飞来峡水库蓄水初期营养状态及浮游生物分布特征

于2000年丰水期和枯水期调查分析了新建河流型水库-飞来峡水库在蓄水初期的营养状态及浮游生物特征。结果表明:水库处于营养累积高峰期,已开始回落,但流域上游大量含磷废水使水库中磷含量继续上升,目前属于中营养型。共记录到浮游植物29种(属),以蓝藻门、绿藻门、硅藻门种类较多,其中丰水期以蓝藻和绿藻为主,枯水期是硅藻占优势,除大坝附近外,浮游植物两个季节密度变化不大,为0.39×10⁶cells·L^-1.浮游动物53种(属),其中包括僧帽溞和透明薄皮溞两种嗜寒性种类,丰度为52ind.·L^-1,枯水期高于丰水期,数量以轮虫和无节幼体为多。     

广东省大中型供水水库营养现状及浮游生物的响应

于2000年调查了广东省18座大中型供水水库的水质现状并探讨了浮游生物对营养水平的响应。总氮、总磷、透明度和叶绿素a分别为0．15～7.15mg／L、0．003～0．387mg／L、0．4～6．3m和0．6～32．3ug／L。总氮、总磷、透明度均与叶绿素a呈较高的相关性。根据这4个因子的综合加权营养状态指数为23．7～55．1,季节差异不大,大多数水库处于中营养状态。金藻在中-富及富营养型水库中没有分布,而蓝藻、绿藻、硅藻和甲藻在调查水库中均有比较广的营养生态位,但它们的密度及相对优势度在各营养型水库中有一定的差异。高营养水平水库有较高的细胞密度和叶绿素a含量。营养水平较低的水库浮游植物以硅藻-甲藻、硅藻-绿藻或金藻-硅藻为主;营养水平较高的水库以蓝藻-硅藻或蓝藻-绿藻为主,并有较高的裸藻密度。浮游动物基本上以桡足类为优势种群,但在中-富营养和富营养型水库中,哲水蚤种类比低营养型水库中少。枝角类优势种类在各营养型水库差别不大。轮虫对水体营养水平的响应相对比较显著。低营养水平水库的轮虫以广营养型、中营养型或寡中营养型种类为主,种类数目比较少;富营养和中-富营养型水库的轮虫以喜在中营养到富营养条件下生长的种类为主,且轮虫种类数目比较多。     

污染水体浮游生物的调查

水体是指存在于自然界的水与其所含的悬浮物、底泥及水生生物等物质的总合,随着工业开发、农业生产和城市建设的发展,自然环境中的水污染已成为全社会关注的问题。结合当前国内外中学科技活动的动态,选择污水浮游生物调查作为课外活动的项目,具有联系实际、内容丰富、周期较短及实效可行的特点。1　工作原理引起自然水体污染的原因很多,包括工业废水、农业化肥与农药、生活污水以及大气污染物沉降等因素。其中,工业废水中的有毒物质会使多数或全部水生生物死亡。生活污水及农业污染常使水体人为富营养化;由于过多的有机质和无机盐进入水体后…     

亚热带大型水库—新丰江水库的浮游生物群落特征

于2000年丰水期和枯水期,调查了新丰江水库的浮游生物群落结构。新丰江水库处于贫营养状态,浮游生物密度和生物量均较低。浮游植物34种,丰水期以蓝、绿藻为主,分别占总数量的31.7%和26.8%,蓝藻、绿藻细胞微小,chl-a量未占优势;枯水期硅藻为优势种群,占63.9%。浮游动物22种,丰水期轮虫为主,占65.3%,枯水期桡足类占81%,丰水期动物密度较高,但丰水期以轮虫如螺形龟甲轮虫为主,枯水期以无节幼体、桡足幼体及广布中剑水蚤居多,因此枯水期生物量高于丰水期。     

