远海梭子蟹幼体饵料初步研究

分别选用轮虫、轮虫 卤虫、轮虫 卤虫 扁藻、卤虫、扁藻为饵料 ,将刚孵化的远海梭子蟹氵蚤状幼体培育至幼蟹第二期。结果发现 :轮虫 卤虫 扁藻的效果最好 ,幼蟹第二期的成活率为 15% ,轮虫 卤虫的成活率为 11% ,卤虫的成活率为 10 %。而轮虫组仅能培育至 氵蚤状幼体第三期 ,没有氵蚤状幼体第四期幼体出现 ;扁藻最差 ,仅能培育至氵蚤状幼体第一期 ,没有氵蚤状幼体第二期个体出现。同时发现 ,轮虫 卤虫组与卤虫组培育时间均比轮虫卤虫 扁藻组长 ;各期幼体的阶段成活率比较而言 ,氵蚤状幼体第一期最高 ,而氵蚤状幼体幼体第五期最低     

环境因子对L型、S型褶皱臂尾轮虫生长的影响

在实验室条件下,通过种群累积培养的方法,研究了不同盐度和小球藻(Chorellavulgaris)、亚心形扁藻(Platymonassubcordiformis)、微绿球藻(Nannochlorisoculata)、波吉卵囊藻(Oocystisborgei)等不同饵料微藻对L型褶皱臂尾轮虫(BrachionusPlicatilistipicus)和S型褶皱臂尾轮虫(BrachionusPlicatilisrotundiformis)生长的影响,探讨这两种轮虫在生态条件上的差异。结果表明:L型和S型褶皱臂尾轮虫对盐度的适应有显著的差异,生长的最适盐度分别为15和20,大水体培养时,其适宜生长的盐度范围分别是15~20和10 ~30。饵料微藻对L型和S型褶皱臂尾轮虫生长的影响一致。小球藻培养效果在4种饵料微藻中最好,其生长率明显高于微绿球藻和亚心形扁藻,波吉卵囊藻培养效果较差。     

南海海域三疣梭子蟹的幼体培育

幼体期Z1和Z2投喂扁藻和轮虫,Z2后期开始以轮虫和卤虫无节幼体混合投喂,Z3后用卤虫无节幼体投喂,大眼幼体用不同饵料培育,进行南海海域三疣梭子蟹幼体培育,结果表明:溞状幼体平均成活率为15.3%;Z2变态为Z3、Z4变态为M为溞状幼体培育的敏感期,幼体的阶段成活率较低;以卤虫无节幼体、冰冻卤虫成虫、活卤虫成虫为饵料,均能使培育大眼幼体至幼蟹,其中活卤虫成虫投喂、加防残网片培育效果最好,成活率达80%。     

COPPER ACCUMULATION AND TRANSPORT IN A MARINE FOOD CHAIN COMPOSED OF PLATYMONAS SUBCORDIFORMIS, BRACHIONUS PLICATILIS AND PENAEUS MONODON

mooimON~ofheaVyInetalpollutantsonmarineorganismswereextenSivelystudedguiAgenetal.,l99l,LiuFayietal.,l988,PatinS.A.,l982).bouseofthemarineansySteIncomPlexityandthevarietyofthefoodchain,pollutantSaretIanspondindiliferentwayS-Therefore,studyofthetIansPortofPonutantsinthefoodchainhasdrawnmuchattention.TherearerePortSontheaCCUInulatinnandusnsportofsorneradi0nuclidesguiFulongetal.,l984)suchasCs,Co,andZnandsometIaceelernentSsuchasV,SeandNinthernarinefoodchain(Mthemand,Ctal.,l98O;Unsal,…     

食物类型和浓度对双齿许水蚤摄食的影响

在不同饵料条件下,对双齿许水蚤(Schmackeria dubin)的清滤率(mL.只-1.h-1)、滤食率(细胞.只-1.h-1)和摄食率(mg.只-1.h-1)进行了测定。结果表明:以湛江等鞭金藻(Isochrysis zhanjiangensis)为饵料,其浓度为15×104～120×104 mL-1时,双齿许水蚤的摄食率达到较大;分别饲以同生物量的牟氏角毛藻(Chaetoceros müelleri)、亚心形扁藻(Platymonas subcordiformis)、湛江等鞭金藻、小球藻(Chlorella sp.)时,饵料为角毛藻和扁藻时双齿许水蚤的摄食率达到较大;饲以同生物量的牟氏角毛藻、亚心形扁藻、湛江等鞭金藻、小球藻、颤藻(Oscillatoria sp.)、小环藻(Cyclotella sp.)六种藻的混合饵料时,双齿许水蚤对湛江等鞭金藻的摄食率和选食率均为最大,分别为0.0458 mg.只-1.h-1和17.1%。可见,饵料浓度、饵料种类、混合饵料对双齿许水蚤的清滤率和摄食率均有显著影响(P<0.05)。     

