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1.
Mesozooplankton biomass and abundance were evaluated in epipelagic waters at 59 stations covering the Italian sector of the
Ligurian Sea (north-western Mediterranean) in December 1990. This region is characterised by a cyclonic circulation which
encloses a central divergence zone and is associated with a main thermohaline front offshore the western Ligurian coast. At
the end of autumn, mesozooplankton biomass (range: 0.80–4.24 mg DW m−3) and the abundance (range: 83.8–932 ind. m−3) were lower in the divergence zone. On the contrary, in the Ligurian frontal zone at the periphery of the divergence and
on the eastern continental shelf the greatest values of biomass and abundance were recorded. Copepods and appendicularians
dominated the mesozooplankton community, the main taxa being the copepods Clausocalanus spp. (46% of total zooplankton) and Oithona spp. (15%) and the appendicularian Fritillaria spp. (12%). Three hydrological sub-regions, i.e. the divergence, the eastern continental shelf and the periphery of the divergence,
were characterised by different zooplankton communities and characteristic species. Environmental differences between the
three zones were mainly related to changes in bottom topography, sea surface temperatures and quantity of particulate organic
matter. Vertical mesozooplankton abundance and taxa distribution from the surface to 1,900 m depth were also examined in one
station. The results showed that the bulk of the community was concentrated in the upper 200 m, small copepods being dominant
particularly in the upper 50 m. The copepod community was more diversified in sub-superficial waters, with a maximum observed
in the 200–400 m layer. The distributions of main zooplankton taxa described in epipelagic waters in the eastern Ligurian
Sea in autumn were compared with their distribution at surface in the north-western Mediterranean obtained by sampling performed
with the Continuous Plankton Recorder in 1997–1999. The analysis of the zooplankton community in CPR samples confirms the
dominance of small copepods (Paracalanus spp., Clausocalanus spp., Oithona spp.) and appendicularians in the north-western Mediterranean in late autumn-winter and shows that their distribution is
mainly related to the main mesoscale hydrographic features characterising this basin.
Guest editors: S. Souissi & G. A. Boxshall
Copepoda in the Mediterranean: Papers from the 9th International Conference on Copepoda, Hammamet, Tunisia 相似文献
2.
Copepods are considered to be the main component of the Arctic marine zooplankton. We examined the copepod distribution and
diversity off Franz Josef Land (northern Barents Sea) in August 2006 and 2007. A total of 18 and 14 copepod taxa were identified
from the sampling layers (100–0 m or bottom–0 m) in 2006 and in 2007, respectively. There were no significant differences
in the total copepod abundance between the years (means ± SE: 118,503 ± 24,115 individuals m−2 in 2006 vs. 113,932 ± 28,564 individuals m−2 in 2007). However, the copepod biomass in 2006 (4,518 ± 1,091 mg C m−2) exceeded clearly the value in 2007 (1,253 ± 217 mg C m−2). The copepod community showed low species richness and diversity in both years (Simpson index D: 0.34 and 0.38, respectively).
Biomass of the large and small copepod species strongly decreased from 2006 to 2007. The total abundance of copepods was negatively
correlated with water temperature in 2006 and positively correlated with salinity in 2007. The patchiness in copepod distribution
was associated with local hydrography and temperature conditions. 相似文献
3.
The community structure of mesozooplankton was investigated in Dolgaya Bay (southern Barents Sea), a subarctic fjord, using
a Juday net (0.168-mm mesh size) in July, 2008. A total of 39 species and higher taxa were found. Average abundance, biomass
and diversity (±standard error) were 153,403 ± 15,855 ind m−2, 570 ± 61 mg dry mass m−2, and 2.25 ± 0.09, respectively. Copepods were the most numerous species. The mesozooplankton communities were dominated by
omnivores (Oithona similis and Acartia spp.). Vertical distribution of the mesozooplankton was characterized by copepod dominance at each sampled layer. There were
no significant correlations among physical variables and biological parameters, except negative correlation for the mean biomass
and mean water temperature. 相似文献
4.