鹤地水库浮游生物与富营养化特征分析*

于2000年丰水期和枯水期调查分析了鹤地水库的营养状态及浮游生物特征。结果表明:鹤地水库营养盐含量很高,综合营养状态指数评价为中一富营养化水平。浮游植物丰水期和枯水期的细胞密度分别为1950.5～3509.7×10⁴cells·L^-1和130.5～231.3×10⁴cells·L^-1,蓝藻中的微囊藻和席藻数量占细胞总数的83%以上。在丰水期和枯水期,浮游植物的群落结构均为蓝藻-绿藻-硅藻型,优势种为微囊藻和席藻。次优势种由丰水期蓝藻中的粘球藻,颤藻,绿藻中的衣藻,和硅藻中的颗粒直链藻等转变为枯水期的蓝藻门的水华束丝藻和硅藻门的颗粒直链藻等富营养化指示种。鹤地水库的浮游动物种类不多,但数量很高。丰水期的无节幼体和桡足幼体数量很多,但从优势种类来说,轮虫以曲腿龟甲轮虫,纵长异尾轮虫,剪形臂尾轮虫为主,枝角类的优势种为长额象鼻蚤;枯水期时无节幼体的数量最多,桡足幼体数量急剧下降,优势种类则转变为枝角类的长额象鼻蚤和桡足类的广布中剑水蚤。两个水期浮游动物的优势种类均是以耐污种和广布性种类为主。     

广东沿海与粤北山区中小型水库浮游生物群落比较分析

于丰水期和枯水期对广东山区水库(赤石迳水库)、沿海水库(大水桥、赤沙水库)三个水库的湖泊区和河流区进行研究,分析水质和浮游生物群落结构。三个水库之间的浮游生物群落均有所区别,地理位置和地形不同而引起的温度差异以及外源性营养盐输入是造成浮游生物种类和数量差异的主要原因。沿海水库不分层,而山区水库丰水期温跃层明显。各水库的氮磷比均较高,chl.a水平主要受磷限制,沿海水库则多喜暖性的种类,如裸藻、隐藻、沙居剑水蚤等,山区水库发现较多喜冷性浮游生物,如金藻、透明溞等,丰水期的甲藻丰度也相对高于枯水期。     

放养鲢鱼(Hypophthalmichys molitrix C et V)对水库围隔浮游生物群落的影响

本文研究在水库围隔实验生态系统中鲢鱼对浮游生物群落的影响。结果表明,放养鲢鱼后,浮游动物生物量、浮游植物生物量、叶绿素a和浮游植物毛产量分别下降了58.7％、63.6％、52.5％和65.0％;透明度、浮游植物群落多样性指数分别提高了18.2％、32.5％;铜绿微囊藻数量减少了90.6％“水华”得到明显抑制。但小型绿藻(<20μm)数量未出现显著变化,因而其在藻类生物量中所占比例反而提高了82.3％。围隔内可被鲢鱼滤食的大型藻类(硅藻、甲藻、隐藻和绿藻(>20μm))占藻类生物量的85.8％,因此鲢鱼的存在能明显限制浮游植物的生物量。此外,放养鲢鱼还显著降低了水体中的COD,TP,DO和pH值,这表明鲢鱼对水质有净化作用。     

广东长潭水库浮游生物群落结构特征

长潭水库是广东梅州市重要的备用水源地,属于国家一类水源保护区。2010年7月,通过分析长潭水库浮游生物群落组成、生物量及多样性指数等群落结构特征和水体理化指标,揭示长潭水库富营养化水平。结果显示,长潭水库鉴定出55种浮游植物,隶属于6个门,优势种为绿藻门的栅藻（Scenedesmus sp.）、蓝藻门的微囊藻（Microcystis sp.）和伪鱼腥藻（Pseudanabaena sp.）、隐藻门的隐藻（Cryptophyta sp.）以及硅藻门的小环藻（Cyclotella sp.）和针杆藻（Synedra sp.）;藻类密度范围1.71×10⁶~2.44×10⁸ cells/L;浮游动物共检出44种,包括轮虫、枝角类和桡足类,其中轮虫是主要类群。综合营养状态指数评价结果显示,长潭水库部分水体呈轻度富营养化。典范对应分析结果显示,浮游动物、溶解氧、总氮、总磷和化学需氧量是影响长潭水库浮游植物群落结构的关键环境因子。     

