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岛屿生物地理学理论的核心过程是岛屿物种的周转, 包括迁入与灭绝。本研究旨在探讨扩散能力差异对岛屿繁殖鸟类群落动态的影响。2007年4月至2013年6月, 采用样线法调查了千岛湖36个陆桥岛屿的繁殖鸟类, 依据扩散能力强弱将其划分为两类, 结合陆桥岛屿参数, 并运用逻辑斯蒂回归模型和最大似然法, 来研究鸟类扩散能力的不同对其周转率的影响。结果表明, 千岛湖繁殖鸟类扩散能力强的物种具有较高周转率且受岛屿参数约束较小, 而扩散能力弱的物种周转率较低且对岛屿参数变化更敏感。因此, 千岛湖陆桥岛屿繁殖鸟类的扩散能力显著影响其群落动态。  相似文献   

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A series of experiments was designed to study the effects of changes in leaf nitrogen (N) concentration on population dynamics of a range of insects associated with Rumex obtusifolius. During the study period, the N concentration in leaves fluctuated between 2 and 6% dry weight. The insects at both study sites showed a pattern of shift in time for peak population density (time‐shift). This suggests that the insect community dynamics might be closely related to the allocation and distribution of resources by the host‐plant. The elevated N concentration in the host‐plant did not change the temporal order of the peak population densities of the insects, although it may determine the time for the optimal exploitation of resources by each insect species.  相似文献   

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The genus Tetramitus is a representative amoeboflagellate group within the Heterolobosea, and currently contains over a dozen species. Here, a new heterolobosean amoeboflagellate was isolated from a freshwater pond on Dokdo Island, Korea. The amoebae have eruptive pseudopodia, no uroidal filament, and a nucleus with a central nucleolus. The length and width of the amoebae are 15.5–28.0 μm and 5.4–12.6 μm, respectively. The flagellates are conical, with 4 flagella of equal length (~10 μm). There is a discrete rostrum in the subapical region of the flagellate form. The cyst has thin endo‐ and ectocyst layers and no cyst pores. The amoeba shows slow movement at 37 °C, but does not move at 42 °C under a light microscope. Phylogenies of the 18S rRNA gene and the ITS1‐5.8S rRNA gene‐ITS2 sequence show that the strain belongs to a subclade of Tetramitus that includes Tetramitus rostratus, Tetramitus waccamawensis and Tetramitus entericus, amongst others. Nonetheless, the strain is distinct from other species in both molecular phylogenetic trees. Thus the strain isolated from the Dokdo Island is proposed as a novel species, Tetramitus dokdoensis n. sp.  相似文献   

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The biodiversity in the sub-Antarctic region is threatened by climatic change and biological invasions, which makes the understanding of distributions of biotas on sub-Antarctic islands essential. Although the distribution patterns of vascular plants and insects on sub-Antarctic islands are well documented, this is not always the case for microarthropods. This study provides the first quantitative assessment of the distribution and abundance of microarthropods on Prince Edward Island (PEI), one of two islands in the Prince Edward Island group. Microarthropod community structure differed significantly between PEI and nearby Marion Island, with only two invasive alien species found on PEI compared with Marion Island. Furthermore, species richness, abundance and community structure differed significantly between habitat types on both islands. This study emphasizes the importance of quarantine measures when visiting PEI to maintain its status as one of the more pristine islands in the sub-Antarctic region.  相似文献   

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在2012年-2013年期间对菜子湖湿地鞘翅目昆虫多样性进行调查,在不同生境、月份对该湿地的鞘翅目昆虫种类及数量进行了统计,对采集的物种进行编目,并采用Shannon-Wiener物种多样性指数、Simpson优势度指数、Pielou均匀度指数、MargMef丰富度指数对其群落多样性进行分析。结果表明:菜子湖湿地共有鞘翅目昆虫种类139种,分别隶属于29科114属,其中安徽新记录种7种。区系分析表明该湿地东洋古北共有种占优势,东洋种次之,古北种最少,其所占比例分别为62.59%、27.34%、10.07%。鞘翅目昆虫多样性分析结果显示:不同生境多样性指数高低顺序为草丛一灌木区〉农田区〉滩涂一草丛;不同月份多样性指数高低顺序为5月、7月、61月和8月。多样性、均匀性及丰富度的相关分析说明:菜子湖湿地鞘翅目昆虫多样性指数与丰富度、均匀度指数呈正相关,表明该湿地鞘翅目昆虫群落较稳定。  相似文献   

