الفهرس 
Materials and methodsOnly 14 pages are availabe for public view
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Abstract
One of the most important living organisms in the aquatic ecosystem are phytoplankton. Phytoplankton are microscopic algae that occur in unicellular, colonial, or filamentous forms. Phytoplankton abundance in a water body reflects the average ecological condition and, therefore, it may be used as an indicator of water quality. They are an excellent ecological indicator at the species level, sensitive to a number of environmental variables including light, temperature, inorganic nutrients (carbon, phosphorus, nitrogen, silica, and iron), organic carbon, organic nitrogen, oxygen concentrations, pH and salinity.
The present thesis deals with the study of changes in number and type of algae and its relation to the physico-chemical nature of the River Nile. Samples were collected from the intake of some water treatment plants in Fayoum governorate, samples were collected from seven sampling sites to a large extent covering the stream of River Nile branches in Fayoum governorate, and hence the work plane was as follows:
Sub surface water samples were collected at monthly intervals for one year (October 2011 to September 2012) to follow physic-chemical and biological changes that may occur on the River Nile water. Water samples were collected from specific sites that were chosen to cover the study area of the River Nile at Fayoum governorate. The sampling sites were as follows:
Site 1: Intake of New El-Azab water treatment plant.
Site 2: Intake of Old El-Azab water treatment plant.
Site 3: Intake of Quhafa water treatment plant.
Site 4: Intake of Abo-Gandir water treatment plant.
Site 5: Intake of El-Rayan water treatment plant.
Site 6: The mixing point on Bahr El-Banat.
Site 7: Intake of Tamia water treatment plant.
The results obtained in this study can be summarized in the following points:
Physico-chemical changes of River Nile water:
• Physical characteristics: River Nile water temperature ranged between (14.3-330C), the water pH was always in the alkaline side its results were between (7.3- 8.2). Turbidity values ranged between (7.3- 60.1) in sites that receive water from a branch of the River Nile (S1, S2, S3, S4, S5 and S6), while it ranged between (3.2- 13.7) in S7 that receive water directly from the River Nile.
• Indicator of pollution: Dissolved oxygen values ranged between (4.1- 10.2) mgO2/L, while chemical oxygen demand results ranged between (3- 16.5) mgO2/L which exceed the limit of the Egyptian ministry of health. This indicates a presence of pollution.
• Nutrients: Include nitrogen group (Ammonia, Nitrite and Nitrate), Phosphorus, Silica, Iron and Manganese, the results were as follows:
a. Nitrogen group: ammonia, nitrite and nitrate results ranged between (0.06- 0.89) mg NH3 /L, (0.01- 0.72) mg NO2/L and (0.45- 13.3) mg NO3/L respectively.
b. Phosphorus: results of total phosphorus ranged between (0.03-0.77) during the period of study.
c. Silica: dissolved silica is an important nutrient for silica wall formation of diatoms (dominate phytoplankton assemblages). Concentration of dissolved Silica ranged between (0.21- 9.88) mg SiO2/L. The lowest values were associated with the maximum growth of diatoms.
d. Iron: (Micronutrient element) its values ranged from 0.16 to 5.53mg/L.
e. Manganese: (Micronutrient element) its values ranged from 0.01 to 0.45 mg/L.
• Heavy Metals: Metals of arsenic, beryllium, cadmium, lead and zinc not detected in all samples collected.
Biological changes of River Nile water
Algae count, algae identification and chlorophyll content were determined.
The total algal count ranged between (394- 16344) Org./ml. Five algal groups were found during the study period and their counts ranged between (0-27) Org./ml, (0-38) Org./ml, (0-434) Org./ml, (57-1053) Org./ml and (280-15863) Org./ml for Dinophyta, Euglenophyta, Cyanophyta, Chlorophyta and Bacillariophyta respectively.
During the study 54 species were observed 22 of them belonging to Chlorophyta, 18 belonging to Bacillariophyta, 10 belonging to Cyanophyta, 3 belonging to Euglenophyta and only one for Dinophyta.
The species were:
Dinophyta
Peridinium cinctum
Euglenophyta
Euglena sanguine / Phacus triqueter / Tracheolomonace armata
Cyanophyta
Oscillatoria mougeotii / chrococcus turgidus / Merismopedia glauca / Microcystis aeruginosa / Anabaena conistricta / Coelosphaerium kuetzingianum / Gomphaspheria lacustris / Gleocapsa sanguine / Spirulina abbreviate / Cylindrospermum stagnale
Chlorophyta
Actinastrum hantzschii / Ankistrodesmus falcatus / Botryococcus braunii / Closterium pronum / Chodatella cilliata / Coelosterum microporum / Cosmarium bioculatum / Crucigenia rectangularis / Kirchneriella obese / Selenastrum gracile / Staurastrum paradoxum / Tetraedron minimum / Dictyosphaerium ehrenbergianum / Golenkinia radiate / Micracitinum pusillum / Nephrocytium lunatum / Chlamydomonas variabills / Pediastrum simplex / Scenedesmus quadricauda / Ulothrix subtiiissima / Oocystis solitaria / Chlorella vulgaris
Bacillariophyta
Synedra ulna / Melosira granulate / Cyclotella ocellata / Pleurosigma delicatulum / Cocconies placentula / Fragilaria capucina / Navicula cuspidata / Nitzschia linearis / Cymatopleura solea / Gomphonema olivaceum / Pinnularia borealis / Stephanodiscus dubius / Diatoma hiemale / Surirella ovalis / Amphora ovalis / Stauraneis / Cymbella prostrasta / Calonies amphisbaena
Chlorophyll content
Chlorophyll a concentration ranged from 0.2 to17.53 µg/L during the study period.
A general and collective conclusion that we can withdraw from our study, is that:
1-Algal numbers may change in the raw Nile water according to the time and season of the year in addition to the site of sample collection. Therefore, analysis should be conducted over yearly cycles.
2-Dominance and diversity of algal species in aquatic ecosystem specify the quality of the ecosystem to different human uses.
3-Study algal community structure of aquatic ecosystem is a key factor in determining water treatment technology used in Drinking Water Treatment Plant.
4-The presence of different algal groups with high numbers during various seasons in the river Nile has led to a re-evaluation of traditional treatment technologies.