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1.
Crustacean zooplankton form the keystone link between primary producers and fish stocks in marine and estuary ecosystems.
We have established a multi-generation cultivation system for zooplankton with which future experiments on the biological
effects of pollutants in marine and estuary environments can be better performed. A population of calanoid copepod, Schmakeria poplesia, was collected in December 2003 and maintained in a static system through all stages (eggs to adults). The population exhibited
an average developmental time of 13.6 d in conditions corresponding to the natural environment (water temperature 20°C, salinity
15). A series of experiments were performed to examine copepod egg production and hatching success as functions of food type
and feeding concentration. Results in our study showed that Isochrysis galbana was more favored for the reproduction of copepods than Phaeodactylum tricornutum, and 10×104cells mL−1 was the most practical algae concentration. We have demonstrated that the Schmakeria poplesia population can be maintained in the laboratory through multiple generations. In addition, methods to control egg production
through changes in food concentration have been established, making it feasible to control the start date of exposure experiments
or the timing of the collection of offspring to initiate a new generation. 相似文献
2.
A full life-cycle toxicity test,combined with histology,on calanoid copepod Schmackeria poplesia was used to study the effect of bis(tributyltin)oxide(TBTO).The results indicate no sex-specific differences in TBTO toxicity.Long-term mortalities of the copepods exposed to concentrations higher than 20 ng TBTO L-1were significantly elevated compared with that of control,and larval development was inhibited when they were exposed to 40 and 60 ng TBTO L-1.The percentages of ovigerous females were reduced compared with the control(P0.01)after 24 days exposure to concentrations higher than 10 ng TBTO L-1.Histological examinations suggest that exposure to TBTO might block the posterior end of the diverticula and inhibits the production of egg sacs.A modified Euler-Lotka equation was used to calculate a population-level endpoint,the intrinsic rate of natural increase(rm),from individual life-table endpoints,i.e.mortality rate,time of release of first brood,sex ratio,the fraction of ovigerous females among all females as well as the number of nauplii per ovigerous female.Apart from the highest TBTO concentration(60 ng L-1),where all females aborted their egg sacs,20 ng TBTO L-1was the only concentration that significantly decreased rm compared with that of control(an effect associated with decreased sex ratio).The results show that the S.poplesia is affected by prolonged exposure to low concentrations of TBTO.The full life-cycle toxicity test combined with histology experiments provides more integral understanding of the toxicity of endocrine disrupters. 相似文献
3.
Zooplankton spatial and diurnal variations in the Changjiang River estuary before operation of the Three Gorges Dam 总被引：1，自引：0，他引：1
Estuarine plankton communities can serve as indicators of ecosystem modification in response to anthropogenic influences. The main objectives of this study were to describe the spatial distribution and diurnal variability in zooplankton abundance and biomass over almost entire salinity gradient of the Changjiang (Yangtze) River estuary and to provide a background reference for future studies. To accomplish this, data were collected from 29 stations in the estuary from May 19 to 26, 2003, including two anchor stations. The spatial and diurnal variations in zooplankton characteristics, i.e. abundance, biomass, and gross taxonomic composition, were examined. Generally, both the abundance and biomass gradually increased seaward and presented distinct spatial variations. In addition, the spatial data revealed a significant correlation between abundance and biomass; however, there was no significant correlation between abundance and biomass for the diurnal data. Although the zooplankton composition indicated distinct spatial differences in terms of dominant groups, copepods accounted for >50% of the total zooplankton abundance in most regions and times. Three zooplankton assemblages were recognized through hierarchical cluster analysis. These assemblages existed along the salinity gradient from fresh water to seawater, and their positions coincided with those of the three principal water masses in the estuary. The assemblages were classified as: (1) true estuarine, (2) estuarine and marine, and (3) euryhaline marine, which were characterized by the copepods Sinocalanus dorrii, Labidocera euchaeta, and Calanus sinicus, respectively. Both spatial and diurnal data indicated that there was no significant correlation between zooplankton abundance/biomass and depth-integrated phytoplankton abundance. 相似文献
4.
