352
ALAIN HOliRNIA
Schan ( I Wfi) 011 IZ?/drodic*/yo?r ; in the cilt;ie of C'hlorelln, another, shorter
mtrxirnum is observed in t h csrly light, phase after the release of
sutospores (Hitad c.f al., IB(i3 ; I'irson i~11tl T,orcnzen, 1966). On thc other
hand, the miwine phyt oplruiktjer fi'.t/wiiodi)iium nelso?t,ii Mtwtin grown
in light/dikrk cyclrs (tTocha~hki~ r w l Teal, 19G4) had a minimum
respiratory rutc in the (lark and w w more sensitive to malonate at the
beginning of the dark period and in the middle of the light period.
Chttnges in rcspircktory quotient are also known and presumably
reltited to nitrtrtc. utilizution (Ried ~t aZ., 1963).
l'erxistent rhythms in respiratory metabolism ure also encountered
in highar nquc-ttic plants (Miysta and Yamamoh, 1969).
The few mcasurenients made at sea or in lakes by tshe light-and-darkbottle oxygen method may be summarized as follows: no significant
variations (Ohle, 1958) ; increasing rate from sunrise to noon--nocturnal
rate, estimutrd from i9i situ changes in opeti water, being at a middle
love1 (Ryther ut d., 1958) ; a mid-afternoon though inconstant maximum
(Lorenzen, 1963).
On the other hand, recent field data on electron transport system
(ETS) activity provided evidence of a diel cycle of low amplitude, in
phase with a nitrate reductase cycle (Packard et ol., in press) but, in
view of other experiments, Packard's feeling (personal communication)
is that " most likely, phytoplankton E'I'S activity is not marked by
diel periodkitty ".
x I . EXC!lEE'FION
Excretion certainly deserves a separate section in this review.
Unfortunately, nothing is reported about. its diel variations, as far as
the iciitjlior i s tiware.
As t i n introcluction, 1atboriltor.y work by Eppley and Moan ( I m g ,
Hellcbrirrt (1 9(35), Eppley el 02. (1 9ti7) atid Huntsman (1 972) may he
consulted, and references t80 field studics found in Thomas (1971) and
others.
Will roitdet*s plriise nota that Itere is a gap to be filled.
XII. h'UTItlENT UPTAKE
A , Nitrogen
Let, us first consider the few availuble diLta on thc, d i d viiri:itionn
of nitrate, nit8rita and ammoniunt content of HI:;L water.
tntegrated values of N-NO, in the upiw 1.50 nr of thc SILt' @HWJ WiL
offered some evidence for a noctuniol ii~r:reu~c. up to a morning maximum (Rythcr et d., 1961) ; however, variutions in nurfwe wutw of
ALAIN HOliRNIA
Schan ( I Wfi) 011 IZ?/drodic*/yo?r ; in the cilt;ie of C'hlorelln, another, shorter
mtrxirnum is observed in t h csrly light, phase after the release of
sutospores (Hitad c.f al., IB(i3 ; I'irson i~11tl T,orcnzen, 1966). On thc other
hand, the miwine phyt oplruiktjer fi'.t/wiiodi)iium nelso?t,ii Mtwtin grown
in light/dikrk cyclrs (tTocha~hki~ r w l Teal, 19G4) had a minimum
respiratory rutc in the (lark and w w more sensitive to malonate at the
beginning of the dark period and in the middle of the light period.
Chttnges in rcspircktory quotient are also known and presumably
reltited to nitrtrtc. utilizution (Ried ~t aZ., 1963).
l'erxistent rhythms in respiratory metabolism ure also encountered
in highar nquc-ttic plants (Miysta and Yamamoh, 1969).
The few mcasurenients made at sea or in lakes by tshe light-and-darkbottle oxygen method may be summarized as follows: no significant
variations (Ohle, 1958) ; increasing rate from sunrise to noon--nocturnal
rate, estimutrd from i9i situ changes in opeti water, being at a middle
love1 (Ryther ut d., 1958) ; a mid-afternoon though inconstant maximum
(Lorenzen, 1963).
On the other hand, recent field data on electron transport system
(ETS) activity provided evidence of a diel cycle of low amplitude, in
phase with a nitrate reductase cycle (Packard et ol., in press) but, in
view of other experiments, Packard's feeling (personal communication)
is that " most likely, phytoplankton E'I'S activity is not marked by
diel periodkitty ".
x I . EXC!lEE'FION
Excretion certainly deserves a separate section in this review.
Unfortunately, nothing is reported about. its diel variations, as far as
the iciitjlior i s tiware.
As t i n introcluction, 1atboriltor.y work by Eppley and Moan ( I m g ,
Hellcbrirrt (1 9(35), Eppley el 02. (1 9ti7) atid Huntsman (1 972) may he
consulted, and references t80 field studics found in Thomas (1971) and
others.
Will roitdet*s plriise nota that Itere is a gap to be filled.
XII. h'UTItlENT UPTAKE
A , Nitrogen
Let, us first consider the few availuble diLta on thc, d i d viiri:itionn
of nitrate, nit8rita and ammoniunt content of HI:;L water.
tntegrated values of N-NO, in the upiw 1.50 nr of thc SILt' @HWJ WiL
offered some evidence for a noctuniol ii~r:reu~c. up to a morning maximum (Rythcr et d., 1961) ; however, variutions in nurfwe wutw of