13C and 15N Uptake by Phytoplankton in the Antarctic Upwelling Area: Results from the Antiprod I Cruise in the Indian Ocean Sector

1979 ◽  
Vol 30 (4) ◽  
pp. 431 ◽  
Author(s):  
G Slawyk
Keyword(s):  
Particulate Matter ◽  
Water Temperature ◽  
Growth Rates ◽  
Uptake Rate ◽  
Inorganic Carbon ◽  
Carbon And Nitrogen ◽  
15N Uptake ◽  
Total Irradiation ◽  
Specific Uptake ◽  
The Antarctic

13C and 15N uptake measurements were carried out in the Indian sector of the Antarctic Ocean along a 66�30'E. transect. Integrated values ranged from 0.41 to 1.00 and from 0.03 to 0.12 mg-atom m-2 h-1 for inorganic carbon and nitrogen respectively. These low values were in contrast to the high nutrient concentrations and the total irradiation available. Nitrate-nitrogen concentrations for example were mostly above 20�g-atom l-1 and on-deck total irradiation integrated over the entire incubation period was on average 10 MJ m-2. Integrated values for particulate matter varied between 337.5 and 694.4 mg-atom m-2 for carbon and between 48.2 and 92.2 mg-atom m-2 for nitrogen. Carbon to nitrogen composition ratios of the particulate matter have been compared with the uptake ratios of the same elements. While euphotic zone profiles of the former ratio exhibited only small changes (6.0-8.1, all stations included), corresponding uptake ratios varied over a wide range (0.1-25.1). Generally, the latter ratio decreased with decreasing available radiation. Response curves of specific uptake rate for carbon and nitrogen to increasing available radiation were found to be hyperbolic in shape and yielded half-saturation constants ranging between 0.9 and 3.9% of surface quantum irradiance, or between 4.9 and 16.2 × 1021 quanta m-2 h-1, if expressed in absolute units. Specific uptake rate for nitrate was directly related to ambient water temperature along a north-south cross section, but this relationship may have been an indirect one as other factors were possibly involved (ammonium concentration for example). Maximum growth rates as doublings per day expected from water temperature were about an order of magnitude higher than the measured actual specific uptake rates for inorganic carbon and nitrogen. This was also observed in a culture of natural phytoplankton. However, measured growth rates obtained from cell counts in the same culture agreed very well with the calculated maximum expected growth rates. Phytoplankton cells from the shipboard culture continued to divide while decreasing the nutrient cell content and without a corresponding increase in specific nutrient uptake rate. The lack of intensive nutrient utilization reflected the field situation and the limiting factor could not be identified in the culture or in the field.

Influence of Water Temperature on the Growth Rate of the Landlocked Sea Lamprey (Petromyzon marinus) and the Associated Rate of Host Mortality

1977 ◽  
Vol 34 (9) ◽  
pp. 1373-1378 ◽  
Author(s):  
G. J. Farmer ◽  
F. W. H. Beamish ◽  
P. F. Lett
Keyword(s):  
Growth Rate ◽  
Great Lakes ◽  
Water Temperature ◽  
Growth Rates ◽  
Petromyzon Marinus ◽  
Sea Lamprey ◽  
Instantaneous Growth ◽  
Exponential Decline ◽  
Influence Of Water ◽  
Host Mortality

Groups of sea lampreys (Petromyzon marinus) of 10–90 g initial weight were held at temperatures of 1–20 °C for 30 days and allowed to feed ad lib. on white suckers (Catostomus commersoni). Increases in water temperature and in lamprey size caused the rate of host mortality to increase in agreement with observations that mortality in the Great Lakes is seasonal. Instantaneous growth rates were maximal at 20 °C for lampreys of 10–30 g, the optimal temperature for growth shifting to 15 °C for larger lampreys of 30–90 g. Growth rates were intermediate at 10 °C and lowest at 4 °C for lampreys of all size. Accordingly, host mortality increased with temperature over the 4–20 °C range. At all experimental temperatures, increases in lamprey weight were accompanied by an exponential decline in instantaneous growth rates, a phenomenon also observed for teleosts. Laboratory growth rates at temperatures of 5–15 °C were comparable to rates observed for lampreys in Lake Huron between April and November and agree with the observation that lampreys feed in deeper waters between April and June before moving to warmer, shallower waters during the summer when growth rate increases. Key words: sea lamprey, white sucker, host, temperature, growth, Great Lakes, mortality