S. K. Baliarsingh Suchismita Srichandan Aneesh A. Lotliker T. Srinivasa Kumar K. C. Sahu 《中国海洋大学学报(英文版)》2018,17(4):879-889
An interannual study on zooplankton abundance, biomass, and species composition was carried out during different seasons in two local coastal water types off Gopalpur, north-western Bay of Bengal. Although, Type-1 was observed with higher zooplankton abundance in comparison to Type-2, pattern of variation followed similar seasonal trends in both water types during individual years. Well pronounced seasonality was observed in zooplankton distribution. Zooplankton community was composed of 217 holoplankton and 22 meroplankton. The holoplankton community was predominated by copepod in terms of species diversity and abundance followed by hydrozoa, tintinnida, malacostraca, gastropoda, chaetognatha and chordata. The meroplankton were represented by larval forms viz. bivalve veliger, brachyuran zoea larvae, caridean larvae, copepod nauplii, fish egg and gastropod veliger. Dominance of copepod species viz. Acrocalanus longicornis, Paracalanus aculeatus and Paracalanus parvus were observed frequently in both water types. The species richness was higher in Type-1 in comparison to Type-2 during both the years. Salinity regimes and availability of phytoplankton prey influenced the distribution and species composition of zooplankton assemblage. 相似文献
5.
Primers to block the amplification of symbiotic apostome ciliate 18S rRNA gene in a PCR-based copepod diet study 总被引：1，自引：0，他引：1
Pelagic copepods play an important role in the marine food web. However, a full understanding of the ecological status of this zooplankton group depends on the careful study of their natural diets. In previous PCR-based copepod diet studies, we found many apostome ciliates that live symbiotically under the exoskeleton of the copepods, and their sequences were often over-represented in the 18S rRNA gene （18S rDNA） libraries. As a first step to address this issue, we designed three apostome ciliate 18S rDNA blocking primers, and tested their blocking efficiency against apostome ciliate 18S rDNA under various PCR conditions. Using a semi-quantitative PCR method, we optimized the conditions to efficiently amplify the 18S rDNA of the prey while simultaneously excluding the symbiotic apostome ciliates. This technique will facilitate PCR-based diet studies of copepods and other zooplankton in their natural environments. 相似文献
6.
DNA barcoding provides accurate identification of zooplankton species through all life stages. Single-gene-targeted metagenomic analysis based on DNA barcode databases can facilitate longterm monitoring of zooplankton communities. With the help of the available zooplankton databases, the zooplankton community of the Changjiang (Yangtze) River estuary was studied using a single-gene-targeted metagenomic method to estimate the species richness of this community. A total of 856 mitochondrial cytochrome oxidase subunit 1 (cox1) gene sequences were determined. The environmental barcodes were clustered into 70 molecular operational taxonomic units (MOTUs). Forty-two MOTUs matched barcoded marine organisms with more than 90% similarity and were assigned to either the species (similarity>96%) or genus level (similarity<96%). Sibling species could also be distinguished. Many species that were overlooked by morphological methods were identified by molecular methods, especially gelatinous zooplankton and merozooplankton that were likely sampled at different life history phases. Zooplankton community structures differed significantly among all of the samples. The MOTU spatial distributions were influenced by the ecological habits of the corresponding species. In conclusion, single-gene-targeted metagenomic analysis is a useful tool for zooplankton studies, with which specimens from all life history stages can be identified quickly and effectively with a comprehensive database. 相似文献
7.
Reproductive rate of a marine planktonic copepodLabidocera euchaeta Giesbrecht in Xiamen Harbor bor was studied during the period from April 1986 to August 1987. Results showed that rate of
egg production (F, eggs/(♀, d)) was positively correlated with temperature (T,oC) and body weight of spawning female (Wc, μgC) as:F=0.0637 (T−7)0.7445
Wc. Each month a maximum rate of egg production occurred at one of the five experimental temperatures (10°, 15°, 25°, and 30°C)
near the monthly mean field temperature. The available food density (P, μgC/ml) had significant effect on specific rate of egg production (Fc, %C ♀/d) as:Fc=0.1732 (P-0.0179)/P. The gross efficiency of egg production of ca 62% in carbon was independent of food density snd ingestion rate. Observations
on in situ egg production and hatching rate demonstrated that this species reproduces continuously all the year round, with
summer as its high reproductive season and winter a low one. Ten generations a year is also suggested based on the number
of the peaks of average population egg production rate. This agreed well with the result obtained from the generation-time
equations. Egg-laying pattern was also observed and discussed. 相似文献
8.
