Wuhan Bird Habitat Network Construction

Habitat fragmentation,deterioration and loss are a warning of increased risk of species extinction.As one of the best candidates for monitoring global environmental changes,the construction of habitat networks for birds has become an important tool for urban biodiversity conservation and sustainable urban development.Currently,the construction of bird habitat networks mainly focuses on macroscopic patterns at intercontinental,regional and national scales,but lacks quantitative studies of different environmental influences at the urban scale,as well as in-depth studies of the ecological processes of bird migration.In addition,it is difficult to study the habitat preferences,behavioural motivations and pathway evolution patterns of birds in response to this process.Therefore,this study focuses on the ’object urban environment’ and ’subject biological behaviour’perspectives in order to explore the construction of a bird habitat network that synergises environmental suitability and behavioural autonomy,using Wuhan as an example.The morphological layout of the bird habitat network constructed based on environmental adaptations showed figurative results: 1)The overall habitat quality in Wuhan was less than 0.8,and the quality of the habitats was forestland > grassland > waters(wetlands)> farmland > construction in descending order.The degree of habitat degradation in descending order was farmland > forestland > grassland > waters(wetlands)>construction,and the degradation of forestland and cropland caused by urban expansion was not optimistic.High-quality forest patches in Wuhan were scattered and mainly concentrated in Sushan Temple National Forest Park in Huangpi District in the north,with a small amount distributed in the East Lake Scenic Area in the central city.2)The 849 core area patches initially extracted by the morphological pattern,combined with the 127 patches finally established by the In VEST model,could be regarded as an effective complement to the source selection.This could make up for the inadequacy of the MSPA model to use a single core area as the basis for quantifying the "source".3)The 14,769 potential migration corridors for birds constructed based on the LCP model were classified into three classes according to their length.Among them,corridors with an average length of about 12-25 km showed a "U" shaped distribution,and one followed the distribution along the Yangtze River.Habitat networks constructed based on the autonomy of bird behavior are usually sets of solutions with certain properties rather than unique deterministic solutions,and generally present a complex structure with a specific flow pattern.By understanding six common bird behaviors,setting individual movement rules,and building a flock movement model,the expression of bird path selection has shifted from the previous "decision maker selection" to "individual autonomous selection".The main manifestations are as follows:1)When the restricted maximum acceleration of "individual birds" > 0.1,the individual dispersal gradually shifted from a homogeneous and chaotic non-embodied distribution form to an abstract "U" with a "north-center-south" direction.2)When the individual’s visual field search range was maximized,the individual relied on its own autonomous behavior and further automatically migrated to the most suitable habitat patches around to breed in a prepared state.Habitat patches with high quality,large size,and multiple accommodating spatial characteristics had become the preferred source sites for birds,but there were fewer paths formed by round-trip migration into and out of the patches.The trails were particularly evident in the northern Xinzhou area.3)When the carrying capacity of individual patches was insufficient for "small groups",some "individual birds" would be forced to migrate to adjacent patches of low quality habitat or distant patches of high quality.The "density-constrained dispersal" directly caused by the spatial aggregation of individuals over time would eventually reach the "ideal free distribution" state.Thus,the network connectivity between the central city and the southern districts of Hannan and Jiangxia turned out to be high.The results of the construction of a bird habitat network with environmental suitability and behavioral autonomy showed that: 1)The hierarchical construction of the Wuhan network took into account environmental suitability and behavioral autonomy,requiring not only priority protection of 6 core sources and 12 core corridors,but also 4 additional important sources and 10 important corridors with outstanding conservation potential.More specific protection was needed for 2 key areas and 3 key points.2)The adjustment of the layout and structural optimization of the bird habitat network could not be separated from the regulation of the network density,the setting of the buffer range,the improvement of habitat quality and the prevention and control of habitat degradation.Wuhan’s bird habitat network needed to give full play to the role of urban ecological corridors in organizing and linking various development nodes in order to strengthen the connection between the south and north axes together with the central city.Meanwhile,the source buffer range should be appropriately adjusted according to the population’s resistance to disturbance,so as to form a continuous habitat space with high stability and strong carrying capacity.Especially around the Yangtze River and Hanshui,where the length and width were more influential,more waterfront forests,isolated island patches or floating islands on water need to be set up.Buffer strips with species habitat-bearing functions also needed to be set up alongside important traffic arteries.At the same time,to build and maintain a complete continuous and stable urban bird habitat network,an "arbor-shrub-herb-grass" complex structure should be adopted to optimize the existing planting communities according to the different zoning units in the central and distant urban areas respectively.3)It was suggested that a coordinated control strategy for bird habitat networks under conservation objectives should be proposed from three aspects: policy formulation and departmental coordination,equipment introduction and mechanical maintenance,and public participation and interactive teaching,with a view to providing references for urban bird habitat network construction and biodiversity conservation in Wuhan and similar cities.