294
D. H. CUSHINO
off Cape Reinga and off the north-east coast of the South Island of NCW
Zealand. There are upwellings off thc coast of Yucatan in Mexico and
the north coast of Cuba (Bogdanov el al., 1968; Khroinov, 1966b).
VI. THE PRODUCTION OF LIVING MATERIAL IN THE
UPWELLING AREAS
There are many estimates available from the upwelling areas of
primary production, using the radiocarbon technique, and of the stock
of zooplankton, using common nets. The number of observations is
enough to establish a mean value for an area throughout the season,
but there are never enough to show the nature of a seasonal trend within
the upwelling area. The total primary production of an area is given by
raising the mean radiocarbon values as gC/m2 per day by area and
duration of the season. An attempt is made to estimate the production
of the zooplankton, knowing the stock and the generation time, and it
is also raised by area and the number of generations in each season.
From the two estimates, of primary production and of secondary
production, the one of tertiary production is derived by taking 1% of
the first and 10% of the second.
A. Primary production
The radiocarbon method of estimating primary production has been
used extensively since its introduction by Nielsen (1952). Since the
question of respiration in radiocarbon measurement was resolved by
Nielsen and Hansen (1959) many of the doubts raised about the method
during the fifties have disappeared. However, Nielsen (1964) and Goldman (1968) have shown that the earlier method of calibration was at
fault and that most of the measurements made so far have to be raised
upwards by a factor of 1.45. With the introduction of scintillation
methods, the radiocarbon method has become an absolute one (Wolfe
and Schelske, 1967) rather than a relative one, and there is no need for
the old method of calibration. The measurements in the Canary Current
upwelling (Lloyd, 1970) were made with scintillation counters and SO
are not raised by 1.45. Koblentz-Mishke (1965) has combined the surface observations (in mgC/m3 per day) with those made at a number of
depths in the photic layer (in gC/m2 per day) and her regression has
been used to convert many surface observations in mgC/m3 per day
to gC/m2 per day. Provided that enough observations are available, an
annual mean production waa estimated for each area, or subarea.
The data were taken from Steemann Nielsen and Jensen (1957-59)
(from the “ Galathea ” Expedition in the Atlantic and Indian Oceans),
Ryther et al. (1966) (from the “Anton Bruun ” voyage during the
D. H. CUSHINO
off Cape Reinga and off the north-east coast of the South Island of NCW
Zealand. There are upwellings off thc coast of Yucatan in Mexico and
the north coast of Cuba (Bogdanov el al., 1968; Khroinov, 1966b).
VI. THE PRODUCTION OF LIVING MATERIAL IN THE
UPWELLING AREAS
There are many estimates available from the upwelling areas of
primary production, using the radiocarbon technique, and of the stock
of zooplankton, using common nets. The number of observations is
enough to establish a mean value for an area throughout the season,
but there are never enough to show the nature of a seasonal trend within
the upwelling area. The total primary production of an area is given by
raising the mean radiocarbon values as gC/m2 per day by area and
duration of the season. An attempt is made to estimate the production
of the zooplankton, knowing the stock and the generation time, and it
is also raised by area and the number of generations in each season.
From the two estimates, of primary production and of secondary
production, the one of tertiary production is derived by taking 1% of
the first and 10% of the second.
A. Primary production
The radiocarbon method of estimating primary production has been
used extensively since its introduction by Nielsen (1952). Since the
question of respiration in radiocarbon measurement was resolved by
Nielsen and Hansen (1959) many of the doubts raised about the method
during the fifties have disappeared. However, Nielsen (1964) and Goldman (1968) have shown that the earlier method of calibration was at
fault and that most of the measurements made so far have to be raised
upwards by a factor of 1.45. With the introduction of scintillation
methods, the radiocarbon method has become an absolute one (Wolfe
and Schelske, 1967) rather than a relative one, and there is no need for
the old method of calibration. The measurements in the Canary Current
upwelling (Lloyd, 1970) were made with scintillation counters and SO
are not raised by 1.45. Koblentz-Mishke (1965) has combined the surface observations (in mgC/m3 per day) with those made at a number of
depths in the photic layer (in gC/m2 per day) and her regression has
been used to convert many surface observations in mgC/m3 per day
to gC/m2 per day. Provided that enough observations are available, an
annual mean production waa estimated for each area, or subarea.
The data were taken from Steemann Nielsen and Jensen (1957-59)
(from the “ Galathea ” Expedition in the Atlantic and Indian Oceans),
Ryther et al. (1966) (from the “Anton Bruun ” voyage during the