ZOOPLANKTON COMMUNITY STRUCTURE OF THE SEA SURFACE MICROLAYER NEAR NUCLEAR POWER PLANTS AND MARINE FISH CULTURE ZONES IN DAYA BAY 总被引：1，自引：0，他引：1
ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｓｅａｓｕｒｆａｃｅｍｉｃｒｏｌａｙｅｒ (ＳＭ)ｗｉｔｈｓｐｅｃｉａｌｐｈｙｓｉｃａｌ,ｃｈｅｍｉｃａｌａｎｄｂｉｏｌｏｇｉｃａｌｐｒｏｐｅｒｔｉｅｓ,ｈａｄｂｅｅｎｗｅｌｌｄｅｓｃｒｉｂｅｄａｓａｓｉｔｅｏｆｉｎｔｅｎｓｉｖｅａｃｃｕｍｕｌａｔｉｏｎｏｆｄｉｓｓｏｌｖｅｄａｎｄｐａｒｔｉｃｕｌａｔｅｏｒｇａｎｉｃｍａｔ ｔｅｒｉｎｖｏｌｖｉｎｇｐｈｙｔｏｐｌａｎｋｔｏｎａｎｄｂａｃｔｅｒｉａ (Ｈａｒｄｙ,1 982 ) .Ｔｈｉｓｅｎｖｉｒｏｎｍｅｎｔｈａｓｇｒｅａｔｉｍｐｏｒ… 相似文献
9.
Most urban rivers play an important role in urban flood control and drainage in China, but pollution is fast becoming an issue of greater importance in water management. In this study, 63 zooplankton species were recorded in four downtown rivers in Shanghai between November 2007 and October 2008. Of these, 44 species belonged to the Rotifera, 13 to Cladocera, and six to Copepoda. The three most frequently occurring zooplankton （Brachionus calyciflorus, Microcyclops Ieuckarti, and Asplanchna priodonta） accounted for 80.00%, 76.84%, and 53.68%, respectively. Rotifera were found to be dominant, comprising 86.26% of total zooplankton, while cladoceran and copepod abundance amounted to 5.08% and 8.67%, respectively. Water temperature, salinity, electrical conductivity, and total nitrogen were of the greatest significance in the occurrence of zooplankton. Two species （Schmackeria forbesi and Lepadella ovalis） were notably more sensitive to environmental factors such as salinity and electrical conductivity than other species. The population size and community were inversely correlated with the increasing nutrient levels of the four rivers, suggesting that the water quality of the four rivers had been gradually recovering from a severe eutrophic state and that water conditions of the rivers had been gradually improved. 相似文献
10.
车志伟 《广东海洋大学学报》2007,27(6):89-92
<正>河流入海口及感潮河段是陆海相互作用藕合带[1],受径流和潮汐的共同作用,具有独特的海洋环境。三亚河位于三亚湾的东侧,是注入三亚湾的最大河流,其流程28.8 km,集雨面积337.02 km2,河床平均坡降6.09‰,总落差459.21 m,三亚河属潮汐河流,平均每日纳潮量达490万立方米,年径流量为179亿立方米,现实际日纳潮量为253立方米、年径流量为92亿立方米。近年来,国内学者已对三亚湾海域开展了若干研究,如中国科学院南海海洋研究所何雪琴[2]、南京大学海岸与海岛开发教育部重点实验室毛龙江等[3]都先后报道过三亚湾的研究结果,但对三亚河口及感潮段悬浮物分布的研究目前尚未见报道。本文通过分析监测结果,研究了三亚河入海口及感潮河段悬浮物分布特征和潮汐对其影响。 相似文献
11.
