Table 2 Multiple regression summary of model predicting biomineral ureolytic activity

Predictor variables

Estimates

Estimates

Estimates

Estimates

Estimates

Estimates

Intercept

−7.35(−12.80–-1.90)**

−2.18(−6.92–2.57)

− 0.55(−5.05–3.94)

− 0.46(− 5.00–4.08)

−0.56(− 5.12–3.99)

−0.36(− 4.92–4.20)

Annual users per rest area

0.96(0.56–1.37)***

0.57(0.22–0.92)**

0.50(0.17–0.82)**

0.47(0.14–0.81)**

0.49(0.16–0.83)**

0.49(0.16–0.82)**

Intrasystem location: gallery drain

−0.28(−0.62–0.07)

− 0.19(− 0.52–0.13)

−0.15(− 0.51–0.21)

−0.19(− 0.53–0.15)

−0.14(− 0.50–0.22)

Intrasystem location: gallery main drain

1.02(0.61–1.43)***

1.24(0.83–1.64)***

1.26(0.85–1.68)***

1.24(0.83–1.65)***

1.23(0.82–1.64)***

VS/TS (g g^− 1)

0.59(0.21–0.97)**

0.57(0.19–0.96)**

0.58(0.17–0.99)**

0.56(0.18–0.95)**

ureC concentration (copy # g⁻¹ VS)

0.01(−0.02–0.04)

Sampling season

0.01(−0.31–0.33)

Urinal type

−0.12(−0.49–0.25)

Observations

55

55

55

55

55

55

R²/R² adjusted

0.299/0.286

0.595 0.571

0.662/0.635

0.665/0.630

0.662/0.628

0.665/0.631