Nestedness is an important part of the theoretical framework of island biogeography and community ecology.However,most previous studies focused on taxonomic dimension and overlooked functional and phylogenetic nestedn...Nestedness is an important part of the theoretical framework of island biogeography and community ecology.However,most previous studies focused on taxonomic dimension and overlooked functional and phylogenetic nestedness.Here,we simultaneously investigated taxonomic,functional,and phylogenetic nestedness of terrestrial mammals on 39 land-bridge islands in the Zhoushan Archipelago,China.As mammals’response to the environment may depend on their body size,we performed analyses for three mammal assemblages separately:overall species,large and medium-sized species,and small species.The taxonomic nestedness was quantified by organizing the species incidence matrix,while the functional and phylogenetic nestedness were estimated by combining the similarity of their ecological traits and phylogeny.Island characteristics(island area,three isolation indices,land use intensity,and habitat diversity)and species traits(body size,litter size,habitat specificity,geographic range size,and minimum area requirement)were used as predictors of nestedness.Overall and small species were significantly nested in 3 facets of nestedness,and results supported the selective extinction,selective colonization,and habitat nestedness hypotheses.Large and medium-sized species were functionally and phylogenetically nested when matrices were ordered by increasing distance to mainland,supporting the selective colonization hypothesis.Overall,differences in nestedness and its underlying mechanisms were detected not only in 3 facets of nestedness but also in the 3 mammal assemblages.Therefore,frameworks that incorporate taxonomic,phylogenetic,and functional nestedness can contribute to a more comprehensive understanding of nestedness processes.Additionally,it also improves our ability to understand the divergent responses of mammal assemblages to the insular environment.展开更多
Nestedness is one of the important patterns in island biogeography,community ecology and conservation biology.However,most previous nestedness studies focus on the taxonomic dimension while neglecting the functional a...Nestedness is one of the important patterns in island biogeography,community ecology and conservation biology.However,most previous nestedness studies focus on the taxonomic dimension while neglecting the functional and phylogenetic processes in generating nestedness.Moreover,few studies have examined the seasonal change of the nestedness and underlying processes.Here,we examined the seasonal nestedness of bird assemblages in taxonomic,functional,and phylogenetic dimensions,and determined the underlying processes of nestedness patterns in the Zhoushan Archipelago,China.We surveyed the occurrence, abundance,and habitats of birds on 40 islands.We calculated taxonomic,functional,and phylogenetic nestedness using WNODF and treeNODF.We determined the processes underlying nestedness by relating nestedness ranks to island characteristics and species traits.The WNODF analyses showed that bird assemblages in winter and summer were both significantly nested.The habitat-by-site matrix was also significantly nested.The nestedness of bird assemblages was significantly correlated with island area,habitat diversity,habitat specificity,minimum area requirement,habitat specificity and hand-wing index(HWI) of birds in both seasons.While the distance to the nearest mainland(DTM) exerted the influence on nestedness in summer,the distance to the nearest larger island(DTNL)affected nestedness only in winter.However,the nestedness of bird assemblages was not caused by passive sampling or human disturbance.The results of treeNODF analyses illustrated that bird assemblages were functionally and phylogenetically nested in summer and winter,but the exact mechanisms were somewhat different in these two seasons.Overall,our results supported the habitat nestedness hypothesis,selective extinction hypothesis,and selective colonization hypothesis in both seasons.From a conservation viewpoint,we should protect islands with large area and diverse habitats,islands close to the mainland,and species with large area requirement and high habitat specificity to prevent local extinction.展开更多
城市化对原本处于自然的空间带来了巨大的变化,鸟类是受其影响的动物类群之一。基于此,为了探究西藏自治区林芝市和拉萨市两个高海拔城市中的城市公园鸟类群落是否呈现嵌套分布格局并分析其潜在影响因素,从中国观鸟记录中心(http://www....城市化对原本处于自然的空间带来了巨大的变化,鸟类是受其影响的动物类群之一。基于此,为了探究西藏自治区林芝市和拉萨市两个高海拔城市中的城市公园鸟类群落是否呈现嵌套分布格局并分析其潜在影响因素,从中国观鸟记录中心(http://www.birdreport.cn)收集了2021至2023年间49位观鸟者在林芝市和拉萨市各14个城市公园上传的120份观鸟报告数据。采用NODF(nestedness based on overlap and decreasing fill)分别计算了林芝市和拉萨市城市公园的所有鸟类、林鸟和水鸟群落的物种维度的嵌套分布格局。同时,使用Spearman偏相关分析了嵌套序列与生境变量(如公园面积和隔离度)和物种生态学特征(如食性)之间的关系。然后,使用treeNODF度量方式计算了功能维度(traitNODF)和谱系维度(phyloNODF)的嵌套分布格局,使用函数“treeNodfTest”及零模型“permRows”检验不同生境变量对各类群鸟类群落的功能和谱系嵌套分布格局的影响。分析结果显示,除水鸟群落外,林芝市与拉萨市的所有鸟类和林鸟群落均检测出显著的物种、功能或谱系维度嵌套分布格局。林芝市全部鸟类和林鸟群落的物种嵌套与选择性灭绝相关的鸟类食性特征显著相关,鸟类生境也是显著嵌套的,而全部鸟类群落的功能和谱系嵌套主要受隔离度影响;拉萨市全部鸟类和林鸟群落的功能和谱系嵌套主要受面积影响。综上所述,为了更好地保护高海拔城市中的鸟类多样性,应因地制宜地制定保护策略:在林芝市,应优先保护食肉性鸟类和隔离度较小的公园;在拉萨市,则应优先保护面积较大的公园。基于此,建议在新建城市公园时,除了增加生境的种类数量外,还应综合考虑不同鸟类的生境需求,以促进鸟类多样性保护。展开更多
基金supported by the National Natural Science Foundation of China(32271734 and 31971545).