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为了掌握海南岛西海岸红树林软体动物多样性状况, 本文于2015-2016年对海南岛西海岸6个主要红树林分布区软体动物的种类组成、物种多样性和群落结构的时空变化进行了研究。共采集到软体动物57科201种, 主要优势种有珠带拟蟹守螺(Cerithidea cingulata)、绯拟沼螺(Assiminea latericea)、圆胖樱蛤(Pinguitellina cycladiformis)和斜肋齿蜷(Sermyla riqueti)等。年平均密度与平均生物量分别为324.13 ind./m²和142.88 g/m², 物种数、密度和生物量均高于北部湾沿岸的其他红树林。海南岛西海岸各红树林软体动物的密度和生物量均未呈现明显的季节变化, 软体动物密度存在空间上的显著差异。聚类分析结果显示, 在盐度、土壤结构和红树林群落存在差异的不同红树林, 软体动物种类组成相似度低。多因子AZTI海洋生物指数(M-AMBI)结果表明海南岛西海岸红树林软体动物群落未受明显扰动, 生态环境质量介于一般和优良之间, 但仍受到人类活动与外来植物入侵威胁, 因其在候鸟迁徙中的重要作用, 亟需加强管理与保护。  相似文献   

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郝树广  罗跃进 《昆虫学报》1998,41(4):343-353
该项研究通过系统调查,把稻田节肢动物群落按营养和取食关系划分为三个营养层(基位物种,中位物种,顶位物种)和不同的功能集团,在物种、功能集团和营养层三个组织层次水平上探讨了稻田节肢动物群落的结构和多样性,较全面地考察了整个群落中物种和功能集团在时间上的结构动态、功能关系和数量消长规律。结果表明:功能集团多样性与种多样性的变化趋势较一致,在群落研究中似乎可以用对功能集团的研究代替对种的研究,从而简化物种间复杂的网络关系,认为这是研究群落物种间功能关系的途径之一。营养层多样性在时间序列过程中波动性较小,所以可用于群落相似性和稳定性的分析。研究分析了中性昆虫对害虫调控的意义,认为对于天敌作用的评价应以整个群落为基础,全面考虑天敌、害虫、以及中性昆虫的数量、丰盛度、空间时间生态位等信息。  相似文献   

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Plant community may provide products and services to humans. However, patterns and drivers of community stability along a precipitation gradient remain unclear. A regional‐scale transect survey was conducted over a 3‐year period from 2013 to 2015, along a precipitation gradient from 275 to 555 mm and spanning 440 km in length from west to east in a temperate semiarid grassland of northern China, a central part of the Eurasian steppe. Our study provided regional‐scale evidence that the community stability increased with increasing precipitation in the semiarid ecosystem. The patterns of community stability along a precipitation gradient were ascribed to community composition and community dynamics, such as species richness and species asynchrony, rather than the abiotic effect of precipitation. Species richness regulated the temporal mean (μ) of aboveground net primary productivity (ANPP), while species asynchrony regulated the temporal standard deviation (σ) of ANPP, which in turn contributed to community stability. Our findings highlight the crucial role of community composition and community dynamics in regulating community stability under climate change.  相似文献   

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雅鲁藏布江流域维系着丰富而独特的生物资源, 是全球生物多样性研究的热点区域。然而, 该流域底栖动物多样性的调查却极不充分。本文于2015年10月和2016年3月对雅鲁藏布江干流(朗县至墨脱段)和主要支流的底栖动物进行了调查, 并采用单因素方差分析(one-way ANOVA)和典范对应分析(canonical correspondence analysis)等对群落多样性格局进行解析。共采集到底栖动物270种, 隶属于5门8纲20目92科, 包括昆虫纲246种, 寡毛纲14种, 腹足纲4种, 其他动物6种。春季和秋季分别采集到底栖动物184种和214种, 优势种均以喜清洁和冷水的水生昆虫为主, 包括四节蜉属一种(Baetis sp.)、花翅蜉属一种(Baetiella sp.)、蚋属一种(Simulium sp.)、小突摇蚊属一种(Micropsetra sp.)和短石蛾属一种(Brachycentrus sp.)等。全流域平均密度为939.1 ind./m2,sp.)等。平均生物量为5.44 g/m2。底栖动物的物种组成、密度和多样性在季节和区域之间存在一定差异, 支流的多样性显著高于干流。典范对应分析显示, 海拔、流速、河宽和底质类型等环境因子是影响雅鲁藏布江流域底栖动物群落结构的关键环境因素, 而大峡谷地区多变的气候类型和地理阻隔是造成群落变化的根本原因。本研究可为雅鲁藏布江流域底栖动物多样性评估和环境监测提供重要的基础和参考。  相似文献   

