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1.
三沙湾浮游动物生态类群演替特征 总被引:4,自引:0,他引:4
根据2010年6月-2011年5月三沙湾海域5个航次海洋综合调查资料,对三沙湾浮游动物种群特征进行分析,并与我国不同纬度海湾生态类群结构进行比较.探讨三沙湾海域浮游动物生态类群季节变化特征及其受水团季节变化的影响.研究结果表明:4月和5月三沙湾海域主要受到浙闽沿岸流影响,生物多样性H'指数分别为2.03和2.02;种类数分别仅为17种和19种,明显低于6月、8月和10月;浮游动物生态类群以暖温带近海种为主;优势种种类数少,单一优势种优势性明显,4月中华哲水蚤丰度占浮游动物总丰度的65.03%;群落结构特征与同期我国长江口浮游动物区系特征相似.6月三沙湾海域受到浙闽沿岸流和台湾暖流共同影响,同时因闽北雨季导致大量大陆径流汇入,使得该月浮游动物种群结构复杂,生物多样性指数和种类数全年最高,为3.12和45种,与5月相比,种类更替明显,物种更替率为69.39%;亚热带近海种丰度百分比最高(73.03%),亚热带外海种种类数百分比次之(48.89%),是海域浮游动物生态类群由以暖温带近海种为主向以亚热带外海种为主的过渡时期.8月和10月浙闽沿岸流消失,三沙湾海域受台湾暖流控制,海水温度和盐度升高,生物多样性指数和种类数均略低于6月;生态类群结构以亚热带外海种为主;优势种特征表现为种类数多而各个优势种丰度较低;浮游动物群落结构特征与南海北部海域浮游动物组成极为相似. 相似文献
2.
浙江三门湾浮游动物优势种空间生态位 总被引:7,自引:0,他引:7
生态位与种间竞争、资源利用密切联系,体现了物种在群落中利用资源的能力.为探明三门湾浮游动物分布格局的形成和影响因素,分别采用Shannon公式和Petrailis指数测定了浮游动物优势种生态位宽度和生态位重叠,并通过典范对应分析研究生态位分化状况.结果表明:百陶带箭虫、背针胸刺水蚤、短尾类幼虫等沿岸种的空间生态位较宽,而肥胖软箭虫、中华假磷虾等外海种的空间生态位较窄;具有捕食 被捕食关系的不同类群物种(如箭虫、仔鱼和水母分别与桡足类)有较高的生态位重叠,而同一类群物种(如桡足类及箭虫)间的生态位重叠值较低;浮游动物分布受温度、盐度和叶绿素a的影响较大,受营养盐影响较小.浮游动物空间生态位与生活类型、种间竞争、摄食等多种因素相关.
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3.
研究于2019年春、夏、秋、冬四季对保安湖进行了水样采集, 基于宏基因组测序, 在优化物种鉴定和丰度计算方法的基础上, 考察了保安湖浮游动物的多样性、群落结构及其影响因素。共鉴定到浮游动物OTU 374种, 其中原生动物282个; 枝角类45个; 桡足类26个; 轮虫21个。从季节来看, 夏、秋季保安湖的浮游动物多样性高; 从湖区来看, 肖四海和主湖区浮游动物多样性高。季节因素对保安湖浮游动物群落结构的影响高于湖区影响。保安湖营养状态为中营养型, 水体温度、叶绿素a是影响保安湖浮游动物群落结构的主要环境因子, 不同类群与环境因子相关性不同, 总体可分为5类。其中原生动物优势类群为混合营养的纤毛虫和丝足虫, 同硝氮、化学需氧量、温度有明显的相关性, 而枝角类和桡足类同环境因子的关系较为相似, 与溶氧、叶绿素a、正磷酸盐存在明显相关。研究利用宏基因组方法对保安湖浮游动物多样性开展了研究, 为从浮游动物这一角度来理解保安湖这一江湖阻隔型湖泊的生物多样性的变化提供了支撑。 相似文献
4.