黄河入海口水域春季浮游动物群落特征研究 总被引：3，自引：0，他引：3
对2008、2009年黄河入海口水域春季浮游动物进行调查,采用香农-威纳多样性指数(Shannon-Weiner index)、Pielou均匀度指数和McNaugton优势度指数对其浮游动物群落特征进行分析。结果表明:浮游动物鉴定出6大类44种,以甲壳动物种类最多;2008年5月黄河入海口水域浮游动物多样性指数范围为0.92～2.65,均匀度变化范围为0.25～0.66;2009年5月浮游动物多样性指数范围为0.76～2.87,均匀度变化范围为0.21～0.70。黄河入海口水域浮游动物时空分布较不均匀,群落特征(包括丰度、多样性指数、均匀度和优势度等)在同一时期同一水域各采样点间差异较大,同一采样点不同年份差异显著。 相似文献
12.
车志伟 《广东海洋大学学报》2007,27(6):89-92
河流入海口及感潮河段是陆海相互作用藕合带，受径流和潮汐的共同作用，具有独特的海洋环境。三亚河位于三亚湾的东侧，是注入三亚湾的最大河流，其流程28．8km，集雨面积337．02km^2，河床平均坡降6．09‰，总落差459．21m，三亚河属潮汐河流，平均每日纳潮量达490万立方米，年径流量为179亿立方米，现实际日纳潮量为253立方米、年径流量为92亿立方米。近年来，国内学者已对三亚湾海域开展了若干研究，如中国科学院南海海洋研究所何雪琴、南京大学海岸与海岛开发教育部重点实验室毛龙江等都先后报道过三亚湾的研究结果，但对三亚河口及感潮段悬浮物分布的研究目前尚未见报道。本文通过分析监测结果，研究了三亚河入海口及感潮河段悬浮物分布特征和潮汐对其影响。 相似文献
13.
Sexual reproduction adversely affects the population growth of cyclic parthenogenetic animals. The density-dependent sexual reproduction of a superior competitor could mediate the coexistence. However,the cost of sex may make the inferior competitor more vulnerable. To investigate the effect of sexual reproduction on the inferior competitor,we experimentally paired the competition of one Brachionus angularis clone against three B rachionus calyciflorus clones. One of the B. calyciflorus clones showed a low propensity for sexual reproduction,while the other two showed high propensities. The results show that all B. calyciflorus clones were excluded in the competition for resources at low food level. The increased food level promoted the competition persistence,but the clones did not show a clear pattern. Both the cumulative population density and resting egg production increased with the food level. The cumulative population density decreased with the mixis investment,while the resting egg production increased with the mixis investment. A trade-off between the population growth and sexual reproduction was observed in this research. The results indicate that although higher mixis investment resulted in a lower population density,it would not determinately accelerate the exclusion process of the inferior competitor. On the contrary,higher mixis investment promoted resting egg production before being excluded and thus promised a longterm benefit. In conclusion,our results suggest that mixis investment,to some extent,favored the excluded inferior competitor under fierce competition or some other adverse conditions. 相似文献
14.
Zooplankton abundance, biovolume and taxonomic composition in Jiaozhou Bay and the adjacent coastal Yellow Sea were evaluated using ZooScan measurement of samples collected by net towing every August from 2005 to 2012. Zooplankton abundance and biovolume ranged from 1 938.5 to 24 800 ind./m~3 and 70.8 to 1 480.1 mm~3/m~3 in Jiaozhou Bay and 73.1 to 16 814.3 ind./m~3 and 19.6 to 640.7 mm~3/m~3 in the coastal Yellow Sea. Copepods were the most abundant group in both regions, followed by N octiluca scintillans and appendicularians in Jiaohzou Bay, and chaetognaths and N octiluca scintillans in adjacent coastal Yellow Sea. Over the study period, the most conspicuous hydrographic change was an increase in water temperature. Meanwhile, a general decrease in zooplankton abundance was observed, particularly in copepod populations. Based on redundancy analysis(RDA), the warming trend was the key environmental factor influencing to decrease of copepod abundance. The proportion of small-sized copepods increased while the mean size of all copepods decreased, in significant correlation with water temperature. Our results indicate that zooplankton, particularly copepods, are highly sensitive to change in water temperature, which is consistent with predicted impacts of warming on aquatic ectotherms. Due to their dominance in the zooplankton, the decline in copepod size and abundance could lead to an unfavourable decrease in energy availability for predators, particularly planktivorous fish. 相似文献
15.
