滆湖轮虫群落结构与水质生态学评价

研究了浅水湖泊--滆湖的轮虫群落结构,并用轮虫污染指示种类、E/O值、QB/T值和生物多样性指数评价滆湖的水质和营养状况.在两周年的研究中,共发现轮虫69种,污染指示轮虫39种.优势种为萼花臂尾轮虫(Brachionua calyciflorus)、前节晶囊轮虫(Asplanchna priodonta)、针簇多肢轮虫(Polyarthra trigla)、长三肢轮虫(Filinia longiseta)和裂足臂尾轮虫(B.diversicornis).轮虫密度年平均值为1584 ind./L,生物量年平均值为5.982 1 mg/L.密度秋季最高,生物量夏季较高.轮虫物种多样性较低,多样性指数与其密度及生物量正相关.滆湖三个生态功能区轮虫的种类相似;湖区北部与中部的轮虫现存量差异不显著,与南部的差异显著,中部与南部间差异极显著.根据指示生物法、生物指数法和多样性指数法评价滆湖水质及营养类型,涌湖为富营养型.     

Rotifers as indicators of lake types in Estonia

Data on the pelagic rotifer fauna in 10 Estonian lakes accumulated for 20 years, as well as published data are analysed. It is possible to distinguish three main indicator groups among rotifers: (1) for oligo- and mesotrophic lakes (Ploesoma hudsoni, Keratella serrulata, Synchaeta grandis, Asplanchna herricki, Ascomorpha ovalis, Gastropus stylifer, Conochilus hippocrepsis); (2) for meso-and eutrophic lakes (Trichocerca capucina, Filinia longiseta, F. limnetica, Keratella quadrata, K. cochlearis tecta, K.c. hispida, Polyarthra euryptera, Keratella hiemalis, Trichocerca porcellus, T. pusilla); (3) for eutrophic lakes (Brachionus spp., Anuraeopsis fissa, Pompholyx sulcata, P. complanata, Trichocerca cylindrica, Hexarthra mira).     

Peritrich epibiont protozoans in the zooplankton of a subtropical shallow aquatic ecosystem (Monjolinho Reservoir, Sao Carlos, Brazil)

Peritrich epibiont protozoans and metazooplankton (rotifers,cladocerans and copepods) were investigated seasonally in ashallow eutrophic artificial reservoir in a subtropical region(Monjolinho Reservoir, Brazil). The ciliated peritrichs Rhabdostylasp. and Scyphidia sp. were found to colonize individuals ofdifferent metazooplanktonic groups, especially copepods (47.20%of the total number of metazooplanktonic organisms found withepibionts and 57.14% of infection in the copepod population).Copepods also had the greatest epibiont load, followed by cladoceransand rotifers. Rotifers were the most important metazooplanktonicgroup (90.14% of the total) and the taxa observed with epibiontswere Filinia longiseta, Polyarthra, Brachionus and Keratella,with highest preference for the first organism. F. longisetawas present at low density compared with the others and thepreference as a substrate for epibionts may be related to itstype of adhesion surface (soft) and/or feeding habits (particlefeeding).     

Midsummer succession of rotifer plankton in a shallow eutrophic pond

Temporal changes in the density of rotifer plankton were examinedin a shallow eutrophic pond during July to September 1990, whenabiotic environmental variables were relatively stable. In earlyJuly when Daphnia similis was abundant, rotifer populationsremained at a low density. This is probably due to interferenceby the large cladoceran, because possible food was abundantand the rotifers showed high egg ratio. After late July, whenthe large cladoceran disappeared, a striking succession wasfound in the rotifer plankton. In late July, when Filinia longisetaand Conochilus dossuarius dominated, and in mid- to late Septemberwhen F.opoliensis and Brachionus falcatus dominated, there wasa causal relationship between the density and egg ratio, suggestingthat temporal changes in rotifer density were regulated mainlyby food abundance. However, in August, changes in the densityof most rotifers were not necessarily related with those inthe egg ratio. Brachionus angularis, B.forficula and Keratellaspp. decreased or remained at a low density regardless of theegg ratio, when the population of Asplanchna brightwelli wasdeveloped. However, Polyarthra vulgaris, B.calyciflorus andH.intermedia increased or maintained a high density at thistime. Stomach contents of A.brightwelli revealed that B.angularis,B.forficula and Keratella spp. were the preferred prey, whereasP.vulgaris, B.calyciflorus and H.intermedia were not. Theseresults provide strong evidence that the structure of rotiferplankton can change strikingly within a season due to species-specificdifferences not only in diet, but also in the ability to escapepredation, even if abiotic environmental variables are stable.     

