海口和三亚两城市破碎化林地中鸟类群落多样性与嵌套分布格局

城市化是生物多样性快速丧失的主要原因之一。鸟类作为城市生态系统的重要组成部分, 其生物多样性格局和物种保护已成为城市生态学研究的热点。为揭示城市化过程中城区和郊区破碎化林地中鸟类群落的多样性差异和嵌套格局, 本研究于2021年春、夏季鸟类繁殖期采用样线法对海口和三亚市的城区、郊区共13个林地斑块中的鸟类群落进行调查。使用NODF (nestedness metric based on overlap and decreasing fill)和WNODF (weighted nestedness metric based on overlap and decreasing fill)方法进行嵌套格局分析。研究发现: (1)共记录到林鸟100种, 隶属于11目39科, 其中三亚郊区的鸟类丰富度最高, 共8目29科68种。记录到国家重点保护鸟类共18种, 其中两城市郊区的国家重点保护鸟类物种数均多于城区, 海口郊区还记录到国家I级重点保护鸟类黄胸鹀(Emberiza aureola)。(2)鸟类群落多度、物种丰富度、Pielou均匀度指数和Shannon-Wiener多样性指数在不同区域中均存在差异。海口城区的鸟类群落多度显著高于海口郊区(P < 0.05), 三亚郊区的鸟类群落物种丰富度、Pielou均匀度指数和Shannon-Wiener多样性指数均显著高于三亚城区和海口郊区(P < 0.05)。(3)嵌套分析结果表明, 海口和三亚市的城区、郊区林地鸟类群落均呈现反嵌套分布格局。线性回归分析显示, 三亚市城区和郊区的斑块面积与鸟类物种丰富度呈显著正相关, 而物种丰富度与斑块距最近大面积林地的距离之间无显著相关性。研究表明, 两城市鸟类群落多样性都表现出郊区高于城区的特点, 少数优势种(如白头鹎 Pycnonotus sinensis)占据了城市中的主要生态位。受城市化的影响, 海口郊区与城区鸟类群落有同质化的趋势。鸟类在城区和郊区斑块间的高流动性、种间竞争和斑块中资源的可利用性等因素可能导致斑块间鸟类群落的反嵌套分布格局。我们建议应加强城区和郊区鸟类的保护, 减少对林地的破坏, 提高城市鸟类多样性。     

小尺度下柠条林破碎化生境对地表甲虫多样性的影响

一般认为,景观斑块面积和破碎化对物种丰富度和分布格局有重要的影响。在宁夏中部荒漠地区,天然柠条林和人工柠条林地交错排列,形成点、片、带状等大小不等的斑块性分布,表现为典型的破碎化斑块格局生境特征。本文采用巴氏罐诱法调查了在小尺度下荒漠景观人工柠条林破碎化生境不同斑块内地表甲虫的物种多样性。结果共获得10科20属29种地表甲虫,其中拟步甲科昆虫占绝对优势,阿小鳖甲Microdera kraatzi alashanica Skopin、克小鳖甲Microdera kraatzi kraatzi(Reitter)为优势种。Rarefaction曲线显示较大面积的斑块有较多的物种多样性,但群落多样性指数各斑间块差异不显著。利用斑块面积对物种数-个体数进行回归分析表明,地表甲虫的物种多样性受斑块面积的影响,生境破碎化会导致地表甲虫多样性下降。     

广州城市绿地留鸟嵌套分布格局及其影响因素

城市景观特征对鸟类群落结构的影响是当前城市生态学值得关注的主题,对其的研究可为城市建设与鸟类保护的协同发展提供科学依据。为探讨鸟类群落组成在不同城市景观特征下的变化规律,于2017—2019年对广州市20个城市绿地斑块进行鸟类调查,分析鸟类嵌套格局及其影响因素。1）共记录鸟类18目50科139种,每个绿地斑块记录鸟类22～53种,其中留鸟最多,为75种,占53.96%。2）利用可处理物种多度信息矩阵的WNODF进行嵌套格局分析,发现绿地斑块中留鸟群落表现出显著的反嵌套结构。3）留鸟群落在绿地斑块中的分布是非随机的,被动取样假说不是该区域鸟类嵌套格局的原因,选择性灭绝、生境嵌套和人为干扰可能对该区域鸟类反嵌套格局的形成有一定作用。     