The summer Phaeocystis antarctica bloom increases under-ice phytoplankton biomass in McMurdo Sound, Antarctica. The magnitude of mesozooplankton grazing on
this bloom is unknown, and determines whether this production is available to the pelagic food web. We measured mesozooplankton
abundance and body content of dimethylsulfoniopropionate (DMSP) during the McMurdo Sound austral summer (2006 and 2006–2007).
Abundance varied from 20 to 4,500 ind. m−3 (biomass 0.02–274.0 mg C m−3), with peaks in mid-December and late-January/February. Abundance was higher but total zooplankton biomass lower in our study
compared to previous reports. Copepods and the pteropod Limacina helicina dominated the zooplankton in both abundance and biomass. DMSP was detected in all zooplankton groups, with highest concentrations
in copepod nauplii and L. helicina (95 and 54 nmol mg−1 body C, respectively). Experiments suggested that L. helicina obtains DMSP by directly grazing on P. antarctica, which often accumulates to high biomass under the summer sea ice in McMurdo Sound. 相似文献
5.
The structure of the zooplankton community in an estuary adjacent to the Admiral álvaro Alberto Nuclear Power Plant at Angra
dos Reis, state of Rio de Janeiro, Brazil was studied from 2001 through 2005. At that time, the power plant had been operating
for 20 years. The results were compared with a previous study in 1991–1993. The zooplankton was sampled 4 times a year, in
vertical hauls using a 150 μm net, at two fixed points near the plant’s intake and discharge sites. Temperature, salinity,
and chlorophyll a were measured. The water of Ribeira Bay is warm, with salinities typical of Coastal Water and more saline waters. Zooplankton
density at the discharge site (Mean: 245,434 ind m−3, SD: 335,358 ind m−3) was higher than that at the intake site (Mean: 84,634 ind m−3, SD: 101,409 ind m−3). A total of 121 mesozooplankton taxa were recorded from 2001 to 2005. Copepoda constituted the most common taxon and comprised
more than 57% of the total zooplankton, followed by cladocers and gastropod larvae. A seasonal zooplankton cycle was observed
only during 2004; in other years, the plankton varied only between years. Overall mesozooplankton abundance at the discharge
site was similar to levels reported from the inner zone of this estuary in 1991–1993. Surface temperature was the important
factor structuring the zooplankton community at the discharge site. No effect on the mesozooplankton by passage through the
condensers could be discerned, and no permanent negative influence on the plankton populations could be detected.
Guest editors: U. M. Azeiteiro, I. Jenkinson & M. J. Pereira
Plankton Studies 相似文献
6.
Landfast ice algal communities were studied in the strongly riverine-influenced northernmost part of the Baltic Sea, the Bothnian
Bay, during the winter-spring transition of 2004. The under-ice river plume, detected by its low salinity and elevated nutrient
concentrations, was observed only at the station closest to the river mouth. The bottommost ice layer at this station was
formed from the plume water (brine volume 0.71%). This was reflected by the low flagellate-dominated (93%) algal biomass in
the bottom layer, which was one-fifth of the diatom-dominated (74%) surface-layer biomass of 88 μg C l−1. Our results indicate that habitable space plays a controlling role for ice algae in the Bothnian Bay fast ice. Similarly
to the water column in the Bothnian Bay, average dissolved inorganic N:P-ratios in the ice were high, varying between 12 and
265. The integrated chlorophyll a (0.1–2.2 mg m−2) and algal biomass in the ice (1–31 mg C m−2) correlated significantly (Spearman ρ = 0.79), with the highest values being measured close to the river mouth in March and during the melt season in April. Flagellates
<20 μm generally dominated in both the ice and water columns in February–March. In April the main ice-algal biomass was composed
of Melosira arctica and unidentified pennate diatoms, while in the water column Achnanthes taeniata, Scrippsiella hangoei and flagellates dominated. The photosynthetic efficiency (0.003–0.013 (μg C [μg chl a
−1] h−1)(μE m−2s−1)−1) and maximum capacity (0.18–1.11 μg C [μg chl a
−1] h−1) could not always be linked to the algal composition, but in the case of a clear diatom dominance, pennate species showed
to be more dark-adapted than centric diatoms. 相似文献
7.
