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1.
Primary productivity in the East China Sea and its adjacent area was measured by the13C tracer method during winter, summer and fall in 1993 and 1994. The depth-integrated primary productivity in the Kuroshio Current ranged from 220 to 350 mgC m−2d−1, and showed little seasonal variability. High primary productivity (above 570 mgC m−2d−1) was measured at the center of the continental shelf throughout the observation period. The productivity at the station nearest to the Changjiang estuary exhibited a distinctive seasonal change from 68 to 1,500 mgC m−2d−1. Depth-integrated primary productivity was 2.7 times higher in the shelf area than the rates at the Kuroshio Current. High chlorophyll-a specific productivity (mgC mgChl.-a−2d−1) throughout the euphotic zone was mainly found in the shelf area rather than off-shelf area, probably due to higher nutrient availability and higher activity of phytoplankton at the subsurface layer in the shelf area.  相似文献   

2.
As a part of the JGOFS synthesis and modeling project, researchers have been working to synthesize the WOCE/JGOFS/DOE/NOAA global CO2 survey data to better understand carbon cycling processes in the oceans. Working with international investigators we have compiled a Pacific Ocean data set with over 35,000 unique samples analyzed for at least two carbon species, oxygen, nutrients, chlorofluorocarbon (CFC) tracers, and hydrographic parameters. We use these data here to estimate in-situ oxygen utilization rates (OUR) and organic carbon remineralization rates within the upper water column of the Pacific Ocean. OURs are derived from the observed apparent oxygen utilization (AOU) and the water age estimates based on CFCs in the upper water and natural radiocarbon in deep waters. The rates are generally highest just below the euphotic zone and decrease with depth to values that are much lower and nearly constant in water deeper than 1200 m. OURs ranged from about 0.02–10 μmol kg−1yr−1 in the upper water masses from about 100–1000 m, and averaged = 0.10 μmol kg−1yr−1 in deep waters below 1200 m. The OUR data can be used to directly estimate organic carbon remineralization rates using the C:O Redfield ratio given in Anderson and Sarmiento (1994). When these rates are integrated we obtain an estimate of 5.3 ± 1 Pg C yr−1 for the remineralization of organic carbon in the upper water column of the Pacific Ocean. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

3.
This study demonstrates reduced electron transfer system (ETS) activity of mixed copepods collected from 5,000 to 7,000 m depths [3.21 ± 1.25 μl O2 (mg protein)−1 h−1 at 10°C] as compared with mixed copepods from 0 to 200 m depths [5.93 ± 1.66 μl O2 (mg protein)−1 h−1 at 10°C] of the western subarctic Pacific. At the in situ temperature of 1.5°C, the 5,000–7,000 m ETS data, in terms of wet mass (WM)-specific respiration rates (R), is equivalent to [0.052 ± 0.021 μl O2 (mg WM)−1 h−1] which is similar to or greater than those reported for selected copepods or mixed mesozooplankton from <5,000 m depth by previous workers.  相似文献   

4.
This paper reports all available geochemical data on sediments and pore waters from the Xisha Trough on the northern continental margin of the South China Sea. The methane concentrations in marine sediments display a downhole increasing trend and their carbon isotopic compositions (δ 13C = −25 to −51‰) indicate a thermogenic origin. Pore water Cl− concentrations show a range from 537 to 730 mM, and the high Cl− samples also have higher concentrations of Br−, Na+, K+, and Mg2+, implying mixing between normal seawater and brine in the basin. The SO4 2− concentrations of pore waters vary from 19.9 to 36.8 mM, and show a downhole decreasing trend. Calculated SMI (sulfate-methane interfaces) depths and sulfate gradients are between 21 and 47 mbsf, and between −0.7 and −1.7 mM/m, respectively, which are similar to values in gas hydrate locations worldwide and suggest a high methane flux in the basin. Overall, the geochemical data, together with geological and geophysical evidence, such as the high sedimentation rates, high organic carbon contents, thick sediment piles, salt and mud diapirs, active faulting, abundant thermogenic gases, and occurrence of huge bottom simulating reflector (BSR), are suggestive of a favorable condition for occurrence of gas hydrates in this region.  相似文献   

