Figure 2

Relationship of E. coli abundance with environmental and urban infrastructure features (a) Biplot of a principal component analysis including all samples and variables. Sampled sites from San Francisco stream are in purple, Las Piedras stream in green and Santo Domingo stream in blue; (b) Network diagram of correlations with an absolute Pearson’s ρ greater than 0.5. Green edges correspond to positive correlations and red edges to negative ones; The edge width indicates the magnitude of Pearson's ρ. Light-blue circles represent the environmental parameters, purple circles the infrastructure variables and pink circles the abundance of E. coli. LP, Las Piedras stream; SF, San Francisco stream; SD, Santo Domingo stream; DIN, dissolved inorganic nitrogen; SRP, soluble reactive phosphorus; DOC, dissolved organic carbon; DO, dissolved oxygen; T, temperature; Pop, population density; Cond, conductivity. Data analysis performed in R software73. Graphical edition in Inkscape V 0.92.4. Inkscape Project (2020). https://inkscape.org.