PLANKTON IN NITROOEN AND PHOSPHORUS CYCLES
161
PHOSPHORUS EXCRETED BY ZOOPLANKTON
Nitrogen excreted
Phosphorus excreted
daily
daily
Body wt yo Body N Body wt yo Body P
A
A
Reference
Food
/
\
/
\
llslmg
Mlglmfl
usw
usw
usw
usw
usw
usw
FSW
usw
usw
Algal diets
Starved
Starved
Starved
Algal diets
FSW
FSW
FSW
FSW
FSW
FSW
FSW
FSW
FSW
FSW
43.1
3.6
34
-
-
-
24
12.7
0.7 1
0.30
0.70
0.58
-
-
9.3-12.2
9-8
24.6
38.1
7.1 1-10.5
13.4
2-74
2.98
1.73
2-47
1.44
48
-
-
-
-
-
-
14.2
1.1
0.6
1-1
0.9
3*1*
2*7*
8-1 1
8.1
20
38
6.6-9.6
14.6
3.7
2.6
1 -6
2.1
1.2
11
2.4
6-6
1.37
1.27
1.02
1.52
0.93
1.27
3.7
9.4
-
2.39
-
-
-
-
-
2.21
0.66
-
-
-
-
Harris (1969)
Martin (1968)
Hargrave and Geen (1968)
Hargrave and aeen (1968)
Pomeroy et al. (1963)
Raymont et al. (1968)
Beers (1964)
Conover and Corner (1968)
Cowey and Corner (19638)
Comer el al. (1966)
Corner el al. (1967)
Butler el d . (1970)
Butler el al. (1969)
Jawed (1969)
~~~~~
FSW = filtered sea water.
metabolic activity and is not sensibly affected by the release of semidigested faecal material.
Average values for rates of nitrogen excretion by zooplankton are
included in Table VIII. The differences are considerable. However,
a8 nitrogen excretion has been shown to vary with food level, tempera-