Distribution of bacteria in Lake Qarun, AL Fayoum, Egypt (2014 -2015) in relation to its physical and hydrochemical characterization.

The bacteriological monitoring of Lake Qarun water and sediment (aerobic heterotrophs, Staphylococcus sp., Vibrio sp. Aeromonas sp., S. feacalis, E. coli, and total coliform sp.) through the period of study (2014-2015) was carried out. Six common bacterial isolates were fully identified as; Bacillus firmus, Bacillus stratosphericus, Exiguobacterium mexicanum, Stenotrophomonas rhizophila, Halomonas stevensii, and Halomonas korlensis based on partial sequencing of 16Sr DNA. In addition, physical and chemical analyses of Lake Qarun water and sediment (pH, temperature, salinity, dissolved oxygen, BOD, COD, and nutrients) were estimated. The pH varied between 7.08 at sit I and 8.73 at sit V. The temperature varied between 15.6oC at sit VIII and 32.2oC at sit I. The salinity ranged between 3.18% at sit I and 51.72% at sit III. The dissolved oxygen fluctuated between 3.89 md/l at sit VI and 8.96 md/l at sit IV. The BOD ranged between 1.08 mg/l at sit VIII and 6.47 mg/l at sit IV. The COD varied between 11.36 mg/l at sit I and 53.64 mg/l at sit VIII. The phosphate in lake water varied between 1.453.4 μg/l at sit VIII and 498.4 μg/l at sit I. The ammonia ranged between 14.73 μg/l at sit II and 1485 μg/l at sit I. The nitrite varied between 4.10 μg/l at sit IV and 646.5 μg/l at sit I. The nitrate varied between 14.79 μg/l at sit III and 2138 μg/l at sit I. The silicate fluctuated between 894.6 μg/l at sit VI and 4682 μg/l at sit VII.Distribution of bacteria, physical characterization, hydrochemical characterization, Lake Qarun.