The Study of Land Use Evolution and Landscape Ecological Security Evaluation in Dianchi Lake Basin

The characteristics of land use evaluation and landscape ecological security pattern were analyzed based on Landsat remote sensing images in 1995, 2005 and 2015 to conduct research from 3 aspects of land use quantity change, spatial change and landscape ecological security of Dianchi Lake basin. The results show that from 1995 to 2015, the land types in the study area are mainly construction land, arable land, forest land and water area, among which the area of forest land, arable land and wetland decreases, the area of construction land and unused land increases, and the area of water area and irrigated land fluctuates; from 1995 to 2015, the arable land transferred to the research area was the largest, with a decrease of 46% in 20 years, and it was mainly converted to construction land. In 2015, the area of construction land increased by 1.6 times as much as that of 1995, mainly from arable land, wetland and forest land; from 1995 to 2015, the area of the study area was mainly higher security zone and medium security zone, and the average value of landscape ecological security index in the 3 periods was 38.16, 41.50 and 42.19, respectively, showing a slow growth trend of security level.