A Mathematical Submodel for the Planktonic Rotatoria in the Ecosystem of the Barther Bodden (Southern Baltic Sea)

Of the rotifers inhabiting the shallow eutrophic Barther Bodden, the pelagic species feeding on fresh detritus comprising dead diatoms and green algae are of particular importance in terms of biological production. The submodel presented here refers only to this functional group (Filinia longiseta, Brachionus quadridentatus and Keratella cochlearis). The biological situation, the working hypotheses, the equation system, the measured values and coefficients used and the wiring diagram are given. The curves obtained with the model are shown in detail and tested against various criteria. Agreement between the model curves and the measured data is good.     

长江仪征－崇明段的轮虫调查

作者于１９８８年５月－１９９０年７月对长江下游仪征－崇明江段的轮虫进行了调查,发现轮虫１０３种,平均密度１５．６个／升,平均生物量０．０１３１毫克／升。各江段轮虫的种类组成及数量分布差异较大,这与长江口复杂多变的环境有关,其中盐度是造成这种差异的主要因素。     

Plankton community and the relationship with the environment in saline lakes of Onon-Torey plain,Northeastern Mongolia

The plankton community of sixteen saline lakes located on Onon-Torey plain (Northeastern Mongolia) during the filling phase and the raising of the water level was investigated in July 2011. Thirty-five taxa of phytoplankton and thirty-one species of zooplankton were found. For phytoplankton, blue-green algae (Merismopedia elegans, Anabaenopsis elenkinii, Arthrospora fusiformis, Spirulina major, Lyngbya sp., Oscillatoria sp.) and green algae (Monoraphidium minutum, Tetrastrum komarekii, Ankyra ocellata, Oocystis sp.) were dominant. For zooplankton, Filinia longiseta, Brachionus plicatilis, B. variabilis, Hexarthra mira (Rotifera), Daphnia magna, Moina brachiata, M. mongolica (Cladocera), Arctodiaptomus bacillifer, Mixodiaptomus incrassatus, Metadiaptomus asiaticus (Copepoda) dominated. Mineralization, active hydrogen ratio, dissolved oxygen and water temperature were the main factors influencing the diversity, structure and distribution of plankton organisms in the steppe lakes during low water level. The RDA analysis for phytoplankton and zooplankton from different lakes was carried out for selected two groups which included lakes and a subset related species. The first group is of oligohaline and mesohaline lakes in which mostly green algae, rotifers and copepods inhabit. The second group is of mesohaline and polyhaline lakes with mainly blue-green algae, some crustaceans and rotifers inhabiting. High abundance and biomass of Spirulina major, Oscillatoria sp. and Brachionus variabilis were observed in lakes with high mineralization, pH and temperature.     

Comparative studies on the relationship between temperature and duration of embryonic development of rotifers

The embryonic development times of four planktonic rotifers from Neusiedlersee (Austria) (Rhinoglena fertöensis, Brachionus calyciflorus, Keratella quadrata and Polyarthra dolichoptera) were determined at constant temperatures ranging from 0.6 °C to 10.5 °C. Development times decreased with increasing temperatures. The curvilinear relationship between temperature and development time was described by Bělehrádek's equation. Data on embryonic development times of rotifers are summarized and regression equations for the temperature-duration of development relationship are presented. Adaptation to temperature is discussed in the context of the thermal history of the various species and populations.     

