Biology Reference
In-Depth Information
of this strain was much lower to other species of this genus, i.e.
Aph
.
fl os
-
aquae
,
Aph
.
gracile
or
C
.
raciborskii
that are known to produce CYN (Shaw
et al
., 1999). The toxic cyanobacterial blooms of
serious nature in Australia are
M
.
aeruginosa
,
No
.
spumigena
,
A
.
circinalis
(known to produce PSPs)
and
C
.
raciborskii
and the management strategies include the ability to monitor the growth of these
HABs in catchments, source waters and the distribution systems (Steffenson
et al
., 1999). Blooms
of
M
.
aeruginosa
(Atkins
et al
., 2001) and
Cylindrospermopsis
(Fitzgerald, 2001) have frequently been
reported from Australia. Members of the order Chroococcales such as two forms of
Aphanothece
and
non-gas vacuolated
Microcystis
species forming benthic communities of embayments in the Myall
Lake of Australia proved to be toxic in mouse bioassay, PP inhibition and ELISA for MCs (Dasey
et
al
., 2005). Orielton Lagoon in Tasmania suffered due to the development of a bloom of
No
.
spumigena
due to lowering of salinity (15-20 g kg
-1
) during December and January with concentrations of
nodularin reaching as high as 2000-3500 µg g
-1
dry weight (Jones
et al
., 2006). Toxic cyanobacterial
blooms of
Microcystis
and
Anabaena
are of wide spread occurrence in the Lakes of Victoria (Fig. 25).
Blooms of
Aphanizomenon
and
Nodularia
occur in the southwest wetlands on the Swan coastal plain
of western Australia. Out of a total of 32 natural bloom samples, 28 proved to be toxic with MC
concentrations ranging from 1645 to 8428.6 µg L
-1
. The distribution of MC variants revealed 100%
by MC-LR followed by MC-YR (71.4%) and MC-RR (60.7%). The presence of nodularins (1664 µg
L
-1
) along with MCs constitutes the fi rst report (Kemp and John, 2006).
Europe
:
Toxic blooms of
M
.
aeruginosa
have been reported from lakes and reservoirs of North and
central Portugal as demonstrated by mouse bioassay with LD
50
of 15 to 75 mg kg
-1
body weight
(Vasconcelos, 1993). Subsequent studies conducted on 30 lakes, rivers and reservoirs revealed toxic
blooms from 18 of these water bodies with a predominance of
M
.
aeruginosa
,
M
.
wesenbergi
,
A
.
fl os
-
Figure 25:
Microcystis aeruginosa
bloom, Lake Mokoan, Victoria, Australia. Picture courtesy Ben Long (University of Surrey),
Mark Schneegurt (Wichita State University) and Cyanosite (www.cyanosite.bio.purdue.edu).
Color image of this figure appears in the color plate section at the end of the topic.
