328
ALA IN SOU KNIA
- -dinofla~:cllat,c?s ( Lt~nskayti, I !N3 ; Hastings and Sweeney, 1964 ;
I-lcllcl)ust, 1965 ; Thomas, 1968 ; Biggley P t d., 1969 ; fweeiie.y,
I !M!h) ;
-cocoolithophorid8 (MjrLaliLnd, 1966 ; Hellebust, 1965 ; Lanskeya,
I !)ti5 ; Swift arid Taylor, I966 ; Peasche, 1967) ;
-c!hlorophyc!eans (Heliebust, 196.5 ; Thomas, 1966).
Maxiniutn rntt.s for sonic species in optimal conditions can reach
rip to 4 G divisions per day (Curl &nd McLeod, 1961 ; Lanskaya, 1963,
1965 ; ‘I1hO11liLs, 19Mi). From the nbove references, one may also draw
the tmtative conclusion that diatoms tend to divide faster than
dinoflcigollnt~os.
Throe species of freshwihr diatoms were grown on an enriched
riiedium arid suspended in situ (‘l?ulling, 1955); in the best growth
conditions, the iilgae divided twice a day.
S U J * ~ W
swi water was enriched and studied in shipboard culture
vessnls (tc:pplcy d al., 1972); division rates ranged from 0.6 to 1-5 per
day t~ccoi*ding to species and media, and from 0.0 to 0.4 in blanks. In
t lie artificial bloom which developed in Strickland’s plastic sphere
(Antin et nl., L963), doubling times of 19-40 hours were noted.
The Guarder and Gran (1927) method of enclosing sea water samples
in bottles and suspending them a t sea has been used not only for the
mcasuremcnt of oxygen production, but also for an estimation of
growth rate. Maximum daily increase in diatom numbers during a
spring blooni was iibout IOO% ((:ran, 1927) or somewhat less (Gaarder
iind ( : r i m , 1987); similar results were obtained by Riley (1952); the
iiveragc ratcx froni a nine-month study conducted by Smayda (1957)
arc t31ic following: 53% increase per day for diatoms end 9.5% decrease
for fl;bgellatc.s. KondrutieviL (1 965) improved this method by prefiltering the euniples in order to eliminate zooplankton, and using fine
nicd~ed clot’lr inat’ead of stoppers to dose the bottles; the latter were
suspontled at sea for 24 hours insteltd of the 3 days in the above experilneiits. liesulthg generation times varied from 6 to 24 hours
depending on stiktions and taxonomic groups. Udng the same ( 1 )
incthod, Kondraticva (1968) recorded doubling rates of 5 to 25 hours
for five s1)cciex of tliutoms and five species of dinoflagellates.
A more rriilistic approach is obviously the counting of organisms
in snmplc~s taken successively at sea; this however gives a “ net ”
increase which takes into account natural elimination caused hy
grazing, sinking iind horizontal advection. Following this principle,
Riley (1!)52) observed an in situ daily increase of 220/, during a rrpring
h o r n , while the rate was 89% for the populations enclosecl in bottles.
ALA IN SOU KNIA
- -dinofla~:cllat,c?s ( Lt~nskayti, I !N3 ; Hastings and Sweeney, 1964 ;
I-lcllcl)ust, 1965 ; Thomas, 1968 ; Biggley P t d., 1969 ; fweeiie.y,
I !M!h) ;
-cocoolithophorid8 (MjrLaliLnd, 1966 ; Hellebust, 1965 ; Lanskeya,
I !)ti5 ; Swift arid Taylor, I966 ; Peasche, 1967) ;
-c!hlorophyc!eans (Heliebust, 196.5 ; Thomas, 1966).
Maxiniutn rntt.s for sonic species in optimal conditions can reach
rip to 4 G divisions per day (Curl &nd McLeod, 1961 ; Lanskaya, 1963,
1965 ; ‘I1hO11liLs, 19Mi). From the nbove references, one may also draw
the tmtative conclusion that diatoms tend to divide faster than
dinoflcigollnt~os.
Throe species of freshwihr diatoms were grown on an enriched
riiedium arid suspended in situ (‘l?ulling, 1955); in the best growth
conditions, the iilgae divided twice a day.
S U J * ~ W
swi water was enriched and studied in shipboard culture
vessnls (tc:pplcy d al., 1972); division rates ranged from 0.6 to 1-5 per
day t~ccoi*ding to species and media, and from 0.0 to 0.4 in blanks. In
t lie artificial bloom which developed in Strickland’s plastic sphere
(Antin et nl., L963), doubling times of 19-40 hours were noted.
The Guarder and Gran (1927) method of enclosing sea water samples
in bottles and suspending them a t sea has been used not only for the
mcasuremcnt of oxygen production, but also for an estimation of
growth rate. Maximum daily increase in diatom numbers during a
spring blooni was iibout IOO% ((:ran, 1927) or somewhat less (Gaarder
iind ( : r i m , 1987); similar results were obtained by Riley (1952); the
iiveragc ratcx froni a nine-month study conducted by Smayda (1957)
arc t31ic following: 53% increase per day for diatoms end 9.5% decrease
for fl;bgellatc.s. KondrutieviL (1 965) improved this method by prefiltering the euniples in order to eliminate zooplankton, and using fine
nicd~ed clot’lr inat’ead of stoppers to dose the bottles; the latter were
suspontled at sea for 24 hours insteltd of the 3 days in the above experilneiits. liesulthg generation times varied from 6 to 24 hours
depending on stiktions and taxonomic groups. Udng the same ( 1 )
incthod, Kondraticva (1968) recorded doubling rates of 5 to 25 hours
for five s1)cciex of tliutoms and five species of dinoflagellates.
A more rriilistic approach is obviously the counting of organisms
in snmplc~s taken successively at sea; this however gives a “ net ”
increase which takes into account natural elimination caused hy
grazing, sinking iind horizontal advection. Following this principle,
Riley (1!)52) observed an in situ daily increase of 220/, during a rrpring
h o r n , while the rate was 89% for the populations enclosecl in bottles.