Evaluating spatial-temporal variations and correlation between fecal indicator bacteria (FIB) in marine bathing...

Area of Science:

• Environmental microbiology
• Marine ecology
• Public health

Background:

• Marine bathing beaches are vital recreational areas.
• Water quality monitoring is crucial for public health.
• Identifying reliable bacterial indicators is essential for assessing fecal contamination.

Purpose of the Study:

• To investigate the distribution and variation of bacterial indicators in a Chinese marine bathing beach.
• To determine the most suitable bacterial indicators for assessing fecal pollution.
• To understand the impact of rainfall and proximity to shore on bacterial levels.

Main Methods:

• Sampling at different water depths during dry and rainy weather.
• Analysis of four bacterial indicators: total coliforms (TC), fecal coliforms (FC), enterococcus (EC), and Escherichia coli (E. coli).
• Statistical comparison of indicator levels and exceedance rates.

Main Results:

• All four indicators exceeded standards at varying frequencies, with EC (38%) and FC (28%) showing higher exceedance rates.
• Bacterial concentrations significantly increased after rainfall events.
• Higher bacterial levels were observed closer to the shoreline, indicating contamination from sewage discharge and runoff.

Conclusions:

• Enterococcus (EC) and fecal coliforms (FC) are recommended as primary indicators for fecal pollution at Chinese marine bathing beaches.
• Water quality is significantly affected by rainfall and proximity to shore.
• Integrated monitoring of EC and FC is advised for effective beach water management.