贵州花溪大学城破碎化林地中鸟类群落的小岛屿效应

小岛屿效应打破了传统的种-面积关系认知,是当前岛屿生物地理学与生境破碎化领域的研究热点之一。然而,目前的研究缺乏以人类干扰度较高的城市破碎化生境为载体来探究小岛屿效应问题。本研究以贵州花溪大学城30个面积0.25 ~ 290.40 hm2的残存自然林地为研究区,在2017至2021年的鸟类繁殖季对林地中的鸟类进行调查。共记录到鸟类98种,隶属于11目41科。剔除高空飞行、非森林鸟类及偶然出现的物种后,不同斑块中的鸟类物种数介于12至49种之间,平均每个斑块24种。在R软件中利用“sars”包构建4种关键种-面积回归模型发现,先平后升的两段式回归模型是预测种-面积关系的最佳模型。该模型显示,在面积阈值1.16 hm2之上,物种丰富度随着面积的增加逐渐增多,符合传统岛屿生物地理学提出的面积效应;但是,在面积阈值1.16 hm2之下,物种丰富度不随面积发生显著变化,表现出小岛屿效应的特征。小岛屿效应的形成可能与喀斯特特殊地貌环境、食物资源或“中转站”、“垫脚石”等生态功能相关,其具体发生机制尚有待进一步研究。根据本研究结果,建议在城市规划建设时尽可能保护自然林地并设计绿色过渡带,在优先保护大林地斑块的同时不应忽视对具有重要生态价值的小林地斑块的保护。     

破碎化次生林斑块面积及栖息地质量对繁殖鸟类群落结构的影响

于1998～2000年夏季。运用GPS定位系统确定了12块面积范围为6．5～112．8hm。的彼此隔离的森林斑块。比较了斑块面积和栖息地质量对繁殖鸟类群落结构的影响。结果表明：不同面积斑块中繁殖鸟类的群落结构有所差异。各斑块所容纳的繁殖鸟类的物种数从4种到26种不等。鸟类物种数随着斑块面积的增大而增多。不同鸟类对斑块面积的反应并不相同,耐边缘种偏爱面积较小的斑块。而非边缘种偏爱在大面积的斑块中繁殖。斑块栖息地质量也是影响鸟类群落结构的重要因素,质量好的斑块包容的鸟类物种较多。鸟类物种丰富度与斑块质量的相关性(R2=0．67)小于与斑块面积的相关性(R2=0．88)。各斑块中的鸟类群落结构在不同年份间比较相似。栖息地破碎化不但缩小了栖息地面积。同时也不同程度地降低了栖息地的质量。从而消极地影响着鸟类群落结构的稳定性和鸟类的物种多样性。     

千岛湖雀形目鸟类群落嵌套结构分析

2006年4月至2007年11月, 采用截线法对千岛湖20个岛屿上的雀形目鸟类种类组成进行调查, 检验其群落是否符合嵌套式分布的格局。此外通过野外直接记录与辨认法对岛屿上的植物种类组成进行调查, 同时通过查阅文献资料和野外调查获得鸟类体长、分布宽度和生境专属性等生活史特征参数, 以及采用GIS分析测定岛屿面积和隔离度参数, 进而分析和探讨雀形目鸟类群落嵌套格局的影响因素。结果显示, 千岛湖岛屿雀形目鸟类群落呈现显著的嵌套结构, 岛屿面积、植物物种丰富度和生境专属性对其嵌套结构具显著性的影响。千岛湖岛屿雀形目鸟类存在着选择性灭绝过程; 植物物种丰富度和鸟类生境专属性则通过影响鸟类在不同生境下的分布对鸟类群落嵌套结构产生影响。上述结果表明千岛湖岛屿雀形目鸟类群落嵌套格局同时受到栖息地和物种两方面因素的影响, 为此我们认为应更多地关注那些面积较大和植物物种丰富度较高的岛屿, 以及生境专属性较高的种类等鸟类多样性及其栖息地的保护策略。     

