Ecological Studies on Nitrogen Cycle Bacteria in Lake Manzala, Egypt

Abstract

S ix stations were chosen to represent the different micro-habitats along the southern part of Lake Manzala. In addition, two main drains, Bahr El-Baqar and Hadous were represented. Water and Bottom sediments were collected through four successive seasons (Autumn 1999-Summer 2000) for physico-chemical and bacteriological analyses. The results showed that water temperature recorded the lowest value during Winter, while it recorded the highest during Summer with an annual amplitude 14.8°C. The Lake is shallow with a depth ranging from 0.85-L31 m. The pH values were in the alkaline side. The water transparency fluctuated from 19.5-325 cm. The organic matter and organic carbon ranged from 5.28-8.71% and 3.06-5.06%, respectively. Bacteriological analysis showed that the highest counts of the studied bacteria were recorded in Bahr El-Baqar and Hadous Drains compared with Lake Manzala' stations.Conversly , the lowest counts of nitrifying bacteria were recorded in Bahr El-Baqar Drain and its discharge points. 264 Saleh A. Rabeh fish and an internationally important wintering area for waterbirds and staging area for migratory birds. Accordingly, the eastern part of the Lake (Ashtum El-Gamil) was declared as a Natural Protectorate in June 1988 fMeininger and Atta. 1990). Nitrogen is a vital clement in aquatic systems, accordingly, the nitrogen cycle occupies an important position among the biological processes acconplished in waters. On the other hand, distortions in the nitrogen cycle, resulting in the accumulation of certain toxic compounds, are one of the major causes of pollution (Rabeh, 1W3, 1996). Although considerable work was done on the role of bacteria in nitrogen cycle in Egyptian soils (

Physicochemical and microbiological studies of River Nile water in Sohag governorate

“…The increase in NO 2 during hot season due to the decomposition of organic matter and presence of nitrozomonas bacteria that oxidize ammonia to nitrite (NO 2 -). Our results were in accordance with Rabeh (2001).…”

Quantitative and Qualitative Studies on the Bacterial Microflora of Some Fish Farms in El- Fayoum Governorate, Egypt

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