Rm. Crawford et al., SPATIAL AND TEMPORAL DISTRIBUTION OF ASSEMBLAGES OF THE DIATOM CORETHRON CRIOPHILUM IN THE POLAR FRONTAL REGION OF THE SOUTH-ATLANTIC, Deep-sea research. Part 2. Topical studies in oceanography, 44(1-2), 1997, pp. 479-496
Morphometric data in the form of frequency distributions of valve widt
hs (transapical measurements) of the diatom Corethron criophilum have
been plotted for stations between 50 and 47 degrees S on transects 5,
11 and 12 of cruise ANT X/6 to the Atlantic sector of the Southern Oce
an. The profiles largely confirm the picture of sharp differences betw
een the waters as revealed by hydrological, pigment and other biologic
al data. The assemblages to the north, which lie in the southern part
of the Polar Frontal Zone water, are more congruent with those in wate
r to the south, that is presumed to have eddied off the PFZ water, tha
n with interlaying, Antarctic Circumpolar Current water. The profiles
also show how assemblages of this species can be recognised over space
and time. Furthermore, they reveal how a sexual event in the life cyc
le can lead to a rapid change in the character of the assemblage due t
o rapid loss of gametangial cell walls from the water column. (C) 1997
Elsevier Science Ltd.