Fig. 4

Correlation between environmental parameters and microbial presence. Illustartion of the correlation between environmental factors (temperature and pH) and the presence of Acanthamoeba and K. pneumoniae across the sampled sites. A Box plot of water temperature at different sampling sites. The temperature varied across sites of Meichuan Canal (26–27°C), Midori River (28–29°C), Han River (29–30°C), Liuchuan Canal (29–30°C) and Taichung Park Lake (30–31°C). Black outlines represent sites where neither K. pneumoniae nor Acanthamoeba were detected. Red outlines indicate sites where only K. pneumoniae was detected, while green outlines indicate sites where both K. pneumoniae and Acanthamoeba were detected. B Distribution of K. pneumoniae and Acanthamoeba across different sampling sites in relation to pH levels. Each symbol represents a different sampling point (● Sample 1, ■ Sample 2, ▲ Sample 3). Red markers indicate samples where only K. pneumoniae was detected, while green markers indicate co-detection of both Acanthamoeba and K. pneumoniae. Black markers represent samples where neither microorganism was detected