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The standardization and comparison of measurements of primary production by the carbon-14 technique
948
Oceanographic Abstracts
JITrs, H. R., 1963. The standardization and comparison of measurements of primary production by the carbon-14 technique. Proc. Con/i, Prim. Prod. Measure., Mar. and Freshwat., Univ. Hawaii, 21 Aug.-6 Sept., 1961, U. S. Atom. Ener. Comm., Div. Tech. lnJbrm., TID-7633: 114-120. A prerequisite of measurements of primary production by the c--rbon-14 technique and their comparison is the reliable standardization of the amount of carbon-14 added to the sample. This Added Activity must be det,=rmined under conditions identical with the Geiger counting of the phytoplankton samples, e.g. with the same counting geometry and at zero-thickness. In most of the carbon-14 techniques described, self-absorption curves are prepared from the Geiger activities of BaCOs planchets of varying thicknesses containing aliquots of the Added Activity. These curves are then extrapolated to zero-thickness either empirically or mathematically. The empirical extrapolation suffers from two important disabilities; the subjective nature of the curve and the difficulty of preparing thin planchets of BaCOn. The mathematical extrapolation is easier and not subjective but gives large errors as the curve follows neither an exponential nor a hyperbolic function. Attempts to prepare thin planchets show that the curve becomes complex ~ it approaches zero-thickness, due to the increasing importance of back-scattering of the /3particles. Whilst both empirical and mathematical extrapolations can lead to large errors in the estimates of Added Activity at zero-thickness they can be made highly reproducible. This can be checked by the use of estimates of the zero-thickness activity of standard carbon-14 solutions. This allows the reliable comparison of results obtained with the same counting equipmert but not of those from different instruments. A new method has recently been described which consists of determining the absolute activity of the carbon-14 added and the efficiency of the Geiger counter at zero-thickness and hence the Added Activity. This is done by Geiger-counting extremely thin films of plastic labelled with carbon14 and then determining the absolute activities of both the films and the Added Activity by liquid scintillation counting. This method is direct, objective, and simple but requires special equipment. It shows that extrapolations of self-absorption curves can lead to errors of about 20 per cent. Most of the measurements of primary production in the Pacific Ocean have been made by various adoptions of the techniques of Steemann-Nielsen, Sorokin, Doty, and Jitts. The first two measures net, daily prodJction under conditions of natural daylight variation, while the second two measure relative productivity under conditions of constant, artificial illumination. In the technique of Sorokin relative i~roductivity is measured as a preliminary step to obtaining net production. Any attempt to compare the results of the first two techniques to those of the second two, would require the establishment of suitable factors relating them. A direct comparison of the results of two different techniques has been made only for those of Dory and Jitts. This was done by adjacent sampling by the two techniques but using the same Added Activities and Geiger equipment for both techniques. The correlation between the results was significant at better than the 5 per cent level. JONES, E. B. G., 1963. Marine Fungi. 1I. Ascomycetes and Deuteromycetes from submerged wood and drift Spartina. Trans. Brit. Mycol. Sot., 46 (I): 135-144. Sporidesmium salinum spec. nov., a marine hyphomycete on wood submerged in the sea is described. The following are recorded, with discussions where necessary: Dictyosporium pelagica (Linder) G. C. Hughes apud Jones; D. toruloides (Corda) Gu6gen; Piricauda pelagica Johnson, transferred to Monodictys; M. putredinis (Wallr.) Hughes; Culcitalna achraspora Meyers and Moore; and Humicola alopallonella Meyers and Moore. The Ascomycetous species Ceriosporopsis halima Linder, Halosphaeria circumvestita Kohlmeyer, If. torquata Kohimeyer, Lulworthia fucicola Sutherland, L. medusa (Ell. and Ev.) Cribb and Cribb, L. opaca (Linder) Cribb and Cribb and Sphaerulina orae-maris Linder are recorded and discussed. JONES, P. G. W., 1963. The effect of chloroform on the soluble inorganic phosphate content of unfiltered sea water. J. Cons. Int. Exp. Mer., 28 (1): 3-7. The addition of chloroform to unfiltered sea water from the Menai Straits caused an increase in the inorganic phosphate content of the sample. The phenomenon may be the result of liberation of phosphate from particulate organic matter. JONES, P. G. W. and S. M. HAQ, 1963. The distribution of Phaeocystis in the Irish Sea. ,/. Cons. Int. Exp. Met., 28 (1): 8-20. The distribution of Phaeocystis in Liverpool Bay and Caernarvon Bay was investigated from 1957 to 1959. Each year a spring outburst was recorded from Liverpool Bay, but this flagellate was sparse or absent in Caernarvon Bay. The time of the bloom differed each year but showed some relation to the water temperature. The period of the Phaeocystis bloom usually coincided with the spring minimum of dissolved phosphate m these waters. Circumstantial evidence suggests that some factor associated with terrestrial drainage is necessary to trigger a Phaeocystis bloom. KgnUgA, K., 1963. 27. Effects of a breakwater on the oscillations of bay water. (In Japanese, English summary). Bull. Earthquake Res. Inst., Tokyo, 41 (2): 403-418. The effects i r a large breakwater with a constricted opening on the oscillations in a bay are examined with a ~imple, one-dimensional mathematical n-.odel. The bay is separated into t ~ o parts by a