Mesozooplankton distribution was investigated under the sea ice in the Kara Sea at five stations in February of 2002 by Juday
net hauls. Copepods dominated the mesozooplankton community, accounting for 46–88% of the total abundance and 68–99% of the
biomass. Oithona similis was the most abundant species in Yenisei Bay, being present with all age stages (including egg-carrying females). For the
first time, Oithona atlantica (CIII–CV copepodites, females and males) were found in the southeastern Kara Sea. In the southern part, Copepoda nauplii
prevailed in terms of total abundance while the mesozooplankton in the northwestern part was entirely dominated by older stages
of Pseudocalanus minutus. The mesozooplankton structure appears to be determined by available food resources and increased water temperature due to
a strong influence of warm Atlantic waters. 相似文献
8.
E. A. Pakhomov H. M. Verheye A. Atkinson R. K. Laubscher J. Taunton-Clark 《Polar Biology》1997,18(3):180-192
Mesozooplankton abundance, community structure and grazing impact were determined during late austral summer (February/March)
1994 at eight oceanic stations near South Georgia using samples collected with a Bongo and WP-2 nets in the upper 200-m and
100-m layer, respectively. The zooplankton abundance was generally dominated by copepodite stages C3–C5 of six copepod species:
Rhincalanus gigas, Calanus simillimus, Calanoides acutus, Metridia spp., Clausocalanus laticeps and Ctenocalanus vanus. Most copepods had large lipid sacs. All copepods accounted for 41–98% of total zooplankton abundance. Juvenile euphausiids
were the second most important component contributing between 1 and 20% of total abundance. Pteropods, mainly Limacina inflata, were important members of the pelagic community at two sites, accounting for 44 and 53% of total abundance. Average mesozooplankton
biomass in the upper 200 m was 8.0 g dry weight m−2, ranging from 4.3 to 11.5 g dry weight m−2. With the exception of Calanussimillimus, gut pigment contents and feeding activity of copepod species were low, suggesting that some species, after having stored
large lipid reserves, had probably started undergoing developmental arrest. Daily mesozooplankton grazing impact, measured
using in situ gut fluorescence techniques and in vitro incubations, varied widely from <1 to 8% (mean 3.5%) of phytoplankton
standing stock, and from 5 to 102% (mean 36%) of primary production. The highest grazing impact was found northeast of the
island co-incident with the lowest phytoplankton biomass and primary production levels.
Received: 30 October 1996 / Accepted: 23 February 1997 相似文献
9.
Margarita Elena Rentería-Cano Laura Sánchez-Velasco Evgueni Shumilin Miguel F. Lavín Jaime Gómez-Gutiérrez 《Biological trace element research》2011,142(3):848-864
We report the distribution of major and trace element concentrations in epipelagic zooplankton collected in the Northern Gulf
of California in August 2003. The Bray–Curtis index defined three element assemblages in zooplankton: (1) major metals, which
included only two elements, Na (3.6–17.0%) and Ca (1.0–4.8%). Na had its highest concentrations in the shallow tidally mixed
Upper Gulf, where high salinity, temperature, and zooplankton biomass (dominated by copepods) prevailed. Ca showed its highest
concentrations south of Ballenas Channel, characterized by tidal mixing and convergence-induced upwelling, indicated by low
sea-surface temperature, salinity, and zooplankton biomass; (2) Six biological essential elements, like Fe (80–9,100 mg kg−1) and Zn (20–2,570 mg kg−1), were detected in high concentrations in zooplankton collected near Guaymas Basin, which had high surface temperature and
chlorophyll a concentrations. (3) Metals of terrigenous origin, such as Sc (0.01–1.4 mg kg−1) and Th (0.03–2.3 mg kg−1), and redox-sensitive metals, like Co (3–23.8 mg kg−1); this was the assemblage with the largest number of elements (15). Both types of elements of assemblage 3 had maximum concentrations
in the cyclonic eddy that dominates the summer circulation in the Northern region. We concluded that sediment resuspension
by tidal mixing in the Upper Gulf, upwelling south of Ballenas Channel, and the cyclonic eddy were key oceanographic features
that affected the element concentrations of epipelagic zooplankton in the Northern Gulf of California. Oceanographic mechanisms
such as these may contribute to element incorporation in marine organisms in other seas. 相似文献
10.
