scholarly journals Laboratory experiments on the transfer dynamics of plutonium from marine sediments to sea water and to marine organisms

1975 ◽  
Author(s):  
T. Mo ◽  
F.G. Lowman
Keyword(s):  
Marine Sediments ◽  
Laboratory Experiments ◽  
Sea Water ◽  
Marine Organisms

Eco-Physiological Studies of an Intertidal Crustacean, Pollicipes Polymerus (Cirripedia, Lepadomorpha)

1972 ◽  
Vol 57 (1) ◽  
pp. 83-102
Author(s):  
H. J. FYHN ◽  
J. A. PETERSEN ◽  
K. JOHANSEN
Keyword(s):  
Water Loss ◽  
Volume Regulation ◽  
Free Amino ◽  
Heat Load ◽  
Laboratory Experiments ◽  
Sea Water ◽  
Physiological Responses ◽  
The Body ◽  
Air Exposure ◽  
Pollicipes Polymerus

1. Physiological responses to environmental stresses of the intertidal cirriped Pollicipes polymerus have been studied by combined field and laboratory experiments. 2. The body temperature of air-exposed animals is always lower than expected from the heat load. Evaporation from the peduncle is responsible for the heat loss. 3. The rate of water loss by evaporation from the peduncle cuticle is 1.5 µl/cm2 h mmHg both at 21 and 27 °C. The transpiration is proportional to the saturation deficit of the air. The water loss from the capitulum is negligible in comparison to that from the peduncle. 4. The haemolymph osmolality of animals in the field increases during exposure to sunshine and decreases during exposure to rain. The increase in haemolymph osmolality during desiccation is equal to that calculated from the decrease in body water. The water loss during air exposure is adequately replaced during submersion, probably by osmosis. 5. Pollicipes is an osmoconformer but is 5-20 m-osmoles hyperosmotic. It tolerates sea-water dilutions down to about 50%. The hyperosmolality seems to be balanced by a high internal hydrostatic pressure. 6. An excretory activity is observed. The excretion is isosmotic to the haemolymph and is possibly an ultrafiltrate of the latter. 7. The muscle cells show volume regulation, but free amino acids seem to be unimportant in regulation of intracellular osmolality. The concentration of ninhydrinpositive substances in the muscle tissue is about 200 mM for animals in full strength sea water.

scholarly journals Compound-Specific Radiocarbon Ages of Fatty Acids in Marine Sediments from the Western North Pacific

Radiocarbon ◽  
2001 ◽  
Vol 43 (2B) ◽  
pp. 949-956 ◽  
Author(s):  
Masao Uchida ◽  
Yasuyuki Shibata ◽  
Kimitaka Kawamura ◽  
Yuichiro Kumamoto ◽  
Minoru Yoneda ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Molecular Weight ◽  
Organic Matter ◽  
Marine Sediments ◽  
North Pacific ◽  
Western North Pacific ◽  
Higher Plants ◽  
Bimodal Distribution ◽  
Marine Organisms ◽  
Terrestrial Organic Matter

Compound-specific radiocarbon analysis of five fatty-acid biomarkers was conducted for marine sediments collected from the western North Pacific. The fatty acids (C12 to C34) showed a typical bimodal distribution pattern with two maxima at C16 and C26. Their carbon isotopic compositions ranged from −25.1‰ (C16) to −31.8‰ (C28), suggesting that they derived from terrestrial higher plants and marine organisms. A large variations of 14C ages were found among the fatty acids detected in the same sedimentary horizon of the core, ranging from 530 BP (C18) to 3250 BP (C28). The results of 14C analysis of fatty acids could be divided into two groups, i.e., lower molecular weight (LMW) fatty acids (C16, C18) derived from marine organisms and higher molecular weight (HMW) fatty acids (C24, C26, C28) derived from terrestrial higher plants. The HMW fatty acids showed older ages, ranging from 2550 BP (C24) to 3250 BP (C28), than LMW fatty acids (530 BP [C18] to 1,820 years BP [C16]). On the other hand, bulk-phase total organic matter (TOM) showed the age of 2260 BP that is between those two groups, suggesting that it was likely a mixture of organic matter derived from marine and terrestrial sources. The compound specific 14C ages and δ13C data of sedimentary fatty acids presented here could provide useful information to decipher the fate and transport process of terrestrial organic matter to marine sediments.

scholarly journals Inspection of the Laboratory.

1897 ◽  
Vol 5 (1) ◽  
pp. 98-99
Author(s):  
E. Ray Lankester ◽  
F. E. Beddard
Keyword(s):  
General Circulation ◽  
Sea Water ◽  
Marine Organisms ◽  
Committee Report ◽  
Lecture Room ◽  
Good Order

The Laboratory was visited and inspected on June 26th and 27th by a Committee appointed by the Council for that purpose, and the following report was submitted to the Council at the meeting held on June 29th:—“The Committee, consisting of the President and Mr. Beddard, arrived in Plymouth on Saturday, June 26th. They visited the laboratories, engine-rooms, tank-room, library, and museum on both Saturday and Sunday. By the President's invitation, they were joined at Plymouth by Mr. John Enys, of Enys, near Falmouth, a member of the Association.“The Committee report in the first place that the satisfactory standard of general efficiency noted last year has been fully maintained. The place is in excellent condition, clean and orderly, and the servants are well in hand.“The large laboratory has been provided with a new flat tank, eight feet by five feet and eight inches deep, by aid of which Mr. Garstang has been carrying on some observations on the habits of Brachyurous Crustacea. The sea-water supplied to the laboratory is still kept distinct from the general circulation in the show tanks, and is never returned to the laboratory tanks after it has passed through them. We are of opinion that this is the only satisfactory system for maintaining marine organisms in a really healthy condition in confinement, the whole theory of ‘circulation’ being illusory and in practice disastrous.“The lecture-room is in good order, and has proved to be very useful and well fitted for its purpose.“The collection of local types in the museum has progressed.