园林鸟类群落的岛屿性格局

岛屿群落由于受岛屿栖息地特征结构的影响而产生一系列特殊的格局。通过对杭州市园林鸟类群落的研究,分析了园林鸟类群落的物种数、组成和多度与园林岛屿性状的关系,从而确定了园林鸟类群落存在如下与园林的岛屿性状有关的格局:(1)在物种数方面,在相同的取样面积下,园林的物种数随园林面积的增大而减少;(2 )在群落组成上,园林鸟类群落呈现出不完全的嵌套格局,分布于物种数较少的园林中的物种多数也分布在物种数较多的园林中;(3)在物种多度方面,园林鸟类的总密度随面积的增大而减少,园林鸟类多度的均匀度随着面积的增大而提高。群落的岛屿性格局反映了栖息地的岛屿化对群落的影响,总称之为群落的岛屿效应。通过比较全年、繁殖季节、越冬季节和迁徙季节群落岛屿性格局的显著性,分析群落的稳定性与群落岛屿效应之间的关系,认为两者之间没有必然的联系,相对非稳定的群落也可导致显著岛屿效应     

宁夏罗山国家级自然保护区鸟类区系特征及群落结构

自2010年10月至2011年12月对宁夏罗山国家级保护区鸟类区系及群落结构进行了调查研究,共记录到鸟类15目46科98属164种,占宁夏已知鸟类总种数的48.81%。其中留鸟51种(31.10%),夏候鸟68种(41.64%),旅鸟38种(23.17%),冬候鸟7种(4.27%)。繁殖鸟119种,其中以古北界鸟类占优势,有88种,占繁殖鸟总数的73.95%;东洋界种15种,占12.61%;广布种鸟类16种,占13.45%。研究发现不同季节、不同生境中的鸟类群落特征差异较大。林地鸟类物种数和多样性指数最高,水域鸟类具有最高的G-F指数。相似性分析显示,山地荒漠草地和废弃村庄的鸟类群落,林地和浅山灌丛鸟类群落,分别具有一定的相似性。春季鸟类群落物种数、G-F指数、多样性指数和均匀度指数最高。     

湖北七姊妹山国家级自然保护区鸟类多样性及空间分布格局

为全面了解七姊妹山国家级自然保护区鸟类资源状况, 于2018年7月至2019年6月采用样线法、样点法, 对保护区鸟类种类, 生境、分布状况进行调查。结果显示: (1)保护区有鸟类251种, 隶属16目52科; 其中, 留鸟128种(51.00%)、夏候鸟80种(31.87%)、冬候鸟27种(10.76%)、旅鸟16种(6.37%)。区内以繁殖鸟类为主, 珍稀濒危鸟类种类多, 鸟类资源的保护价值高。(2)鸟类区系中, 东洋界物种141种(56.18%)、古北界物种71种(28.29%)、广布种39种(15.53%), 以东洋界占优势, 并呈现与古北界、广布种相混杂的格局。(3)各生境类型中的鸟类丰富度从高到低依次为林地＞灌丛＞河湖湿地＞草地＞村落耕地; 林地与灌丛之间的鸟类群落结构相似性最高, 林地与河湖湿地的最低。(4)保护区鸟类空间分布格局, 在垂直方向上呈单峰模式, 物种丰富度与海拔区段间存在显著的二次方程关系: y =-2.7976x2+ 22.631x + 32.75(R2=0.954, P<0.001); 在水平方向上全部鸟类丰富度呈现两端较低中间较高的分布格局。通过调查分析既丰富了七姊妹山国家级自然保护区和武陵山系的鸟类资料, 也为保护区进行保护决策提供科学依据。     

松嫩平原破碎化羊草草甸退化演替系列植物多样性的空间格局

物种多样性格局是国际生物多样性科学前沿领域热点问题.本文以松嫩平原破碎化羊草草甸退化演替系列(6种植物群落、144个斑块)为研究对象,系统地探讨了其α、β和γ多样性空间格局及其机理.结果表明:在羊草草甸退化演替系列中共发现87种植物,但没有一种能分布于所有斑块;羊草+鸡儿肠群落或羊草群落的α、β和γ多样性较高,多稀有种和特有种;碱地肤群落最低,少稀有种,无特有种;γ多样性与α多样性显著正相关,但与β多样性无相关性.各植物群落的α多样性与单个斑块面积呈显著幂函数关系,β多样性(相似性指数Sjk)仅羊草+鸡儿肠群落呈显著幂函数关系;斑块平均面积和总面积与α、γ多样性呈显著正相关,与β多样性无相关性.群落的物种丰富度越高,稀有种和特有种就越多,物种在局域斑块上灭绝的可能性越大;β多样性在物种多样性格局中的重要性与生境破碎化程度有关.     