生物多样性评价工作是生物多样性保护的基础,而替代指标的应用是在环境影响评价中实现生物多样性快速评价的重要方法之一.本文介绍了生物多样性替代指标的概念,分析了不同生物类群之间广泛存在的相关性,总结了大尺度上兽类、鸟类、维管束植物物种数的经验比例(1:5:50).对目前可供使用的生物多样性替代指标进行了系统整理和分类,将其划分为生物类替代指标(包括指示类群、功能类群和珍稀濒危类群)和生境类替代指标(包括环境因子、景观格局和自然圣境).对不同指标的替代机理、有效性、使用方法和适用范围等进行了归纳,探讨了增强生物多样性替代指标应用有效性和评价精度的主要途径.研究可为保护地规划、生物多样性监测和环境影响评价等领域开展生物多样性快速评价,以及环境评价制度中生物多样性影响评价的完善提供参考. 相似文献
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为了验证生物多样性地理格局的几个重要假说,即种-面积关系、水分-能量动态假说、几何限制(中域效应)假说和生境异质性假说,作者以长江三峡库区维管植物物种丰富度沿海拔梯度的分布格局为例,采用多元回归和方差分解方法,研究了面积、气候、几何限制、地形异质性对多样性垂直格局的独立影响和协同作用,及其对各植物类群(不同分布宽度、不同分布区类型和不同生长型)影响的差异.结果表明,三峡库区各种植物类群的物种丰富度随着海拔上升均呈先升后降的单峰格局.水分-能量动态假说对多样性格局有很强的解释能力,其总的解释力(>93%)明显高于其他所有解释机制.但对于很多植物类群而言,水分和能量的解释力中有很大一部分属于几何限制、面积及地形异质性等因素的协同作用.几何限制对分布宽度大的物种的多样性格局解释力很强,但对分布宽度小的物种作用很小;面积自身对物种丰富度解释力较强,但在考虑了其他环境因素的影响时,仅对少数植物类群有解释力;地形异质性自身对多样性的解释能力很弱,但在多元回归模型中起着必要的作用.综合来看,水分-能量动态是解释三峡库区植物多样性垂直格局的最重要的机制.几何限制的作用随着物种分布宽度减小而递减;地形异质性虽然对多样性垂直格局的影响较弱,但也是一种必要的补充解释机制;由于面积与气候、几何限制等因素存在强烈的共线性,面积对植物多样性垂直格局的相对作用大小还需要进一步的系统比较研究. 相似文献
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瓯江口夏、秋季浮游动物种类组成及其多样性 总被引:2,自引:0,他引:2
依据2007年6和9月瓯江12水域两个航次的浮游动物调查资料,研究瓯江口浮游动物种类组成和多样性特征,并探索水团等因素对浮游动物优势种及物种多样性分布的影响.结果表明:调查水域共鉴定出浮游动物76种(不含18种浮游幼体和仔鱼),隶属于7门8纲20目41科,其中桡足类是最主要的优势类群;瓯江口水域浮游动物主要由亚热带种构成;就盐度适应而言,浮游动物种类数以外海种居多,而近海种在浮游动物总丰度中占有明显优势;秋季浮游动物种类数显著高于夏季;秋季的Shannon-Wiener多样性指数(2.89)明显高于夏季(2.23),这与秋季物种数较高有关;夏季水团交汇处的大门岛邻近水域多样性指数最高,秋季该水域多样性指数呈现从河口到外海逐渐增加的趋势. 相似文献
7.