Seasonal changes in the abundance and distribution of planktonic rotifers in Grasmere (English Lake District)

SUMMARY. The planktonic rotifers of Grasmere, a small lake in the English Lake District, were studied from August 1969 to December 1972. Twenty-four species were recorded but five were very rare. The remaining species were divided into three groups according to their seasonal occurrence: spring to autumn species ( Keratella quadrata. K. cochlearis, Gastropus stylifer, Asplauduia priodonta. Kellicottia Umgispina, Conochilus hippocrepis )., spring to early summer species ( Polyarthra dolichoptera, Synchaeta tremula, S. pectinata, S. stylata, S. oblonga, C. unicornis ), summer to autumn species ( Polyarthra vulgaris, P. major. Filinia terminalis, S. grandis, Ploesoma hudsoni, Trichocerca capucina, T. similis ). The months in which each species was abundant are given.
Keratella quadrata and Filinia terminalis were most abundant in the deepest stratum, Kellicottia longispina and Conochilus spp. were most abundant in the upper and middle strata. Trichocerca spp. showed no pronounced vertical distribution, and all the remaining species were most abundant in the upper stratum. Keratella cochlearis and Kellicottia longispina attained their highest densities over a wide range of temperature and oxygen concentration. Filinia terminalis, Conchihis spp., Asplanchna priodonta. K. quadrata , and Polyarthra spp., attained their highest densities within a narrow range of temperature and oxygen concentration. Optimum ranges are given for each species.
Major changes occurred between 1971 and 1972 when Asplanchna priodonta. Kellicottia longispina, Conochilus unicornis and Filinia terminalis increased in abundance, whilst Keratella quadrata. Gastropus stylifer, C. hippocrepis, Polyarthra spp., Synchaeta spp. and Ploesoma hudsoni decreased in abundance. These changes are discussed in relation to the temperature and oxygen requirements of each species and also to the probable enrichment of the lake after the opening of a new sewage works in June 1971.     

Rotifer vertical distributions in a meromictic basin of Lake Banyoles (Spain)

The vertical distribution of rotifer populations has been analyzed in a meromictic basin (III) of the karstic Lake Banyoles. This basin had, at the time of the study, an anaerobic monimolimnion from around 17 m in summer or 21 in winter to 25 m, its maximum depth. However, below this layer a warmer microaerophilic zone with suspended marls is found in a chimney to a depth of 130 m.The rotifer distributions of several years are compared. The presence of large populations of rotifers at the oxic-anoxic interface is constant through the years, but highly variable regarding the total abundance and relative proportions of the species, depending on the importance of the vertical mixing in winter and the posterior segregation of water layers as a function of production and decomposition processes. Filinia hofmanni, Filinia longiseta longiseta are species with a restricted occurrence at the oxycline and are not present in the other non meromictic basins of the lake. Filinia terminalis, more broadly distributed, also has dense populations in summer at the oxycline in basin III, but disappears from the plankton during this season in the other basins. Other species, such as Polyarthra dolichoptera, Anuraeopsis fissa, Keratella cochlearis and Kellicottia longispina, also showed maxima at the oxycline in summer, as well as other maxima in the metalimnion. Populations at the oxycline are probably different ecotypes adapted to low oxygen conditions, but having the advantage of high food availability.     

Relationships Between Rotifers,Phytoplankton and Bacterioplankton in the Corumbá Reservoir,Goiás State,Brazil

This study evaluates the relationships between rotifers and phytoplankton and rotifers and bacterioplankton in a tropical reservoir. Fourteen stations in the reservoir were sampled, including in its arms and tributaries, in the dry and rainy seasons. The highest rotifer density was found in the dry season, mainly in the upper and intermediary stretches of the reservoir. Brachionus calyciflorus, Polyarthra vulgaris, Keratella tropica, K. cochlearis, K. americana and Pompholyx complanata were the most abundant species. Densities of B. calyciflorus and bacteria were significantly correlated. On the other hand, there was an inverse relationship between P. vulgaris and bacteria. Diatoms (Bacillariophyceae) were observed to be associated to K. americana. We suggest that the rotifer populations play a part in microbial and herbivory food webs.     