上海闵行区园林鸟类群落嵌套结构

城市中的园林绿地呈现斑块状分布,其栖息地特征与岛屿栖息地相似。2008年11月至2009年10月,对上海市闵行区内的7块城市绿地进行调查,记录雀形目鸟类的分布情况,并运用Nestedness temperature calculator软件,检验其群落结构是否符合嵌套结构。运用Arc GIS软件分析该地区的卫星图片,收集7块样地的面积、绿地盖度、水源距离和人为干扰程度等数据,结合实地调查所得到的数据,分析这一嵌套结构的形成原因和影响因素。结果显示：上海市闵行区城市绿地中的雀形目鸟类分布是显著的嵌套结构,园林面积、绿地面积和水源情况都对其嵌套结构有显著影响。但是与真正岛屿上存在的群落分布嵌套结构不同,人为干扰程度对这一结构也有非常明显的影响。基于上述结果可以看出,影响上海市园林鸟类的群落嵌套结构的主要原因是栖息地的结构和人为干扰程度。因此,建议在规划和建设城市公园和绿地时,应该偏重于面积较大,植被盖度和丰富度高,结构合理的园林,并且尽量减少人为干扰。     

Bird community patterns in response to the island features of urban woodlots in eastern China

Many studies have demonstrated the changes in the spatial patterns of plant and animal communities with respect to habitat fragmentation.Insular communities tend to exhibit some special patterns in connection with the characteristics of island habitats.In this paper,the relationships between richness,assemblage,and abundance of bird communities with respect to island features were analyzed in 20 urban woodlots in Hangzhou,China.Field investigations of bird communities,using the line transect method,were conducted from January to December,1997.Each woodlot was surveyed 16 times during the year.Results indicated that bird richness was higher,per unit area,in the smaller woodlots than the larger ones,and overall bird density decreased with the increase in the size of woodlot.However,the evenness of species abundance increased with the area,and small woodlots were usually dominated by higher density species and large woodlots by medium density species.Most species occurring in the small woodlots also occurred in larger woodlots.Also,bird communities among urban woodlots showed a nestedness pattern in assemblage.These patterns implied that the main impacts of woodland habitat fragmentation are:(1) species are constricted and thus species number will increase at a given sample size;(2) as surface area decreases,the proportion of forest edge species as to interior species will increase;(3)community abundance will therefore increase per unit area but most individuals will be from a few dominant species;and (4) overall species diversity will decrease at a habitat level as well as at a region level.These patterns of community in response to the island features were therefore summarized as "island effects in community".The underlying processes of such observations were also examined in this paper.Woodlot area,edge ratio,isolation,and habitat nestedness were considered as the important factors forming the island effects in community.High heterogeneity between habitats usually contributed most to the maintenance of regional biodiversity,especially in urban woodlots.     

Bird community patterns in response to the island features of urban woodlots in eastern China

Many studies have demonstrated the changes in the spatial patterns of plant and animal communities with respect to habitat fragmentation. Insular communities tend to exhibit some special patterns in connection with the characteristics of island habitats. In this paper, the relationships between richness, assemblage, and abundance of bird communities with respect to island features were analyzed in 20 urban woodlots in Hangzhou, China. Field investigations of bird communities, using the line transect method, were conducted from January to December, 1997. Each woodlot was surveyed 16 times during the year. Results indicated that bird richness was higher, per unit area, in the smaller woodlots than the larger ones, and overall bird density decreased with the increase in the size of woodlot. However, the evenness of species abundance increased with the area, and small woodlots were usually dominated by higher density species and large woodlots by medium density species. Most species occurring in the small woodlots also occurred in larger woodlots. Also, bird communities among urban woodlots showed a nestedness pattern in assemblage. These patterns implied that the main impacts of woodland habitat fragmentation are: (1) species are constricted and thus species number will increase at a given sample size; (2) as surface area decreases, the proportion of forest edge species as to interior species will increase; (3) community abundance will therefore increase per unit area but most individuals will be from a few dominant species; and (4) overall species diversity will decrease at a habitat level as well as at a region level. These patterns of community in response to the island features were therefore summarized as “island effects in community”. The underlying processes of such observations were also examined in this paper. Woodlot area, edge ratio, isolation, and habitat nestedness were considered as the important factors forming the island effects in community. High heterogeneity between habitats usually contributed most to the maintenance of regional biodiversity, especially in urban woodlots. __________ Translated from Acta Ecologica Sinica, 2005, 25(4): 657–663 [译自: 生态学报, 2005, 25(4): 657–663]     

