Li Binqiang, Bibi Nehafta, Ma Shanjun, Chen Wenxuan, Yang Miaodan, Xiang Na, Cui Qingjiang, Tan Lifeng
College of Forestry, Southwest Forestry University, Kunming, China College of Forestry, Southwest Forestry University Kunming China.
Planing and Design Institute, Yunnan Forestry Technological College, Kunming, China Planing and Design Institute, Yunnan Forestry Technological College Kunming China.
Biodivers Data J. 2025 May 21;13:e154385. doi: 10.3897/BDJ.13.e154385. eCollection 2025.
Urbanisation significantly impacts the composition and distribution of species through habitat loss and fragmentation. Nestedness is a significant pattern often observed in species assemblages on islands or within fragmented systems. However, numerous studies on nestedness have focused on species richness and composition, neglecting the role of species traits in generating and explaining nestedness. To determine whether functional nestedness follows the same pattern as taxonomic nestedness. In this study, we examined the nestedness patterns of bird assemblages (all birds, passerines, insectivorous, omnivorous and resident birds) across 17 urban parks in Liuzhou of Guangxi Province, China, focusing on taxonomic and functional nestedness. From April 2021 to February 2022, we conducted line transect surveys of bird communities, with three surveys during the breeding season and three surveys during the non-breeding season. In total, we documented 95 bird species. Taxonomic nestedness was assessed using NODF (a nestedness metric, based on overlap and decreasing fill) and WNODF (weighted nestedness metric, based on overlap and decreasing fill) metrics, while functional nestedness was evaluated using treeNODF. Our results showed that none of the birds, passerines, insectivorous, omnivorous and resident birds in Liuzhou urban parks exhibited significant nestedness patterns. However, the nested pattern strongly depended on the choice of the null model. In contrast, as the park area gradually decreases, we observed significant functional nestedness, implying that the trait loss in parks with decreasing area follows an ordered pattern, where smaller parks represent nested subsets of functional traits found in larger parks. From the perspective of species conservation, we recommend prioritizing the protection of larger urban parks to support species with larger habitat requirements. All in all, our findings highlight the importance of considering both taxonomic and functional nestedness in urban biodiversity conservation.
城市化通过栖息地丧失和破碎化对物种的组成和分布产生重大影响。嵌套性是在岛屿或破碎化系统中的物种组合中经常观察到的一种重要模式。然而，许多关于嵌套性的研究都集中在物种丰富度和组成上，而忽略了物种特征在产生和解释嵌套性方面的作用。为了确定功能嵌套性是否与分类嵌套性遵循相同的模式。在本研究中，我们调查了中国广西柳州17个城市公园中鸟类群落（所有鸟类、雀形目鸟类、食虫鸟类、杂食鸟类和留鸟）的嵌套性模式，重点关注分类嵌套性和功能嵌套性。2021年4月至2022年2月，我们对鸟类群落进行了样线调查，繁殖季节进行了三次调查，非繁殖季节进行了三次调查。我们总共记录了95种鸟类。使用NODF（一种基于重叠和递减填充的嵌套性指标）和WNODF（加权嵌套性指标，基于重叠和递减填充）指标评估分类嵌套性，而使用treeNODF评估功能嵌套性。我们的结果表明，柳州城市公园中的所有鸟类、雀形目鸟类、食虫鸟类、杂食鸟类和留鸟均未表现出显著的嵌套性模式。然而，嵌套模式强烈依赖于零模型的选择。相比之下，随着公园面积逐渐减小，我们观察到显著的功能嵌套性，这意味着面积减小的公园中的特征丧失遵循一种有序模式，其中较小的公园代表较大公园中发现的功能特征的嵌套子集。从物种保护的角度来看，我们建议优先保护较大的城市公园，以支持对栖息地有较大需求的物种。总而言之，我们的研究结果凸显了在城市生物多样性保护中考虑分类嵌套性和功能嵌套性的重要性。
