城市公共绿地常见木本植物组成对鸟类群落的影响

The composition of common woody plant species and their influence on bird communities in urban green areas

快速城市化背景下,城市公共绿地已经成为重要的鸟类栖息地,其中的木本植物群落构成对鸟类群落结构有显著影响,研究木本植物配置与鸟类多样性的关系对提升城市公共绿地作为鸟类栖息地的生态服务功能有重要的理论和应用价值。我们于2009–2010年间在上海市滨江森林公园就木本植物和鸟类群落的相互关系展开研究。样线法结合样点调查共记录到鸟类10目25科64种5,368只(次),鸟类多度全年变化显著,峰值分别出现在4月和11月。丰富度全年也呈现双峰型变化,峰值出现在4月和12月。全年鸟类多样性(Simpson指数)差异显著,10月最高,8月最低。样方调查共记录到77种木本植物,其中有14种(乔木9种、灌木5种)出现率超过5个样方,定义为常见种,其果期主要集中在9月到翌年2月,其上常见林业致病害虫的发生盛期集中在5–11月。主成分分析显示,常见木本植物上观察到的鸟类可划分为8个鸟类集团,Spearman秩相关检验显示秋冬季常见木本植物果期与植食性、肉食性、食虫性、杂食性等多个鸟类集团的多度均呈显著正相关。说明在秋冬季鸟类迁徙高峰期不同鸟类集团均能获得丰富的食物资源。就常见木本植物对鸟类群落的重要值进行排序,结果显示,大叶杨(Populus lasiocarpa)、枫杨(Pterocarya stenoptera)、香樟(Cinnamomum camphora)等乔木对鸟类重要值较高,而灌木层对鸟类的重要性整体偏低,说明滨江森林公园的灌木层作为鸟类栖息地的功能建设尚需加强。根据以上研究结果,我们提出了提高上海城市公园鸟类多样性的植被配置建议。

Urban green areas are important habitats for birds in rapidly urbanized areas. The composition of woody plant species has a significant influence on the structure of bird communities in urban green areas. Therefore, to enhance the function of public green areas as wild bird habitats, we studied how woody plants influenced the composition of the bird community in Binjiang Forest Park, a typical urban green area in Shanghai city. A total of 5,368 individual birds belonging to 64 species from 25 families and l0 orders were recorded during line transect and point-count surveys conducted between 2009 and 2010. Data on bird abun- dance showed significant differences among months, with the two highest abundances recorded in April and November. A plot of the data on bird species richness against time （months） showed a curve with two peaks, with the highest abundance recorded in April and December. The values of the Simpson index showed sig-nificant variation in bird diversity over the year, with the highest value recorded in October and the lowest in August. With square-plot （400 m2） sampling analysis, a total of 77 woody plant species in the park was iden- tified. Only 14 of these species were recorded in at least five plots （nine trees and five shrubs）. These species were considered common woody species. The fruiting seasons of 12 of these species occurred during periods between September and the following February. The principal outbreaks of insects with significance to for- estry occurred from May to November. A principal component analysis was used to group all birds observed on the 14 woody plant species into 8 guilds according to their diets, foraging behaviors, and distributions in various vegetation layers. A Spearman correlation analysis indicated that the autumn-winter fruiting season was significantly positively correlated with 5 bird guilds, including vegetarians, omnivores, raptors, and in- sectivores. The abundant food supply coincided with the highest bird abundance and richness in autumn and winter. An analysis of the importance of each common woody plant species for the bird community was also performed based on the evaluation of the relative richness, relative abundance, and relative number of bird guilds. The results showed that during autumn and winter, fruiting plants provided rich food resources for terrestrial migratory birds; trees such as Populus lasiocarpa, Pterocarya stenoptera, and Cinnamomum cam- phora had a greater importance than shrubs. The relatively lower importance of the common shrub species to birds implies that the shrub community of the park needs to be reviewed. Comments and recommendations are provided based on our research results.