In situ growth rate estimates of Southern Ocean krill, Thysanoessa macrura

2019 ◽  
Vol 31 (3) ◽  
pp. 116-122 ◽  
Author(s):  
Jake R. Wallis ◽  
Jessica E. Melvin ◽  
Robert King ◽  
So Kawaguchi
Keyword(s):  
Growth Rate ◽  
Southern Ocean ◽  
Growth Rates ◽  
Somatic Growth ◽  
Growth Patterns ◽  
Daily Growth ◽  
Thysanoessa Macrura ◽  
Growth Method ◽  
Repeated Sampling ◽  
The Antarctic

AbstractGrowth, which is intrinsically linked to environmental conditions including temperature and food availability are highly variable both temporally and spatially. Estimates of growth rates of the Southern Ocean euphausiid Thysanoessa macrura are currently restricted to limited studies which rely upon repeated sampling and length-frequency analysis to quantify growth rates. The instantaneous growth method (IGR) was used to measure the growth rate of T. macrura successfully in the southern Kerulen Plateau region during summer, providing the first IGR parameters for the Southern Ocean euphausiid species. Results of the four-day IGR incubation indicate a period of low somatic growth for adult T. macrura. Males had a longer intermoult period (IMP) (62 days) than females (42 days), but the sexes exhibited similar daily growth rates of 0.011 mm day−1 and 0.012 mm day−1 respectively. Juveniles exhibited the fastest growth, with an IMP of 13 days and daily growth rate of 0.055 mm day−1 indicating a prolonged growth season, similar to the Antarctic krill E. superba. Consequently, we highlight the usability of the IGR method and strongly encourage its use in developing a comprehensive understanding of spatial and seasonal growth patterns of T. macrura.

scholarly journals The effects of water temperature on the juvenile performance of two tropical damselfishes expatriating to temperate reefs

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Lucas D. Djurichkovic ◽  
Jennifer M. Donelson ◽  
Ashley M. Fowler ◽  
David A. Feary ◽  
David J. Booth
Keyword(s):  
Water Temperature ◽  
Growth Rates ◽  
Global Climate ◽  
Austral Summer ◽  
Reef Fishes ◽  
Performance Parameters ◽  
Feeding Rates ◽  
Lower Growth ◽  
Temperate Reefs ◽  
Eastern Australia

Abstract Ocean warming associated with global climate change is already inducing geographic range shifts of marine species. Juvenile coral reef fishes transported into temperate latitudes (termed ‘vagrant’ fishes) can experience winter water temperatures below their normal thermal minimum. Such environmental extremes may increase energetic costs for such fishes, resulting in reduced performance, which may be the governing factor that limits the potential for poleward range expansion of such fishes. This study compared the juvenile physiological performance and behaviour of two congeneric tropical damselfishes which settle during austral summer months within temperate eastern Australia: Abudefduf vaigiensis have an extended southern range, and lower threshold survival temperature than the congeneric A. whitleyi. Physiological and behavioural performance parameters that may be affected by cooler temperature regimes at higher latitudes were measured in aquaria. Lower water temperature resulted in reduced growth rates, feeding rates, burst escape speed and metabolic rates of both species, with significantly reduced performance (up to six-fold reductions) for fishes reared at 18 °C relative to 22 °C and 26 °C. However, A. whitleyi exhibited lower growth rates than A. vaigiensis across all temperatures, and lower aerobic capacity at the lowest temperature (18 °C). This difference between species in growth and metabolic capacity suggests that the extended southern distribution and greater overwintering success of A. vaigiensis, in comparison to A. whitleyi is related to thermal performance parameters which are critical in maintaining individual health and survival. Our results support previous findings in the region that water temperature below 22 °C represents a critical physiological threshold for tropical Abudefduf species expatriating into temperate south-eastern Australia.

scholarly journals Growth and metabolism in the Antarctic brachiopod Liothyrella uva

1997 ◽  
Vol 352 (1355) ◽  
pp. 851-858 ◽  
Author(s):  
Lloyd S. Peck ◽  
Simon Brockington ◽  
Thomas Brey
Keyword(s):  
Growth Rates ◽  
Marine Invertebrates ◽  
Shell Growth ◽  
Growth Study ◽  
Tissue Mass ◽  
Phytoplankton Productivity ◽  
Main Period ◽  
The Difference ◽  
The Antarctic ◽  
Mass Increase