珠母贝、亲贝人工促熟培育与催产的研究

从23 ~24℃开始,每4~5d升高水温1℃,终至26~27℃,并用亚心形扁藻(Platymonassubcordiformis)、三角褐指藻(Phaeodactylartriconrutum)及辅助饲料投喂培育,促进珠母贝[Pinctadamargaritifera(Linne) ]亲贝性腺发育成熟。用阴干刺激、异性产物刺激及浓扁藻液结合诱导,催产率达100%。     

Copper accumulation and transport in a marine food chain composed ofPlatymonas subcordiformis, brachionus plicatilis andPenaeus monodon

Accumulation, transport and toxicity of Cu in the food chain consisting ofPlatymonas subcordiformis, Brachionus plicatilis andPenaeus monodon were studied. Effects of Cu on the growth of organisms in the food chain were investigated and the inhibiting effect concentration (EC₅₀) of Cu was then determined according to the dynamics of the relative number of cells or total individuals of organisms, expressed in percentages with reference to the controlled system, under different culture conditions. On the basis of the variations in accumulation and percentages of accumulation of Cu in the biological phase, the relationship between the accumulation of Cu in organisms and its toxicity was analyzed and the main approach for determining the transport of Cu in the food chain was then discussed. Project 3880644 supported by NSFC.     

Effects of strontium-induced stress on marine microalgae Platymonas subcordiformis （Chlorophyta： Volvocales）

1 INTRODUCTION Heavy metal pollution in marine environment has always been a serious problem over the last several decades, because most of the heavy metal species that enter marine environment accumulated there without decomposition. Strontium is a minor…     

引进印度尼西亚大珠母贝人工育苗试验

在雷州半岛海域水温24.0～30.0℃、盐度30.8～32.5、pH8.0～8.3条件下,以牟氏角毛藻,亚心形扁藻,牟氏角毛藻、亚心形扁藻和小球藻,天然混合藻等4种饵料,进行印度尼西亚产大珠母贝亲贝促熟培育试验。结果表明:不同饵料组合在亲贝促熟百分率、排精产卵率和受精率之间差异不显著(P>0.05);阴干温差流水刺激可以有效诱导亲贝排精产卵,优选幼虫和投放合适的采苗器可以提高幼虫的变态率。     

4种中草药对亚心形扁藻生长的影响

于1998年3月至5月运用单种培养的方法研究了马齿苋、桔梗、木瓜和花粉等四种中草药浸提液对亚心形扁藻生长的影响。结果表明：在培养液中添加不同浓度的马齿苋、桔梗和花粉浸提液的各处理组均对亚心形扁藻有一定的促进作用。其中马齿苋、桔梗效果最好,花粉次之。最佳浓度分别是1．50％,0．75％和1．00％浸提液。其相对生长常数（K）分别是对照组的1．41倍、1．41倍和1．21倍。而木瓜浸提液添加量过高和低对亚心形扁藻有一定的抑制作用。可见,在亚心形扁藻培养液中添加一定量的马齿苋、桔梗浸提液是可行的。     

BIOCONCENTRATION OF TETRACHLOROBENZENE IN MARINE ALGAE

INTRODUCTIONChlrinatal~arewidelyedinindusnyandhouseholds,andsoisofsboi-ficantenviID~lcom,hauseitisoftenndaswaste.contributingtothepoilutantsinalltyPesofwater(Afghanetal.,l979).AlthoughsornedataontoxidtyandbioconnitionofchiorinatalboinaquaticorganismSwerepublishedopbasetal.,l987,LohnerCtal.,l987,Maunot,l987,Kuhnctal.,l99O),thebioCOntritionpotritinlparade,indudingk,,k,andBCF,werenotdetenninWelldriusethernehodsford~ngtheparaIneterswereleSsthanaccurate(Wangetal.,l996).Thepresentstudyab…     

TOXICITY OF CHLORINATED BENZENES TO MARINE ALGAE

Towhomcorrespondenceshouldbeaddressed.ImODUcr0NMarinealgaearethemosttwortantprimaryproducersandplayanimPortantroleindetenniningthefateofpersistenthydrophobicorganicchdricaIs(HOCs)inthernarineeresySteIn.TheirhydrophobicnatureresultsinanenhanedassociationwithH0Csintheanwatercolurnn(Swackhameretal.,l993).HOCfateisdowhnatalbytwoproanes,verti-caltransporttobottomsedimentSbydeadCellsandtIansportintothefood-webbyrooplanktongraring.TherelativetoortanceofthetwoproassesdependsonprharyproduCtion…     

