Study On The Ecological Security Pattern Of Chengdu Main Districts

For a long time,urban sprawl has brought about a series of urban ecological security problems,which has a serious impact on regional ecological sustainable development.With the frequent human activities sharpen the contradiction between economic development and ecological protection,how to reduce and deal with bad effects caused by rapid urbanization has become an urgent problem.The important consensus of urbanization environment is to optimize regional ecological structure,construct ecological security pattern,as well as protect and restore the essential regional ecological process,which is also a important part of landscape planning researches on regional and urban scales.At present,the concept of ecological security patterns simply stay at the conceptual stage,and how to practice the space planning measures becomes a major problem.Chengdu,the capital city of Sichuan province,plays an important role in chengdu-chongqing economic circle.In recent years,with the acceleration of urban development and the increasing contradiction between human and land,ecological environment deterioration is also increasing,therefore,the researches on the landscape ecological security patterns of theories and methods have important practical significance.Under this background,this paper takes Chengdu city as an example,starting from the landscape pattern optimization,using the theory of landscape ecology and remote sensing science as a guide.According to the clue of "dynamic patterns-ecological response-ecological security construction",this thesis simplify the space of the landscape pattern optimization model based on PSO algorithm principle.With the aid of remote sensing satellite images and relevant analysis methods,it studied in downtown Chengdu,2000-2015,changes of landscape structure and its driving mechanism,aiming to provide theoretical and technical support for the construction of urban ecological security pattern with rational land expansion,sustainable land use and sound economic development.The main conclusions are as follows:(1)The biggest change in land use in Chengdu's main urban areas is urban land and arable land,especially arable land,which has been greatly decreased in a certain number of years.However,the patch density of the green space landscape increases which owns greater area than before,indicating that the landscape fragmentation degree is more serious,due to the outside interference.However,the patch density of the road landscape is relatively low,and its area is significantly increased,indicating that the road landscape is increasing in the city.(2)"Landscape ecological type + gradient + population density + per capita GDP" is the factor that effectively drives the potential of landscape change.The whole,the landscape pattern changes are greatly influenced by time and human activity factors,but because all kinds of landscape types shifted within the study area,and to a certain fixed number of years,area of some landscape types has reached to a certain level,therefore,before the target year,most of the landscape will maintain its existing established pattern,and its internal will complete the pros and cons of a certain amount of supplies.However,attention should be paid to the prevention of excessive and rapid reduction of farmland and woodland area.(3)The landscape pattern optimization model based on PSO landscape pattern optimization can better simulate and optimize the landscape ecological pattern.Under the model of overall situation of landscape pattern optimization scheme,the outcome can combine economic and ecological benefit of,and it's is an optimal choice for the study area.