COUPLED PHYSICAL-ECOLOGICAL MODELLING IN THE CENTRAL PART OF JIAOZHOU BAY Ⅱ.COUPLED WITH AN ECOLOGICAL MODEL 总被引：2，自引：0，他引：2
Sharpies‘ 1-D physical rrozlel maploying tide-wind driven turbulence closure and surface heating-cooling physics, was coupled with an eculogical rnodet with 9-biochemical components: phytoplankton, zooplankton, shellfish, autotmphic and heterotrophic bacterioplankton, dissolved organic carbon (DOC), suspended detritus and sinking particles to simulate the armual evolution of ecosystem in thecentral part of Jiaozhou Bay. The coupled modeling results showed that the phytoplankton shading effectcould reduce seawater temperamre by 2℃, so that photosynthesis efficiency should be less than 8% ; that the loss of phytoplankton by zooplankton grazing in winter tended to be compensated by phytoplankton advection and diffusion from the otrtside of the Bay; that the incidem irradiance intensity could be the mostimportant factor for phytoplankton grcr, wth rate; and that it was the bacterial secondary prnduction that maintained the maximum zooplankton biomass in winter usually observed in the 1990s, indicating that themicrobial food loop was extremely important for ecosystem study of Jiaozhou Bay. 相似文献
16.
Zooplankton constitutes a major part of the diet for fish larvae in the marine food web, and it is generally believed that
copepods can meet the nutritional requirements of fish larvae. In this study, calanoid copepod Schmackeria poplesia, rotifer Brachionus plicatilis and anostraca crustacean Artemia sp. were analyzed for fatty acid contents, and were used as live food for culturing larval Japanese flounder, Paralichthys olivaceus. The total content of three types of HUFAs (DHA, EPA and ARA) in S. poplesia was significantly higher than that in the other two live foods (P<0.01). Three live organisms were used for raising larvae and juveniles of Paralichthys olivaceus respectively for 15 and 10 d. Then the growth, survival and fatty acid composition of the larvae and juveniles were investigated.
The results showed that the larvae and juveniles fed with copepods (S. poplesia) had significantly higher growth rate than those fed with the other two organisms (P<0.01). The survival of the flounder larvae fed with copepods was significantly higher than that of the others (P<0.01), and the survival of the juvenile fish fed with copepods was higher than that fed with Artemia (P<0.05). The contents of three types of HUFAs (DHA, EPA and ARA) and the ratio of DHA/EPA in larval and juvenile flounder P. olivaceus were analyzed. The results showed that the contents of DHA, EPA and ARA in the larvae and juveniles fed with S. poplesia were higher than those fed with a mixed diet or Artemia only, and the ratio of EPA/ARA in larvae and juveniles of P. olivaceus fed with S. poplesia was lower than that in the case of feeding with a mixed diet or Artemia only. The present data showed that copepod is the best choice for feeding the larvae and juveniles of fish considering its
effects on the survival, growth and nutrition composition of the fish. 相似文献
17.
A full life-cycle toxicity test, combined with histology, on calanoid copepod Schmackeria poplesia was used to study the effect of bis(tributyltin) oxide (TBTO). The results indicate no sex-specific differences in TBTO toxicity.
Long-term mortalities of the copepods exposed to concentrations higher than 20 ng TBTO L−1 were significantly elevated compared with that of control, and larval development was inhibited when they were exposed to
40 and 60 ng TBTO L−1. The percentages of ovigerous females were reduced compared with the control (P<0.01) after 24 days exposure to concentrations higher than 10 ng TBTO L−1. Histological examinations suggest that exposure to TBTO might block the posterior end of the diverticula and inhibits the
production of egg sacs. A modified Euler-Lotka equation was used to calculate a population-level endpoint, the intrinsic rate
of natural increase (r
m), from individual life-table endpoints, i.e. mortality rate, time of release of first brood, sex ratio, the fraction of ovigerous
females among all females as well as the number of nauplii per ovigerous female. Apart from the highest TBTO concentration
(60 ng L−1), where all females aborted their egg sacs, 20 ng TBTO L−1 was the only concentration that significantly decreased r
m compared with that of control (an effect associated with decreased sex ratio). The results show that the S. poplesia is affected by prolonged exposure to low concentrations of TBTO. The full life-cycle toxicity test combined with histology
experiments provides more integral understanding of the toxicity of endocrine disrupters. 相似文献
18.
