Studies on elemental and energy transfer in lower trophic levels in
the marine environment were initiated in July 1962 after receipt of AEC
contract AT(45-1)1751. It should be pointed out that this report covers
only a six-month period, because for bookkeeping purposes the contract
was made retroactive to 1 April 1962, at the request of the contractor

Curl, Herbert Charles

Small, Lawrence Frederick

Undetermined

ScholarsArchive@OSU

arS-cG85b:0135'no U3 2cop ___I14 "i33lRTMENT of OCEANOGRAPHYNENALEM R.TILLAMOOK BAY"SCHOOL of SCIENCEOREGON STATE UNIVERSITYEnergy Conversionand Element TransferIn Lower Trophic LevelsIn the Marine EnvironmentbyLawrence F. Small and Herbert Curl, Jr.AEC Progress Report Reference 63-2April-December 1962 January 1963ENERGY CONVERSION AND ELEMENT TRANSFER INLOWER TROPHIC LEVELS IN THE MARINE ENVIRONMENTbyLawrence F. SmallandHerbert Curl, Jr.Department of OceanographyOregon State UniversityProgress Report1 April through 31 December 1962Submitted to theU. S. Atomic Energy Commissionunder Contract AT(45-1)1751.Approved: Reproduction in whole orin part is permitted forany purpose of the UnitedStates Government.Wayne X Burt, Chairman Reference 63-2Coe ),rnDepartment of Oceanography January 1963ENERGY CONVERSION AND ELEMENT TRANSFER INLOWER TROPHIC LEVELS IN THE MARINE ENVIRONMENTProgress Report for 1962-63Studies on elemental and energy transfer in lower trophic levels inthe marine environment were initiated in July 1962 after receipt of AECcontract AT(45-1)1751. It should be pointed out that this report coversonly a six-month period, because for bookkeeping purposes the contractwas made retroactive to 1 April 1962, at the request of the contractor.The major equipment described in the original proposal has beenobtained. The gamma scintillation spectrometer has been calibrated forCs137 and Zn65 and is being calibrated for Fe59 and Cr51 shortly. Ananalytical ratemeter has just been obtained for use with the spectro-meter. This device permits instantaneous calibration checks and providesa separate power supply for the gamma scintillometer, freeing the scalerfor simultaneous use in counting.The single-channel spectrometer can be converted to a recordingmultichannel instrument by adding an externally-driven, precision, ten-turn potentiometer for base-level voltage control. Such modificationswould make it possible to check the instrument calibration for a mixtureof isotopes, to discriminate mixtures of isotopes with close energylevels, and, in future experiments, to determine the half-lives and energylevels of unidentified isotopes. This modification will also be valu-able in the routine counting of background, particularly in multiple-isotope work.In compliance with regulations of the University Radiation Committee,an office-laboratory has been converted into an isotope preparation roomand the cement floors of our main laboratory and instrument room werecovered with asphalt tile.A final design of the "aquastat" was decided upon and constructionis under way. A careful study was made to select the best sources ofillumination to simulate conditions in the sea with respect to both in-tensity and spectral composition. A combination of standard and high-output lamps, in several "colors," appears to be the most appropriate.We are exploring the possibility of replacing the lamp ballasts withmagnetic frequency multipliers in order to decrease substantially theweight of the equipment, to provide greater flexibility in intensitycontrol, and to remove a source of waste heat. We are using a 1-horse-power, water-cooled condensing unit for the cooling end of the "aquastat"and a "cal-rod" type heating element. Aluminum egg-crate dividers willdiminish light leakage and thermal convection currents between compartments.At present, five genera of phytoplankton organisms are being main-tained in uni-algal, bacteria-free culture. The organisms are: Skeletonemacostatum, Melosira R., Fragillaria oceanica, Euglena sp., and four2species of Chaetoceros. A number of other species have been in culturefor a short time. We are investigating the possibility of improving growthcharacteristics of cultures by using cellulose gums as inert suspendingmedia.Nutrient enrichment cultures are being brought back from all hydro-graphic cruises so that in the future additional species of phytoplanktonwill be available as food for herbivores. We expect to have cultures ofalga l species representing a wide range of cell dimensions and environ-mental preferences.Artemia salina is being used as the initial grazer, but we areattempting to maintain some of the larger pelagic copepods in the labor-atory. Work at other marine laboratories indicates that it is feasibleto maintain copepodite stages and adults in the dark at low temperatures,without feeding, for several weeks. We have been successful in thisregard with Calanus finmarchicus, a fairly abundant species off the coastof Oregon in winter. We are investigating the possibility of working withCalanus cristatus, which is abundant in Oregon waters in the spring andsummer. This species is quite large and apparently is important as asecond trophic level grazer and concentrator of radionuclides.Artemia .was originally selected as the experimental grazer becauseof its availability and large size. However, it was recognized that thefeeding behavior of Artemia might differ in some respects from that ofnatural marine zooplankton. If experiments indicate that feeding ormetabolic behavior are different in the two taxa, then copepods may beused to "calibrate" Artemia. However, we will still attempt to find atrue marine herbivorous zooplankter that can be either cultured or main-tained throughout the year. A literature search relating to the culturingof marine copepods is under way.After preliminary work with Artemia, it was found necessary to revisethe experimental technique for studies testing direct uptake of radio-nuclides from solution, because a "salt effect" was encountered. Theerratic counts obtained in early experiments comparing radionuclide countsper unit weight of Artemia (cpm/mg) suggested that something in additionto the animals was affecting the results. The erratic counts occurredwhen the organisms were removed from the radioactive solution and counteddry;Subsequent experiments comparing cpm/mg in rinsed and non-rinsedsamples showed that over a range of sample weights, counts per unit weightwere more uniform and always higher in the rinsed samples than in the non-rinsed samples. Dry weights of non-rinsed samples apparently includedthe weight of varying amounts of salt crystals adhering to the animals andto the filter used to separate the Artemia samples from solution. Expressionof results as cpm/mg was actually an expression of cpm/mg of radioactiveArtemia plus non-radioactive salt crystals. Rinsing, on the other hand,3removed the salt from the animals and the filter and gave a true expressionof cpm/mg of Artemia. Covariance analysis on series of rinsed and non-rinsed samples showed a true difference between the two treatments.In addition to the laboratory work started, we have undertaken thespecies analysis of zooplankton collections made off the Oregon coast.A knowledge of species composition and distribution will allow meaningfulextrapolation of laboratory data to natural situations. These data willalso be used later for analysis of population diversity and speciesassociations. This information is of considerable theoretical interestwith regard to energy-flow ecosystems.The succinoxidase enzyme activity of muscle tissue and whole orga-nisms of bathypelagic fish and large zooplankton is being analyzed inconjunction with work on oceanic nekton under the direction of Dr. WilliamPearcy AT(45-1)1726. The measurement of such activity provides a methodof determining respiratory metabolism which can be used instead of theoxygen uptake experiments. This technique will be used in measuring therespiration of organisms employed in our "aquastat" experiments.Major modifications in the original method have been made to correctfor absorption by carotenoids and to produce data which will be reliableon the basis of weight. Work has also begun on an examination of alter-native pathways to the succinoxidase system, since low activity may be aresult of shunts rather than inherent low respiration. Instrumentationis being designed to measure gaseous (02) respiration before the enzymaticmethod is applied to a specimen.

Energy conversion and element transfer in lower trophic levels in the marine environment

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Energy conversion and element transfer in lower trophic levels in the marine environment

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