The Space Change Of Landscape Pattern And Ecological Environment Significance During Recent 15 Year In Yitong River Basin

YiTong river is the only river flows through the hinterland of jilin province , It basin in the middle of the SongLiao plain located in JiLin province, the area is 8440 square metre. For such a special area landscape pattern analysis, strengthen the whole watershed ecological protection, environment optimizing etc is has the extremely vital significance.Through the image preprocessing and landscape pattern change analysis, combined with natural and human factors to understand nearly 15 years the spatial distribution of different types of the landscape and the development variation characteristics of ecological environmental impact of degree. Some conclusions:(1)According to the annual YiTong river basin in remote sensing image data for registration, calibration, boundary extraction and image enhancement processing . Get 1993, in 2001 and 2008 YiTong river basin landscape classification figure. Through comparing the three years that changes of plaques contrast : In the whole landscape type, the majority of dry land has been increasing and show the trend of paddy fields, forest land, water was gradually transferred to the dry land, and the area is declines in the study area, residential areas, the distribution of relatively scattered throughout the study area of the area proportion also show a faint rise.(2)From the research area landscape elements type level index analysis of the results, which can be seen from 1993 to 2008, each landscape type plaques are shape index between between 1.0-3.2. From 1993 to 2008, the landscape elements plaques shape index woodland, residence changes except the relatively large outside, other types of land small changes shape of patch index. The landscape pattern changes overall relatively alleviation, variation amplitude is not very big. 1993 to 2008, the extent of landscape fragmentation have declined overall, landscape diversity index changes amplitude is larger, but overall situation for increased changes, including landscape diversity is the highest in 2008.(3)from ecological safety calculated value view, the size of the research area whole ecological safety degree 0.685 0.699 from rose, regional ecological security improved. In three research point general ecological safety, study area were in the general condition.