《中国海洋湖沼学报》2018,(6)
A considerable part of the world's population is currently experiencing a severe scarcity of freshwater and nutrition. Inland aquaculture has the fastest growth in fresh waters, and this contributes to the eutrophication of freshwater bodies. The increase in freshwater aquaculture impacts on the increasing demand for fresh water. A way to overcome this is to develop aquaculture in saline lakes. This article discusses how saline and hypersaline lakes may contribute to overcome this problem and gives a list of fish and shrimp species that can be cultivated in saline lakes. Successful development of aquaculture depends on a healthy cultured stock of commercial fish and shrimps. A sustainable healthy stock of fish and shrimps can be only maintained using live food for the cultured fish larvae, fry and fingerlings. As well as Artemia spp. there are many other crustacean species with the potential for growing in hypersaline waters. At least 26 copepod species around the world can live at a salinity above 100 g/L with 12 species at a salinity higher than 200 g/L, and these all have excellent nutritional value. There is a high potential to use eukaryotic organisms of diff erent taxa in saline/hypersaline aquaculture for food, agri-aquaculture, diff erent industries and as food supplements. 相似文献
19.
ＩＮＴＲＯＤＵＣＴＩＯＮＪｏｈａｎｎｅｓ (1 965)ｆｉｒｓｔｓｈｏｗｅｄｔｈｅｉｍｐｏｒｔａｎｃｅｏｆｐｒｏｔｏｚｏａａｓｒｅｍｉｎｅｒａｌｉｚｅｒｓｉｎｍａｒｉｎｅｅｎｖｉｒｏｎｍｅｎｔｓ.Ｔｈｅｓｉｇｎｉｆｉｃａｎｃｅｏｆｐｒｏｔｏｚｏａｉｎｔｈｅｆｒｅｓｈｗａｔｅｒｆｏｏｄｗｅｂｈａｓｂｅｅｎｋｎｏｗｎｆｏｒｔｈｅｐａｓｔ2 0ｙｅａｒｓ.Ｐｒｏｔｏｚｏａｉｓａｍａｉｎｐｒｅｄａｔｏｒｏｆｐｌａｎｋｔｏｎｉｃｂａｃｔｅｒｉａａｎｄｐｈｙｔｏｐｌａｎｋｔｏｎ ,ａｎｄａｌｓｏａｆｏｏｄｓｏｕｒｃｅｏ… 相似文献
20.
Seasonal change in body length of important small copepods and relationship with environmental factors in Jiaozhou Bay,China 总被引：1，自引：0，他引：1
Differences among species in prosome length and in species’ response to environmental factors do exist. Therefore, it is useful to examine prosome length for different copepod species in variable environments. Seasonal variations in prosome length of four small copepods and their copepodite stages in the Jiaozhou Bay were compared and the relative influence of temperature, salinity, and chlorophyll concentration were examined. Two peaks were found in the mean prosome length of Paracalanus parvus (in early winter and May). For Acartia bifilosa, the maximum values of all copepodites occurred mainly from February to April, and decreased to the bottom in July. Prosome length of Acartia pacifica peaked when it first appeared in June, then reached to the minimum in July. Parvocalanus crassirostris only appeared from late summer to autumn and the mean prosome length showed no clear changes. Correlations of adult prosome length with environmental factors were evaluated. For the four species, temperature was negatively correlated to prosome length except for P. crassirostris. But the different species varied markedly in their responds to temperature. A. bifilosa showed a more definite trend of size variation with temperature than P. parvus and A. pacifica. Correlations of prosome length with salinity were significantly positive for almost all the small copepods. The relationship between chlorophyll concentration and prosome length was complicated for these copepods, but for P. parvus, chlorophyll concentration was also an important affecting factor. Furthermore, investigation needs to be done on food quality for some copepod. These results are essential to estimate the biomass and the production, and to understand these small copepods’ population dynamics in this human-affected bay. 相似文献