Claudia Costa Bonecker Mariza Yuri Nagae Martin Cesar Maria Bletller Luiz Felipe Machado Velho Fábio Amodêo Lansac-Tôha 《Hydrobiologia》2007,579(1):115-123
In order to test the hypothesis that zooplankton biomass distribution (total and taxonomic groups) was influenced by the nutrient
concentration and primary productivity distribution in three tropical reservoirs, subsurface samples were taken in the fluvial,
transitional and lacustrine regions of three reservoirs (oligotrophic, mesotrophic and eutrophic) in southern Brazil (Paraná
State) in March and September 2002. Zooplankton biomass ranged from 0.04 to 264.47 mg DW m−3. Higher biomass values were observed for cladocerans (73.60%; 0.01–259.86 mg DW m−3), followed by copepods (22.05%; 0.01–69.69 mg DW m−3) and rotifers (4.35%; 0.01–11.52 mg DW m−3). In general, the total zooplankton, rotifer, cladoceran and copepod biomass, and chlorophyll-a and total nutrient concentrations showed a similar longitudinal distribution within the reservoirs. Total zooplankton, rotifer
and cladoceran biomass were related to the chlorophyll-a concentration, and zooplankton biomass was related to the total phosphorus distribution. This may have been due to the significant
multicolinearity between the chlorophyll-a and total phosphorus concentrations. Cyanobacteria influenced the taxonomic group biomass results by interfering with the
filter feeding in larger zooplankton species, which favoured the dominance of smaller species. As regards the longitudinal
distribution of copepod biomass, cyanobacteria biomass determined the displacement of the microcrustaceans to the fluvial
region of Iraí Reservoir. Our results supported the hypothesis formulated and the primary productivity was the major predictor
of the zooplankton biomass distribution in the reservoirs.
Handling editor: S. Dodson 相似文献
11.
S. V. Aleksandrov N. N. Zhigalova A. S. Zezera 《Russian Journal of Marine Biology》2009,35(4):296-304
Long-term research in the Baltic Sea revealed the basic trends of zooplankton community variations depending on oceanographic
processes. Alternation of the periods of increase and decrease in salinity of the Baltic Sea against the background of climate
changes (temperature increase) and eutrophication affect the state of the entire Baltic ecosystem, including zooplankton.
For these periods, the dynamics of zooplankton in the Baltic Sea were analyzed based on literature data and results of regular
research in the southeastern Baltic Sea during 1998–2007. The changes in the hydrological situation were accompanied by significant
changes in the zooplankton community. In the 1990s–2000s, the abundance and biomass of brackish-water and thermophilous species
primarily of Cladocera and Copepoda increased markedly. The role of the previously dominant marine copepod Pseudocalanus elongatus decreased due to salinity reduction in the deep-water part of the Baltic Sea. Maximum development of zooplankton occurred
in years of the greatest warming-up of the water (2001, 2005–2007) against the background of a general positive trend of zooplankton
abundance in the last decade. 相似文献
12.
The mesozooplankton of the northern White Sea and Mezen Bay was investigated at nine stations in July 2008 using a Juday net
(168 μm mesh size). A total of 39 taxa (species and higher taxa) were found in the samples. Average abundance, biomass, and
diversity (Shannon index) were (±SE) 120,793 ± 70,439 ind. m−2, 443 ± 216 mg DW m−2, and 1.41 ± 0.11, respectively. Copepods were most numerous. Overall, herbivores dominated primarily Cirripedia nauplii and
Pseudocalanus minutus. Significant correlations were observed among mean temperature, salinity, and mean mesozooplankton abundance and biomass.