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葡萄是上海地区重要的经济水果,为探明上海葡萄种植园中昆虫种群组成,本研究在2017-2018年间,通过搜捕法、马氏网诱集法和黄色粘纸诱集法,对上海市嘉定区、奉贤区、青浦区、浦东新区、崇明岛进行了昆虫种群调查,共采集并鉴定昆虫7目65科123属182种,明确了上海地区葡萄种植园内主要害虫、天敌昆虫及环境昆虫的种类,并对上海葡萄园的昆虫种群结构和多样性进行了分析。  相似文献   

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Gall wasps (Hymenoptera: Cynipidae) are phytophagous insects that often go unnoticed; however, when they are introduced to a new area or released from their natural enemies, they have the capacity to outbreak and cause extensive foliar damage. One such outbreaking pest, Zapatella davisae (Cynipidae: Cynipini), causes significant damage and mortality to black oak, Quercus velutina, in the northeastern United States. In this study, we aimed to identify the parasitoid community associated with Z. davisae, compare differences in percent parasitism of Z. davisae in Cape Cod and Long Island, and determine which parasitoid species contribute most to parasitism in each region. From both locations, we reared parasitoids, identified morphological groups, analyzed percent parasitism rates for each group, and used DNA barcoding to provide species‐level identifications. On Long Island, there was nearly 100% parasitism in 2015 followed by a near total collapse of the population in 2016. In contrast, parasitism rates were lower and remained consistent on Cape Cod between 2015 and 2016, which may explain the greater canopy damage observed in that region. Species of Sycophila were the dominant parasitoids, with one species Sycophila nr. novascotiae representing ~65% of reared parasitoids from Long Island, and two species of Sycophila (S. nr. novascotiae and S. foliatae) with near equal representations on Cape Cod. In order to manage an insect pest, it is important to understand factors that influence its mortality and survival. An understanding of how these infestations progress overtime can help predict the impact that newer infestations in Nantucket, MA, and coastal Rhode Island will have on black oak populations and will aid in the management of this rapidly spreading gall wasp pest.  相似文献   

13.
豚草发生地土壤昆虫群落结构及动态   总被引:6,自引:0,他引:6  
孙刚  房岩  殷秀琴 《昆虫学报》2006,49(2):271-276
采用分层取样法、大类群分类法和数理统计方法,研究了普通豚草Ambrosia artemisiifolia和三裂叶豚草A.trifida发生地土壤昆虫的群落结构及动态。共采集土壤昆虫46个科(成虫与幼虫分开单列),隶属于12个目,其中弹尾目个体数占绝对优势(占土壤昆虫总个体数的80.879%),其次是膜翅目(8.765%)、鞘翅目幼虫(3.951%)和双翅目虫(3.093%),其余合计占3.312%。在46个科中,优势类群有3科:棘跳虫科(Onychiuridae)(占土壤昆虫总个体数的32.756%)、鳞跳虫科(Tomoceridae)(18.869%)和节跳虫科(Isotomidae)(18.178%)。土壤昆虫个体数和类群数,随着豚草生长季的推进而增加,8月达到最高值。豚草降低了土壤昆虫的个体数量和群落多样性,根据逐月方差分析和多重比较,8月和9月对照样地土壤昆虫个体数量和多样性指数均显著高于豚草样地。豚草表现出对某些土壤昆虫类群的驱避作用,步甲科(Carabidae)成虫、拟花萤科(Dasytidae)幼虫、叶蝉科(Jassidae)、阎甲科(Histeridae)和管蓟马科(Phloeothripidae)在豚草整个生长季从未在豚草样地中出现。豚草对于土壤昆虫的抑制作用在豚草纯群落和植物生长旺季更为明显。土壤昆虫的垂直分布具有明显的表聚性。  相似文献   