BIODIVERSITY RESEARCH: Nestedness for different reasons: the distributions of birds,lizards and small mammals on islands of an inundated lake

Aim We examined whether the community compositions of birds, lizards and small mammals were nested in a fragmented landscape in the Thousand Island Lake, China. We also assessed whether the mechanisms influencing nestedness differed among these taxonomic groups. Location Thousand Island Lake, China. Methods Presence/absence matrices were compiled for birds (42 islands) and lizards (42 islands) using line‐transect methods, and for small mammals (14 islands) using live‐trapping methods from 2006 to 2009. Nestedness was analysed using BINMATNEST, and statistical significance was assessed using the conservative null model 3. We used Spearman rank correlations and partial Spearman rank correlations to examine associations of nestedness and habitat variables (area, isolation, habitat diversity and plant richness) as well as life‐history traits (body size, habitat specificity, geographical range size and area requirement) related to species extinction and immigration tendencies. Results The community compositions of birds, lizards and small mammals were all significantly nested, but the causal factors underlying nestedness differed among taxonomic groups. For birds, island area, habitat specificity and area requirement were significantly correlated with nestedness after controlling for other independent variables. For lizards, habitat heterogeneity was the single best correlate of nestedness. For small mammals, island area, habitat heterogeneity and habitat specificity were significantly correlated with nestedness. The nested patterns of birds, lizards and small mammals were not attributable to passive sampling or selective colonization. Main conclusions The processes influencing nested patterns differed among taxonomic groups. Nestedness of bird assemblages was driven by selective extinction, and lizard assemblage was caused by habitat nestedness, while nestedness of small mammals resulted from both selective extinction and habitat nestedness. Therefore, we should take taxonomic differences into account when analysing nestedness to develop conservation guidelines and refrain from using single taxa as surrogates for others.     

Impacts of an invasive willow (Salix × rubens) on riparian bird assemblages in south‐eastern Australia

We explored how a woody plant invader affected riparian bird assemblages. We surveyed 15 200‐m‐long transects in riparian zones in a much‐changed landscape of eastern Victoria, Australia. Abundance, species‐richness, foraging‐guild richness and composition of birds were compared in transects in three habitat types: (i) riparian zones dominated by the invasive willow Salix × rubens; (ii) riparian zones lined with native woody species; and (iii) riparian zones cleared of almost all woody vegetation. We also measured abundance and richness of arthropods and habitat structure to explore further the effects of food resources and habitat on the avifauna. We observed 67 bird species from 14 foraging guilds. Native riparian transects had more birds, bird species and foraging guilds than willow‐invaded or cleared transects. Habitat complexity increased from cleared to willow‐invaded to native riparian transects, as did abundance of native and woodland‐dependent birds. Native shrub and trees species had more foliage and branch‐associated arthropods than did willows, consistent with a greater abundance and variety of foraging guilds of birds dependent on this resource. Willow spread into cleared areas is unlikely to facilitate greatly native bird abundance and diversity even though habitat complexity is increased. Willow invasion into the native riparian zone, by decreasing food resources and altering habitat, is likely to reduce native bird biodiversity and further disrupt connectivity of the riparian zone.     

