Detection Of Microbial Indicator In The Surface Water Of Huaihe River

Objective:Huaihe River is the main source of water in many cities in central China. The riverquality is closely related to the life of the residents in this watershed. This study aims toinvestigate the microbial pollution status of surface water in Huaihe River and thespatial-temporal distribution of microbial indicators. The study will provide the guidancefor pollution control of Huaihe River and the basic data for revising environmental qualitystandards for surface water in China.Method:We collected water samples from the shore and the middle of the Huaihe River in5cities in August2010(high flow period) and December2010(low flow period) andexamined the five indicator bacteria (total coliforms, total bacterial counts, fecal coliforms,Escherichia coli and enterococcus) and the four pathogens (E. coli O157, Salmonella,Vibrio and Shigella) in water samples.Result:1. The total coliform counts were found in the range of1.5×10~3to2.8×10~4CFU/100ml and0.5×10~3to1.95×10~4CFU/100ml, during periods of high and low flow, respectively.The total bacterial counts were found in the range of3.3×10~4to4.85×10~5CFU/100ml and 1.3×10~4to3.55×10~5CFU/100ml during periods of high flow and low flow, respectively.Compared to period of low flow, the levels of total coliform counts and total bacterialcounts were significantly increased during period of high flow (P<0.05). The maximum oftotal coliform counts and total bacterial counts appeared in Bengbu City regardless of highor low flow period. The total coliform counts and total bacterial counts are positivelycorrelated (P<0.01). The both types of microbial indicators are also positively correlatedwith water temperature (P<0.05).2. Fecal coliform counts were found in the range of3.5×10~2to4.0×10~3CFU/100mlduring period of high flow with highest value in Huainan City. Data of low flow period areunviable.3. The Escherichia coli and enterococcus were detected during periods of high andlow flow. No significant difference in Escherichia coli detection between high and lowflow period was found. The enterococcus detection during period of high flow wassignificantly higher than low flow (P<0.01).4. Of four pathogens examined, only Vibrio was detected in the water samples fromthe shore of the river in Huainan City during periods of high flow.Conclusion:The microbial pollution of water in Huainan and Bengbu cities is more serious thanother cites along Huaihe River and the prevention and control measure are needed. Thespatial-temporal distribution of microbial indicators can be presented.