Comparative Studies on Phosphorus Uptake and Growth Kinetics of the Microalga Tetraselmis subcordiformis and the Macroalga Ulva pertusa

Short-term uptake experiments and long-term semicontinuous culture experiments were performed under the condition of phosphorus (P) limitation to estimate and compare the P uptake and growth kinetics of the microalga Tetraselmis subcordiformis and the macroalga Ulva pertusa. Two new parameters, the maximum specific uptake rate (Vm^sp) and the maximal growth efficiency (β), are introduced to achieve uniformity for the comparison of nutrient uptake and growth efficiency between microalgae and macroalgae. T. subcordiformis possesses 3 times lower half saturation uptake constant, 4 times higher maximal growth rate and 20 times higher maximum specific uptake rate than U. pertusa, while U. pertusa possesses 4 times higher maximal growth efficiency than T. subcordiformis.     

工厂化培养蒙古裸腹溞研究

采用充氧培养的方法 ,研究了不同饵料和不同盐度、光照下蒙古裸腹的生长情况。结果表明 :投喂小球藻、亚心形扁藻、等鞭金藻时蒙古裸腹的增殖率分别为 4 0 6 .6 %、377%、32 2 .2 % ,差异并不明显 ,而投喂酵母的增殖率达到 86 6 .7% ,效果显著 ;在 10～ 30的盐度范围内 ,盐度为 10时增殖最快 ,增殖率为 382 % ;自然光和遮光对蒙古裸腹的增殖率为 375 .2 %和 - 0 .6 8% ,差异显著 ,其生长和繁殖需一定的光照。     

A Model Describing the Time Course and Variability in Toxicity of Hydrophobic Chemicals to Aquatic Organisms-Toxicity of chlorinated benzenes to marine algae

The growth of Chlorella marine, Nannochloris oculate, Pyramimonaos sp., Platymonas subcordiformis and Phaeodactylum tricornutum exposed to chlorobenzene, 1,2-dichlorobenzene, 1, 2, 3, 4-tetrachlorobenzene and pentachlorobenzene was tested. The Boltzman equation was used to describe organism growth. The time course for uptake of hydrophobic organic chemicals (HOCs) by aquatic organisms was expressed by incorporating growth and, if desired, the effect of metabolism into the HOC bioconcentration process. The probability of any given concentration of HOCs in the organisms causing a specified toxic endpoint was expressed with a modified Weibull distribution function. The combined bioconcentration and probability equations were tested with data for time course of incubation of algae exposed to chlorinated benzenes (CBs). A set of parameters, including the uptake rate constant k1, the elimination rate constant k2 and thereafter the bioconcentration factor on a dry weight basis, BCFD, the critical HOC concentration in the organism resulting in a specified toxic endpoint, C*A, and the spread factor, S, could be obtained by fitting only experimental data for percent growth inhibition(%)-time-CB exposure concentration. The average coefficients of variation within CBs were 15.2% for BCFD, 21.0%for k1, 18.3% for k2, 8.1% for C*A and 9.7% for S. The variability in toxicity (such as EC10, EC50, ECg0) derived from the model equations agreed well with those experimentally observed.     

Ingestion of <Emphasis Type="Italic">Brachionus plicatilis</Emphasis> under different microalgae conditions

The effects of four microalgae,Chlorella vulgaris,Platymonas helgolandicavar,Isochrysis galbana,and Nitzschia closterium on the grazing and filtering rates of the marine rotifer,Brachionus plicatilis,were evaluated under laboratory conditions.The grazing rates in separate cultures of the four microalga were as follows:C.vulgaris > P.helgolandicavar > I.galbana > N.closterium.However,the filtering rates occurred in the following order:P.helgolandicavar > N.closterium > C.vulgaris > I.galbana.A mixed diets ex...     

大珠母贝人工繁殖技术的研究

通过大珠母贝人工强化促熟、人工授精、幼虫对不同饵料的消化能力、新型采苗器的采苗以及标粗效果等实验,研究大珠母贝人工繁殖中的有关技术问题。结果表明:使用以骨条藻和天然硅藻做饵料促熟的大珠母贝亲贝进行人工授精可以获得质量较高受精率(达98%);用于亲贝人工授精的氨水溶液最佳浓度为体积分数10×10-6~30×10-6(氨水原液质量分数为25%~28%);D形幼虫对饵料的消化能力较差,宜投喂金藻和面包酵母,壳顶幼虫的消化能力强,宜增加扁藻混合投喂;在附着变态期采用新型的聚氯乙烯绳采苗器可以取得较传统附着板更好的采苗及标粗效果,单个采苗器可采壳长2 mm贝苗3.65万只,标粗40 d后贝苗平均成活率可达66.2%,壳长平均生长率可达295μm/d。     