镜湖长三肢轮虫的有性生殖

2004年5—11月,对芜湖市镜湖大、小湖区水体中长三肢轮虫(Filinia longiseta)的有性生殖及其与种群密度、水温、水体透明度、水体叶绿素a含量和轮虫总密度等环境因子间的关系进行了研究.结果表明:当水温低于22℃或水体透明度大于一定值(小湖区SD>95cm,大湖区SD>100cm)时,长三肢轮虫不进行有性生殖;而当其本身的种群密度达到一定值(小湖区种群密度>122ind·L-1,大湖区种群密度>113ind·L-1)时才进行有性生殖.长三肢轮虫的混交雌体密度仅与其本身的种群密度以及水体中轮虫总密度之间呈正相关关系(P<0·01),而与水温、叶绿素a含量、水体透明度之间均无明显的相关关系;长三肢轮虫种群的混交率和受精率与水温、水体透明度、叶绿素a含量、轮虫总密度和长三肢轮虫种群密度之间也无明显的相关性.长三肢轮虫的有性生殖发生在种群增长的早期阶段,混交雌体以间断的、多循环的方式产生;最大混交率与最大种群密度同时出现,但最大受精率出现在种群即将消失时.     

浙江两类饮用水源地浮游动物种类组成及其类群相关性分析

于2009年7月至2010年4月,在浙江省选取了10个水库和10个河网饮用水源地,进行4个季节的浮游动物采样调查。记录浮游动物101种(轮虫60,枝角类24和桡足类17种)。水库和河网轮虫的优势种分别为角突臂尾轮虫(Brachionus angularis)和针簇多肢轮虫(Polyarthratrigla),枝角类分别为颈沟基合溞(Bosminopsis deitersi)和长额象鼻溞(Bosmina longirostris),桡足类均为温剑水蚤(Thermocyclops)。水库中有一些能指示良好生态或水质的指示性种类。水库枝角类与桡足类群落之间周年在丰度和生物量上均有极显著的正相关关系(P<0.01),轮虫与桡足类类群之间的相关性最弱;河网枝角类与桡足类在夏、秋、冬季有显著的正相关性(P<0.05)。浮游动物类群之间的相关性程度,以水库的秋季与河网的夏季为最高。轮虫与浮游甲壳动物的种类丰富度随着饮用水源水体透明度的变化呈现相反的变化趋势。     

Salinity and the distribution of rotifers in the Lagos Harbour — Badagry Creek system,Nigeria

The waters of Lagos Harbour have a salinity variation of 30, as a consequence of the annual rainfall regime and of the influx of Atlantic Ocean waters. We made monthly plankton hauls at 10 stations for 11 months starting in October 1986, and found 51 species of rotifers, with Brachionus baylyi Sudzuki & Timms, Keratella hispida Lauterborn, Colurella obtusa Gosse, and Filinia pejleri Hutchinson recorded for the first time in Nigeria. In distribution, species numbers decreased with increasing salinity. Brachionus plicatilis, B. rubens, Hexarthra intermedia, Keratella americana, K. cochlearis and K. tropica were classed as euryhaline. Stenohaline species were Anuraeopsis fissa, Ascomorpha ovalis, Filinia longiseta, F. opoliensis, Gastropus sp., Lecane curvicornis and Monostyla stenroosi. All other monogononts were restricted to waters of salinity below 1.     

