STUDIES ON PHYTOPlANKTON IN SOME POLLUTED AREAS OF Ll\.KE MANZALAH

STUDIES ON PHYTOPlANKTON IN SOME
POLLUTED AREAS OF Ll\.KE MANZALAH
EZZAT A. IBRAHIM

National Institute of Oceanography and Fisheries.

ABSTRACT
Standing crop and species c~sition of the phytoplankton
were ‘investigated in some polluted and non-polluted areas of
lake Manzalah. The samples were collected from eight
stations for a period of one year (~ummer, 1986-Sprins,
1987). About 170 taxa were recorded and distributed in the
following taxonomic groups: Bacillariophyceae, 83;
Chlorophyceae, 28; Euglenophyceae, 10; Dinophyceae, 8;
Crytophyceae, 1.
Two distinct peaks were noted, the major one in winter
and the second minor in spring. The species c~sition
during the annual peaks changed from site to site and from
season to season. The most important species responsible tor
the annual peaKs were: Cyclotella .enegh iniana , Nitzchia
closteriUll, Skeletorv:m>l costotUII, Ankistrodcsnus falcatus,
Spirulina platensis, Anabena variabilis. Oscillatoria
l i_tica and_MeriSlllOpedia ~