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发表于 2007-6-29 23:16:41
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Abstract
Nowadays China is facing with an unprecedented large population and more and more serious threat of natural resource deficiency. So the issue of the land carrying capacity is concerned by increasing people in our country. The dissertation probes the research method of the land-population carrying capacity in the irrigating farming zone of the typical arid region according to the local specific conditions. Beginning with the utilization of the land, this paper uses the knowledge of population economics, land economics, resource economics, environment economics, mathematical statistics and forecasting & decision theory to predict the land demand scientifically, reasonably and systematically. The article makes a quantitative analysis based on the qualitative analysis. After calculating the potential productivity of the crops in the oasis, it forecasts not only the future population, but also the land demand and the land-population carrying capacity. Meanwhile it analyses the balance relationship between the land demand and the quantity of various land at present. Hence, it draws a conclusion that the land carrying capacity in Xinjiang will have a small favorable balance in 5 to 45 years. In the end, the writer gives some suggestions which can help to raise the potential productivity and enhance the land-population carrying capacity and provides some ways to protect the ecological environment.
The whole research includes three parts.
The first part includes chapter 2 and chapter 3. Chapter 2 introduces a series of basic relative theories and methods about the land carrying capacity. Starting from the basic conception of the land, it goes deep into the connotation and features about the land carrying capacity after presenting the land sustainable utilization theory. It also outlines the researching development of this topic. Therefore, the above makes a theoretical preparation for the coming study. Chapter 3 focuses on the research methods. This paper systematically explains quite a lot of models which centres on land productivity. The application of the systemic dynamics and the comprehensive forecasting model are also stated in this part. All these work has prepared for the following empirical study.
The second part, chapter 4, firstly explains the present situation of the land carrying capacity in Xinjiang, especially shows the land feature, the utilization and the developing trend. Because of the important relationship between the water resource and land , the thesis expresses the current conditions and characteristics of the water resource on purpose.
Then, it calculates and analyses the land carrying capacity concretely. Since the population is one of the cores of this problem, the treatise uses a few of methods to forecast the immediate-term, medium and long-term population, and ascertains a scale of population in Xinjiang according to the different accuracy of these methods. Then it predicts the unit production and total output of the main crops in Xinjiang with the sectional comprehensive model combined with the inclination’s extrapolation. After calculating the crops’ potential productivity based on the sunlight, the temperature and the climate, the article forecasts the land demand of the main crops and the construction in Xinjiang. The analysis about the future land carrying capacity is made from the above calculation. It needs to pay attention that the paper also makes a prediction about the expense of the water resource to make sure of a good match between the land and water.
The third part, chapter 5, analyses the existing problem and gives some advice. Firstly, the writer points out the beneficial factors which can enhance the land carrying capacity,. These factors include a big quantity of potential land for exploring, the large amount of water resource and plentiful sunlight and heat resource. The adverse factors are the harsh natural condition, the uneven distribution of the time and the space about the water resource, the backward facilities of water conservancy, low efficiency of the water and the land utilization, the shortage of capital and technology, and the fast growing population. On the basis of the above factors, the paper gives some advice and measures to enhance the land carrying capacity in the end. We should firstly fasten the economic development to contribute a firm economic base for the land usage; secondly enhance the efficiency of the water utilization; thirdly improve the agricultural technology; fourthly make an intensive operation to the land and fifthly control the population under a reasonable level. |
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