广东典型小型供水水——-契爷石水库浮游生物与富营养化特征分析

于2000年丰、枯水期对契爷石水库的理化因子,浮游生物种类组成,细胞密度等进行了调查研究,并利用有关评价指数对该水库水体的营养水平进行了评价。结果表明,契爷石水库目前已进入富营养化状态,且枯水期较丰水期富营养化程度更为严重,另外,全年有机污染也比较严重。浮游植物丰水期以蓝藻、绿藻为主,枯水期以蓝藻、硅藻为主,该水库属于典型的蓝藻-绿藻-硅藻型水库,且有较高丰度的耐有机污染的裸藻所在。浮游动物以轮虫和桡足类为主,轮虫主要以耐有机、喜富营养的萼花臂尾轮虫（Rrachionus calyciflorus）、前节晶囊轮虫（Asplanchna priodonta）、螺形龟甲轮虫（Keratella cochearis）为主,挠足类主要以无节幼体,桡足幼体为主,成体很少,且主要以剑水蚤为主,喜寡营养的哲水蚤在该水库中没有出现,枝角类种类,数量都很少,多为广温型、嗜暖型种类,其中长额象鼻蚤（Bosmina longirostris）和微型裸腹蚤（Moina micrura）习居于富营养型水体中。     

密云水库的浮游生物群落

2002年4～10月对密云水库浮游生物群落的调查结果显示：浮游植物有6门,58属,122种,细胞密度为565．30～10^4cells／L,4月份硅藻(Bacillariophyta)占优势,6～10月蓝藻(Cyanophyta)占绝对优势．浮游植物优势种群有水华微囊藻(Microcystis flas-aquae)、颗粒直链藻(Melosira granulata)、梅尼小环藻(Cyclotella meneghiniana)、角甲藻(Ceratium hirundinella)等。浮游动物有36种,密度为4761ind/L;浮游动物具有原生动物在数量上占绝对优势．轮虫次之,枝角类与桡足类数量较少的特点。浮游动物的优势种群有弹跳虫(Halteria grandinella)、急游虫(Stromlridium uiHde)、针簇多肢轮虫(Polyarthra trigla)、螺形龟甲轮虫(Keratella cochlearis)、广布中剑水蚤(Mesocyclops leuckarti)、长额象鼻蚤(Bosmlna longirostris)等．与1980年监测结果相比,密云水库浮游生物总密度上升较快,群落结构和优势种群也发生了明显变化．浮游生物优势种群的指示作用显示,在植物生长季节,库区水体已进入富营养状态。     

Plankton richness in a eutrophic reservoir (Barra Bonita Reservoir,SP, Brazil)

Species richness of plankton was studied in a eutrophic reservoir (Barra Bonita Reservoir) of the Middle Tietê River, São Paulo State, Brazil, during the period 1985–1986. This reservoir is formed by two rivers: the Tietê and the Piracicaba (the main tributaries), of which the Tiête is more eutrophic, having conductivity and nutrient concentration values twice those of the Piracicaba. In addition, the reservoir is fed by 114 smaller tributaries. Monthly sampling was carried out at three stations representing different environmental conditions: St1 on the Tietê, S2 on the Piracicaba, and St3 at the confluence of the two rivers. For the phytoplankton community, the Piracicaba River (St2) proved the richest site, with a listed 72 species with abundance of Chlorophyta, while St1 and St3 registered 59 and 50 species, respectively, with abundance of Cyanophyta. For the zooplankton community a great difference was not registered in species number at the three stations but the species composition and dominant species of rotifers and copepods were quite different. The occurrence of Mesocyclops meridianus and Metacyclops mendocinus, specific for St2;Mesocyclops ogunnus and Notodiaptomus iheringi, specific for St1, and that of these two species plus Mesocyclops meridianusat St3 shows that the conditions combining at this station were favorable to Mesocyclops meridianus but not to Metacyclops mendocinus. Both for phytoplankton and zooplankton, high values found of species richness were compared to species richness of natural lakes, e.g., Dom Helvecio, a monomictic stable lake in eastern Brazil, and another fifteen lakes in the same region.In conclusion, this work shows that environmental gradients are strong selective factors that enhance plankton richness in eutrophic reservoirs exhibiting environmental instability. This fact could explain the presence of a high number of plankton species associated with a high number of individuals in Barra Bonita Reservoir, supporting the effects of the intermediate disturbance hypothesis.     