5.
The biochemical effects of a cold-core eddy that was shed from the Kuroshio Current at the Luzon Strait bordering the South China Sea (SCS) were studied in late spring, a relatively unproductive season in the SCS. The extent of the eddy was determined by time-series images of SeaWiFS ocean color, AVHRR sea surface temperature, and TOPEX/Jason-1 sea surface height anomaly. Nutrient budgets, nitrate-based new production, primary production, and phytoplankton assemblages were compared between the eddy and its surrounding Kuroshio and SCS waters. The enhanced productivity in the eddy was comparable to wintertime productivity in the SCS basin, which is supported by upwelled subsurface nitrate under the prevailing Northeastern Monsoon. There were more Synechococcus, pico-eucaryotes, and diatoms, but less Trichodesmium in the surface water inside the eddy than outside. Prochlorococcus and Richelia intracellularis showed no spatial differences. Water column-integrated primary production (IPP) inside the eddy was 2–3 times that outside the eddy in the SCS (1.09 vs. 0.59 g C m−2d−1), as was nitrate-based new production (INP) (0.67 vs. 0.25 g C m−2d−1). INP in the eddy was 6 times that in the Kuroshio (0.12 g C m−2d−1). IPP and INP in the eddy were higher than the maximum production values ever measured in the SCS basin. Surface chlorophyll a concentration (0.40 mg m−3) in the eddy equaled the maximum concentration registered for the SCS basin and was higher than the wintertime average (0.29 ± 0.04 mg m−3). INP was 3.5 times as great and IPP was doubled in the eddy compared to the wintertime SCS basin. As cold core eddies form intermittently all year round as the Kuroshio invades the SCS, their effects on phytoplankton productivity and assemblages are likely to have important influences on the biogeochemical cycle of the region.  相似文献   

6.
A Geographic Information System (GIS)-aided flow-tracking technique was adopted to investigate nutrient exchange rates between specific benthic communities and overlying seawater in a fringing reef of Ishigaki Island, subtropical Northwestern Pacific. Net exchange rates of NO3 −, NO2 −, NH4 +, PO4 3−, Total-N and Total-P were estimated from concentration changes along the drogue trajectories, each of which was tracked by the Global Positioning System and plotted on a benthic map to determine the types of benthic habitat over which the drogue had passed. The observed nutrient exchange rates were compared between 5 typical benthic zones (branched-coral (B) and Heliopora communities (H), seaweed-reefrock zone (W), bare sand area (S), and seagrass meadow (G)). The dependence of nutrient exchange rates on nutrient concentrations, physical conditions and benthic characteristics was analyzed by multiple regression analysis with the aid of GIS. The spatial correlation between nutrient exchange rates and benthic characteristics was confirmed, especially for NO3 − and PO4 3−, which were usually absorbed in hydrographically upstream zones B and W and regenerated in downstream zones H and G. NO3 − uptake in zones B and W was concentration-dependent, and the uptake rate coefficient was estimated to be 0.58 and 0.67 m h−1, respectively. Both nutrient uptake in zone W and regeneration in zone H were enhanced in summer. The net regeneration ratio of NO3 −/PO4 3− in zone H in summer ranged 5.2 to 34 (mean, 17.4), which was somewhat higher than previously measured NO3 −/PO4 3− for sediment pore waters around this zone (1.1–8.5). Nutrient exchanges in zone S were relatively small, indicating semi-closed nutrient cycling at the sediment-water interface of this zone. NH4 + efflux from sediments was suggested in zone G. The data suggest that the spatial pattern of nutrient dynamics over the reef flat community was constrained by zonation of benthic biota, and that abiotic factors such as nutrient concentrations and flow rates, influenced nutrient exchange rates only in absorption-dominated communities such as zones B and W.  相似文献   

7.
To understand the processes transporting nitrate to the surface layer of the western and central equatorial Pacific, we measured the nitrogen isotopic ratio of nitrate (δ 15NO 3 − ), which is a very useful tracer of the source of nitrate, above 200 m depth in this region in December 1999. δ 15NO 3 − is higher (about 13.0‰) in the surface water than in the subsurface water (where it is about 6.5‰) due to isotopic fractionation during nitrate uptake by phytoplankton. The δ 15NO 3 − value has a roughly linear relationship with the natural logarithm of nitrate concentration (ln[NO 3 − ]). However, for values above 150 m depth, the intercept of this linear relationship varies with position from east to west. On the other hand, the data at 200 m depth at all observation stations are concentrated around a single point (ln[NO 3 − ] = 2.5 and δ 15NO 3 − = 6.5‰) and do not fit the linear relationships for the shallower values. To examine the meaning of the observed distributions of δ 15NO 3 − and nitrate concentration we developed a box model including nitrogen and nitrogen isotopic cycles. By reproducing the observed relationship between δ 15NO 3 − and nitrate concentration using this model we found that most nitrate is transported horizontally from the eastern equatorial Pacific. We also conducted case studies and investigated the effects of differences in pathways of nitrate transport on the distributions of δ 15NO 3 − and nitrate concentration. From these studies we concluded that the observed linear relationships between δ 15NO 3 − and ln[NO 3 − ], having a common slope around 6‰ but different intercepts at each station, are evidence of the significant horizontal transport of nitrate to the surface water in this area.  相似文献   