中国裸子植物的物种多样性格局及其影响因子 总被引:1,自引:0,他引:1
物种多样性的大尺度空间格局是宏观生态学和生物地理学研究的核心问题之一。本文利用中国裸子植物分布数据, 结合气候、地形等环境信息, 分析了中国裸子植物物种多样性的大尺度格局及其影响因素, 比较了不同类群之间物种多样性格局和主导因子的差异, 并探讨了裸子植物在植物区系中所占比重的地理格局。结果表明, 中国裸子植物的物种多样性总体上呈现南高北低的趋势, 物种多样性在横断山区最高。在裸子植物的三个主要类群中, 松柏亚纲的物种多样性格局与整体相似, 买麻藤亚纲的多样性高值区则出现在中国西北部的干旱地区, 苏铁亚纲的分布区较为狭窄, 主要集中在南方地区。线性回归分析结果表明, 空间异质性和降水因子对中国裸子植物多样性格局的解释率最高, 末次冰期以来的气温变化、海拔高差和能量因子次之。这表明中国裸子植物物种多样性的格局受到了多种因素的影响, 其中空间异质性和降水因子影响最大。进一步分析发现, 物种多样性格局的主导因子在不同类群之间具有显著差异, 这可能反映了这些类群的进化历史以及生理适应的差异。裸子植物与被子植物的比例具有明显的空间格局: 在东部、南部气候环境优越的地区, 裸子植物与被子植物的比例低于0.06; 而在西部、北部等气候环境比较恶劣的地区, 裸子植物的比例则显著上升。回归分析表明, 能量和水分因子显著影响了裸子植物与被子植物的比例。随着能量的降低和降水的减少, 裸子植物与被子植物的比例会显著升高, 这可能是由于被子植物在温暖湿润地区具有较强竞争优势, 但裸子植物对极端环境具有更好的适应。 相似文献
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淡水浮游植物功能类群分类法的提出、发展及应用 总被引:2,自引:0,他引:2
浮游植物分类方法是揭示浮游植物群落演替规律、开展淡水生态研究的工作基础和重要工具.林氏分类法和分子鉴定法在生态学应用上存在的不足促进了浮游植物功能类群分类法的发展.功能类群分类法是一种以浮游植物个体生态学为依据的生态分类法.本文概述了浮游植物功能类群(functional group,FG)、生态功能类群(morpho-functional group,MFG)和形态功能类群(morphology-based functional group,MBFG)等浮游植物分类方法的理论基础和分类依据,分析比较了这3种分类方法的优势与不足,认为FG是目前应用于水生生态学研究和水环境生物评价中相对适用的浮游植物分类方法.介绍了功能类群分类法在国内外淡水浮游植物生态学研究中的应用现状,简述了以FG为基础提出的Q指数法和Q-R指数法两种水质评价法的评价标准及存在的不足.
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9.
《生态学杂志》2015,(7)
轮虫是浮游动物中的重要类群,开展轮虫种群遗传结构及系统地理格局研究对更好地理解种群分化、物种形成、生态适应和历史气候变化等进程具有重要意义。关于轮虫种群的系统地理格局主要包括两种不同的观点:一种观点认为种群的快速增长及其建群效应使得轮虫种群表现出高度的遗传分化和显著的系统地理格局;另一种观点认为,由于浮游动物具有高度的拓殖能力和局域性适应,轮虫种群间不具有系统地理格局。轮虫的种群遗传结构存在着季节变化,这可能会干扰我们对浮游动物系统地理格局的正确认识。本文简述了轮虫种群遗传结构及系统地理格局的研究现状,并对轮虫种群遗传结构及系统地理格局研究进行了展望。 相似文献
10.