14.
1. If fungivorous insect diversity is maintained by host specialisation on particular fungi, it should be higher in the tropics than in temperate or boreal regions owing to high macrofungus species diversity. 2. To reveal the community and food web structure of fungivorous insects on bracket fungi, fungivorous insects were collected from 427 fruiting bodies belonging to 22 genera throughout the development and deterioration process in a 3‐ha plot of lowland dipterocarp tropical rain forest on Borneo Island. 3. Eight hundred and twenty‐nine individuals of 82 coleopteran species in 13 families from 111 fruiting bodies of 15 fungal genera were collected. Tenebrionidae and Staphylinidae were most common. Fifty‐three and 19 insect species were observed on Ganoderma and Phellinus, respectively. The numbers of insect species and individuals on a particular fungal genus were positively correlated with the abundance of that fungal genus. 4. Quantitative food web analysis revealed a high degree of specialisation at the whole‐community level. At least 65% of insect individuals were observed on Ganoderma at every stage of development and deterioration. Diverse insects coexist on one dominant fungal genus, Ganoderma, in contrast to our hypothesis. 5. The high abundance of Ganoderma fruiting bodies, which lack obvious defences against insect feeding, probably influences the bracket fungus–insect food web in this tropical rainforest.  相似文献   

15.
通过对转基因耐除草剂(EPSPS)抗虫(Cry1Ab)玉米转化体‘DBN9936’、受体玉米‘DBN318’、常规玉米‘先玉335’和喷施除草剂的转化体‘DBN9936’玉米田中节肢动物种类及数量的调查, 评价转基因玉米对田间节肢动物群落多样性的影响。2015年和2017年我们采用直接观察法、陷阱调查法和剖秆法对田间节肢动物进行调查, 采用聚类分析、物种累积曲线等方法对数据进行分析, 并比较了4个处理玉米田节肢动物群落的Margalef丰富度指数、Shannon-Wiener多样性指数、Simpson多样性指数、Pielou均匀度指数、优势集中性指数和群落相似性指数的差异及其随时间变化的规律。调查期间共记录节肢动物20目80科; 转化体玉米‘DBN9936’ (2015: 10.3 ± 2.6头, 2017: 3.3 ± 1.7头)和喷施除草剂的转化体玉米‘DBN9936’ (2015: 6.0 ± 1.5头, 2017: 17.0 ± 0.6头)上鳞翅目昆虫的数量明显低于受体‘DBN318’ (2015: 20.0 ± 3.2头, 2017: 24.0 ± 6.0头)和‘先玉335’ (2015: 21.0 ± 8.9头, 2017: 26.7 ± 2.0头); 物种累积曲线呈典型的抛物线, 各类玉米田间总体物种丰富度差异较小; 玉米生育期节肢动物调查结果累计数量的功能团组成及其丰富度、多样性、均匀度、优势集中性间均无明显的差异, 各类指数随时间变化的动态趋于一致, 群落间相似性程度较高。转基因玉米‘DBN9936’对鳞翅目害虫有明显的抗性, 对非靶标节肢动物无显著的影响, 对田间节肢动物的群落多样性、均匀度、丰富度、优势集中性等没有明显的影响。  相似文献   

16.
Predation of insects by feral cats (Felis silvestris catus) on a heterogeneous oceanic island (La Palma, Canary Islands) was studied. A total of 127 invertebrates were identified in the analysis of 500 scats (100 from each habitat of the Island). Invertebrates appear in 18.00% of the scats, representing an insignificant percentage of the total consumed biomass by feral cats on La Palma Island (0.05%). Insects were the most common invertebrate prey both in percentage of occurrence (90.6%) and invertebrate biomass (93.53%), with a total of 115 prey items. Orthoptera, Lepidoptera and Coleoptera were the main prey groups. Among the five main habitats present in La Palma Island, the temperate forest shows the lowest consumption of invertebrates, although insect consumption did not show statistical differences. However Orthoptera and Lepidoptera were more frequently preyed on in the pine forest and in the xerophytic shrub, respectively. Moreover, applying the Simplified Morisita index, a different insect composition of the diet was observed among habitats. Although, none of insects predated by feral cats are threatened, the identification of invertebrate component of the feral cats’ diet is an important tool for the correct understanding of predation significance and to prevent damage to endangered insect species.  相似文献   

17.
This study represents the first comprehensive assessment of the population dynamics and residency of common bottlenose dolphin around Reunion Island (southwest Indian Ocean). Understanding dynamics and movement patterns of this local population is essential to guide effective conservation efforts, notably in a context of growing dolphin-watching activities. Dedicated surveys based on photo-identification methods were conducted over 6 years (2010–2015). The species was present year-round, in groups of 25 individuals on average (1–150). Jolly-Seber mark-recapture models resulted in a population estimate of 254 individuals (95% CI = 191–337) and an apparent annual survival rate of 0.83. The population was almost equally split into three residency patterns: residents (33.1%), long-term visitors (32.6%), and short-term visitors (34.3%, including transients, i.e., individuals only seen once [14.9%]), suggesting that the majority of the population showed a moderate-to-high level of residency in the study area. Individuals from the three residency patterns associated randomly, mixing together and forming a single community. Models based on the lagged identification rate indicated emigration and reimmigration to the survey area, with some individuals occupying the study area for about 2 years (832 days), and remaining outside for an average of 276 days, probably exhibiting larger home ranges and extensive movement behavior.  相似文献   