用于海洋原位浮游生物探测的同轴数字全息显微技术研究

本文将数字全息与显微成像技术相结合,设计搭建了一套数字全息显微系统,用于对浮游生物进行光场获取。基于该系统获取的光场信息,通过在不同景深对图像进行再现,既可以获到单一浮游生物的清晰图像,也可以获得一定水体内浮游生物微粒在海水中的三维分布情况。通过实验测得系统分辨率可以达到7．8微米,景深可以达到10毫米,优于一般光学显微镜的技术指标。研究结果表明优势明显的数字全息显微系统是一种适合海洋原位探测的浮游生物研究的有效方法。基于数字同轴显微系统的水下仪器开发将是下一步工作的努力方向。     

珠海地区小型抽水型与非抽水型水库的浮游植物群落结构变化

2006年4月、8月、12月对珠海3座抽水型水库和3座非抽水型水库的水质和浮游植物进行采样和测定.抽水型水库和非抽水型水库的浮游植物分别有67种和56种.蓝藻门的假鱼腥藻(Pseudanabaena sp.)、湖丝藻(Limnothrix redekei)和拟柱孢藻(Cylindrospermopsis rackiborskii)仅在抽水型水库中检到,而绿藻门的鼓藻(Cosmarium sp.)仅在非抽水型水库中检到.抽水型水库浮游植物种类的季节变化比非抽水型水库明显,且浮游植物的丰度和生物量均高于非抽水型水库.抽水型水库浮游植物丰度在1.25×105～4.38×106cells L-1之间,以蓝藻和小型绿藻为主;非抽水型水库浮游植物丰度在7.1×104～4.61×106cells L-1之间,以绿藻门的鼓藻为主.抽水型水库浮游植物的生物量在2.3～8.8 mgL-1之间,非抽水型水库浮游植物的生物量在1.3～5.6 mgL-1之间.抽水型水库浮游植物的生物量在冬春季高于夏季,而非抽水型水库浮游植物的生物量动态相反.抽水型水库浮游植物的优势种具有明显的季节变化.非抽水型水库浮游植物具有相对稳定的群落季节变化,其优势种的组成较为稳定.对于抽水型水库而言,咸潮前期集中调水入库,不仅改变了水库的营养盐负荷,也改变了水库水动力学的季节动态,这也是导致抽水型与非抽水型水库在浮游植物群落结构与动态上存在明显差别的关键因素.     

Vertiquant: A Device for Automatically Recording Vertical Migration of Plankton

Vertical migration is a key subject in understanding zooplankton ecology and its influence on aquatic ecosystems. This paper introduces a device for automatically recording vertical plankton migrations to study proximate factors regulating the stimulus, timing and amplitude of these movements under controlled laboratory conditions. The instrument records the light scattered by organisms at their respective depths and processes the signals in real time to a graphic representation of the organisms vertical distribution. Organisms of different taxa from a size of <40 μ, to > 10 000 μm were used for these experiments. Daphnia migrations in response to UV light are used to demonstrate the basic functions of the instrument.     

Plankton response to weakening of the Iberian coastal upwelling

Coastal upwelling regions, which are affected by equatorward‐wind variability, are among the most productive areas of the oceans. It has been suggested that global warming will lead to a general strengthening of coastal upwelling, with important ecological implications and an impact on fisheries. However, in the case of the Iberian upwelling, the long‐term analysis of climatological variables described here reveals a weakening in coastal upwelling. This is linked to a decrease of zonal sea level pressure gradient, and correlated with an observed increase of sea surface temperature and North Atlantic Oscillation. Weakening of coastal upwelling has led to quantifiable modifications of the ecosystem. In outer shelf waters a drop in new production over the last 40 years is likely related to the reduction of sardine landings at local harbors. On the other hand, in inner shelf and Ria waters, the observed weakening of upwelling has slowed down the residual circulation that introduces nutrients to the euphotic layer, and has increased the stability of the water column. The drop in nutrient levels has been compensated by an increase of organic matter remineralization. The phytoplankton community has responded to those environmental trends with an increase in the percentage of dinoflagellates and Pseudonitzschia spp. and a reduction in total diatoms. The former favors the proliferation of harmful algal blooms and reduces the permitted harvesting period for the mussel aquaculture industry. The demise of the sardine fishery and the potential threat to the mussel culture could have serious socio‐economic consequences for the region.     

