Studies On Bird Diversity Based On The Occupation Model Under The Background Of Rapid Urbanization

In the context of rapid urbanization,urban forest patches were typically fragmented ecosystems influenced by urban climate.Exploring the seasonal dynamics and distribution patterns of bird diversity in Wuhan forests can help understand the distribution patterns of urban species diversity and its mechanism.It can also provide the scientific basis for the prediction of biodiversity distribution patterns in response to the environment,the assessment of urban ecosystem health and the construction and maintenance of urban landscape patterns.During 2020 to 2022,bird diversity surveys were carried out in 30 forest patches in Wuhan city using the sample lane and infrared camera trapping.I wanted to investigate seasonal dynamics and distribution patterns of birds in Wuhan city.To avoid the influence of incomplete detection,the multi-species occupancy model was used to study the distribution patterns of bird diversity.The results showed that:(1)There are 419 species of birds,belonging to 21 orders and 75 families,in the forest patches in Wuhan city,of which a total of 34,760 individuals,belonging to 150 species in16 orders and 44 families,were recorded by field survey,while the other species were recorded from the references.The Shannon-Wiener diversity index of Wuhan birds was1.501,and the Pielou evenness index was 0.689,dominated by birds of the Passeriformes.The type of residence was dominated by resident species.The fauna type was dominated by oriental species,with one species of wild birds under the national Class I key protection and 15 species of wild birds under the national Class II key protection.The degree of seasonal variation of forest bird communities in Wuhan was high,and the bird species diversity indices were all highest in spring,followed by summer and winter,and lowest in autumn.The diversity of bird communities in remote suburban forest patches were significantly higher than those in urban areas in spring,summer and autumn,and higher than those in suburban forest patches only in summer and winter,and the abundance did not vary significantly between suburban and urban gradients.(2)The species richness and functional diversity of bird communities showed a trend of increasing and then decreasing with the distance to center increased,and the phylogenetic diversity increased with the distance to center increased.The phylogenetic diversity and functional diversity showed a quadratic curve of increasing and then decreasing along the urban-suburb-rural gradient;the standardized mean phylogenetic distance and mean functional distance both increased along the gradient.Bird community diversity were significantly and positively correlated with circumference,area,mean annual temperature,minimum temperature in the coldest month,annual precipitation.The mean daily solar radiation,the standardized mean spectral distance and functional distance of species were significantly and positively correlated with the distance to center and mean daily solar radiation.(3)With the increase of circumference and daily average solar radiation,the detection rate of species in the community decreases.Meanwhile,with the increase of annual precipitation and solar radiation,the species occupancy rate in the community increased.The community’s occupancy rate and detection rate in the non-breeding season were significantly lower than those in the breeding season.In addition,the observed values of the bird diversity in Wuhan were underestimated.In detail,the functional diversity index,the phylogenetical diversity index and standardized effect size of mean phylogenetic distance and functional distance have a cubic relationship with the distance to center,while occupancy model predictions of functional and phylogenetic diversity indices fitted to distances to center were quadratic.In summary,forest bird resources in Wuhan were abundant and fluctuated greatly between seasons.The distribution pattern of bird diversity in Wuhan forests increased and then decreased with increasing distance to center,which means the diversity of birds in forest patches in medium urbanized areas reached a peak,the distribution pattern of structural index increased with increasing distance to center.These outcomes indicate that urbanization has a negative impact on bird diversity,and some birds may have adapted to urbanization.Incomplete detection leads to bias in the distribution patterns of bird community diversity and the community structure,consequently the variation of occupancy rate and detection rate along the environmental gradient should be considered in the data analysis.Wuhan should strengthen the survey and monitoring of bird resources in the rural,especially the national key protected birds,and develope appropriate protection strategies according to patch conditions.It suggests that degraded vegetation should be restored in urban and suburb forest patches to improve habitat quality,and protection should be enhanced in rural forest patches to reduce human interference.