18.
为探究片段化生境中木本植物种子雨的基本特征,该研究根据2015—2020年(研究期间)在千岛湖样岛上的植物群落长期监测样地内每月收集的种子雨数据,采用Kruskal-Wallis检验对木本植物的种子雨密度进行年际差异分析,对不同传播方式物种的种子雨密度进行月份间差异性分析,并利用线性混合效应模型,探究岛屿空间特征(岛屿面积、距最近岛屿的距离、距大陆的距离)以及气候因子(0 ℃以上积温、降水量)对木本植物以及不同传播方式物种的种子雨密度的影响。结果表明:(1)2015—2020年6年间,在29个样岛用240个收集器共收集到877 178粒木本植物的成熟种子,属于26科40属52种。(2)动物传播是木本植物主要的种子传播方式,不同传播方式物种的种子雨时间动态存在较大差异。(3)木本植物的种子雨年密度与岛屿面积和年积温呈显著正相关,与年降水量呈显著负相关。(4)自主传播物种的种子雨月密度与距最近岛屿的距离呈显著正相关,而动物传播物种的种子雨月密度则与距大陆的距离呈显著正相关,风力传播物种的种子雨月密度与月积温呈极显著正相关。综上表明,生境片段化通过岛屿空间特征影响了木本植物种子雨的时间动态。  相似文献   

19.
【目的】大豆蚜Aphis glycines(Matsumura)是危害我国大豆产量的重要刺吸式害虫,茄无网蚜Acyrthosiphon solani(Kaltenbach)是近年来在大豆田发生逐渐呈上升趋势的刺吸式害虫,蚜虫的发生动态严重影响大豆的产量和品质,本试验调查了马铃薯-大豆、玉米-大豆邻作种植模式对大豆田刺吸式害虫及其他主要害虫的种群动态的影响,为精准使用农药防控蚜虫提供依据。【方法】采用系统调查的方法,研究大豆田刺吸式害虫以及天敌的种群动态,在哈尔滨香坊农场进行马铃薯-大豆、大豆-玉米邻作的种植模式,对其大豆田中大豆蚜、茄无网蚜等刺吸式口器的害虫及天敌动态发生数量进行调查。【结果】2014年与2015年玉米-大豆、马铃薯-大豆种植模式的大豆田中的大豆蚜数量明显低于对照田,2014年玉米-大豆差异更显著,2015年马铃薯-大豆差异性显著。2014年与2015年玉米-大豆、马铃薯-大豆邻作种植模式的大豆田中的茄无网蚜数量显著低于对照田。而2014年8月温度低于2015年虫量相对高于2015年,虫量高时天敌总群动态也相对较高,达到调控作用。【结论】玉米-大豆、马铃薯-大豆邻作种植模式能够起到减少大豆蚜和茄无网蚜的为害的作用,并能够减少农药的使用量。  相似文献   

20.
We examined long‐term changes in the macroalgal vegetation at Stora Bornö Island in the inner Gullmar Fjord on the Swedish Skagerrak coast. This was made possible by access to a 1941 diving investigation. The same sites were reinvestigated in 1998. Community composition and depth distributions of species were compared and changes were analyzed with focus on functional groups (size, thallus shape, and life‐history traits). We discovered a significant decrease in the depth extension of macroalgal species and a dramatic decline of species richness in the lower littoral (below 16 m of depth) compared with 57 years earlier. Ordination analysis revealed that there was a significant difference in the community composition between the two study periods. In general, small (<10 cm), thin, filamentous, and aseasonal ephemerals increased in relative abundance, whereas larger (>10 cm), coarsely branched, and perennial algae decreased. Calibrations of individual species to local sediment cover, using canonical correspondence analysis, indicated that part of the change in species composition was related to sediment load. Furthermore, large‐scale climate differences (NAO Winter Index) between the study periods indicated a higher impact of Baltic Sea and Kattegat water in the nutrient dynamics of the fjord in the 1998 study. We concluded that the observed long‐term changes in the macroalgal community at Stora Bornö Island were consistent with an increased nutrient availability.  相似文献   

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