scholarly journals Experiments on some effects of certain environmental factors on Gracilaria verrucosa (Hudson) Papenfuss

1959 ◽  
Vol 38 (1) ◽  
pp. 153-167 ◽  
Author(s):  
W. Eifion Jones
Keyword(s):  
Growth Rate ◽  
Environmental Factors ◽  
High Intensity ◽  
Laboratory Experiments ◽  
Early Stage ◽  
Wave Action ◽  
Marine Organisms ◽  
Gracilaria Verrucosa ◽  
The Church

At an early stage of an autecological study of Gracilaria verrucosa (Hudson) Papenfuss it seemed possible that the best growth of the plants occurred in places, such as the Achill Sound and the Church Island Channel in the Menai Straits, where, in the absence of heavy wave action, strong currents flowed over the plants. Experiments were carried out, in the sea, to investigate the effect of currents on the growth rate; the apparatus used and described here would probably be suitable for the investigation of current effects on other sedentary marine organisms.These experiments also led to some observations on the effects of illumination on the pigmentation and growth rate of the plants which were supplemented by laboratory experiments. High intensity illumination in the laboratory also demonstrated positive phototropism in the plant.

scholarly journals Distribution of Radionuclides among Green Alga, Marine Sediments and Sea Water

1977 ◽  
Vol 18 (4) ◽  
pp. 322-330 ◽  
Author(s):  
R. NAKAMURA ◽  
Y. SUZUKI ◽  
T. UEDA
Keyword(s):  
Green Alga ◽  
Marine Sediments ◽  
Sea Water

scholarly journals The Formation of Brine Drainage Features in Young Sea Ice

1975 ◽  
Vol 14 (70) ◽  
pp. 137-154 ◽  
Author(s):  
Lars Ingolf Eide ◽  
Seelye Martin
Keyword(s):  
Sea Ice ◽  
Laboratory Experiments ◽  
Sea Water ◽  
Salt Water ◽  
Pressure Head ◽  
Drainage Channels ◽  
The Difference ◽  
Thin Plastic ◽  
Ice Water ◽  
Brine Channel

Laboratory experiments on the growth of sea ice in a very thin plastic tank filled with salt water, cooled from above and insulated with thermopane, clearly show the formation and development of brine drainage channels. The sea-water freezing cell is 0.3 cm thick by 35 cm wide by 50 cm deep; the thermopane insulation permits the ice interior to be photographed. Experimentally, we observe that vertical channels with diameters of 1 to 3 mm and associated smaller feeder channels extend throughout the ice sheet. Close examination of the brine channels show that their diameter at the ice-water interface is much narrower than higher up in the ice, so that the channel has a “neck” at the interface. Further, oscillations occur in the brine channels, in that brine flows out of the channel followed by a flow of sea-water up into the channel. Theoretically, a qualitative theory based on the difference in pressure head between the brine inside the ice and the sea-water provides a consistent explanation for the formation of the channels, and the onset of a convective instability explains the existence of the neck. Finally, an analysis based on the presence of the brine-channel neck provides an explanation for the observed oscillations.

scholarly journals Accumulation of 60Co by marine organisms under reduction of radioactivity in sea water.

1985 ◽  
Vol 51 (11) ◽  
pp. 1811-1816 ◽  
Author(s):  
Taishi UEDA ◽  
Motokazu NAKAHARA ◽  
Ryoichi NAKAMURA ◽  
Yuzuru SUZUKI
Keyword(s):  
Sea Water ◽  
Marine Organisms

Limited Arsenic Dispersion in Sea Water, Sediments, and Biota Near a Continuous Source

1975 ◽  
Vol 32 (8) ◽  
pp. 1275-1281 ◽  
Author(s):  
William R. Penrose ◽  
Robert Black ◽  
Michael J. Hayward
Keyword(s):  
Surface Water ◽  
Sea Urchin ◽  
Sea Water ◽  
Inorganic Arsenic ◽  
Marine Organisms ◽  
Strongylocentrotus Droebachiensis ◽  
Continuous Exposure ◽  
Total Arsenic ◽  
Mine Site ◽  
Continuous Source

Moreton’s Harbour, Newfoundland, has been exposed to arsenic-bearing drainage and leaching from a stibnite mine for at least 38 yr and possibly longer than 84 yr. Measurements of inorganic arsenic in sea water and sediments and total arsenic in some marine organisms revealed a very limited influence of continuous exposure to arsenic in the small harbor. Arsenic concentrations in surface water declined to normal within 200 m, and in sediments within 50 m. Animals did not show significantly higher levels nearer the mine, with the exception of the sea urchin Strongylocentrotus droebachiensis, which accumulated significantly higher levels of arsenic adjacent to the mine site.

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