8.
Temporal changes in nitrogen isotopic composition (δ15N) of the NO3 − pool in the water column below the pycnocline in Ise Bay, Japan were investigated to evaluate the effect of nitrification on the change in the δ15N in the water column. The δ15N of NO3 − in the lower layers varied from −8.5‰ in May to +8.4‰ in July in response to the development of seasonal hypoxia and conversion from NH4 + to NO3 −. The significantly 15N-depleted NO3 − in May most likely arose from nitrification in the water column. The calculated apparent isotopic discrimination for water column nitrification (ɛnit = δ15Nsubstrate − δ15Nproduct) was 24.5‰, which lies within the range of previous laboratory-based estimates. Though prominent deficits of NO3 − from hypoxic bottom waters due to denitrification were revealed in July, the isotopic discrimination of denitrification in the sediments was low (ɛdenit = ∼1‰). δ15NNO3 in the hypoxic lower layer mainly reflects the isotopic effect of water column nitrification, given that water column nitrification is not directly linked with sedimentary denitrification and the effect of sedimentary denitrification on the change in δ15NNO3 is relatively small.  相似文献   

9.
The δ18O, δ13C and trace element composition of pearls collected from Ago Bay, Japan, were investigated in order to evaluate biomineralization in the cultured pearl oyster (Pinctada fucata martensii). The oxygen isotopic data suggest that the pearls were produced around 23–24°C, mainly in June to early July, which is consistent with their occurrence in the field. Therefore the pearls were produced under or close to isotopic equilibrium conditions, although they showed high calcification rates (higher than 0.2–1.0 g cm− 2yr−1) under which, for example, coral skeletons (calcification rate ∼0.28 g cm− 2yr−1) often show non-equilibrium isotope partitioning. The δ13C values were ∼− 2.9‰ lower than those calculated for offshore waters under equilibrium conditions. This may be due to low-δ13C bottom waters resulting from the degradation of organic matter (OM) or to a contribution of low-δ 13C food. In the latter case, a simple mass balance calculation gives a respiration component of 14%. Twelve trace elements of bulk pearl samples were classified into four groups on the basis of their enrichment/depletion patterns relative to seawater and inter-element relationships: group 1, Co, Cr, Pb; group 2, Ba, Cs, U; group 3, Cu, Sn, V, and group 4, Mn, Rb, Mo. Comparison with coral skeletons suggests that Ba and Mn (groups 2 and 4) were definitely much enriched in proteinaceous OM relative to aragonite crystals in pearls and that V (group 3) in pearls showed only slight enrichment in the organicrich layer. By contrast, the other elements showed small differences between both layers (enrichment factor of <3), suggesting that these elements occur largely in aragonite crystals.  相似文献   

10.
In order to determine quantitatively the reason for the high productivity in the Oyashio Region, which is the southwest part of the Pacific Subarctic Region, the annual-mean vertical circulation of nitrogen in the region was estimated from the vertical profiles of nitrate, dissolved oxygen and salinity, and sediment-trap data by adapting them to the balance equations. Estimates of the upwelling velocity (1.7×10−5cm sec−1) and the vertical diffusivity (2.1 cm2 sec−1) in the abyssal zone and the primary and secondary productivities (44 and 4 mgN m−2day−1, respectively) in the euphotic zone were close to those of previous works. The estimated vertical circulation of nitrogen strongly suggested that, since the divergence (5 mgN m−2day−1) is caused by the abyssal convergence (6 mgN m−2day−1) and the positive precipitation, the local new production (22 mgN m−2day−1) necessarily exceeds not only the sinking flux (10 mgN m−2day−1) itself but also the sum of the sinking flux and the downward diffusion of dissolved and particulate organic matter (7 mgN m−2day−1) produced probably in the euphotic zone. The important roles of the abyssal circulation, the winter convection, and the metabolic activity in the bathyal zone to support the high productivity in the euphotic zone were clarified quantitatively.  相似文献   