烟台近海浮游动物优势种空间生态位研究 总被引:2,自引:0,他引:2
根据2018年春、夏季烟台近海海域的调查资料,以浮游动物优势种(类)为研究对象,运用Levins公式和Pianka指数分析了浮游动物优势种(类)的生态位宽度和生态位重叠程度,采用冗余分析(RDA)研究了影响浮游动物优势种(类)空间生态位分化的主要因素。研究结果表明,浮游幼虫和桡足类是烟台近海浮游动物群落结构的主要组成群体,春、夏季浮游动物优势种(类)更替率为73.33%。依据烟台近海浮游动物优势种(类)的生态位宽度值,可将其划分为广生态位、中生态位和窄生态位三大类群,广生态位种类为浮游动物优势种(类)的主要构成群体,春季代表种类有短角长腹剑水蚤(Oithona brevicornis)、拟长腹剑水蚤(Oithona similis)等,夏季代表种类有小拟哲水蚤(Paracalanus parvus)、克式纺锤水蚤(Acartia clausi)等。生态位重叠指数与物种分布的环境位点的重合情况密切相关,广生态位种类之间的生态位重叠程度要高于窄生态位种类与其他种类之间的生态位重叠程度。RDA分析表明,春季影响浮游动物优势种(类)空间生态位分化的主要因素为海水温度、盐度和无机氮(DIN),夏... 相似文献
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12.
The influence of consumer diversity and indirect facilitation on trophic level biomass and stability 总被引:2,自引:0,他引:2
Christopher F. Steiner Tara L. Darcy-Hall Nathan J. Dorn Erica A. Garcia Gary G. Mittelbach Jeremy M. Wojdak 《Oikos》2005,110(3):556-566
The relationship between species diversity and the stability and production of trophic levels continues to receive intense scientific interest. Though facilitation is commonly cited as an essential underlying mechanism, few studies have provided evidence of the impact that indirect facilitation may have on diversity–ecosystem functioning relationships. In this laboratory study, we examined the effect of zooplankton species diversity on trophic structure (total algal and zooplankton biomass) and temporal stability of total zooplankton biomass. We utilized four species of pond zooplankton grown in either monoculture or in polyculture. When comparing responses in polycultures with responses averaged across monocultures, a positive effect of diversity on total zooplankton biomass was observed. This occurred as a result of positive facilitative effects among competing zooplankton. Daphnia pulex , a biomass dominant in monoculture, was negatively affected by the presence of interspecific competitors. In contrast, Diaphanosoma brachyurum , a species that performed poorly in monoculture, was strongly and positively affected by the presence of interspecific competitors, driving positive diversity effects on total zooplankton biomass. Positive temporal covariances among zooplankton were detected in several polyculture replicates, increasing temporal variability of total zooplankton biomass. However, this destabilizing effect was weak relative to effects of high biomass yields in polyculture which caused temporal biomass variability (as measured by the coefficient of variation) to be lower in polyculture relative to monocultures. Zooplankton diversity effects on total algal biomass were not detected. However, increased zooplankton diversity significantly altered the size structure of algae, increasing the relative abundance of large, grazer-resistant algae. 相似文献
13.
千岛湖浮游动物的群落结构 总被引:14,自引:0,他引:14
研究了贫-中营养型的大型,深水湖泊--浙江千岛湖浮游动物的群落结构,包括种类组成,种群动态,现存量及群落多样性指数。在1a的研究中,共发现139种浮游动物(27种原生动物,70种轮虫,26种枝角类和16种桡足类)。根据年平均密度,各类浮游动物的优势种分别为褶累枝(Epistylis plicatilie),螺形龟甲轮虫9Keratella cochlearis),透明蚤(Daphnia hyalina)和一种中剑水蚤(Mesocyclops notius)。轮虫和枝角类群落多样性指数随着水体透明度的增大呈下降的趋势;采样站变异下,枝角类群落多样性指数与其种类数和密度呈显著的正相关关系;月份变异下,桡足类群落多样性指数与其密度呈显著的正相关关系。 相似文献
14.
Nutrient dependent effects of consumer identity and diversity on freshwater ecosystem function 总被引:1,自引:0,他引:1
1. Over the past decade, ecologists have tried to determine how changes in species composition and diversity affect ecosystem structure and function. Until recently, the majority of these studies have been conducted in terrestrial ecosystems and have not taken into account environmental variability. The purpose of this research was to determine how species identity and diversity in the freshwater zooplankton affected biomass of algae and zooplankton at two levels of nutrient enrichment.