Summer and winter growth rates were assessed separately for a population of the Antarctic brachiopod Liothyrella uva between early January 1992 and December 1993. Annual shell growth rates (1.6–2.3 mm yr −1 for a 5 mm individual; 0.96–1.44 mm −1 for a 20 mm specimen) were two to six times slower than those reported for temperate species. Growth in specimens less than 20 mm in length was faster in 1992 than in 1993, although differences between years over the whole size range were not significant. Surprisingly, growth was much faster in winter periods than during the summers. A 5 mm long individual grew five times faster in winter than in summer, and for a 20 mm long specimen the difference was 13 times. This runs contrary to current ideas on the effects of seasonality on the biology of polar marine invertebrates, but may be an effect of maximizing the efficiency of resource utilization. Comparisons with previous work showed shell growth to be decoupled from periods of tissue mass increase, and also from the main period of phytoplankton productivity. Oxygen consumption of 75 of the specimens used in the growth study was measured to test the hypothesis that basal metabolic rates should be inversely correlated with growth rates. Unexpectedly, an analysis of residuals produced no significant relationship, positive or negative, between growth rate and basal metabolism ( F = 1.37, p =0.25, n = 75).

scholarly journals On the Linkage between Antarctic Surface Water Stratification and Global Deep-Water Temperature

2011 ◽  
Vol 24 (14) ◽  
pp. 3545-3557 ◽  
Author(s):  
Ralph F. Keeling ◽  
Martin Visbeck
Keyword(s):  
Water Temperature ◽  
North Atlantic ◽  
Deep Water ◽  
Surface Waters ◽  
Feedback Loop ◽  
Deep Ocean ◽  
Static Stability ◽  
Deep Waters ◽  
Water Stratification ◽  
The Antarctic

Abstract The suggestion is advanced that the remarkably low static stability of Antarctic surface waters may arise from a feedback loop involving global deep-water temperatures. If deep-water temperatures are too warm, this promotes Antarctic convection, thereby strengthening the inflow of Antarctic Bottom Water into the ocean interior and cooling the deep ocean. If deep waters are too cold, this promotes Antarctic stratification allowing the deep ocean to warm because of the input of North Atlantic Deep Water. A steady-state deep-water temperature is achieved such that the Antarctic surface can barely undergo convection. A two-box model is used to illustrate this feedback loop in its simplest expression and to develop basic concepts, such as the bounds on the operation of this loop. The model illustrates the possible dominating influence of Antarctic upwelling rate and Antarctic freshwater balance on global deep-water temperatures.

Physioecologic and Metabolic Properties of a Ayntrophic Acetogenesis Coculture

2013 ◽  
Vol 807-809 ◽  
pp. 1290-1293
Author(s):  
Tao Jiang ◽  
Jun Guo He ◽  
Xiang Guo Zeng ◽  
Jian Zheng Li
Keyword(s):  
Anaerobic Digestion ◽  
Nitrogen Source ◽  
Metabolic Activity ◽  
Uptake Rate ◽  
Anaerobic Metabolism ◽  
Batch Cultivation ◽  
Cultivation Temperature ◽  
Carbon And Nitrogen ◽  
Obligate Anaerobic ◽  
Metabolic Properties

In anaerobic digestion system, the functional niche of hydrogen-producing acetogens (HPAs) is between acidogenic fermentation bacteria and methanogens. HPAs are quite difficult to be isolated by pure and ampliative cultures due to the obligate anaerobic metabolism property in syntrophic association with methanogenic. In order to enhance the HPAs activities in anaerobic disgestion, the physioecologic and metabolic properties of HPAs under different medium conditions, such as carbon and nitrogen type, influent temperature and pH was investigated in batch cultivation experiments. The result illustrated that under the cultivation temperature of 45°C and pH of 8.0, the butyrate, propionate and benzoate could be utilized by the syntrophic acetogenesis coculture, of which the uptake rate of butyrate was highest. The glucose and sucrose were repulsed however. The metabolic activity of HPAs could be enormously simulated as the mixture of tryptone and yeast was taken as the nitrogen source.

Sign in / Sign up

Export Citation Format

Share Document