Our data suggest that salinity and intensive local currents could be the main factors responsible for the distribution of
mesozooplankton in the northern White Sea. The average mesozooplankton biomass was higher than in previous studies, indicating
a possible climatic impact on the mesozooplankton community. 相似文献
13.
Crustacean zooplankton data were compiled from long-term observational studies at seven large shallow Florida lakes, to determine
whether there are general characteristics in regard to species composition, body size, and biomass. In particular, we examined
whether patterns in body size and species richness fit empirical models developed by Stanley Dodson. The lakes included range
in size from 125 to 1730 km2 and encompass mesotrophic to hyper-eutrophic conditions. We found that zooplankton biomass was strongly dominated by one
species of calanoid copepod—Arctodiaptomus dorsalis. Large daphnids were absent, and Cladocera assemblages were dominated by small taxa such as Ceriodaphnia, Chydorus, and Eubosmina. The total number of species of pelagic cladocerans (8–12) was consistent with Dodson’s predictions based on lake area. The
average size of crustacean zooplankton in Florida lakes is small in comparison with temperate communities. A. dorsalis is the smallest calanoid copepod in North America, and the mean length of Cladocera (0.6 mm) is consistent with Dodson’s
results that size decreases from temperate to tropical zones. Total biomass of crustacean zooplankton was very low, ratios
of zooplankton to phytoplankton biomass (0.01–0.1) are among the lowest reported in the literature, and the zooplankton displayed
short-lasting early spring peaks in biomass. Cladocera were almost entirely absent in spring and summer. Factors known to
occur in Florida lakes, which appear to explain these characteristics of biomass, include intense fish predation and high
summer water temperature. 相似文献
14.
Zooplankton composition and diversity in western Bay of Bengal 总被引:1,自引:0,他引:1
Nair S.R.Sreekumaran; Nair Vijayalakshmi R.; Achuthankutty C.T.; Madhupratap M. 《Journal of plankton research》1981,3(4):493-508
The biomass of zooplankton ranged from 1 90 ml/100 m3in the western Bay of Bengal from off Sri Lanka to south ofCalcutta in June 1978. The coastal belt between Madras and Visakhapatnamwhere upwdling is known to occur during the season showed higherstanding stock. Copepoda formed the dominant group followedby Decapod a and Chaetognatha. Species composition of variousgroups and their distribution is discussed. A general inverserelationship between biomass and species diversity was the trend.Diversity was higher in the oceanic realm. 相似文献
15.
Regional variations in mesozooplankton composition, abundance and biomass were studied during a cruise in August 2006 near
Novaya Zemlya Archipelago (eastern Barents Sea) using Juday net hauls from the bottom (or 100 m depth) to the surface. A comparison
with multiannual literature values revealed that the mean temperature and salinity in the south and centre of the study area
were similar to typical values, while temperature in the north was significantly higher. A total of 36 species and higher
taxa were identified. Mesozooplankton abundance and biomass varied from 47 to 851 ind m−3 and from 5 to 74 mg dry weight m−3, respectively. Copepods dominated the mesozooplankton community, reaching 73–98% and 61–97% of the total abundance and biomass.
Calanus finmarchicus and Oithona similis were the most abundant species at all stations. The biodiversities (Shannon indices) of the mesozooplankton community varied
between stations from 1.10 to 2.46 (estimated from species abundances) and from 0.19 to 1.92 (estimated from species biomasses),
averaging 1.93 ± 0.127 and 1.34 ± 0.151, respectively. Three groups at the 48% level of dissimilarity of species abundance
were delineated by cluster analyses. The clusters differed significantly with respect to temperature and salinity. The total
mesozooplankton abundance and biomass as well as quantitative parameters of most common taxa scaled negatively with temperature. 相似文献
16.