11.
We measured the ammonium excretion, phosphate excretion and respiration rates of the scyphomedusa Aurelia aurita from Ondo Strait, in the central part of the Inland Sea of Japan, at 28 and 20°C. The rates measured at 28°C were converted to those at 20°C using the Q10 values, i.e. 1.56, 1.57 and 2.80, for ammonium excretion, phosphate excretion and respiration rates, respectively. The composite relationships between metabolic rates and wet weight of a medusa (WW, g, range 11–1330 g) at 20°C were expressed by the following allometric equations. For ammonium excretion rate (N, μmoles N medusa−1d−1): N = 0.497WW 1.09, phosphate excretion rate (P, μmoles P medusa−1d−1): P = 0.453WW 0.84, and respiration rate (R, μmoles O2 medusa−1d−1): R = 96.9WW 1.06. Mean O:N ratios (i.e. atomic ratios of 16.9 and 11.0 at 28 and 20°C, respectively) indicated that the metabolism of A. aurita medusae was protein-dominated. These metabolic parameters enabled us to estimate the nitrogen and phosphorus regeneration rates of an A. aurita medusa population typical of early summer in the Ondo Strait (means of water temperature, medusa individual weight and population biomass: 20°C, 200 g WW and 50.8 g WW m−3, respectively). Regenerated nitrogen and phosphorus were equivalent to 10.0 and 21.6% of phytoplankton uptake rates, respectively, nearly twice that estimated for mesozooplankton, demonstrating that A. aurita medusae are key components of the plankton community, influencing the trophic and nutrient dynamics in the Ondo Strait during early summer.  相似文献   

12.
Seasonal variations in the picoplankton community were investigated from June 2002 to March 2004 within the photic zone of Sagami Bay, Japan. The study area was mostly dominated by coastal waters during the warm period (mixed layer water temperature ≥ 18°C). During the cold period (mixed layer water temperature ≤ 18°C), the water mass was characterized by low temperature and high saline waters indicative of the North Pacific Subtropical Mode Water (NPSTMW). Occasionally, a third type of water mass characterized by high temperature and low saline properties was observed, which could be evidence of the intrusion of warm Kuroshio waters. Synechococcus was the dominant picophytoplankton (5−28 × 1011 cells m−2) followed by Prochlorococcus (1−5 × 1011 cells m−2) and picoeukaryotes during the warm period. Heterotrophic bacteria dominated the picoplankton community throughout the year, especially in the warm period. During the Kuroshio Current advection, cyanobacterial abundance was high whereas that of picoeukaryotes and heterotrophic bacteria was low. During the cold period, homogeneously distributed, lower picophytoplankton cell densities were observed. The dominance of Synechococcus in the warm period reflects the importance of high temperature, low salinity and high Photosynthetically Active Radiation (PAR) on its distribution. Cyanobacterial and heterotrophic bacterial abundance showed a positive correlation with temperature. Prochlorococcus and picoeukaryotes showed a positive correlation with nutrients. Picoeukaryotes were the major contributors to the picophytoplankton carbon biomass. The annual picophytoplankton contribution to the photosynthetic biomass was 32 ± 4%. These observations suggest that the environmental conditions, combined with the seasonal variability in the source of the water mass, determines the community structure of picoplankton, which contributes substantially to the phytoplankton biomass and can play a very important role in the food web dynamics of Sagami Bay.  相似文献   

13.
大亚湾细菌生产力研究   总被引：10，自引：1，他引：10       下载免费PDF全文
采用3H-胸腺嘧啶核苷示踪法测定了大亚湾的细菌生产力,结果表明,该海区的细菌生产力(C)的变化范围为0.50×10-3～30.2×10-3mg/(dm3·h),和其他海区的比较说明,在采样期间,大亚湾海域的细菌生产力是较高的,并对细菌生产力的空间分布以及相关生物、化学要素之间的相互关系进行了讨论。  相似文献   