The role of farm structure on bird assemblages around a Kenyan tropical rainforest

Although it is clear that the farmlands neighbouring fragmented forests are utilized by some forest birds, it is not clear how birds in general respond to farmland habitat mosaic. An effort was made to determine how bird density and foraging assemblages were influenced by farm structural characteristics and distance from forest edge. Thirty farms up to a distance of 12 km around Kakamega forest in western Kenya were studied. Farm structure entailed size, hedge volume, habitat heterogeneity, woody plant density, plant diversity and crop cover. Birds were surveyed using line transects and DISTANCE analyses and classified into six feeding guilds and three habitat associations. Size of farms increased away from the forest, as woody plant density, plant diversity, indigenous trees and subsistence crop cover declined. The most important farm structure variable was hedge volume, which enhanced bird species richness, richness of shrub‐land bird species and insectivorous bird density (R = 0.58, P < 0.01). Bird density increased with tree density while indigenous trees were suitable for insectivores and nectarivores. There were very few forest bird encounters. Agricultural practices incorporating maintenance of hedges and sound selection of agroforestry trees can enhance conservation of birds on farmland, though, not significantly for forest species.     

上海城市绿地冬季鸟类群落特征与生境的关系

2005年11月至2006年2月对上海市区绿地鸟类进行了调查,共记录到鸟类34种,隶属5目16科。研究发现冬季鸟类群落结构相对稳定,优势种为麻雀(Passer montanus)和白头鹎(Pycnonotus sinensis)。冬季鸟类群落多样性受多种因素的影响,其中绿地面积、乔木盖度和栖息地类型多样性是影响鸟类多样性的关键因子。聚类结果表明,面积大、生境类型丰富及人为干扰相对较少的绿地,鸟类多样性高。因此提出如下建议:(1)增加城市中植物种类,特别是乡土物种,适当提高冬季常绿乔木以及乔、灌、草的比例;(2)在绿地中尽可能多地保留自然生境;(3)在城市绿地中适当开辟湿地生境,以吸引水鸟栖息。     

Nested bird and micro-habitat assemblages in a peatland archipelago

Biotic assemblages of insular habitats are nested when poor assemblages are subsets of richer ones. Nestedness of species assemblages is frequent and may result from selective extinction or frequent colonization in insular habitats. It may also be created by a nested distribution of habitats among islands or by sampling bias. We sampled 67 isolated peatlands (7–843 ha) in southern Quebec, Canada, to measure nestedness of bird species assemblages among peatlands and assess the habitat nestedness hypothesis. Species and microhabitat assemblages were both strongly nested among peatlands. Whether sites were ranked by species richness, microhabitat richness or peatland area had no effect on nestedness. However, microhabitat nestedness was significantly reduced when sites were sorted by area rather than by microhabitat richness. As expected, if bird-microhabitat associations are responsible for the nested pattern of distribution, we found a positive correlation between the contributions of bird species and microhabitats to individual site nestedness. Nevertheless, microhabitat assemblages were significantly less nested than bird species assemblages, possibly because of frequent recolonization by birds or uneven sampling among sites. Received: 12 June 1998 / Accepted: 20 September 1998     

Edge effects on ground beetles at the woodlot–field interface are short‐range and asymmetrical

• 1 Boundaries between woodlots and agricultural habitats are numerous in temperate agricultural landscapes and influence ecological processes in both woodlots and agricultural habitats.
• 2 We aimed to determine how far the species assemblage of ground beetles in woodlot and open habitats was influenced by the presence of the woodlot–field boundary.
• 3 We studied the distribution of ground beetles on both sides of the boundaries of four woodlots along transects of pitfall traps (n = 140). The depth of edge influence (i.e. the distance from the boundary at which the presence of the boundary has no more significant influence) on the species assemblage of ground beetles in each woodlot and in each agricultural habitat was determined with nonlinear canonical analysis of principal coordinates, an ordination method that is followed by nonlinear regression of the principal coordinates on distance from the boundary.
• 4 The depth of edge influence on the species assemblages of ground beetles was asymmetrical relative to the boundary: it was generally higher and had higher variability in open habitats (14.4 ± 12.3 m) than in woodlots (4.9 ± 2.3 m). Species assemblages of ground beetles in edges were a mix between both adjacent species assemblages. Edge effects in woodlots were deeper in the woodlots exhibiting a deeper penetration of open habitat species. Symmetrically, edge effects in open habitat were deeper in the open habitats with a deeper diffusion of forest species into the open habitat.
• 5 Forest ground beetles were not threatened by edge effects. Rather, edge effects are likely to benefit agriculture, mostly through the dispersal of predatory forest species into agricultural fields.