The feeding dynamics and predation impact of the hyperiid amphipod, Themisto gaudichaudi, on the zooplankton community in the waters surrounding the Prince Edward Archipelago were investigated at 30 stations in
late austral summer (April/May) 1998. Ingestion rates of T. gaudichaudi were estimated using two approaches, the gut fullness index and in vitro incubations. Throughout the investigation mesozooplankton,
comprising copepods, pteropods and chaetognaths, numerically and by biomass dominated Bongo samples. Zooplankton abundances
and biomass ranged from 8 to 271 ind. m−3 and between 1.01 and 7.47 mg dwt m−3, respectively. Densities of T. gaudichaudi during the study were low, never exceeding 0.4 ind. m−3. Gut content analysis (n=61) indicates that T. gaudichaudi is a non-selective, opportunistic carnivore generally feeding on the most abundant copepod and chaetognath species. Peaks
in feeding activity were recorded at sunrise and sunset, corresponding to their diel vertical migration patterns. Daily rations
estimated from in vitro incubations and gut fullness index were equivalent to 1.2–8.7% and between 11.5 and 19.8% of body
dry weight, respectively. The predation impact of T. gaudichaudi averaged over the upper 300 m of the water column was low, accounting for <0.4% of the mesozooplankton biomass or <3% of
the mesozooplankton secondary production. Indeed, the predation impact is likely to be lower as the contribution of the smaller
copepods (e.g. Oithona spp.) to total zooplankton was underestimated due to the sampling gear employed. The low predation impact recorded during
this study can be related to low abundances of T. gaudichaudi. It is likely that the importance of T. gaudichaudi as a secondary production consumer in the waters surrounding the Prince Edward Archipelago demonstrates a high degree of
spatio-temporal variability.
Accepted: 6 December 1999 相似文献
17.
Spring zooplankton distribution in the Bay of Biscay from 1998 to 2006 in relation with anchovy recruitment
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Irigoien Xabier; Fernandes Jose Antonio; Grosjean Philippe; Denis Kevin; Albaina Aitor; Santos Maria 《Journal of plankton research》2009,31(1):1-17
The objective of this study was to investigate whether successiverecruitment failures in the anchovy fishery in the Bay of Biscaywere due to changes in the zooplankton biomass or composition.Image analysis and automatic recognition were used to analysezooplankton samples collected during diel egg production methodspring surveys from 1998 to 2006. We were not able to detectany trend in zooplankton biomass during this period. The zooplanktonspatial distribution showed permanent features with large organismsbeing more abundant over the shelf break and outer areas. Finally,we found a negative correlation between anchovy recruitmentand zooplankton biomass which suggests that the 2002–2006failures in anchovy recruitment in the Bay of Biscay are notdue to a decrease in mesozooplankton biomass. 相似文献
18.
《农业工程》2014,34(3):141-147
Qinzhou Bay, the biggest bay in Guangxi Province, is very species-rich and is developing a robust marine economy. In recent years, as human impact has increased, problems associated with the environment have become more complicated. Measuring zooplankton diversity and abundance is a way to monitor environmental conditions. According to the data from four ecological surveys of the zooplankton in Qinzhou Bay during 2008 and 2009, a total of 134 species of zooplankton were identified, including 52 Copepoda species, 27 Medusa species, 14 Planktonic larvae, 9 Chaetognatha species, 8 Pteropoda species, 5 Amphipoda species, 4 Cladocera species, 4 Ostracoda species, 3 Thaliacea species, 2 Appendiculata species, 2 Sergestdae species, 2 Protlsta species, 1 Rotiera species and 1 Cumacea species. The fauna was clearly characterized as tropical population. The total species number was highest in autumn, followed by spring, winter and summer. Zooplankton species diversity in Qinzhou Bay has increased compared with the results obtained in 1983–1985 (83 species). However, compared with other bays, the number of zooplankton species in Qinzhou Bay is close to Daya Bay (128), higher than in Zhilin Bay (60), Jiaozhou Bay (81) and Luoyuan Bay (70), and far lower than in the north South Sea (709). We adopted the dominant index Y > 0.02 as the distinguishing standard of dominant species. The number of dominant species in spring, summer, autumn and winter were six, nine, eight and five. There was only one common dominant species (Penilia avirostris) appeared in different seasons, For summer and autumn, the shared dominant species numbered about four. Between other seasons, the shared dominant species varied between two and three. The number of uniquely dominant species was four in summer, three in autumn and one in both spring and winter. The dominant species in different seasons have some overlaps and some differences. The average biomass of zooplankton was 378 mg/m3 at all times of year. The average biomass was largest in autumn, followed by winter, and was the least in spring and summer. The average density of zooplankton for the entire year was 805.11 ind/m3. The average density was largest in summer, followed by winter, and was least in autumn and spring. Copepoda and Planktonic larvae were the major components of zooplankton in spring and summer at Qinzhou Bay, with the other species’ densities under 10%. In autumn, Copepoda, Planktonic larvae and Chaetognatha were the major components of the biomass, and in winter, the major species were Copepoda and Cladocera, with the others species’ density under 10%. The average value of the Shannon–Wiener diversity index (H′) was 3.84 and the evenness index (J′) was 0.77. The zooplankton diversity index and community evenness overall were good and the community organization had a complete and stable state, but the status of the community was relatively weak. The relationship between biomass/density of zooplankton and environmental factors is remarkable. Biomass and density are positively correlated with temperature and nutrient concentration, and are negatively correlated with salinity. 相似文献
19.
