郑州城市公园鸟类群落嵌套分布格局及其影响因素

为了探究郑州城市公园鸟类群落是否符合嵌套分布格局及其影响因素,本研究从中国观鸟记录中心收集了2019–2022年每年3–7月河南省郑州市15个城市公园的鸟类记录数据。使用WNODF(weighted nestedness metric based on overlap and decreasing fill)分别计算郑州城市公园全部鸟类、林鸟和水鸟群落的嵌套分布格局,采用Spearman偏相关检验分析了公园嵌套序列与公园特征参数(公园面积、隔离度、生境类型数量和建筑指数)的关系,以及物种嵌套序列与物种生态学特征(体长、地理分布范围、窝卵数和最小面积需求)的关系。WNODF分析结果显示,郑州城市公园全部鸟类、林鸟和水鸟群落均是显著嵌套的。Spearman偏相关分析结果显示,公园面积和最小面积需求与鸟类群落嵌套程度显著相关,生境地点矩阵分析结果显示为显著嵌套,建筑指数也会影响水鸟群落的嵌套分布格局,但随机放置模型结果显示城市公园鸟类不符合被动取样假说。因此,选择性灭绝与生境嵌套是郑州城市公园全部鸟类、林鸟和水鸟群落嵌套分布格局的主要驱动因素。研究结果表明,为了更好地保护郑州城市公园的鸟类多样性,应优先保护面积较大和生境类型多的公园,以及最小面积需求大的鸟类;同时由于水鸟与林鸟对城市化的反应不同,在制定保护策略时应区别对待。

Selective extinction and habitat nestedness are the main drivers of lizard nestedness in the Zhoushan Archipelago

Nested subset pattern(nestedness)is an important part of the theoretical framework of island biogeography and community ecology.However,most previous studies often used nestedness metrics or randomization algorithms that are vulnerable to type I error.In this study,we inves-tigated the nestedness of lizard assemblages on 37 islands in the Zhoushan Archipelago,China.We used the line-transect method to survey species occurrence,abundance,and habitat types of lizards on 37 islands during 2 breeding seasons in 2021 and 2022.We applied the nested metric WNODF and the conservative rc null model to control for type I error and quantify the significance of nestedness.Spearman rank cor relations were used to evaluate the role of 4 habitat variables(island area,2 isolation indices,and habitat diversity)and 4 ecological traits(body size,geographic range size,clutch size,and minimum area requirement)in generating nestedness.The results of WNODF analyses showed that lizard assemblages were significantly nested.The habitat-by-site matrix estimated by the program NODF was also significantly nested,support-ing the habitat nestedness hypothesis.The nestedness of lizard assemblages were significantly correlated with island area,habitat diversity.clutch size,and minimum area requirement.Overall,our results suggest that selective extinction and habitat nestedness were the main drivers of lizard nestedness in our system.In contrast,the nestedness of lizard assemblages was not due to passive sampling or selective colonization.To maximize the number of species preserved,our results indicate that we should protect both large islands with diverse habitats and species with largearea requirement and clutch size.

Nestedness of waterbird assemblages in the subsidence wetlands recently created by underground coal mining

Nestedness has been a research focus in fields of island biogeography and community ecology in recent decades. Although nestedness of faunal assemblages has been investigated in natural wetlands, it remains largely unknown whether and why waterbird communities in artificial wetlands follow n ested patter ns. We exami ned the existence of n ested ness and un derlyi ng drivers in waterbird comm un ities in subside nee wetlands that are recently created by large-scale un derground coal mining in the North China Plain. Twelve point-count surveys for waterbirds were undertaken approximately every 2 weeks in 55 subside nee wetla nds from September 2016 to April 2017. We used the metric WNODF to estimate nestedness of the assemblages. Partial Spearman rank correlations were performed to examine the association between the nestedness and habitat variables (wetland area, landscape connectivity, wetland age, and habitat diversity) as well as life-history traits (body size, clutch size, dispersal ratio, geographical range size, and migrant status) related to species exti notion risk and colon izati on rate. Waterbird assemblages in the subside nee wetla nds were significantly nested. After controlling for other independent variables, the magnitude of nestedness was significantly and negatively correlated with wetland area and species trait linked to extinction risk (i.e., geographical range size). Our results indicate that selective extinction may be the main driver of the nestedness of waterbird assemblages in our study system. However, the nestedness was not due to passive sampling, selective colonization, or habitat diversity. From a conservation viewpoint, both large wetlands and waterbirds with a small geographic range should be protected to maximize the preserved species richness.