Microbial profile and its changing rates of <scp>L</scp>ake <scp>B</scp>urullus, <scp>E</scp>gypt as wastewater receiving body

Abstract

Abstract Understanding the impacts of seasonal variations on fate and distribution of natural and introduced microbes are important for proper public health, risk assessment and water management of Lake Burullus, Egypt (LB) as water receiving body. The effects of mixing processes on microbial loads in Lake and discharged aquacultural wastewater (AQ) and agricultural drainages (AG) were assessed. Microbiological examinations of discharged waters in this study revealed that total bacterial count (TBC), and total coliform count (TCC) were significantly high at P ≤ 0.05 in aquacultural wastewater than both LB and AG. Total fecal coliform count (TFC) and total fecal streptococcus (TFS) were determined and showed that AG has significantly high at P ≤ 0.05 comparing to both LB and AQ. No seasonal differences in‐between all indictors values of LB, while AG wastewater values were mostly higher than both AQ and LB water samples with declining attitude between sampling points. In case of TBC, TCC and TFC, the microbial loads of lake water were highly affected by receiving water but in case of TSF, the water shows no affects. Contrary, for discharged waters, both show reduction in count that is meaning of dilution processes. As excessive discharge of raw wastewater may present a risk related to high increased rate of TBC and TCC in lake water annually by 27.8 and 33.0% at 500 m points, respectively.