2. Several species of cladocerans were grown alone and together in microcosms at both ambient and raised phosphorus concentrations to determine if the effects of consumer identity and diversity were nutrient dependent.
3. Total zooplankton biomass was greater, while algal biomass was lower, in mixed culture than in monoculture. The effects of zooplankton diversity on algal biomass, however, were only observed at raised phosphorus concentrations, suggesting that diversity effects were nutrient dependent. Specifically, diversity effects appeared to be related with biological mechanisms such as complementarity in resource use and/or facilitation.
4. More diverse communities of zooplankton appear to be better able to control algae than single species of zooplankton at high nutrient concentrations; therefore, zooplankton diversity may provide a buffer against eutrophication in freshwater ecosystems. 相似文献
2. Several species of cladocerans were grown alone and together in microcosms at both ambient and raised phosphorus concentrations to determine if the effects of consumer identity and diversity were nutrient dependent.
3. Total zooplankton biomass was greater, while algal biomass was lower, in mixed culture than in monoculture. The effects of zooplankton diversity on algal biomass, however, were only observed at raised phosphorus concentrations, suggesting that diversity effects were nutrient dependent. Specifically, diversity effects appeared to be related with biological mechanisms such as complementarity in resource use and/or facilitation.
4. More diverse communities of zooplankton appear to be better able to control algae than single species of zooplankton at high nutrient concentrations; therefore, zooplankton diversity may provide a buffer against eutrophication in freshwater ecosystems. 相似文献
15.
围圈养鱼对浮游动物多样性的影响 总被引:7,自引:1,他引:6
1993-1994年在保安湖主体湖区开展围圈养殖草鱼对浮游生物多样性影响的研究,包括围圈内外浮游动物种类组成、密度、生物量和多样性指数的季节变化等。分析表明,围圈内共有常见浮游动物64种,围圈外共有常见浮游动物55种。围圈内外浮游动物的年平均密度分别为3738和3196ind/L,年平均生物量分别为0.8177和0.8135mg/L,年平均多样性指数分别为3.3808和2.9717.研究结果表明:围圈养殖草食性鱼类对浮游动物现存量以及多样性指数无显着影响。
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16.
南沙群岛美济礁海域夏季浮游动物群落特征 总被引:7,自引:0,他引:7
浮游动物是珊瑚礁生态系统中的重要组成部分,但国内相关研究相对较少。利用2012年7月在南沙群岛美济礁海域开展的13个站次的海洋生物调查数据,对美济礁浮游动物的群落特征进行研究,表明:(1)美济礁浮游动物种类组成丰富,共出现15个类群138种(类)浮游动物;(2)优势种组成复杂、区域变化明显,单一种的优势度不高;(3)浮游动物平均密度和湿重生物量分别为117.70个/m3、69.01 mg/m3,浮游幼虫在总密度中所占比例最大;(4)浮游动物非常丰富,多样性程度较高。平均丰富度、多样性指数和均匀度分别为4.93、3.33和0.67;(5)浮游动物可划分为2个群落,分别为潟湖-礁坪区群落和向海坡群落;(6)受珊瑚礁不同生物地貌带的空间异质性和水动力条件的影响,美济礁浮游动物群落区域差异明显。潟湖区浮游动物多样性较高,生物量最低;礁坪区浮游动物数量大,但分布不均匀,且多样性水平最低;向海坡区浮游动物种类最多、多样性非常丰富,但栖息密度最低。 相似文献
17.
