Analysis On Sustainability Of Oasis Agro-economic System Based On Emergy Theory

The oasis has coupled with the abundant water resources in mountain area from the upper course , favorable light-thermal resources from the down course, and formed complex, unique agro-ecosystem. This agro–ecosystem has become the center for the natural resources, population and economic development of arid area. Tikanlik is an oasis which located the down part of lower reaches of Tarim River and has owned dense population and modernized agriculture. Because the dry-up of stream flow of Tarim River, and the high intensity of human activity, the agro-ecosystem's security of Tikanlik oasis was threatened, oasis agriculture economy couldn't develop fast and the life standard of people whom live there also couldn't get better. How to keep the balance between the natural resources, environment and social economic development, and how to realize the sustainable development of oasis agro–economic system, under various unfavorable conditions, has been taken the serious attention of scholars and government.In this thesis, based on the meteorological and social economical data of Tikanlik oasis from1996 to 2007, applied the emergy theory and method, analyzed resources composition, structure, working efficiency, and social economic development level from the current emergy status and dynamic emergy changes aspects, and also discussed the effects of natural resources utilization and human social economic activity on the sustainable development of oasis agro–economic system. Study results showed that:1. From the period of 1996-2007, the total emergy input and total emergy output of Tikanlik oasis agro-economic system presented increasing trend, among them, main input items of non-renewable resources are machinery, electric power and chemical fertilizer, etc. The chief input item of renewable resources is irrigation water, and the input amount of this item has close relation to do with those can be supplied it from the outside of River. The crop plantation has absolute predominance in total emergy output, and the changes of emergy output in forestry and animal husbandry appeared to unstable. In recent years, the predominated position of crop plantation has become more obvious, and the development of forestry and animal husbandry were still weak.2. By analyzing a series of emergy indexes it can be seen that the incremental output of agro-products was gained at the cost of high rate of investment and high energy consumption.Although this mode accelerated the social economic development and raised people's living standards to some extent, but this way of resources utilization had negative impact for keeping the sustainability of the agro-economic system. Additionally, because of the low efficiency of operational system, and people's blindly use of natural resources for get more economic benefit, had lead to the downgrade of agro-economic sustainability of this area. The internal productive structure of oasis agro-economic system showed unbalance and is getting more and more obvious in recent years. The crop plantation occupied high proportion and its structure was single, as a result the self-adjustment ability and stability of system were fragile. In contrast, the stability of forestry and animal husbandry were batter than crop plantation, but their development status was still rather weak.3. According to the study results and actual status of agro-economic system in Tikanlik oasis, following countermeasures had been put forward to giving the right direction for the future development of this study area. Such as: persist in developing water-saving agriculture in oasis and rational use of land resource; control industrial sub-energy input and enhance organic fertilizer input; develop science and technology, improve human agricultural production efficiency; optimize and adjust the agricultural structure; accelerate agricultural product processing, and promote the industrialization of agriculture. These measurements could be useful for promoting the sustainable development of Tikanlik oasis agro-economic system.