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21.
通过对山东省靖海湾海蜇养殖港塭定期采样,采用稀释法研究该海蜇养殖港塭水体中浮游植物的生长率、微型浮游动物对浮游植物的摄食率、摄食压力以及微型浮游动物的生产力。研究结果表明,海蜇养殖港塭微型浮游动物组成比较简单,海蜇养殖期间微型浮游动物丰度低于海蜇捕捞结束期。其中,海蜇养殖期间微型浮游动物的优势种为根状拟铃虫(Tintinnopsis radix),为600~2 600 ind/L,而海蜇捕捞结束后优势种为根状拟铃虫、诺氏麻铃虫(Leprotintinnus nordquisti)和运动类铃虫(Codonellopsis mobilis),丰度分别为3 000~6 000、1 500~3 0001、500~3 000 ind/L。研究期间,该港塭浮游植物生长率为0.05~1.03 d-1。微型浮游动物的摄食率为0.24~2.37 d-1,对浮游植物现存量的摄食压力为21.10%~90.61%,对潜在初级生产力的摄食压力为77.08%~583.68%,而微型浮游动物的次级生产力占初级生产力的22.92%~76.92%。本研究表明微型浮游动物在海蜇养殖港塭生态系统物质和能量流动中起着重要作用。 相似文献
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2011年春夏季黄海和东海微型浮游动物类群组成及其摄食的研究 总被引：1，自引：0，他引：1
为了解春夏季黄海和东海微型浮游动物类群及其摄食生态,于2011年春季和夏季在黄海、东海,通过稀释法测定浮游植物生长率及微型浮游动物对浮游植物的摄食率,同时应用显微分析技术研究了微型浮游动物丰度及其类群组成．结果表明：（1）春季,黄海、东海微型浮游动物丰度为1800～21833个／dm3,夏季的为67～6175个／dm3;春季,其微型浮游动物生物量为8．71-60．58ug/dm3,夏季的则为0．44～30．25ug／dm3（其生物量以c含量计）．（2）春季、夏季黄海和东海浮游植物的生长率及其标准偏差分别为0．78±0．35、1．62±0．83d-1,而春季的显著低于夏季（P〈0．05）．春季、夏季其微型浮游动物的摄食率及其标准偏差分别为0．98±0．32、0．92±0．57d-1,无显著性差异（p〉0．05）．春季,微型浮游动物摄食浮游植物现有生物量的61％±13％,占初级生产量的131％±58％;夏季,微型浮游动物摄食浮游植物现有生物量的54％±22％,占初级生产量的70％±44％．春、夏季,黄海和东海微型浮游动物对浮游植物初级生产量的摄食比例较高． 相似文献
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The ciliate community in the Bohai Sea (China) was studied from 23 September to 7 October 1998. A hurricane struck the study area between the two grid station investigations, which were six days apart. Six tintinnid species ( Favella panamensis, Leptotintinnus nordqvisti, Tintinnopsis but-schlii, T. karajacensis , T. Radix and Wangiella dicollaria ) were identified. Total cililate abundance in the surface layer ranged from 20 to 770 ind/l. In the first grid investigation, Tintinnopsis karajacensis dominated in the warm, low salinity waters at the Huanghe River mouth. Aloricate ciliate sp. 1 dominated in the cold, high salinity waters in the northwest of the study area and the Bohai Strait. In the second grid investigation, T. Karajacensis almost disappeared. The abundance of aloricate ciliate sp. 1 decreased drastically. The aloricate ciliate sp. 2 dominated at the Bohai Strait. The change of ciliate abundance may be due to the disturbance of hurricane. 相似文献
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1INTRODUCTIONMicrozooplanktonsizecategoryiscomposedofdi versetaxonomicassemblages,includingplanktonicpro tozoa,larvalandnaupliarstagesofmetazoa(Gifford,1 988) .Microzooplanktonconstituteasignificantpro portionoftotalzooplanktonbiomassinavarietyofneri ticandoceanicenvironmentsandplayimportantrolesinplanktonicfoodwebs(FronemanandPerissinotto,1 996;Gallegos,1 989) .Severalmethodsforresearchonmi crozooplanktongrazingpressureonphytoplanktonwerereviewedbyMcManusandFuhrman (1 988)andGifford(1… 相似文献
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Within-day variability in ichthyoplankton and microzooplankton abundances was examined at a single station in Biscayne Bay using replicate tows of 61-cm bongo nets and Niskin bottles to determine if patchiness occurred on the 10–1000 m scale and on the minutes to hours time scale. Fish eggs and larvae often were patchy but copepod nauplii, the predominant food of larvae, usually were randomly distributed at the scales examined and over the 3.15 m-depth water column. Mean patchiness index values were of similar magnitude for fish eggs and larvae but fish eggs were patchy more often than were larvae. Individual taxa of larvae had extremely high patchiness index values on some dates. Variability in fish egg catches often reflected increasing or decreasing abundance trends during the 2.5h sampling period while fish larvae catches often appeared to be clumped within the repetitive series of tows. There was no tendency for patchiness to be correlated among taxa on collection dates nor was it correlated with abundances or wind speeds. Patchiness indices of bay anchovy Anchoa mitchilli eggs and larvae were not significantly correlated, indicating little concordance in tendency to be aggregated, suggesting that distributions were influenced by biological processes related to spawning of adults and behaviour of larvae, in addition to physical processes. Although ichthyoplankton patchiness often did exist at the 10–1000 m scale, on many days ichthyoplankton was uniformly or randomly distributed. Copepod nauplii were abundant (), randomly distributed on most dates, and apparently readily available as fish larvae food in Biscayne Bay. 相似文献
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R. Jyothibabu N.V. Madhu K.V. Jayalakshmi K.K. Balachandran C.A. Shiyas G.D. Martin K.K.C. Nair 《Estuarine, Coastal and Shelf Science》2006,69(3-4):505