The species composition,biomass,abundance,and species diversity of zooplankton were determined for samples collected from August 2002 to May 2003 from 14 stations in Yueqing Bay,China.Phytoplankton growth rate and microzooplankton grazing rate were obtained by using the dilution method developed by Landry and Hassett.The spatial and temporal variations of zooplankton and its relationship with environmental factors were also analyzed.The results showed that the zooplankton in the Yueqing Bay could be divided into four ecotypes,namely coastal low saline species,estuary brackish water species,offshore warm water species,and eurytopic species.A total of 75 species of zooplankton belonging to 56 genera and 17 groups of pelagic larva were identified in the Yueqing Bay.The coastal low saline species was the dominant ecotype in the study area,and the dominant species were Labidocera euchaeta,Acartia pacifica,Acrocalanus gibber,Pseudeuphausia sinica,and Sagitta bedoti among others.There was considerable seasonal variation in zooplankton biomass and abundance in the surveyed areas.The peak biomass appeared in August,descending in November and in May,and the lowest biomass appeared in February.Similarly,the highest abundance of zooplankton was observed in August,with the abundance descending in the following months:May,November,and February.There were similar horizontal distribution patterns for the biomass and the abundance of zooplankton.They both increased from the upper to the lower bay in February and May,but decreased from the upper to the lower bay in August.Biomass and abundance were evenly distributed in the Yueqing Bay in November.Moreover,there was marked seasonal variation in the species diversity of zooplankton,which conformed to the abundance of zooplankton.Results of the dilution experiments indicated that there was grazing pressure of microzooplankton on phytoplankton in the Yueqing Bay throughout the year though the rate of microzooplankton grazing on phytoplankton varied seasonally.Phytoplanktons were growing at 0.26-2.07/d and grazed by microzooplankton at a rate of 0.15--0.48/d in different seasons. 相似文献
18.
Productivity and community structure of phytoplankton and zooplankton are influenced by hydrologic disturbances in many ways. In a recent modeling study it was suggested that pulsed inflows might enhance zooplankton performance, curb accumulation of phytoplankton accumulated biomass, and promote phytoplankton species diversity. We tested these predictions by performing microcosm experiments on natural plankton assemblages from the Nueces Delta, TX, USA. On three occasions (March, June, and September 2001), experiments of semi-continuous and flow-through design were conducted using natural plankton assemblages. We investigated the effect of two different inflow and nutrient loading regimes on zooplankton biomass, and phytoplankton biomass and diversity, i.e., continuous and pulsed inflows of 3 day frequency. Despite differences in initial community structure on these three occasions, as well as the very different communities that arose between experimental designs, our findings showed that pulsed inflows altered plankton dynamics. In all cases, pulsed inflows resulted in greater zooplankton biomass. In most cases, pulsed inflows resulted in lower phytoplankton biomass and higher diversity. We speculate that greater phytoplankton diversity in the pulsed flow treatments favored selectively feeding zooplankton, whose better performance prevented higher accumulation of phytoplankton biomass. 相似文献
19.
The effects of straw burning, exposure conditions and exposure durations on the diversity of zooplankton resting eggs were
examined by hatching resting eggs in sediment collected from rice fields in Pathum Thani province, Thailand. Well-mixed surface
sediment samples from with- and without straw burning paddies were stored under three conditions, (4°C and darkness; 28–40°C
and darkness; and 28–40°C and light), for different periods of time (0, 2, 4, 6, 8, 10 and 12 months). Thirty zooplankton
species were identified from hatching experiments. Of these, 25 species were Rotifera, 3 were Cladocera, 1 was Ostracoda and
1 was Copepoda. Repeated Measurement analysis showed that straw burning significantly decreased the number of zooplankton
species, the zooplankton abundance and zooplankton diversity (P = 0.000, 0.019 and 0.004, respectively). A significant effect of storage conditions on the number of species was also present
(P = 0.016), whereas zooplankton abundance and zooplankton diversity were not affected (P = 0.583 and 0.180). In addition, exposure time had an effect on number of zooplankton species and diversity (P = 0.001 and 0.033) but not on zooplankton abundance (P = 0.676). The traditional practice of residue burning post harvest therefore has a substantially negative effect on zooplankton
biodiversity. 相似文献