文摘Nestedness is an important part of the theoretical framework of island biogeography and community ecology.However,most previous studies focused on taxonomic dimension and overlooked functional and phylogenetic nestedness.Here,we simultaneously investigated taxonomic,functional,and phylogenetic nestedness of terrestrial mammals on 39 land-bridge islands in the Zhoushan Archipelago,China.As mammals’response to the environment may depend on their body size,we performed analyses for three mammal assemblages separately:overall species,large and medium-sized species,and small species.The taxonomic nestedness was quantified by organizing the species incidence matrix,while the functional and phylogenetic nestedness were estimated by combining the similarity of their ecological traits and phylogeny.Island characteristics(island area,three isolation indices,land use intensity,and habitat diversity)and species traits(body size,litter size,habitat specificity,geographic range size,and minimum area requirement)were used as predictors of nestedness.Overall and small species were significantly nested in 3 facets of nestedness,and results supported the selective extinction,selective colonization,and habitat nestedness hypotheses.Large and medium-sized species were functionally and phylogenetically nested when matrices were ordered by increasing distance to mainland,supporting the selective colonization hypothesis.Overall,differences in nestedness and its underlying mechanisms were detected not only in 3 facets of nestedness but also in the 3 mammal assemblages.Therefore,frameworks that incorporate taxonomic,phylogenetic,and functional nestedness can contribute to a more comprehensive understanding of nestedness processes.Additionally,it also improves our ability to understand the divergent responses of mammal assemblages to the insular environment.
基金supported by the National Natural Science Foundation of China (32271734)。
文摘Nestedness is one of the important patterns in island biogeography,community ecology and conservation biology.However,most previous nestedness studies focus on the taxonomic dimension while neglecting the functional and phylogenetic processes in generating nestedness.Moreover,few studies have examined the seasonal change of the nestedness and underlying processes.Here,we examined the seasonal nestedness of bird assemblages in taxonomic,functional,and phylogenetic dimensions,and determined the underlying processes of nestedness patterns in the Zhoushan Archipelago,China.We surveyed the occurrence, abundance,and habitats of birds on 40 islands.We calculated taxonomic,functional,and phylogenetic nestedness using WNODF and treeNODF.We determined the processes underlying nestedness by relating nestedness ranks to island characteristics and species traits.The WNODF analyses showed that bird assemblages in winter and summer were both significantly nested.The habitat-by-site matrix was also significantly nested.The nestedness of bird assemblages was significantly correlated with island area,habitat diversity,habitat specificity,minimum area requirement,habitat specificity and hand-wing index(HWI) of birds in both seasons.While the distance to the nearest mainland(DTM) exerted the influence on nestedness in summer,the distance to the nearest larger island(DTNL)affected nestedness only in winter.However,the nestedness of bird assemblages was not caused by passive sampling or human disturbance.The results of treeNODF analyses illustrated that bird assemblages were functionally and phylogenetically nested in summer and winter,but the exact mechanisms were somewhat different in these two seasons.Overall,our results supported the habitat nestedness hypothesis,selective extinction hypothesis,and selective colonization hypothesis in both seasons.From a conservation viewpoint,we should protect islands with large area and diverse habitats,islands close to the mainland,and species with large area requirement and high habitat specificity to prevent local extinction.
文摘城市化对原本处于自然的空间带来了巨大的变化,鸟类是受其影响的动物类群之一。基于此,为了探究西藏自治区林芝市和拉萨市两个高海拔城市中的城市公园鸟类群落是否呈现嵌套分布格局并分析其潜在影响因素,从中国观鸟记录中心(http://www.birdreport.cn)收集了2021至2023年间49位观鸟者在林芝市和拉萨市各14个城市公园上传的120份观鸟报告数据。采用NODF(nestedness based on overlap and decreasing fill)分别计算了林芝市和拉萨市城市公园的所有鸟类、林鸟和水鸟群落的物种维度的嵌套分布格局。同时,使用Spearman偏相关分析了嵌套序列与生境变量(如公园面积和隔离度)和物种生态学特征(如食性)之间的关系。然后,使用treeNODF度量方式计算了功能维度(traitNODF)和谱系维度(phyloNODF)的嵌套分布格局,使用函数“treeNodfTest”及零模型“permRows”检验不同生境变量对各类群鸟类群落的功能和谱系嵌套分布格局的影响。分析结果显示,除水鸟群落外,林芝市与拉萨市的所有鸟类和林鸟群落均检测出显著的物种、功能或谱系维度嵌套分布格局。林芝市全部鸟类和林鸟群落的物种嵌套与选择性灭绝相关的鸟类食性特征显著相关,鸟类生境也是显著嵌套的,而全部鸟类群落的功能和谱系嵌套主要受隔离度影响;拉萨市全部鸟类和林鸟群落的功能和谱系嵌套主要受面积影响。综上所述,为了更好地保护高海拔城市中的鸟类多样性,应因地制宜地制定保护策略:在林芝市,应优先保护食肉性鸟类和隔离度较小的公园;在拉萨市,则应优先保护面积较大的公园。基于此,建议在新建城市公园时,除了增加生境的种类数量外,还应综合考虑不同鸟类的生境需求,以促进鸟类多样性保护。
