A STATISTICAL MODELLING OF PHYTOPLANKTON EUTROPHICATION IN THE EASTERN HARBOUR, A

A STATISTICAL MODELLING OF PHYTOPLANKTON

EUTROPHICATION IN THE EASTERN HARBOUR,

ALEXANDRL4,EGYP~
By
R. R. ABDALLA*; F. A. ZAGHLOUL

AND N. R. HUSSEIN

*National Institute of Oceanograpgy and Fisheries,Alexandria, Egypt.
Key words: Eutrophication, Phytoplankton, Nutrients, Modelling.
ABSTRACT
The Eastern Harbour of Alexandria is a shallow semiclosed basin
receives a constant high input of sewage effluent showing an
eutrophication phenomena. The harbour is characterized by high
nutrient load particularly phosphate, nitrtate and ammonia. Its oxygen
content shows a wide variations between surface and near bottom water
layer. The amount ofdissolved organic matter and suspendedparticles
are also high. As a result of excessive nutrient impact, the harbour
sustained high density of phytoplankton attaining an average of4.1 x
106 unit. 1-1 at surface layer. The community was characterized by the
dominance ofeutrophication tolerant algal species such as Skeletonema
costatum, Rhizosolenia jragilissima and R. delicalula.
For over all analysis ofeutrophication phenomenon in the Eastern
Harbour, a stastical regression model describing the dependence of
phytoplankton standing crop on the level of the most important
environmentalfactor was stablished and discussed.