Dynamic Analysis Of Landscape Pattern And Functional Types In Ansai District,Yan ’an City

Landscape is a natural surface complex with a high degree of spatial heterogeneity.The overall structure of the landscape and the time change process are relatively slow.Under the influence of many natural and human factors,different factors of the landscape influence each other on a large scale of time and space.Eventually lead to changes in regional landscape patterns.Based on Landsat TM remote sensing image data in 2005 and2016,the landscape pattern and functional types of the research area were analyzed by using RS and GIS techniques.Through the change of landscape pattern between different years,we can fully understand the change of landscape pattern in the regional ecological function zone of Yan ’an City on the time scale,and clarify the driving factors of the change of landscape pattern in the region.The results of the study indicate that:(1)The landscape status quo shows that the landscape type has not changed,the number of patches has increased,the density of patches has increased,the edge density has increased,the edge length has increased,the fragmentation index has increased,and the aggregation index has increased,and the degree of landscape fragmentation has gradually increased.(2)Forest landscape is dominant in the landscape pattern of the entire research area,accounting for more than 43 % of the area,with the largest plaque index,the largest aggregation index,and the smallest fragmentation index.It shows that the connectivity and integrity of forest landscape are stable in the change of landscape pattern.(3)From 2005 to 2016,the ratio of the area of the research area to the three functional landscape types(ecological protection,production economy and life service landscape)in2005 was 1:0.3248: 0.0463,In 2016,the area of the three functional landscapes(ecological protection,production economy,and life service landscapes)was 1:0.3515:0.0569,respectively.The area of the three functional landscapes that showed changes in ecological protection was slightly reduced.The area of the production economy and life service landscape has slightly increased,indicating that the frequency of human activities has increased and the impact on the landscape has increased.From the perspective of landscape ecology,this paper analyzes the changing trend of landscape pattern,which can provide a theoretical basis for optimizing landscape pattern in the future,and realize the sustainable development of regional ecological security and human production and consumption.It is also very important for the subsequent development of regional ecological environment construction.