GIS-based Analysis On Vegetation-Environment Gradient Correlation In Qinling Mountain

Qinling is the barrier between the north and the south of China, which has a distinct influence on climate. It is the borderline of Semi-tropic zone and Temperature zone in our country, and it is an important zone of vegetation distribution in the middle of China, in which there are complex sections, various types and vivid vegetation distribution characteristics. In the north of Qinling mountain, there distribute defoliation and broad-leaved forests, while in the south of it is northern Semi-tropic woods. In order to exploit and make full use of the forest, we should have a deep research on the various distribute of vegetation types and their rules to the protection and restoration of vegetation in Qinling mountain.Based on the relation of vegetation-environment, which is a hotspot in landscape ecology, vegetation quantity analysis methods and geography information system technique were applied. The research gave a multi-analysis on vegetation in Qinling mountain, and the correlation of different types of vegetation and five environment factors, including temperature, rainfalls, altitude, slope and aspect, is discussed. That will help to understand the configuration and function speciality of vegetation across-the-board, to master the general characteristics of vegetation distribution in Qinling mountain, and benefit to make clear the correlation and interaction of vegetation and environment. The research was done mainly as follow:1. Study on the correlation analysis of vegetation and environment gradientindicated: altitude gradient is the dominant ecological gradient to determine the vegetation distribution. Changes are taken placed with the increasing of altitude. The multiple gradient of water and heat are formed, corresponding types of vegetation transforms as well, functions slope and aspect do not play an evident function in separate.2. The results of CCA ordination made clear that temperature is the most important affection to vegetation in all environment factors. Axis 1 has negative correlation notably with temperature, which has positive correlation notably with altitude. It showed that axis 1 reflects the variation of altitude. Axis 2 has negative correlation with rainfalls, slope and aspect, but the correlation is not remarkable, rainfalls reflects theæµ·æ‹”and for water in the middle altitude of mountain partly, therefore it makes more sense than slope or aspect singly in ecology.3. The chart of CCA ordination reflected the configure gradient of vegetation clearly, along the axis1, the most types of vegetation transit from the cold plants, the cool plants, the mild plants and the warm plants to semitropical plants. According to it, all of the vegetation were divided to seven species groups, opened out the important environment gradient and the very growing environment characteristic of each type of species groups further.