南洞庭湖冬季鸟类群落结构及多样性分析

南洞庭湖冬季常见鸟类共４３种,隶属１０目２１科３５属,其中国家二级保护动物５种,湖南省级保护动物１６种。该地的冬候鸟２４种,留鸟１９种。东洋界鸟类１２种,古北界鸟类２种,广布性鸟类２９种。南洞庭湖冬季鸟类的多样性指数为２．０００８,均匀性指数为０．５３１９。     

广东内伶仃岛夏季鸟类群落生物多样性的研究

于1997－1999年7月10－20日,对内伶仃岛夏季鸟类群落进行了调查和研究,结果表明,34种鸟类是该岛的优势种类,又次内伶仃岛划分为5个岛类群落,并对这5个夏季鸟类群落的组成,群落间的相似性和均匀度以及各群落生物多样性做了分析和讨论。     

三峡重庆库区不同鸟类群落的物种组成及多样性研究

1996～1997年,对三峡工程重庆库区的鸟类群落物种组成和种群数量进行了调查,共调查记录库区鸟类15目48科226种,数量18929只。用鸟类数量级划分、Sorensen相似性指数、Shannon-Wiener指数和Pielou指数分析库区各种生境鸟类群落物组成和物种多样性结果表明：1）库区天然林、人工林、灌草丛和水域生境中鸟类群落的组成与农田生境具有较高的相似性,尤以人工林和农田的相似性最高;2）库区人工林生境鸟类群落物种多样性最高;3）库区由于长期以来人类活动的影响,生境日趋单一,已逐渐形成一种以农田灌丛鸟类为主的鸟类生态系统。     

采煤沉陷对鸟类群落组成及多样性的影响

采煤沉陷改变了地貌景观,使鸟类的生境发生变化,进而影响鸟类群落多样性。我们于2013年11月—2014年10月在安徽省淮南潘集的采煤沉陷区不同沉陷程度的4种生境开展鸟类调查,研究采煤沉陷导致的生境变化对鸟类群落结构的影响。共记录到鸟类13目29科79种,其中留鸟32种(40.5%),冬候鸟19种(24.1%),夏候鸟25种(31.6%),优势种为灰椋鸟Sturnus cineraceus、喜鹊Pica pica、麻雀Passer montanus和家燕Hirundo rustica。随着采煤沉陷程度的增加,物种数、个体数量、群落密度表现出轻度沉陷区<中度沉陷区<重度沉陷区的规律,多样性指数为轻度沉陷区<重度沉陷区<中度沉陷区,在地表沉陷过程中,鸟类群落结构具有不稳定性。各类生境中鸟类群落的物种组成变化明显,随着沉陷程度的增加,鸟类群落物种丰富度增加。     

北京紫竹院公园鸟类群落多样性分析

2004年9月～2005年6月在北京紫竹院公园进行鸟类群落调查.共记录到鸟类52种,隶属于11目26科.其中夏候鸟17种,冬候鸟4种,旅鸟28种,留鸟13种.鸟类的种类和数量随季节变化有明显差异.春、秋季鸟类种类丰富,秋季达到最高;冬季鸟类数量达到最高.优势种有灰椋鸟Sturnus cineraceus、麻雀Passer montanus、喜鹊Pica pica、厌喜鹊Cyanopica cyana、绿头鸭Anas platyrhynchos、鸳鸯Aix galericulata等.鸟类群落多样性指数和均匀度指数变化趋势类似,春、秋季高,冬季低,而优势度指数的变化是冬季最高,春、秋季低.鸟类多样性增加主要是由于春、秋季的候鸟迁徙.保证一定的公园面积、增加空间异质性、合理配置资源,有利于保护鸟类的多样性.     

