Efficacité de l'autoépuration et charge organique benthique le long d'un ruisseau pollué par une porcherie

Click to increase image sizeClick to decrease image size

Summary

The mean organic loads in the water and the sediment of a brook polluted by pigsty wastes are compared from the point of contamination down to that of nearly complete recovery.

Between these two points, the per cent kilometric decrease in organic load is similar for both media. The input of 300 times the benthic energetic load magnifies 3 times the biomass in the upper stations. The ratio of the biomass to the total benthic load is greatest after the water has flown for 3.30 h. The respired energy to total benthic load ratio continually increases during the 5.30 h drainage time. The efficiency of the self purification also reaches its maximum in the last station downstream.