DISTRIBUTIONAND ABUNDANCE OFBENTHICASSEMBLAGES IN EL-GAMIL BASIN (LAKE MANZALAH, EGYPT)

DISTRIBUTIONAND ABUNDANCE OFBENTHICASSEMBLAGES

IN EL-GAMIL BASIN (LAKE MANZALAH, EGYPT)
B) MACROBENTHOS
BY
MOHAMED R. A. FISHAR*
*NationalInsfitute o.fOceanography & Fisheries, Inland Water &Aquaculture Branch
Key words: Macrobenthos, Lake Manzalah, distribution, composition, pollution.
ABSTRACT
Macrobenthic samples were collected during summer and winter
of 1997 from EI-Gamil Basin (part ofLake Manzalah). Samples were
taken from 20 stations arranged in three sections.
Macrobenthic community consistedfrom fifteen species belonging
to four phyla, Arthropoda (six species), Annelida (four species),
Mollusca (four species) and Coelenterata (one species). Most ofthese
species are ofmarine origin. The abundance ofmacrobenthic species
was closely correlated with nature ofbottom sediments, turbidity and
salinity. The low number ofbenthic invertebrates at stations ofsection
1 is due to action of water current comingfrom connecting canal.
Results showed that the wastewater treatment plant having no effect
on the total number ofmacrobenthic.individuals but it decreased the
number’ ofspecies (diversity) which still tolerate organic pollution. In
addition, large number of dead and empty shells of Mollusca are
observed in the area opposite to the plant effluent.