Weekly measurements of mesozooplankton (>76 μm) and hydrographic parameters have been carried out since 1984 in the List Tidal
Basin (northern Wadden Sea). Monthly water temperature significantly increased by 0.04°C year−1. The largest increase by 3°C in 22 years occurred in September, implying an extension of the warm summer period. Mean annual
copepod abundance and length of copepod season correlated significantly with mean temperature from January to May. Except
for an increasing Acartia sp. abundance during spring (April–May), no long-term trends in copepod abundance were observed. The percentage of carnivorous
zooplankton increased significantly since 1984 mainly due to a sudden increase in the cyclopoid copepod Oithona
similis in 1997. We expect that global warming will lead to a longer copepod season and higher copepod abundances in the northern
Wadden Sea. 相似文献
20.
Liu Zhensheng Wang Chunsheng Zhang Zhinan Cai Yuming Zhang Dongsheng 《Frontiers of Biology in China》2006,1(4):434-442
The species composition, biomass, abundance, and species diversity of zooplankton were determined for samples collected from
August 2002 to May 2003 from 14 stations in Yueqing Bay, China. Phytoplankton growth rate and microzooplankton grazing rate
were obtained by using the dilution method developed by Landry and Hassett. The spatial and temporal variations of zooplankton
and its relationship with environmental factors were also analyzed. The results showed that the zooplankton in the Yueqing
Bay could be divided into four ecotypes, namely coastal low saline species, estuary brackish water species, offshore warm
water species, and eurytopic species. A total of 75 species of zooplankton belonging to 56 genera and 17 groups of pelagic
larva were identified in the Yueqing Bay. The coastal low saline species was the dominant ecotype in the study area, and the
dominant species were Labidocera euchaeta, Acartia pacifica, Acrocalanus gibber, Pseudeuphausia sinica, and Sagitta bedoti among others.
There was considerable seasonal variation in zooplankton biomass and abundance in the surveyed areas. The peak biomass appeared
in August, descending in November and in May, and the lowest biomass appeared in February. Similarly, the highest abundance
of zooplankton was observed in August, with the abundance descending in the following months: May, November, and February.
There were similar horizontal distribution patterns for the biomass and the abundance of zooplankton. They both increased
from the upper to the lower bay in February and May, but decreased from the upper to the lower bay in August. Biomass and
abundance were evenly distributed in the Yueqing Bay in November. Moreover, there was marked seasonal variation in the species
diversity of zooplankton, which conformed to the abundance of zooplankton. Results of the dilution experiments indicated that
there was grazing pressure of microzooplankton on phytoplankton in the Yueqing Bay throughout the year though the rate of
microzooplankton grazing on phytoplankton varied seasonally. Phytoplanktons were growing at 0.26–2.07/d and grazed by microzooplankton
at a rate of 0.15–0.48/d in different seasons.
__________
Translated from Acta Ecologica Sinica, 2005, 25(8): 1853–1862 [译自: 生态学报, 2005, 25(8): 1853–1862] 相似文献