生物多样性 ›› 2021, Vol. 29 ›› Issue (5): 661-667.DOI: 10.17520/biods.2020336

• 研究简报 • 上一篇    下一篇

贵州花溪大学城破碎化林地鸟类多样性与嵌套分布格局

郑进凤1, 唐蓉1, 贺霜1, 陈月红1, 伍素1, 张凯1, 徐雨1,*(), 邹晓2   

  1. 1.贵州师范大学生命科学学院, 贵阳 550025
    2.贵州大学生命科学学院, 贵阳 550025
  • 收稿日期:2020-08-20 接受日期:2020-12-27 出版日期:2021-05-20 发布日期:2021-02-16
  • 通讯作者: 徐雨
  • 作者简介:* E-mail: xuyu608@gznu.edu.cn
  • 基金资助:
    国家自然科学基金委员会-贵州省人民政府喀斯特科学研究中心项目(U1812401)

Bird diversity and nestedness on fragmented woodlots in Huaxi University Town, Guizhou Province

Jinfeng Zheng1, Rong Tang1, Shuang He1, Yuehong Chen1, Su Wu1, Kai Zhang1, Yu Xu1,*(), Xiao Zou2   

  1. 1 School of Life Sciences, Guizhou Normal University, Guiyang 550025
    2 School of Life Sciences, Guizhou University, Guiyang 550025
  • Received:2020-08-20 Accepted:2020-12-27 Online:2021-05-20 Published:2021-02-16
  • Contact: Yu Xu

摘要:

为揭示城镇化进程中生境破碎化对鸟类多样性及分布格局的影响, 本研究于2017-2019年每年的4-8月使用样线法对贵州花溪大学城26块破碎化林地(面积介于0.3-290.4 ha)中的鸟类群落进行了10次调查。共记录到鸟类78种, 隶属于11目37科。其中, 东洋界物种数占56.4%, 古北界物种数占32.1%, 广布种占11.5%; 有中国特有种1种。剔除高空飞行、非森林鸟类及偶然出现物种后, 不同斑块中的鸟类物种数介于12-55之间, 平均每个斑块有23.2 ± 10.5种。线性回归分析显示, 鸟类物种丰富度与林地斑块的面积有显著相关性, 斑块面积越小, 鸟类物种丰富度越低; 斑块隔离度对物种丰富度没有显著影响。基于物种多度分布矩阵的WNODF (weighted nestedness metric based on overlap and decreasing fill)嵌套分析显示, 不同斑块中鸟类群落呈现出反嵌套结构。小斑块中鸟类物种丰富度较低可能与植物丰富度较低、食物资源稀缺和繁育条件不足有关, 但短距离的隔离对鸟类迁入或扩散影响有限。环境过滤效应、种间竞争或优先效应可能导致不同斑块间存在较大的物种组成差异, 从而导致反嵌套格局。因此, 本研究建议在城市规划建设中应注重维持栖息地的完整性, 对不同面积大小的破碎化斑块都应加以保护。

关键词: 斑块, 面积, 隔离度, 嵌套格局, 物种丰富度, 生物多样性, 城市化

Abstract

Aim: To examine the impact of habitat fragmentation stemming from urbanization on bird diversity and distribution patterns.
Methods: We surveyed bird assemblages on 26 fragmented woodlots with areas of 0.3-290.4 ha in Huaxi University Town, Guizhou Province from April to August between 2017 and 2019. We surveyed birds by establishing line transects in each woodlot, with transect length roughly proportional to the woodlot area. We surveyed each line transect 10 times over the course of the study period, and recorded birds detected within 50 m of either side of the line transects.
Results: In total, we recorded 78 bird species belonging to 11 orders and 37 families. Species of Oriental origin, Palaearctic origin, and widespread species accounted for 56.4%, 32.1%, and 11.5% of observations, respectively. We observed one species endemic to China. After excluding birds detected as fly-overs (e.g., swallows and swifts), non-forest dwelling birds (e.g., waterbirds), and birds that were only recorded once in the survey, we found that the number of bird species in different woodlots ranged from 12 to 55 species, with an average of 23.2 ± 10.5 species per woodlot. Linear regression analysis showed that bird species richness was significantly positively correlated with woodlot area, with larger woodlots having higher bird richness. A metric of isolation, measured as the distance to the nearest neighboring woodlot, had no significant effect on bird species richness. The analysis of nestedness, based on the metric WNODF (weighted nestedness metric based on overlap and decreasing fill), conducted on the species-by-site abundance matrix, revealed that the observed WNODF for sites of birds was significantly lower than expected from the null model, indicating that bird assemblages were anti-nested among the woodlots.
Conclusion: Our results suggest that plant richness, food resources and breeding conditions in small woodlots may be diminished compared to larger woodlots, making it difficult for some bird species to meet their survival needs. However, the relatively short distance between woodlots in our study sites combined with the stronger dispersal ability of birds may mask the biological importance of isolation. The anti-nested structure of bird communities may be the result of larger differences in species composition between woodlots being driven by environmental filtering, interspecific competition, or priority effects, but further research is needed to determine the likely causal mechanism of anti-nestedness. Nevertheless, given that rapid urban expansion has caused substantial habitat fragmentation in recent decades in our study area, we recommend that habitat integrity should be prioritized and maintained in urban planning when possible, and that fragmented woodlots of different sizes be protected.

Key words: patch, area, isolation, nestedness, species richness, biodiversity, urbanization