Plankton Succession in the Temporary Lake Koronia after Intermittent Dry‐Out

This study examines the plankton succession in a polluted temporary lake after intermittent dry‐out. The initial stage after flooding was heterotrophic (zooplankton/phytoplankton carbon biomass ratio > 1). Phytoplankton species richness increased exponentially within a few months after inundation. The chlorophyte Koliella cf. longiseta was the pioneer colonist which was replaced by Oocystis sp. reaching 300 340 ind mL^–1. The initial conditions favored rotifer and cladoceran colonists, not previously recorded, to successfully establish populations. The species that finally became dominant hatched from the lake's sedimentary egg bank with Daphnia magna being prominent. Nevertheless, the zooplankton community was unable to control the high biomass of chlorophytes (zooplankton/phytoplankton carbon biomass ratio < 0.4). Plankton succession in this temporary lake was mostly determined by the past phytoplankton – zooplankton species pool rather than by the established new colonists. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Analysis of Plankton Dynamics in a Southwestern U.S.A. Reservoir Using ATP Assays

Plankton biomass in size segregated (i.e. 0.45–10 μm, 10–64 μm, 64–165 μm, and > 165 μm) samples was measured using ATP assays for two years in H. H. Moss Reservoir. The presence of variable numbers of microcrustacean zooplankton in the > 165 μ size class introduced significant, and perhaps inaccurate, variance into temporal dynamics of total ATP concentrations. As many as six physiochemical parameters, measured during 1975–76, were required to produce a significant multiple regression against ATP concentrations; a significant correlation between total ATP measured in the photic zone and surface temperature was observed. A large standing crop of nannoplankton (i.e. 0.45–10 μm) existed in the anaerobic and aphotic hypolimnion during summer stratification both years. This suggested that microbial heterotrophy was an especially important primary trophic event in the reservoir. Particulate (POC) and dissolved (DOC) organic carbon were measured in 1976–77. Organic carbon (POC + DOC) regressed significantly against ATP concentration in the 0.45–10 μm size class and microbial biomass (i.e. 0.45–165 μm) averaged 32 per cent of POC. When biomass was monitored over 24-hour periods in the photic zone, significant changes were documented in various size classes, especially nannoplankton; but total microbial biomass remained relatively constant.     

Plankton and primary productivity of Lake Manzala,Egypt

Primary production and distribution and abundance of phyto- and zooplankton of lake Manzala were investigated from June 1985 to June 1986.Primary production varied from 4.1 to 28.7 g O₂ m^–2 d^–1 with the highest values 24.2 and 28.7 g O₂ m^–2 d^–1 recorded in the eastern and southern sectors and the lowest value 4.1 g O₂ m^–2 d^–1 recorded in the northern sector. The seasonal mean production for the lake was estimated at 13.3 g O₂ m^–2 d^–1.Mean phytoplankton abundance ranged from 32.7 10⁷ to 76.1 10⁷ cells m^–3 with a mean value of 48.10⁷ cells m^–3. Diatoms were the dominant phytoplankton group comprising 52 to 90 % by number. The greatest relative abundance (87 to 90%) was recorded in the southern sector.Mean zooplankton abundance ranged from 30.1 10³ to 44.4 10³ organisms m^–3 in the eastern sector to 5.5.10³ in the northern sector. In response of eutrophication, the species composition changed significantly over the last 20 years. Cladocerans represented less than 1% of zooplankton during 1959/60, but 75% in 1985/86. Rotifers constituted 40% in 1959/60, and only 1% in 1985/86. Cirriped larvae declined from 21% to 1%.