Composition and Biomass of Phytoplankton
155
Shape
Diagram
[1/2 EL+ CN]
Ellipsoid/cone
T
~~~~~
A
1
Irregular
Irregular
001 I-B-I ~c,
Irregular
Irregular
t-B-t
T
'J:::::=::r. A
1
Figure 10.10. (Continued)
Formula
nB2(A+ B/2)
12
n
- [AB2+ C3+
12
2ED2+ FG2]
n
BC(A- B +-B)
4
A3/4
nAB2/9
Representative
species
Rhodomonas min uta
Gymnodinium
helveticum
Mallomonas
Synura
Ceratium hirundinella
Achnanthes
B: Valve view
C: girdle view
Crucigenia tetrapedia
Peridinium
for water of very productive ecosystems, it may be necessary to filter one liter from
oligotrophic waters. Filtration should be done as rapidly as possible, avoiding
exposure to bright light or high temperature. Addition of a small amount of
magnesium carbonate slurry during the filtration has been suggested to assist in
filtration and to prevent acidity development during extraction, but no filtration
advantages have been observed in practice (Lium and Shoaf, 1978). Moreover, alkaline
acetone is recommended for the extraction (see below).
After the filtration is completed, the filter should be removed while moist and
immediately used in the extraction procedure. When extraction cannot be done right