FLOATING AQUATIC WEEDS AND CONTROL MEASURES OR METHODS

Looking at fish farming toda, we can say that Aquatic weeds are unwanted plants that grow within the water body and along the margins. These plants remove a large amount of nutrients from the water, which otherwise would go into the production of plankton growth. Even the poor fish crop that is produced in weed chocked water is difficult to harvest. The fish are subjected to stress due to dissolved oxygen depletion and wide fluctuation between the dissolved oxygen values of the day and night.

Explanation: Dense growth of submerged weeds restricts fish movement and interferes with fishing operations.

Filamentous algae often get entangled in the gills of the fish and suffocate them.

Floating weeds such as water hyacinth, pistian etc. Very often cover the entire water surface cutting off light drastically, thus resulting in critical reduction in primary productivity of the pond.

The common aquatic weeds causing problems in fish culture ponds are broadly classified according to their nature of occurrance into major groups such are FLOATING, EMERGENT,SUBMERGED AND MARGINAL.

1 Preventive method or control.

2 Manual methods.

3 Chemical methods.

4 Biological methods.