北京小龙门林区夏季鸟类群落物种组成及多样性变化

本文研究了小龙门林区夏季鸟类群落物种组成和多样性及其在 1999年～ 2 0 0 3年时间段内的变化。通过野外设置8块样地 ,采用网捕环志、望远镜观察、鸣叫识别三种方法统计 ,得到了以下结论 :山雀科 (Paridae)、长尾山雀科 (Aegithalidae)、翁鸟科 (Muscicapidae)为该地区的优势科 ,银喉长尾山雀 (Aegithaloscaudatus)、大山雀 (Parusmajor)、褐头山雀 (Parusmontanus)、冠纹柳莺 (Phylloscopusreguloides)为该地区的优势种 ;林区鸟类物种及生物多样性丰富 ,且在研究阶段内呈现逐渐增长的趋势 ;另外 ,通过分析也发现林区内空间距离是决定不同森林生境类型间鸟类群落相似程度的主要因素 ,这些结论对于太行山生态恢复工程如何继续实施有重要意义。     

广东阴那山自然保护区鸟类群落结构及多样性

2012 年10 月－2013 年9 月, 采用固定样线法和样点法对广东阴那山自然保护区鸟类群落结构及多样性进行初步调查, 共记录鸟类175 种, 隶属14 目42 科125 属。其中, 国家Ⅰ级保护种类1 种, 国家Ⅱ级保护种类19 种。按居留类型分类, 夏候鸟34 种, 冬候鸟52 种, 留鸟78 种, 旅鸟11 种; 按动物地理区划分类, 古北界种类67 种, 东洋界种类65 种, 广布性鸟类43 种。该区域鸟类优势种32 种, 多样性指数为4.3929, 优势度为0.0204, 均匀度为0.8506。     

湖北崩尖子自然保护区夏季鸟类群落及多样性研究

2014 至2015 年每年的6—8 月, 采用样线法对崩尖子自然保护区夏季鸟类群落组成与结构进行了研究, 野外调查共记录鸟类9 目29 科 56 种, 其中国家重点保护鸟类 3 种。从居留型来看, 留鸟39 种,夏候鸟16 种, 旅鸟1种; 在地理区系构成上, 东洋种37 种(66.07%),古北种8 种(14.29%),广布种11 种(19.64%)。多样性分析结果显示,该区鸟类群落Shannon-Wiener 指数、Pielou 指数、和Simpson 指数分别为3.33、0.83 和0.95。从各生境群落多样性指数看,常绿落叶阔叶混交林中鸟类群落多样性指数最大,其次是落叶阔叶—温性针叶林,高山灌丛草甸带的多样性指数最小; 优势度指数在不同生境的变化趋势与群落多样性指数相似; 高山灌丛草甸中鸟类群落Pielou 均匀度指数最高,常绿阔叶林中的鸟类群落均匀度指数最低,旨在为崩尖子自然保护区的生物多样性保护提供科学依据。     

渭河平原地区夏季鸟类群落结构

在渭河平原咸阳地区选取有代表性的7种生境,采用样带法取样,选用Shannon-Wiener、Pielou指数和多元变量分析法进行鸟类群落结构分析。共发现63种鸟类,隶属于13目29属47科。7个样区的鸟类组成表明水域面积是影响特定鸟类（水鸟）分布的重要因子。α多样性指数和干扰程度呈线性关系（Y=2.945-0.352X)。而中等偏上的均匀度表明不同样区种群的分布较为均匀。进一步对鸟类群落结构进行聚类分析、多维尺度分析以及主分量分析后表明：按照人为干扰程度的大小将7个样区划分为3－4个群落组合;多维尺度分析的结果比聚类分析的结果更接近实际情况;在人为干扰的前提下,类似生境（相同高程或相近水域面积）鸟类群落的相似性程度并不高。     

长沙黄花国际机场鸟类群落物种多样性分析

为了获得长沙黄花国际机场鸟击防范工作所需的鸟类基础性资料,从2005年9月~2006年8月,通过对机场地区5种生境类型鸟类群落的调查与监测,记录到鸟类112种,属16目32科。其中46种属东洋界种类、45种属古北界种类、21种属广布种;留鸟46种、夏候鸟25种、冬候鸟29种、旅鸟12种。经RB频率指数测算,鸟类群落的优势种为白头鹎(Pycnonotus sinensis)、乌鸫(Turdus merula)和树麻雀(Passer montanus)。按鸟类生境分布系数划分,广布型的鸟类有44种,是该区鸟类群落组成的主体。鸟类群落的Shannon-Weiner物种多样性指数为1.607,均匀性指数为0.784。     

