LUCC And Dynamic Evaluation Of Ecology Security In Weinan City

Land Use and Land Cover Change (LUCC) holds the important status in the whole world environmental variation and the sustainable development research, and population quantity affects directly the Land Use and Land Cover Change. In our country ecological environment foundation is frail, and the huge population pressure and unreasonably developing the resources and the light consciousness to the ecology security have had the huge and lasting pressure to the environment. The problem of ecology security has already become a major issue that affects our country's security, especially in such ecology resources as national territory resources and water resources. The evaluation of regional ecology security is one of the main research contents on ecology security. Through securely attributing and quantitatively evaluating the condition of the ecological environment system, the public's understanding for the serious situation of the ecological environment question is deepened, the ecological environment management and the ecological environment construction become even more concrete and feasible, and the ecological environment regulation has the quantificational significance. Therefore, the evaluation of regional ecology security has the extremely important theory and practical significance to the development of the regional society and economy. In this paper uniting the fund project of country's natural sciences, the author has conducted the research and practice to the change of the regional ecology security.Shaanxi Province is located in the northwest ecology frail area of China, the geographical position is special, and the natural condition is complex. Weinan city, whose agricultural development is especially swift and violent, has become an important agricultural industry area of grain, cotton, fruit and so on in Shaanxi and even in China, named " Shaanxi Granary" . It is Shaanxi Province's east front door, and during the development of the west of China is a connecting link between the east and the west. But in the recent years, with the rapid development of the social economy, the ecological environment quality is worsening and in the local area ecology security condition receives the serious threat, which already becomes the important factor to restrict the sustainable development of the society and economy. Through scientifically analyzing and appraising the present situation of ecology security in this region, theunderstanding to the ecology security condition in Weinan is deepened, and the theory, method and evaluation model are provided for the research of the similar areas.The paper are altogether divided six parts: In the first part the land utilization change, the ecology value computation as well as the research background, the research progresses and the research significance of the ecology security evaluation and the problems in the research are summarized. In the second part the researched areas have been analyzed and chosen and the overall mentality of the research has been proposed. In the third part the change situation of land utilization in recent years in Weinan city has been analyzed and researched from the variation rate of land utilization, the change of land utilization degree, the change situation of land utilization per person and so on. In the fourth part the change situation of ecology value in recent years in Weinan city has been studied. Except for using the traditional method, the ecology value per person in this region has mainly been discussed. The relations among total ecology value, ecology value per person and population have been analyzed, and the inner link between the environment pressure and the population has been promulgated. At the same time the regional differences of the environment pressure have been analyzed. In the fifth part the ecology security in Weinan city has been appraised dynamically, and the change situation and mechanism of ecological environment pressure, ecological environment quality and ecological environment renovating and construction ability has been analyzed. At the same time, the development direction of ecology security in Weinan city has been promulgated. In the sixth part the research conclusion has been proposed.The findings indicated that during 1996-2004, in eight kinds of land utilization types of Weinan city, the decrement of the cultivated land is the biggest, which is 18663.18 hectares, and in the types whose area assumes the growth tendency the increment of the forest land is the biggest. The change of land utilization has the remarkable region differences in the spatial distribution in Weinan city. In Weinan city the yearly total quantity of service value of ecosystem is increasing continuously in 1996-2004, but its change of service value of ecosystem has obvious region differences. At the same time, because population grows excessively quickly, the service value of ecosystem per person does not increase along with the yearly total quantity of service value of ecosystem increasing. At present, the service value of ecosystem per person Weinan city has already reduced from 1202.96 Yuan of 1996 to 1185.38 Yuan of 2004. This explains sufficiently the yearly total quantity of service value of ecosystem in aresign cannot reflect the ecological environment pressure, and ecological environment pressure and the year total quantity of service value of ecosystem have not a proportional relationship. The quantity of population during these eight years is also growing fast in Weinan city. Because the increase of the yearly total quantity of ecology value cannot make up the ecological environment pressure that the population increase creates, the ecological environment pressure is increasing continuously.However, under the influence of the policy of west development and substituting the agricultural land for the forest and grass, the environment quality is enhancing year by year in Weinan. The social economy is developing fast, and the ability of the government's investment and transformation construction to the environment ability is enhancing year by year. Synthesizing the above three and using the theory of region ecology security and the analytic hierarchy process, the author calculated relative ecology security index of Weinan city in 1997-2003 and promulgated its ecology security condition. The result indicated that the ecology security index of Weinan city is increasing year by year, already increasing to 0.391 of 2003 from 0.267of 1997. The bigger the ecology security index is, the safer the ecological environment is, and vice versa. This explains the ecological environment safety is enhancing gradually in Weinan city during 1997-2003. In Weinan city in 1997-2003 the ecology security indexes are all bigger than 0.25 and smaller than 0.50, which belongs to the very unsafe condition, but during these five years the ecology security index is enlarging year by year actually, namely the ecological environment is developing to a safe direction.The characteristics of this paper are follows: Weinan city is chosen as the researched area which people don't pay attention to but is extremely important to Shanxi Province. The concept of service value of ecosystem per person was proposed, using which the change situation of ecological environment of Weinan city was analyzed and the intrinsic mechanism of the change and the reason of regional differences were promulgated. The ecological environment pressure, ecological environment quality and the environment renovation and construction ability of Weinan city had been appraised dynamically on the space and time, and the reason had been analyzed. The ecology security of Weinan city had been appraised dynamically, and the intrinsic reason of its change had been analyzed.