Purifying role of Eichornia crassipes in Nokoue lake, Republic of Benin

Abstract

to determine the values of these monitoring indicators for a better purification yield in a natural environment. The immediate consequence of eutrophication on Nokoue Lake is the proliferation of water hyacinth (Eichhornia crassipes) when salinity conditions are favorable (salinity <7 ‰). The low levels of dissolved oxygen would be due not only to the effects of Eichhornia crassipes(EC) during low-water periods, but also to the organic loads of the lake discharge. Bio Concentration Factor (BCF) is 1/3 for living hyacinth, sedimentary lead is then three (3) times higher than that accumulated in water hyacinth. The threat posed by the proliferation of Eichhornia crassipes could be transformed into an opportunity to de-pollute the environment during the period of high salinity and high level water.