14.
We deployed a profiling buoy system incorporating a fast repetition rate fluorometer in the western subarctic Pacific and carried out time-series observations of phytoplankton productivity from 9 June to 15 July 2006. The chlorophyll a (Chl a) biomass integrated over the euphotic layer was as high as 45–50 mg Chl a m−2 in the middle of June and remained in the 30–40 mg Chl a m−2 range during the rest of observation period; day-to-day variation in Chl a biomass was relatively small. The daily net primary productivity integrated over the euphotic layer ranged from 144 to 919 mg C m−2 day−1 and varied greatly, depending more on insolation rather than Chl a biomass. In addition, we found that part of primary production was exported to a 150-m depth within 2 days, indicating that the variations in primary productivity quickly influenced the organic carbon flux from the upper ocean. Our results suggest that the short-term variability in primary productivity is one of the key factors controlling the carbon cycle in the surface ocean in the western subarctic Pacific.  相似文献   

15.
Vibrio parahaemolyticus is a common pathogenic bacterium in marine and estuarine waters. To investigate interactions between V. parahaemolyticus and co-occurring redtide dinoflagellates, we monitored the daily abundance of 5 common red tide dinoflagellates in laboratory culture; Amphidinium carterae, Cochlodinium ploykrikoides, Gymnodinium impudicum, Prorocentrum micans, and P. minimum. Additionally, we measured the ingestion rate of each dinoflagellate on V. parahaemolyticus as a function of prey concentration. Each of the dinoflagellates responded differently to the abundance of V. parahaemolyticus. The abundances of A. carterae and P. micans were not lowered by V. parahaemolyticus, whereas that of C. polykrikodes was lowered considerably. The harmful effect depended on bacterial concentration and incubation time. Most C. polykrikoides cells died after 1 hour incubation when the V. parahaemolyticus concentration was 1.4×107 cells ml−1, while cells died within 2 days of incubation when the bacterial concentration was 1.5×106 cells ml−1. With increasing V. parahaemolyticus concentration, ingestion rates of P. micans, P. minimum, and A. carterae on the prey increased, whereas that on C. polykrikoides decreased. The maximum or highest ingestion rates of P. micans, P. minimum, and A. carterae on V. parahaemolyticus were 55, 5, and 2 cells alga−1 h−1, respectively. The results of the present study suggest that V. parahaemolyticus can be both the killer and prey for some red tide dinoflagellates.  相似文献   

16.
An analysis is presented of data on chlorophyll a concentrations of the total and the netplankton (>10 μm), determined either in April to June or in August to September from 48°N to 15°S along 175°E in the Pacific Ocean during 6 years by the NOPACCS (Northwest Pacific Carbon Cycle Study). Particular attention was given to the variability of absolute concentrations of the netplankton chlorophyll a and their percentage shares of the total chlorophyll a concentration. Below 0.2 μg l−1 of surface total chlorophyll a, the netplankton chlorophyll a showed low percentage shares (such as 12.7% on average) with a large variation, but above 0.2 μg l−1 it was 35.9% on average with less variation, showing an accelerated increase at high total chlorophyll a concentrations. High netplankton chlorophyll a concentrations in surface waters were observed at high latitudes, in waters having high chlorophyll a concentrations at sub-surface depth, and in equatorial upwelling. The percentage shares of netplankton in the total chlorophyll a in the euphotic zone were 8.5% and 25.9% above and below 0.2 μg l−1, respectively, although the data points scattered over a wide range (from 7.2% to 53.8%) depending on differences in water masses, depths and seasons. High chlorophyll a concentrations and high percentage shares of netplankton corresponded to high ambient nitrate plus nitrite concentrations. Integrated netplankton chlorophyll a concentrations in the euphotic zone varied from 0.7 to 19.5 mg m−2 in waters below 0.2 μg l−1 of surface total chlorophyll a, and from 2.0 to 29.5 mg m−2 above 0.2 μg l−1, and the percentage shares of netplankton for the former were 7.4% on average and 23.7% for the latter. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

