Based On Remote Sensing And Gis Technology Northeast Pastoral Ecotone Landscape Pattern And Change Research

Changling County, belongs to the typical region of farming-pastoral zone in northeast China and is chosen as a case study area in this paper. Base on the interpretation of the Landsat-TM data (with two digital images taken in 1980 and 2000, respectively), the landscape structure was studied by analyzing patch-size, spatial pattern, and other index to show the changing feature of landscape pattern. The results showed that:(1) From 1980 to 2000, farmland was always the matrix landscape in studied area. The obvious change in studied area was that grassland with high coverage reduced fast and farmland expended rapidly. The area of saline increased significantly. This indicated that besides the aggravation of salinity, the ratio of agricultural landscape was increased and the ratio of pastoral landscape was decreased.(2) There was grate difference in patch size during different landscape types. In the past 20 years, different landscape types had no obvious change in scales of landscape patch-size. In farmland, grassland with high coverage, grassland with middle coverage, grassland with low coverage, saline and unused area the larger patch was dominant. Otherwise the smaller patch was dominant in forestland and waters. The middle size patch was dominant in resident land. In farmland the larger patch became more and more and in grassland with high coverage the larger patch become fewer and fewer due to human activities.(3) Because of being influenced by human beings so strongly, the shapes of forestland and resident land's patch appeared regular; on the contrary, grassland with low coverage and saline was slightly influence by human beings, so the forms were complex and irregular. The shape index of farmland is biggest. During the 20 years, the shape index of farmland decreased, the one of grassland with high coverage increased and the one of other landscape had no obvious change. Analysis from the whole area the shape of landscape was becoming regular and simple.(4) The diversity index and evenness index decreased and the dominanceindex increased. This showed that the exploity by human beings was tendentious and the management was increasing, which improved the socioeconomic benefits of the region on one hand, but decreased the landscape diversity, leading to the decrease of eco-environmental benefits of some areas in the basin on the other hand. Human beings disturbed large patch into small patch so that the landscape was more fragmented.