芜湖市镜湖轮虫群落结构分析及水质的生态学评价

2003年1—12月,对芜湖市镜湖轮虫群落结构的周年动态进行了研究,并分析了轮虫密度与有关生态因子间的关系。经鉴定,共发现轮虫55种,隶属于15科21属。密度优势种为裂痕龟纹轮虫(Anuraeopsis fissa)、暗小异尾轮虫(Trichocerca pusilla)、前额犀轮虫(Rhinoglena frontalis)、红多肢轮虫(Polyarthra remata)、长三肢轮虫(Filinia longise-ta)、广布多肢轮虫(Polyarthra vulgaris)和多须伪前翼轮虫(Proalides tentaculates),而生物量优势种为前节晶囊轮虫(Asplanchna priodonta)、多须伪前翼轮虫和暗小异尾轮虫。全年轮虫的总密度与水温、叶绿素a浓度及小型纤毛虫密度具有显著的相关性;温度对全年轮虫总密度的影响最大,叶绿素a浓度对春、冬季轮虫总密度影响最大,小型纤毛虫密度对夏季轮虫总密度影响最大,而水温是影响秋季轮虫总密度的主要因素。根据污染指示生物、物种多样性指数和Q值并结合水理化性质对治理后的镜湖水质所进行的初步评价表明,经清淤、截流和换水等措施治理后,小湖区应偏属寡污-β中污至β中污型水体,大湖区属于β中污型水体;目前镜湖水体处于中营养后期—富营养化初期阶段。       

Temporal and vertical distribution of planktonic rotifers in a meromictic crater lake,Lake Nyahirya (Western Uganda)

Quantitative zooplankton sampling was carried out biweekly during 16 months in Lake Nyahirya, a Western Uganda crater lake. Six out of 24 rotifer species recorded from the lake were quantitatively important (Horaella brehmi, Brachionus angularis, B. caudatus, Keratella tropica, Filinia longiseta and F. opoliensis, and three others were common (Brachionus falcatus, Asplanchna sieboldi and Conochiloides natans). Rotifer peaks were correlated with rainy periods and relatively clear water, which coincide with the European spring and autumn. All species were able to deal with hypoxic conditions. A clear niche separation can be observed between different genera and between species of the same genus. The population dynamics of the rotifers seem to be ruled by repeated irregular environmental fluctuations. Rainfall appears to be a primary steering factor.     

Temporal and Spatial Distributions of Rotifers in Xiangxi Bay of the Three Gorges Reservoir,China

From July 2003 to June 2005, investigations of rotifer temporal and spatial distributions were car‐ried out in a bay of the Three Gorges Reservoir, Xiangxi Bay, which is the downstream segment of the Xiangxi River and the nearest bay to the Three Gorges Reservoir dam in Hubei Province, China. Thirteen sampling sites were selected. The results revealed a high species diversity, with 76 species, and 14 dominant species; i.e., Polyarthra vulgaris, Keratella cochlearis, Keratella valga, Synchaeta tremula, Synchaeta stylata, Trichocerca lophoessa, Trichocerca pusilla, Brachionus angularis, Brachionus calyciflorus, Brachionus forficula forficula, Ascomorpha ovalis, Conochilus unicornis, Ploesoma truncatum and Anuraeopsis fissa. After the first year of the reservoir impoundment, the rotifer community was dominated by ten species; one year later it was dominated by eight species. The community in 2003/2004 was dissimilar to that in 2004/2005, which resulted from the succes‐sion of the dominant species. The rotifer community exhibited a patchy distribution, with significant heterogeneity observed along the longitudinal axis. All rotifer communities could be divided into three groups, corresponding to the riverine, the transition and the lacustrine zone, respectively. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Ecology of rotifers of Surinsar,a subtropical,fresh water lake in Jamme (J & K), India

17 species of rotifers have been recorded from Lake Surinsar, Jammu (J & K), India of which some are either exclusively limnetic (Brachionus angularis, Hexarthra sp., Filinia opliensis), or littoral (Brachionus patulus, M. ventralis, Trichotoria sp., Platyias quadricornis, Lecane (Monostyla) decipiens, L (M), bulla and Lecane sp.) and others (Keratella tropica, Anuraeopsis fissa, Brachionus quadridentatus, B. calyciflorus, Trichocera sp., T. similis, and Polyarthra sp.) seem to be wandering species. Seasonal maxima for both littoral and limnetic zones are reported. Most population maxima are contributed mainly by one or at best two species.Physico-chemical factors like temperature, pH, dissolved oxygen, free carbon dioxide, calcium, magnesium, and total alkalinity have been studied and their infuence on these rotifer species are discussed. On their thermal responses, the available rotifer species have been classified as warm stenothermal, cold stenothermal or eurythermal. The importance of Mytilina ventralis as a biological indicator for dissolved oxygen in this lake has been pointed out.     

