SOME FACTORS AFFECTING THE PRIMARY PRODUCTION OF PHYTOPLANKTON IN LAKE BURULLUS

SOME FACTORS AFFECTING THE PRIMARY PRODUCTION
OF PHYTOPLANKTON IN LAKE BURULLUS
ABDEL – AZIZ M.RADWAN
National Institute of Oceanography and Fisheries, Baltim Research Station
Keywords: Lake Burullus – Primary production – Phytoplankton – Physico-chemical
conditions.
ABSTRACT
This study which was carried out at the different stations and sectors of Lake Burullus
during the period from January till December 2000 showed that the identified species of
phytoplankton community in Lake Burullus during the period of study included the classes
of Bacillariophyceae, Cyanophyceae, Chlorophyceae, Euglenophyceae and Dinophyceae.
The total number of species recorded during this period was 65 species. The standing crop
and primary production of phytoplankton showed pronounced variations at different
stations and months correlated with physicochemical conditions of water especially
phosphate , nitrate and silicate contents. Stations 6,10 and 15 were the most productive in
the eastern sector ,the middle sector, and the western sector respectively. The productivity
was lower at stations nearby the drains mouth. Positive correlation was observed between
the transparency and the net production. Levels of temperature and dissolved oxygen are
among the factors affecting the productivity.
In general, the dominance of Bacillariophyceae in the lake plays an important role in
productivity, where it represented more than 65 % to the total count of phytoplankton
during the period of study.
The results obtained indicated that, Lake Burullus harboured lower phytoplankton
standing crop and primary production as compared with that previously recorded .