Study On Landscape Pattern Change And Ecological Security In Jinghe County

The environment is very easy to destroy in northwest of China. How to harmonize the relation between water-enviroment-economy and make human and environment sustainable development is always one of the most important issues. The paper takes a typical region in arid zones-Jinghe county as an example, bases on landscape theory and 3S technology, analysis the study area's LUCC, Landscape pattern Change and Ecological Security in a certain period.This paper uses 3S technology in macroscopic. The author uses pixel change detection method to acquire the LUCC region, analyses LUCC transfer and dynamic change at first. Secondly, based on the theory of landscape ecology, heterogeneity, spatial scale and natural level, the author chooses 14 index of landscape to analysis the change of landscape in patch class level and landscape level. At last, the author sets up a regional ecological security evaluating system based on LUCC, landscape change, social economy and the frame of PSR-AHP. The author also brings forward a method of ecological security evaluating, which could confirm the index, the value of index and the weights of index. We also give a evaluation of ecological security in Jinghe county especially in 1990, 2001 and 2005 .The conclusions are as follows: The trend of LUCC is that the area of oasis expends slowly in nearly 33 years between 1972 to 2005 in Jinghe county. While the area of human oasis expends fast, the area of natural oasis decreases. It is the area of farm land and human forest land increasing while the grassland decreasing in class. It is exactly influenced by the increase of population, the degree of open up wasteland and policy of reclaiming forest and grass in 1990s. The area of water area is mainly influenced by Ebinur lake, so the area expends a little in this period. The area of Salinization land expands at first and reduces later. Its area is largest in 1990 and decrease largely in 2005. The area of sand land decreases and the other land class increases while the probability of transfer is always high. The rate of LUCC is high in the 33 years, the index of comprehensive land using dynamic change degree is 2.23 % and the velocity of farmland change is highest in all. The period in the middle is higher than others two periods. The Jinghe county oasis mainly expends at the edge of oasis and the area of hungriness decreases.Landscape change is also obviously in the decades. Totally, landscape density increases, the largest path index decreases at first and expends later, the weight area index decreases and the shape of landscape becomes regulation. The nearest distance, the degree of reunite and outspread decreases. It shows that the connection of mainly path in 1972 is better than 2005, the patch becomes more complexity. From the change of Shannon's Diversity Index and Shannon's Evenness Index, we know that the diversity of landscape and the Interspersion_Juxtaposition Index increase. The degree of diversity landscape and fragmentation increasing also shows that the land use become more complex. The reason of the change is that human activity influenced the path, the substance, energy and information stream changes, so the landscape pattern changes, the index of fragmentation and diversity increases too. At the inner of oasis, the patch complexity influenced by the level of agriculture, the CONTAG increases either. At the edge of oasis, the area of farmland expends, so the shape of landscape becomes complexity and the scrambling increases.The author analyses the ecological security in 1990,2001 and 2005, bases on the frame of PSR-AHP and get the index of ecological security is 0.5230,0.6438 and 0.5962 respectively in 1990,2001 and 2005. It means that the total ecological security trendy is good, but it has some flutters in certain period.The target of the study is to research on the ecological security influenced by LUCC and landscape pattern change in Jinghe county after opening and reforms for more than 30 years. It could also give the local government a reference decision for environment construction.