Effect of benzo[a]pyrene on detoxification and the activity of antioxidant enzymes of marine microalgae

The objective of this study was to examine the effect of benzo[a]pyrene(Ba P) on the detoxification and antioxidant systems of two microalgae,Isochrysis zhanjiangensis and Platymonas subcordiformis.In our study,these two algae were exposed to Ba P for 4 days at three different concentrations including 0.5 μg~(L-1)(low),3 μg~(L-1)(mid) and 18 μg~(L-1)(high).The activity of detoxification enzymes,ethoxyresorufin O-deethylase(EROD) and glutathione S-transferase(GST) increased in P.subcordiformis in all Ba P-treated groups.In I.zhanjiangensis,the activity of these two enzymes increased at the beginning of exposure,and then decreased in the groups treated with mid-and high Ba P.The activity of antioxidant enzyme superoxide dismutase(SOD) increased in I.zhanjiangensis in all Ba P-treated groups,and then decreased in high Ba P-treated group,while no significant change was observed in P.subcordiformis.The activity of antioxidant enzyme catalase(CAT) increased in I.zhanjiangensis and P.subcordiformis in all Ba Ptreated groups.The content of malondialdehyde(MDA) in Isochrysis zhanjiangensis increased first,and then decreased in high Ba P-treated group,while no change occurred in P.subcordiformis.These results demonstrated that Ba P significantly influenced the activity of detoxifying and antioxidant enzymes in microalgae.The metabolic related enzymes(EROD,GST and CAT) may serve as sensitive biomarkers of measuring the contamination level of Ba P in marine water.     

Dynamic genetic features of eukaryotic plankton diversity in the Nakdong River estuary of Korea

Estuaries are environments where freshwater and seawater mix and they display various salinity profiles.The construction of river barrages and dams has rapidly changed these environments and has had a wide range of impacts on plankton communities.To understand the dynamics of such communities,researchers need accurate and rapid techniques for detecting plankton species.We evaluated the diversity of eukaryotic plankton over a salinity gradient by applying a metagenomics tool at the Nakdong River estuary in Korea.Environmental samples were collected on three dates during summer and autumn of 2011 at the Eulsukdo Bridge at the mouth of that river.Amplifying the 18 S rDNA allowed us to analyze 456 clones and 122 phylotypes.Metagenomic sequences revealed various taxonomic groups and cryptic genetic variations at the intra-and inter-specific levels.By analyzing the same station at each sampling date,we observed that the phylotypes presented a salinity-related pattern of diversity in assemblages.The variety of species within freshwater samples reflected the rapid environmental changes caused by freshwater inputs.Dinophyceae phylotypes accounted for the highest proportion of overall diversity in the seawater samples.Euryhaline diatoms and dinoflagellates were observed in the freshwater,brackish and seawater samples.The biological data for species composition demonstrate the transitional state between freshwater and seawater.Therefore,this metagenomics information can serve as a biological indicator for tracking changes in aquatic environments.     

The community structure and seasonal dynamics of plankton in Bange Lake,northern Tibet,China

The seasonal variations in biomass, abundance, and species composition of plankton in relation to hydrography were studied in the saline Bange Lake, northern Tibet, China. Sampling was carried out between one to three times per month from May 2001 to July 2002. Salinity ranged from 14 to 146. The air and water temperature exhibited a clear seasonal pattern, and mean annual temperatures were approximately 4.8°C and 7.3°C, respectively. The lowest water temperature occurred in winter from December to March at-2°C and the highest in June and July at 17.7°C. Forty-one phytoplankton taxa, 21 zooplankton, and 5 benthic or facultative zooplankton were identifi ed. The predominant phytoplankton species were Gloeothece linearis, Oscillatoria tenuis, Gloeocapsa punctata, Ctenocladus circinnatus, Dunaliella salina, and Spirulina major. The predominant zooplankton species included H olophrya actra, Brachionus plicatilis, Daphniopsis tibetana, Cletocamptus dertersi, and A rctodiaptomus salinus. The mean annual total phytoplankton density and biomass for the entire lake were 4.52×10~7 cells/L and 1.60 mg/L, respectively. The annual mean zooplankton abundance was 52, 162, 322, and 57, 144 ind./L, in the three sublakes. The annual mean total zooplankton biomass in Lakes 1–3 was 1.23, 9.98, and 2.13 mg/L, respectively. The annual mean tychoplankton abundances in Bg1, 2, and 3 were 47, 67, and 654 ind./L. The annual mean tychoplankton biomass was 2.36, 0.16, and 2.03 mg/L, respectively. The zooplankton biomass(including tychoplankton) in the lake was 9.11 mg/L. The total number of plankton species in the salt lake was signifi cantly negatively correlated with salinity.