220
Phytoplankton
Figure 9.1 shows a spectrum obtained for Staurastrum paradoxum, a commonly
occuring green alga in the eutrophic waters of western Lake Erie. The elemental
spectrum demonstrates the presence of metals in a cellular structure. Besides manganese and copper, elevated levels of iron and aluminium were detected. Other elements
indicated in the spectrum are inherent structural components found in biota under
normal conditions, [625].
These results indicate that algae, because of its sensitivity and short generation
time, can be used as an indicator of heavy metal pollution, thus providing an early
warning of pollution.
9.3
Non-Metals
9.3.7
Halogens
Ion selective electrodes have been used to determine halogens in marine algae
[629].
9.3.2
Phosphorus
Darich et al. [630] determined the effectiveness of chemical extraction for predicting
the biological availability of phosphorus in suspended solids as determined by 2-day
and 14-day incubations with the algae Selenastrum capricornutum collected from
several sites in an agricultural catchment in Indiana. The extraction procedures
involved the sequential use of sodium hydroxide and hydrochloric acid, ammonium
fluoride, sodium hydroxide and hydrochloric acid, nitrilotriacetic acid, and hydroxyaluminium resin. Some 21-25 % of total sediment phosphorus was biologically
available.
Inorganic phosphorus extracted with sodium hydroxide was significantly correlated with both 2-day and 14-day available phosphorus, although extraction removed
amounts of inorganic phosphorus that exceeded available sediment phosphorus by a
relatively constant amount. A single extraction with 0.1 M sodium hydroxide could be
used to estimate both short- and longer-term algal-available phosphorus in stream
sediments derived from non-calcareous soils where amorphous iron and aluminium
were principally responsible for phosphorus retention.
Phytoplankton
Figure 9.1 shows a spectrum obtained for Staurastrum paradoxum, a commonly
occuring green alga in the eutrophic waters of western Lake Erie. The elemental
spectrum demonstrates the presence of metals in a cellular structure. Besides manganese and copper, elevated levels of iron and aluminium were detected. Other elements
indicated in the spectrum are inherent structural components found in biota under
normal conditions, [625].
These results indicate that algae, because of its sensitivity and short generation
time, can be used as an indicator of heavy metal pollution, thus providing an early
warning of pollution.
9.3
Non-Metals
9.3.7
Halogens
Ion selective electrodes have been used to determine halogens in marine algae
[629].
9.3.2
Phosphorus
Darich et al. [630] determined the effectiveness of chemical extraction for predicting
the biological availability of phosphorus in suspended solids as determined by 2-day
and 14-day incubations with the algae Selenastrum capricornutum collected from
several sites in an agricultural catchment in Indiana. The extraction procedures
involved the sequential use of sodium hydroxide and hydrochloric acid, ammonium
fluoride, sodium hydroxide and hydrochloric acid, nitrilotriacetic acid, and hydroxyaluminium resin. Some 21-25 % of total sediment phosphorus was biologically
available.
Inorganic phosphorus extracted with sodium hydroxide was significantly correlated with both 2-day and 14-day available phosphorus, although extraction removed
amounts of inorganic phosphorus that exceeded available sediment phosphorus by a
relatively constant amount. A single extraction with 0.1 M sodium hydroxide could be
used to estimate both short- and longer-term algal-available phosphorus in stream
sediments derived from non-calcareous soils where amorphous iron and aluminium
were principally responsible for phosphorus retention.