EARLY
WARNING SYSTEMS ?
In
developed countries, like the Netherlands, efforts have been made in recent years
to restore animal and plant life, from the sudden deterioration of water quality,
along the river Rhine and Meuse. The RIZA has designed and built a computerized
alarm system, AQUALARM to warn institutes and authorities involved if the water
quality changed suddenly. The RIZA has set up such bioalarm systems at the monitoring
stations. :
Bio-alarm
with fish
For golden orfe swim in an aqarium filled with river water.
Normally, fish swim against the current, six times every hour, river water is
pumped through the aquarium at a higher speed for two minutes to check whether
the fishes are still displaying their normal swimming behavior. If the river water
contains a hazardous substance, the fish try to escape or grow weaker and allow
the current to carry them away. In both cases they touch pressure sensitive wires
at the back of the aquarium. If this happens several times, the computer are then
taken automatically for further chemical place and, if so, which substance is
involved. The fishes given fresh water immediately after the alarm has been raised
and a new batch of fish is put to work every week.