Zooplankton of a swamp water ecosystem

The Great Dismal Swamp, located in southeastern Virginia and extending into northeastern North Carolina, is a unique ecosystem which has undergone severe alteration over the last 200 years due to agricultural, municipal and timbering development. The swamp is presently about 50% of its late 1700 size when George Washington commissioned the construction of the first of a series of drainage ditches that have subsequently reduced the swamp aquatic environs to a ditch network draining into Lake Drummond located near the swamp's center. The swamp waters are characterized by a brown color, high suspended organic matter, high acidity and low nutrient levels. This paper presents the first comprehensive study of the zooplankton assemblages of the Great Dismal Swamp.Zooplankton was collected for one year at 14 stations and was dominated by rotifers. Of the 84 species identified, 61 were rotifers, 18 were Cladocera and 5 were copepods. Many of the species collected were cosmopolitan and acid tolerant forms. Dominant lake rotifers included Polyarthra vulgaris, Conochiloides dossuarius, Keratella cochlearis, Trichocerca similis, Synchaeta longipes and Microcodon clavus. Dominant crustaceae included Bosmina longirostris, Diaphanosoma leuchtenbergianum, Mesocyclops edax, and Tropocyclops prasinus.Usually the ditch zooplankton was the same as that of the lake. Of the seven ditches studied, the most unique chemically and biologically were Interior, Washington, and Portsmouth. Measurable alkalinity was detected in Interior and Washington Ditches. Alkaline water rotifers such as Brachionus, Mytilina, Filinia, Notholca Platyias and Keratella earlinae were found in these ditches. The rotifer, Keratella valga, was only found from Portsmouth Ditch, during a period when water was flowing into the lake and it contained high nutrient levels.Research funded in part by the Virginia Academy of Sciences and the Center for Environmental Studies, Virginia Polytechnic Institute and State University.     

The essential omega-3 fatty acid EPA affects expression of genes involved in the metabolism of omega-6-derived eicosanoids in Daphnia magna

We quantified the predation of Acanthocyclops americanus from the shallow Mediterranean lake Albufera, using gut contents from field collections and laboratory feeding tests. For functional response studies, we used Brachionus plicatilis (at 6 concentrations, 400–4000 ind. 40 ml⁻¹) and Diaphanosoma mongolianum (at 2–20 ind. 40 ml⁻¹). Copepod feeding rates were also estimated using different proportions of rotifer prey and lake seston (0–67.5% of seston + 40 individuals of B. plicatilis). Prey selection studies were conducted using five zooplankton species: Brachionus angularis, Brachionus plicatilis, Keratella tropica, Daphnia magna and Diaphanosoma mongolianum. Gut contents of field-collected adult Acanthocyclops contained filamentous algae and cyanobacteria and 16 zooplankton species (Keratella cochlearis, unspined and spined forms, K. tropica, Brachionus plicatilis, Brachionus calyciflorus, Brachionus angularis, Brachionus variabilis, Asplanchna girodi, Polyarthra vulgaris, Synchaeta pectinata, Lepadella rhomboides, unidentified bdelloids, Alona rectangula, Chydorus sphaericus, Bosmina longirostris, D. magna, Ceriodaphnia dubia and copepod nauplii). When fed B. plicatilis or D. mongolianum, female A. americanus had higher prey consumption rates than males. Increased proportion of lake seston caused reduced consumption of brachionid prey. Our data suggest that A. americanus is omnivorous in nature.