Study On The Impact Of Ecological Environment Change On Ecological Network Pattern In Yichang City Center

Rapid urbanisation and frequent human activities have resulted in huge changes in land use structure,leading to various ecological problems such as degradation of ecological functions and reduction of biodiversity in urban areas,which threaten urban ecological security.The construction of urban ecological networks can help protect urban biodiversity and maintain the stability of ecological processes,which is of great significance to the sustainable development of cities.Based on this,this paper takes the central urban area of Yichang as the research area,analyses the ecological environment evolution characteristics of the region from 1980 to 2020 using 3S technology and other methods,constructs the potential ecological networks of focal species in different periods,reveals the influence of ecological environment changes on the evolution of ecological network patterns,and proposes strategies for the construction of ecological networks in the central urban area of Yichang:(1)The characteristics of ecological environment change in the central urban area of Yichang City from 1980 to 2020 are obvious.During the period 1980-2020,the area of forested land decreased by 3.18%,the area of cultivated land decreased by 2.78%,and the area of construction land changed the most,rising by 5.1%,with a large amount of forested land shifting to construction land.Diversity Index,Landscape Shape Index and Landscape Separation Index all increased,while the Aggregation Index decreased significantly and the fragmentation of landscape patches deepened.Habitat quality as a whole showed a decreasing trend,and the proportion of different habitat quality classes and spatial distribution characteristics of each focal species varied significantly between 1980 and 2020,with the area of high quality habitat for egrets,black-spotted side-folded frogs and grass hares all decreasing,and yellow-bellied tits changing insignificantly.Habitat quality decline areas were mainly distributed in the new construction land areas of Xiling District,Wujiagang District and Intimidation District,and habitat quality enhancement areas coexisted with habitat quality decline areas,and the rate of quality decline exceeded the rate of quality enhancement.(2)Ecological changes in the central urban area of Yichang have had a significant impact on the ecological network pattern.The ecological network of the yellow-bellied tit has spread to the northeast,the ecological network of the egret has gradually reduced in distribution and clustered towards the centre,the ecological network of the black-spotted side-folded frog has also shown a reduction in distribution,and the ecological network of the grass hare is mainly distributed in the central part of the study area,with a weakening tendency of clustering.The ecological network of the grass hare is mainly distributed in the central part of the study area,and its aggregation tends to weaken.(3)The construction of ecological networks will be conducive to the conservation and restoration of biodiversity.It is recommended that ecological source sites be protected in a hierarchical manner,with ecological boundaries strictly controlled to protect the integrity of ecological source sites;that ecological corridors be constructed with consideration for the suitable migration environment for major species,and that landscape types be reasonably constructed to enhance connectivity between ecological source sites;that ecological pinch points be strengthened,ecological barrier points be repaired,and that "stepping stone" patches be cultivated to ensure the integrity and connectivity of ecological networks.To ensure the integrity and connectivity of the ecological network.In the face of the ecological problems brought about by rapid urbanisation,this study further deepens the understanding of urban ecological networks through the study of ecological changes and ecological network patterns in the central city of Yichang.The research results can be applied to the planning of urban green space systems and biodiversity conservation to mitigate the impact of human activities on the ecological environment,promote ecological balance and lead the healthy development of the human habitat.