NITROGEN AND PHOSPHORUS FORMS IN ALEXANDRIA WESTERN HARBOUR

NITROGEN AND PHOSPHORUS FORMS IN ALEXANDRIA

WESTERN HARBOUR

By
R. B. NESSIM
National Institute of Oceanography and Fisheries, Alexandria, Egypt.

Key words :Nitrogen and Phosphorus ratio. Alexandria, Mediterraneall’Sea.

ABSTRACT
The present paper reports the variations offive forms of Nitrogen and
Phosphorus in Alexandria western harbour water. These nutrient fractions
include dissolved organic as well as inorganic andparticulate compounds in
addition to total dissolved and non dissolvedforms.
The mean annual ratiosfor the different N-Forms to the total N-content are
more or less identical to those corresponding P. The dissolved inorganic/total
average ratio is nearly 1:5; while that oforganic/total element is 1:2.
The 1110st abundantfraction oftotalN or P is the total dissolvedform. being
about 2/3 (?fthe total average content. The particulate partltotal ratio did not
exceed 1/3.
The N/P mean ratiosfor the d!Uerentforms are around 50: 1; indicating
that P was the potentially most limiting nutrient for phytoplallktonbiomass
production ill the harbour water.