城市公园生境类型对鸟类群落的影响

2011年12月—2012年11月,在上海世纪公园和滨江森林公园对鸟类群落和植物群落进行调查,通过对12个植被变量进行主成分分析,将两个公园分为8种不同的生境类型。结果表明:2个公园生境构成存在显著差异,滨江森林公园灌木层植物发达的生境(Habitat with developed shrub layer,S型)以及灌木层和地被层植物都发达的生境(Habitat with developed tree layer and shrub layer,T+S型)数量显著多于世纪公园,世纪公园地被层发达的生境(Habitat with developed ground cover layer,G型)以及乔木层和地被层植物都发达的生境(Habitat with developed tree layer and ground cover layer,T+G型)数量显著多于滨江森林公园。世纪公园不同生境中鸟种数差异显著,而滨江森林公园中差异不显著。2个公园有24种共有鸟种,对共有鸟种生境利用率的配对t检验结果表明,滨江森林公园鸟类生境利用率显著高于世纪公园。对2个公园共有生境类型中鸟种数进行分析,发现滨江森林公园鹟科(Muscicapidae)鸟类种数显著大于世纪公园。根据以上结果,上海城市公园不同生境类型对鸟类群落结构存在显著影响。因此,建议在规划和建设大型城市公园时,应构建植被分层结构复杂的生境,多样化种植各类乔木,林下多样化搭配灌木。在保留供游客休憩草坪区域的同时种植各类草本植物,以此提高鸟类生境利用率,增加城市公园的鸟类多样性。     

夏季大亚湾鱼类群落结构与多样性

根据2018年8月大亚湾海域底拖网鱼类资源调查数据,分析了大亚湾夏季鱼类群落结构特征。结果表明:2018年大亚湾夏季渔获鱼类56种,隶属9目、34科、47属。其中,鲈形目(Perciformes)最多(39种,69.64%);物种组成以短吻鲾(Leiognathus brevirostris)、黄斑蓝子鱼(Siganus oramin)、拟矛尾鰕虎鱼(Parachaeturichthys polynema)、六指马鲅(Polynemus sextarius)和二长棘犁齿鲷(Evynnis cardinali)等小型低值鱼类为主;鱼类物种多样性存在明显的空间差异,表现为湾口海域最大,沿岸海域次之,湾中部海域最小。鱼类群落结构大体分为咸淡水湾内和海水广布湾口两个鱼类群组;对比1985—2017年夏季调查资料可知,30多年来大亚湾夏季鱼类群落物种多样性减小;优势种组成更替显著,由以大型中上层的经济鱼类为主演变为以小型底层、近底层的低值鱼类为主,其主要原因是人类活动对大亚湾生态系统的干扰,尤其是捕捞致使鱼类群落结构发生改变、趋向简单化。     

Relationships between vegetation and bird community composition in grasslands of the Serengeti

The Serengeti–Mara ecosystem holds one of the largest natural grasslands of the world, which is well known for its large herds of mammals. However, the bird community structure of these grasslands has hardly ever been studied. For the first time, a large‐scale study on grassland bird communities has been conducted in all typical open grasslands of the Serengeti National Park. We used ten grassland plots representing a gradient of increasing vegetation height and also including shrubs and trees to analyse the influence of vegetation structure on the composition of grassland bird communities. Three communities of breeding birds were identified in relation to (a) short grass, (b) intermediate and long grass and (c) wooded grasslands. The bird communities of intermediate, long and wooded grassland were very similar, because of identical dominant bird species. Our results suggest that breeding birds of East African grasslands exhibit two contrasting habitat relationships: (1) birds that are restricted to short grass, and (2) species that are tolerant to vegetational shifts from intermediate grass via long grass to early stages of woody vegetation. Because the vegetation is often driven beyond this range in managed tropical grasslands through high grazing pressure or through shrub encroachment, we expect that the long‐grass bird communities will not generally resist anthropogenic disturbance.     

