Research On Evaluation And Pattern Construction Of Ecological Security In Jinzhou District Based On Landscape Analysis

Coastal towns are important strategic nodes in the building of “The Belt and The Road”.With the rapid completion of the coastal economic belt,it is urgent and necessary to construct and optimize the coastal urban landscape pattern and ecological security pattern.Based on the theory of landscape ecology,this study combines the ecological security pattern and the construction of ecological networks.By the virtue of remote sensing and geographic information system platforms,and the use of relevant mathematical models,it conducted the remote sensing images of Jinzhou District during the four periods of 2002,2005,2010,and2015.According to the national land use status classification standard(GBT20010-2007)to classify land types and select 14 landscape indices,it analyzes the spatial-temporal evolution of landscape patterns in Jinzhou District during 2002-2015;By means of the state-hazard model assessment method,it describes the evolution trajectory of the state index,hidden danger index,and the coupling index of the four periods in Jinzhou District;On the basis of the comprehensive dynamic assessment of the four periods,according to the minimum cumulative resistance model,the future ecological security pattern of Jinzhou District is constructed,and some optimization suggestions are put forward.The details are as follows:1.Analysis of spatial-temporal evolution of landscape pattern: Using the landscape-index software Fragstats to calculate the landscape index changes in 2002,2005,2010 and 2015,respectively.The results showed that the number of land use map spots in Jinzhou District increased year by year,landscape fragmentation climbed,landscape diversity increased,and spatial distribution became more uniform.Landscape patterns tend to be fragmented and agglomerated at different times.The main land types are cultivated land,construction land and other lands,which are in line with the changes in the urban landscape pattern with the increase in urban population.The area of waters,grasslands,and forests has shrunk year by year.Patch boundaries have been gradually regularized and the number of patches for ecological land has decreased.Some ecological land use patches have been disconnected from other ecological lands and landscape connectivity has been greatly reduced.2.Evaluation of integrated ecological security evolution: Based on the P-S-R model and the five major circle construction state evaluation index system and hidden danger evaluation index system,the coupling is based on the multi-objective decision-making theory and the satisfaction function,and the coupling index is calculated.The state index and hidden dangerindex are determined based on the dynamic assessment system for the level of ecological security warning.The results show that from 2002 to 2005,the comprehensive ecological security in Jinzhou District was at the level of level III warning;the integrated ecological security at the level of level IV warning from 2010 to 2015 was in a downward trend.The areas with low levels of ecological security are mainly concentrated in the western part of the Bohai Sea,southern built-up areas,parts of the central part,and parts of the northern part of the country.The results of the study and the rapid economic development have led to a rapid increase in the population and occupy a large amount of land and changed the original methods of land use and the destruction of the ecological environment,the pollution of the ecological environment,and the reduction of living space.With the unreasonable land use methods such as reclamation of the sea,coastal wetlands,tidal flats,and nature reserves have suffered various degrees of damage,affecting the overall level of ecological security.3.Construction of ecological security pattern: According to the actual situation in the study area,according to the minimum cumulative resistance model,by the use of the grid interpolation method in ArcGIS to analyze the importance of Jinzhou ecological area,extract important and above ecological area patches as “source”.Select elevation,slope,land cover,soil erosion sensitivity and soil type as ecological resistance factors,build resistance surface,perform weighted overlay analysis in ArcGIS to generate comprehensive resistance surface,and form a minimum path based on “source” distribution to minimize The path is based on the construction of ecological corridors,the organic combination of ecological patches,the use of ecological island knowledge as a "stop foot stone",the formation of ecological transition patches,reconstruction of ecological networks.And put forward optimization suggestions.