From 21 August until 6 November 1994, the number of A.ovalisporum filaments
varied between 235 and 2575 ml"1
, corresponding to a cumulative length
of 47-443 m H. Wet weight biomass varied from 527 ig I"1
to a maximum of 6000
ug I"1
at the optimal depth (Table III). The maximum number of heterocysts
observed was 6.6 per 1000 um of filament in a sample from 12 September.
Throughout October, the heterocyst number remained relatively constant,
decreasing to 1.5 per 1000 um filaments in early November. The number of
akinetes varied between 0.3 per 1000 (am at the end of August and 4.0 per 1000 um
at end of October (Table III).