A biological study of Durvillaea antarctica (Chamisso) Hariot and D ...

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Table 7.1
Range of stipe lengths in successive size classes.
Size class
(kg)
Stipe length (em)
10 11 12 13 14 15 16 17 18 19 20 21 22+
o - 0.5
0.5 - 2
2 "- 4
4 - 6
6 - 8
8 - 10
10 - 15
15 - 20
7.2 GROWTH
(a)
Localisation of growth in the lamina:
No clear intercalary meristem or apical meristem was detectoble
microscopically in either species, although the hole punching
experiment l sho'Vled that grO\.;rth was localised to a slight extent in
D, antarctica laminae.
Results of the hole punching e~eriment;
Unfortunately many of the tagged specimens at Oaro were swept
away during autumnal storms of 1974. Only 10 of the original 25 plants
survived longer than 12 months. Mortality was even hj.gher at Ir.on
Gate Stream, mainly because vandals cut several plants.
The raw edges of most holes healed over \.;rithi : a few weeks,
although in some cases, isopods enlarged the holes and prevented
healing. These damaged holes were excluded from any measurements of
hole size. Some specimens at Oaro tore part way along the line of
holes, but in most cases, this was confined to the distal tllird of
the lamina.
See Chap'cer 2 fo:!::
a description of the mel..:hods.