494
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240
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01
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5 80
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40
D. J. TRANTER:
,
,
,
,
"
"
,
,
,
TROPICAL lO"N,E"","
Y-I ·90X • 67.7
,
,
,
,
,
,
,
"
"
" ,
,
,
"
SUBTROPICAL ZONE
Y. 0·6SX. 91·3
,' . *
**
Y-I·S7X + 73 ·9
* CORRELATION SIGNIFICANT AT 95\ LEVEL
* * CORRELATION SIGNIFICANT AT 99',. LEVEL
O+-----~----~-----,------T_--~
o
w
~
~
~
I~
LIGHT-SATURATED PROOUCTIVITY (mgC m- 2 h-' l
Fig. 11. Regressions of simulated in situ production on light-saturated productivity.
(Data from JITIS, 1969)
are given for tropical and subtropical zones. No attempt is made in this review to place
these levels in a geographic context. The emphasis is on seasonal variation and the interaction of one trophic level with another.
In Table 2, the levels of these biological properties are compared in terms of their
carbon equivalents. The mean seasonal carbon equivalent at each trophic level is expressed
Table 1. Mean levels for various biological properties along meridian 110° E. During six cruises in
1962 - 63. (I, day value/night value)
Biological Property
Cruise
Jan- Feb Mar-Apr May- Jun Jul-Aug Aug-Sep Oct-Nov
1963
1963
1963
1963
1962
1962
(a) Tropical Zone
(North of 18° S.)
Zooplankton Biomass
31/ 87
47171
42/63
63/ 109
84/ 113
50/ 46
(mgm- 3 )
Total MWT Catch (g dry
9.66
15.98
16.28
12.90
21.10
23.38
weight per 10 000 m column)
MWT Zooplankton
2.00
4.80
2.30
2.12
7.85
5.62
MWT Macroplankton
2.80
3.65
5.78
5.90
6.10
9.37
MWT Micronekton
4.56
7.25
7.93
4.43
6.52
7.97