Effects of a thermal pollution        

      Heat and hot water result from many industrial processes. They are in particular by-products of the activity of the power stations and nuclear. The water rejected into the marine mediums has harmful effects, primarily on the marine animal-life.

      The pollution thermal has effects difficult to define with precision. One observes significant interferences of the reduction in the salinity of water and variations of this one in time and space. Several actions of such a pollution were however determined. It was in particular established that the hotter the temperature of rejected water is and more harmful is its effect on the benthic organizations.

        On the algae, the action of a thermal pollution is very variable. One noted opposite effects is strong proliferations or on the contrary a significant mortality. The metabolism of the algae, the phytoplanktons, the benthic macrophagesis very faded by heated water.

        One will thus be satisfied to point out some facts of observation which seem to have characters of general data:

- one observes a numerical imbalance between the existing species in consequence of the differences in tolerances to the heating of  water, from where modification with in the Community of which the structure and balance are faded.

- the distribution of the settlement is established in three zones: a died zone, a zone with reduced specific diversity and finally a zone where one observes a re-establishment in a gradual way of the flora of the biotope considered.

polmar@manon.org - - créé le 12/04/2000