them, the definition of population carrying capacity of mountain ecosystem are given. It is the appropriate amount of population in favor of the mountain ecosystem's sustainable development, the structure of the human's ecosystem and human's standard of living being considered. It has the character such as dynamics, area's difference, basing on agriculture ecosystem, the size being decided on the output of the economy system in the area, many conditioning factors,-uncertain parameter, and so on. The influencing factors are natural resource, agricultural structure, population and traffic. Second since system dynamics is the new method of research on population carrying capacity,the paper introduces this method and considers that it is the rational and feasible way of research on population carrying capacity of mountain ecosystem.In the aspect of practice, a particular analysis on Longdong Gou watershed in Mao County is given. The watershed includes Longdong village and Huilong village. The actuality of the watershed's nature and social economy is analyzed. Then it is considered that there is fragility in its ecoenvironment and economy, and some dwellers' living environment is trial. Basing on the character of Longdong Gou's environment and economy, the paper sets up the population and agriculture system dynamics models of Longdong and Huilong village. The simulation and operation are done. Then the population amount and population carrying capacity in different time are obtained, contrasted and analyzed. The following conclusion is elicited: (1) there is over loading population problem in the agriculture system of Longdong Gou watershed, of which the problem is serious in Longdong village's agriculture system, but not in Huilong village; (2) changing the plantation to forest makes the plantation decrease, and the population carrying capacity reduces for a while, but the long-term benefit is good, and it is forecasted that the watershed's population carrying capacity will be changed from overloading to not overloading from 2008; (3) for resolving the problem of population overloading, besides the amount of population should be controlled, Huilong village should develop industries other than agriculture, and Huilong village should change the structure of farmer produce and improve the traffic condition.And the measures, which should be carried out to improve mountain ecosystem's population carrying capacity, are pointed out in this paper.