Qualitative and quantitative evaluation of the ciliated protozoa in the middle northern coast of Egypt

Protozoa play an important role in the different aquatic food webs. The main objective of this study is to identify the most abundant types of the ciliated protozoa at sampling stations extending along the middle northern coast of about 135 Km in Egypt . Three different classes of ciliated protozoa were detected at three sampling stations. These classes comprised seven subclasses which include 13 different orders. These orders were represented by more than 79 ciliate species. The numbers of the ciliate species    at western Alexandria sampling station were 78, those of El-Hamaam achieved 70 and that of Sedi-A. Rhman reached 66 species only. The highest ciliate numerical densities were detected within class kinetofragminophora, followed by Oligohyminophora and then  Polyhyminophora in the latter two stations, while those of Alexandria proved that Oligohymenophora  exceeds  the other two classes.
Data of the present study illustrated that the level of p < sup>H is slightly alkaline (7.6-7.93),  salinity is 8.2-12.3‰, water temperature is 11.3-2 7.4 ^oC, turbidity is 21.5-50.4 NTU, POC is 0.85 – 1.4 mg/L and dissolved oxygen is 6.3-7.8 mg/L. On the other hand, nutrient concentrations in that region of the Mediterranean sea are 2.9-7.4 ug/L for Ch-a  and  0.21 - 0.61,  0.60 - 0.92,  0.019 -0.078 mg/l  for  silicate, total  nitrates and total phosphates, respectively. Accordingly, it appears that these stations are more or less eutrophic particularly those of Alexandria followed by El-Hamaam and then Sedi-A.Rhman. Simultaneously, the nutrient concentrations of the present investigation are mostly higher as compared with those of the other studies. Comparing the numerical densities of both aquatic and bottom ciliated protozoan organisms belonging to the different classes at those three sampling stations proved that the  ciliates inhabiting the sand grains of the latter are much higher than those of the former one by three to six times.