17.
Temperature is thought to have a disproportionate role in controlling bacterial growth in perennially cold waters like the Western Arctic Ocean. One impact of temperature is that bacteria in cold waters may require more dissolved organic material (DOM) in order to approach growth rates observed at higher temperatures (the Wiebe–Pomeroy hypothesis). To explore these issues, this study examined the effect of DOM additions and temperatures shifts on bacterial assemblages during short (2 h) and long (up to 10 days) incubations. We found that the temperature response for bacterial assemblages in the Western Arctic was similar to that observed in temperate waters; the Q10 values for leucine and thymidine incorporation were 3.1±2.6 and 1.9±0.56, respectively, not significantly different from values observed in the equatorial Pacific Ocean. In contrast to what would be predicted from the Wiebe–Pomeroy hypothesis, the impact of DOM additions on leucine incorporation either was the same or greater at higher, not lower temperatures. Increasing the incubation temperature did stimulate leucine incorporation more quickly than did DOM additions, but DOM seems as important as temperature in controlling bacterial growth. Leucine incorporation rates per cell (an index of community growth rates) observed in these experiments varied greatly and approached rates observed in waters warmer by 25 °C. These results suggest that the role of temperature in controlling bacterial growth in the Western Arctic is similar to that in low-latitude ocean.  相似文献   

18.
The light-saturated maximum value (P B max) and initial slope (α) of the photosynthesis-irradiance (P-E) curve were examined in a warm streamer, a cold streamer and a warm core ring off the Sanriku area in the subarctic western North Pacific Ocean during an ADEOS/OCTS Sanriku field campaign in early May 1997. BothP B max and α were within the ranges of temperate populations. A regional difference was apparent inP B max: populations in the warm streamer tended to show higher value ranging between 1.92 and 4.74 mgC (mgChla)−1h−1 than those in the cold streamer and the warm core ring (1.35–2.87 mgC (mgChla)−1h−1). A depth variation was also observed in α in both the warm streamer and the warm core ring: shallow populations tended to have lower α than deep populations. The depth variations in bothP B max and α resulted in a lower light intensity of the light saturation in a deeper population than that of a shallower one. These depth-related variations in the P-E parameters were likely a manifestation of “shade-adaptation” of photosynthesis. Photoinhibition was not observed over in situ surface light intensity varying below ca 1600 μmol photon m−2s−1. Water-column primary productivity was biooptically estimated to be 233 to 949 mgC m−2d−1 using vertical distributions of the P-E parameters, chlorophylla, phytoplankton light absorption and underwater irradiance. Applicability of surface data sets for estimation of water-column productivity is discussed.  相似文献   

19.
Observations of primary productivity, 234Th, and particulate organic carbon (POC) were made from west to east across the northern North Pacific Ocean (from station K2 to Ocean Station Papa) during September–October 2005. Primary productivities in this region varied longitudinally from approximately 236 to 444 mgC m−2d−1 and clearly indicate the West High East Low (WHEL) trend. We estimated east-west variations in the POC flux from the surface layer (0–100 m) by using 234Th as a tracer. POC fluxes in the western region (44–53 mgC m−2d−1) were higher than those in the eastern region (21–34 mgC m−2d−1). However, the export ratios (e-ratios) ranged from approximately 8% to 16% and did not show the WHEL trend. Contrary to our expectation, no relation between POC flux (or e-ratio) and diatom biomass (or dominance) was apparent in autumn in the northern North Pacific.  相似文献   

20.
The egg production rate (EPR) of Calanus sinicus was measured from March 2007 to April 2010 at three stations along the Korean coast of the Yellow Sea (in coastal waters off Saemangum, Yeongheungdo, and Asan Bay) to estimate in situ maximum egg production rate (MEPR) and to understand whether the females were limited in their growth or fecundity in the field. The mean EPR of C. sinicus at each sampling date ranged from 10.3–34.9 eggs female−1 d−1 (mean 23.4 eggs female−1 d−1), and the EPR of individual copepods ranged from 0–81 eggs female−1 d−1. The mean EPR was positively correlated with the body weight of female copepods. The MEPR at each sampling date ranged from 40–81 eggs female−1 d−1 (mean 50.4 eggs female−1 d−1). Over 84% of eggs spawned hatched successfully. The weight-specific growth rate (WSGR) ranged from 0.038–0.111 d−1 (mean 0.082 d−1), indicating that 3.8–11.1% of the carbon in an adult female was produced daily as female growth. The WSGR was negatively correlated with water temperature. The ratio of mean EPR to observed mean MEPR ranged from 20–70% (mean 46%), indicating that ∼54% of a female’s growth might be limited in the field. We suggest that the ratio of observed EPR to mean MEPR of copepod can be applied to understand how the copepod responds to environmental changes, as well as EPR and hatching success.  相似文献   

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