Oceanographic Abstracts
JITrs, H. R., 1963. The standardization and comparison of measurements of primary production by the carbon-14 technique. Proc. Con/i, Prim. Prod. Measure., Mar. and Freshwat., Univ. Hawaii, 21 Aug.-6 Sept., 1961, U. S. Atom. Ener. Comm., Div. Tech. lnJbrm., TID-7633: 114-120. A prerequisite of measurements of primary production by the c--rbon-14 technique and their comparison is the reliable standardization of the amount of carbon-14 added to the sample. This Added Activity must be det,=rmined under conditions identical with the Geiger counting of the phytoplankton samples, e.g. with the same counting geometry and at zero-thickness. In most of the carbon-14 techniques described, self-absorption curves are prepared from the Geiger activities of BaCOs planchets of varying thicknesses containing aliquots of the Added Activity. These curves are then extrapolated to zero-thickness either empirically or mathematically. The empirical extrapolation suffers from two important disabilities; the subjective nature of the curve and the difficulty of preparing thin planchets of BaCOn. The mathematical extrapolation is easier and not subjective but gives large errors as the curve follows neither an exponential nor a hyperbolic function. Attempts to prepare thin planchets show that the curve becomes complex ~ it approaches zero-thickness, due to the increasing importance of back-scattering of the /3particles. Whilst both empirical and mathematical extrapolations can lead to large errors in the estimates of Added Activity at zero-thickness they can be made highly reproducible. This can be checked by the use of estimates of the zero-thickness activity of standard carbon-14 solutions. This allows the reliable comparison of results obtained with the same counting equipmert but not of those from different instruments. A new method has recently been described which consists of determining the absolute activity of the carbon-14 added and the efficiency of the Geiger counter at zero-thickness and hence the Added Activity. This is done by Geiger-counting extremely thin films of plastic labelled with carbon14 and then determining the absolute activities of both the films and the Added Activity by liquid scintillation counting. This method is direct, objective, and simple but requires special equipment. It shows that extrapolations of self-absorption curves can lead to errors of about 20 per cent. Most of the measurements of primary production in the Pacific Ocean have been made by various adoptions of the techniques of Steemann-Nielsen, Sorokin, Doty, and Jitts. The first two measures net, daily prodJction under conditions of natural daylight variation, while the second two measure relative productivity under conditions of constant, artificial illumination. In the technique of Sorokin relative i~roductivity is measured as a preliminary step to obtaining net production. Any attempt to compare the results of the first two techniques to those of the second two, would require the establishment of suitable factors relating them. A direct comparison of the results of two different techniques has been made only for those of Dory and Jitts. This was done by adjacent sampling by the two techniques but using the same Added Activities and Geiger equipment for both techniques. The correlation between the results was significant at better than the 5 per cent level. JONES, E. B. G., 1963. Marine Fungi. 1I. Ascomycetes and Deuteromycetes from submerged wood and drift Spartina. Trans. Brit. Mycol. Sot., 46 (I): 135-144. Sporidesmium salinum spec. nov., a marine hyphomycete on wood submerged in the sea is described. The following are recorded, with discussions where necessary: Dictyosporium pelagica (Linder) G. C. Hughes apud Jones; D. toruloides (Corda) Gu6gen; Piricauda pelagica Johnson, transferred to Monodictys; M. putredinis (Wallr.) Hughes; Culcitalna achraspora Meyers and Moore; and Humicola alopallonella Meyers and Moore. The Ascomycetous species Ceriosporopsis halima Linder, Halosphaeria circumvestita Kohlmeyer, If. torquata Kohimeyer, Lulworthia fucicola Sutherland, L. medusa (Ell. and Ev.) Cribb and Cribb, L. opaca (Linder) Cribb and Cribb and Sphaerulina orae-maris Linder are recorded and discussed. JONES, P. G. W., 1963. The effect of chloroform on the soluble inorganic phosphate content of unfiltered sea water. J. Cons. Int. Exp. Mer., 28 (1): 3-7. The addition of chloroform to unfiltered sea water from the Menai Straits caused an increase in the inorganic phosphate content of the sample. The phenomenon may be the result of liberation of phosphate from particulate organic matter. JONES, P. G. W. and S. M. HAQ, 1963. The distribution of Phaeocystis in the Irish Sea. ,/. Cons. Int. Exp. Met., 28 (1): 8-20. The distribution of Phaeocystis in Liverpool Bay and Caernarvon Bay was investigated from 1957 to 1959. Each year a spring outburst was recorded from Liverpool Bay, but this flagellate was sparse or absent in Caernarvon Bay. The time of the bloom differed each year but showed some relation to the water temperature. The period of the Phaeocystis bloom usually coincided with the spring minimum of dissolved phosphate m these waters. Circumstantial evidence suggests that some factor associated with terrestrial drainage is necessary to trigger a Phaeocystis bloom. KgnUgA, K., 1963. 27. Effects of a breakwater on the oscillations of bay water. (In Japanese, English summary). Bull. Earthquake Res. Inst., Tokyo, 41 (2): 403-418. The effects i r a large breakwater with a constricted opening on the oscillations in a bay are examined with a ~imple, one-dimensional mathematical n-.odel. The bay is separated into t ~ o parts by a