Disturbance, selective logging and bird diversity: a Neotropical forest study

The composition and structure of bird communities, and the damage to forest structure were surveyed in northern French Guiana (northeastern Amazonia) one year and ten years after selective logging and compared with the situation in a similar undisturbed primary forest. A point-count method was used in which 937 0.25ha sample plots were censused for 20 minutes each, and their vegetation structure was measured. On average, 38% of the forest undergrowth was destroyed, then invaded by dense regrowth, and up to 63% of the canopy was substantially opened as a result of selective logging. Hunting pressure also increased due to access roads opened for logging. Among the 256 species recorded, overall bird species richness and abundance were depressed by 27–34% in the logged areas compared to primary forest. The most vulnerable guilds, which decreased by 37–98% in abundance, were mature forest understorey species, especially terrestrial ones and mixed flocks of insectivores. Hummingbirds, small gaps, vine tangles and canopy species did not decrease, nor increase significantly after logging. Only species naturally associated with dense second growth, forest edges and large gaps actually increased. Habitat specialization was the major determinant of vulnerability to logging, and, to a lesser degree, size (large) and diet (insectivorous), but foraging behaviour and rarity had little effect. Bird sensitivity to changes in logged forest structure may involve physiological intolerance, reduced food categories, increased exposure to predators, too dense understorey for their specific foraging behaviour and/or avoidance of gaps. Suggested improvements of current forest management and logging techniques for the maintenance of a higher proportion of the original biodiversity include minimizing logging damages, long rotations (>50 years) between cuts, and keeping unlogged forest patches within logging concessions.     

Changes of a forest bird community in Hong Kong of China in 10 years

The changes in the bird community structure of the largest natural secondary forest of Hong Kong over 10 years were investigated. Densities of the 10 most abundant species in 1993–1995 and 2003–2005 were compared using t-test. All resident habitat generalists showed significant decline in densities. Two forest specialists showed significant increase in densities: one is native and the other is exotic species. The trend of changes in the forest bird community of Hong Kong is mainly related to the absence of nearby forests that could act as “source” of forest dependent species to colonize the local secondary forests, and the invasion of exotic species.     

Changes of a forest bird community in Hong Kong of China in 10 years

The changes in the bird community structure of the largest natural secondary forest of Hong Kong over 10 years were investigated. Densities of the 10 most abundant species in 1993–1995 and 2003–2005 were compared using t-test. All resident habitat generalists showed significant decline in densities. Two forest specialists showed significant increase in densities: one is native and the other is exotic species. The trend of changes in the forest bird community of Hong Kong is mainly related to the absence of nearby forests that could act as “source” of forest dependent species to colonize the local secondary forests, and the invasion of exotic species.     

Effects of flooding on a wetland bird community

The Lake Izunuma–Uchinuma was extensively flooded in 1998 and vast areas (approximately 200 ha) of rice fields were submerged for the first time since the land was reclaimed in 1963. When the numbers of birds in 1998 were compared with those in normal years (1995–1997), the numbers of black-crowned night herons (Nycticorax nycticorax L.), cattle egrets (Bubulcus ibis L.) and black kites (Milvus migrans Boddaert) increased during the flooding, and the numbers of ducks, especially dabbling ducks (seven species of 11 Anas spp.) were high even after the flooding, while the numbers of the little grebe Tachybaputus ruficollis Pallas were diminished by the flooding.     

香港大埔滘天然次生林鸟类群落结构变化

观察了香港最大的大埔滘天然次生林内鸟类群落结构在10a间的变化。用t檢验比较了1993~1995年和2003~2005年间的10种数量最高的鸟类的密度变化。所有的泛生境留鸟种类的密度均呈显著减少。两种树林种类的密度有显著増加,其中一种是本土种,另一种是外来种。香港树林鸟类群落的变化趋势主要受到两个因素的影响,包括缺少有树林种类鸟居住的树林,和外来种的入侵。     

Host community structure and the maintenance of pathogen diversity

Community structure has been widely identified as a feature of many real-world networks. It has been shown that the antigenic diversity of a pathogen population can be significantly affected by the contact network of its hosts; however, the effects of community structure have not yet been explored. Here, we examine the congruence between patterns of antigenic diversity in pathogen populations in neighbouring communities, using both a deterministic metapopulation model and individual-based formulations. We show that the spatial differentiation of the pathogen population can only be maintained at levels of coupling far lower than that necessary for the host populations to remain distinct. Therefore, identifiable community structure in host networks may not reflect differentiation of the processes occurring upon them and, conversely, a lack of genetic differentiation between pathogens from different host communities may not reflect strong mixing between them.