The diversity, abundance and biomass of microzooplankton in Cochin backwaters were studied for the first time during pre-summer monsoon to peak of summer monsoon (April–July 2003) to understand the impact of large freshwater influx. Microzooplankton abundance and biomass were highest during pre-summer monsoon (av. 3817 ind. L−1 and 146 μg C L−1) that declined with the onset (av. 2052 ind. L−1 and 45 μg C L−1) and peak (av. 409 ind. L−1 and 10 μg C L−1) summer monsoon. Species diversity, richness and evenness of microzooplankton also showed similar trends as that of abundance and biomass. Grazing experiment showed that microzooplankton consumes 43 ± 1% of the daily phytoplankton standing stock during the high saline condition (27.5). Low abundance of microzooplankton during summer monsoon period (1/8 of the pre-summer monsoon value) along with the concomitant occurrence of low mesozooplankton (1/8 times of pre-summer monsoon value) suggests that there could be a general lack of planktonic grazers. This would result in a weak transfer of primary and bacterial carbon to higher trophic levels, eventually leaving behind much unconsumed basic food in the estuary during summer monsoon. Thus a major portion of the primary carbon either settles down or gets transported to the coastal regions during monsoon. High flushing of Cochin backwaters also facilitates faster removal of primary producers to the coastal regions during monsoon. 相似文献
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Abstract. Microzooplankton grazing and protozooplankton community structure was investigated in austral summer (Jan./Feb.) and winter (June/July) 1993 in the Atlantic sector of the Southern Ocean during the SAAMES (South African Antarctic Marine Ecosystem Study) Il and III cruises. Grazing was estimated at 22 stations in summer and at 15 stations in winter by employing the sequential dilution technique. Nano-heterotrophic flagellates (< 20 μm) and ciliates (aloricate ciliates and tintinnids) dominated the protozooplankton assemblages along both transects. Densities in winter were, however, nearly an order of magnitude lower than in summer. Microzooplankton grazing removed between 0 and 28% (mean = 13.2%) of the initial phytoplankton stock in summer and, between 24 and 51 % of the initial stock (mean = 37.6%) in winter. The potential primary production removed during summer ranged between 0 and 46% (mean = 22.0%) compared with the winter range of 56–83% (mean = 67.2%). Size selectivity grazing experiments conducted during both studies suggest that microzooplankton preferentially graze on the nano- (20–2.0μm) and picophytoplankton (2.0–0.2μm) size fractions. These results have important implications for the efficiency of the carbon pump in the Southern Ocean. During summer when the larger cells dominate phytoplankton biomass, the bulk of the photosynthetically fixed carbon appears to be channelled to the meso- and macrozooplankton fractions. This results in a rapid transfer of organic carbon out of the zone of regeneration to the deep ocean via vertical migration and large faecal pellet production. During winter, however, an increase in the contribution of the smaller size fractions to total phytoplankton biomass results in a greater proportion of the photosynthetically fixed carbon being channelled to the microzooplankton fraction. The efficiency of the carbon pump is, therefore, reduced in that the transfer of carbon below the zone of regeneration is reduced as carbon is recycled mostly within the microbial loop in the upper mixed layer. 相似文献
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2005年7月在台湾海峡南部4个站位应用“稀释法”结合高效液相色谱(HPLC)色素分析技术研究了不同色素类群浮游植物的生长率及微型浮游动物对其的摄食死亡率.结果表明,不同色素类群浮游植物的生长率(k)和摄食死亡率(g)分别为0.52～ 1.34 d-1和0.25 ～ 1.10 d-1,微型浮游动物对不同色素类群浮游植物的现存量和初级生产力的摄食压力分别为22％～ 66％和40％～ 151％.通过比较不同类群浮游植物的g/k值,发现颗粒较大的浮游植物(硅藻和甲藻)的净生长率要大于那些微型藻类(蓝细菌、隐藻和定鞭金藻等)的净生长率,说明本次研究中微型藻类更易受到微型浮游动物的摄食控制. 相似文献
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Studies on growth rate and grazing mortality rate by microzooplankton of size-fractionated phytoplankton in spring and summer in the Jiaozhou Bay, China 总被引：15，自引：2，他引：13
1 Introduction Phytoplankton has been considered as a dom inantprim ary producer in m arine ecosystem s, starting them arine food chain (N ing and V aulot.,2003;Sun etal.,2001; Zhu et al., 2000; N ing and V aulot, 1992). A l-though potentialfates ofphytoplankton include advec-tion,verticalm ixing,sinking and m ortality due to virallysis and grazing (B anse,1994),m ortality due to graz-ing,especially by m icrozooplankton,is generally con- μm m esh to 25-L carboys, then transpo… 相似文献