for other Crustacea ; Lasker (1966), however, found a higher value for
euphausids, 7.2%. If we assume that displacement volume is a fair
estimate of wet weight, then a factor can be used to convert displacement volume as d / m 2 t o gC/m2. The correct conversion factor depends upon the relative distribution of copepods and other forms in the
zooplankton ; sometimes copepods will predominate and sometimes
euphausids, in which case the factor will shift from 5.6 to 7.2%. An
approximation of 6.5% will be used.
The estimate of carbon in the secondary production is given, for
example, in the fist line of Table IV:
1-82 gC/m2 x (169 km2. lo3 x lo6 m2) x 3-46 gen
tons C/year
= 0.106.106 tons C/year.
The results are given in column M, ; in column M,, the quantities are
raised by 1.33, t o take into account the possible halt to zooplankton
production caused by intermittent upwelling. Columns N1 and N , give
the transfer coefficients, which are the ratios of secondary production
to primary production, calculated as M,/D or M,/D. These coefficients
are analogous to Slobodkin's ecological efficiency (1959), which is the
ratio of yield from one trophic level t o that from a second trophic level.
I n column M , is tabulated the secondary production in tons
C. 106/year, where the annual production is considered as occurring
only in the upwelling season ; of course, some production occurs in such
areas outside the season of upwelling, and in one case, at least, off the
Orissa coast of India, there is some production during both the northeast and the south-west monsoons, but that during the north-east
monsoon cannot be generated by coastal upwelling in the ordinary
sense. The greatest production (>5.0. lo6 tons C/year) is found in the
three major upwellings Peru, Canary and Benguela and this arbitrary
level is not found outside them. It appears that the Canaq Current is
not so rich in zooplankton as the other two (c. 10. lo6 tons, as opposed
to 17.106 tons in the Peru Current and about 20.106 tons in the
Benguela Current). The quantity of carbon in the California Current
(5. lo6 tons) is considerably less. It is possible that the major upwellings in the southern hemisphere are richer than thos6 in the
northern hemisphere, as was suggested from the radiocarbon measurements. In terms of secondary production, the upwellings in the Indian
Ocean or in the Indonesian area are less productive (1. lo6 or 2. lo6
tons Clyear), mainly because the areas are smaller and more limited in
season. The production in the Costa Rica Dome appears t o be very
high, but this is because production continues for most Qf the year.
In columns N , and N , are given the transfer coefficients, the ratios
euphausids, 7.2%. If we assume that displacement volume is a fair
estimate of wet weight, then a factor can be used to convert displacement volume as d / m 2 t o gC/m2. The correct conversion factor depends upon the relative distribution of copepods and other forms in the
zooplankton ; sometimes copepods will predominate and sometimes
euphausids, in which case the factor will shift from 5.6 to 7.2%. An
approximation of 6.5% will be used.
The estimate of carbon in the secondary production is given, for
example, in the fist line of Table IV:
1-82 gC/m2 x (169 km2. lo3 x lo6 m2) x 3-46 gen
tons C/year
= 0.106.106 tons C/year.
The results are given in column M, ; in column M,, the quantities are
raised by 1.33, t o take into account the possible halt to zooplankton
production caused by intermittent upwelling. Columns N1 and N , give
the transfer coefficients, which are the ratios of secondary production
to primary production, calculated as M,/D or M,/D. These coefficients
are analogous to Slobodkin's ecological efficiency (1959), which is the
ratio of yield from one trophic level t o that from a second trophic level.
I n column M , is tabulated the secondary production in tons
C. 106/year, where the annual production is considered as occurring
only in the upwelling season ; of course, some production occurs in such
areas outside the season of upwelling, and in one case, at least, off the
Orissa coast of India, there is some production during both the northeast and the south-west monsoons, but that during the north-east
monsoon cannot be generated by coastal upwelling in the ordinary
sense. The greatest production (>5.0. lo6 tons C/year) is found in the
three major upwellings Peru, Canary and Benguela and this arbitrary
level is not found outside them. It appears that the Canaq Current is
not so rich in zooplankton as the other two (c. 10. lo6 tons, as opposed
to 17.106 tons in the Peru Current and about 20.106 tons in the
Benguela Current). The quantity of carbon in the California Current
(5. lo6 tons) is considerably less. It is possible that the major upwellings in the southern hemisphere are richer than thos6 in the
northern hemisphere, as was suggested from the radiocarbon measurements. In terms of secondary production, the upwellings in the Indian
Ocean or in the Indonesian area are less productive (1. lo6 or 2. lo6
tons Clyear), mainly because the areas are smaller and more limited in
season. The production in the Costa Rica Dome appears t o be very
high, but this is because production continues for most Qf the year.
In columns N , and N , are given the transfer coefficients, the ratios