Table 3 Results from Poisson regression models used to test for differences between treatment and referent quadrats in variables related to feral horse impacts at Coyote Canyon, Anza-Borrego Desert State Park, California, USA; Spring 2003.
Covariate | Coefficient (95% CI) | Back-Transformed Coefficient (95% CI) | P-value |
|---|---|---|---|
Number of native species | Â | Â | Â |
Intercept | 1.20 (1.07, 1.33) | 3.29 (2.91, 3.78) | <0.01 |
Soil strength | 0.22 (0.10, 0.33) | 1.24 (1.11, 1.39) | <0.01 |
Soil strength2 | -0.03 (-0.06, -0.01) | -0.97 (0.94, 0.99) | <0.01 |
Dripline | -0.01 (-0.01, -0.00) | -0.99 (0.99, 1.0) | <0.01 |
Quadratb | --- | --- | <0.01 |
   Quadrat 1 (trail) | -0.36 (-0.49, -0.23) | -0.96 (0.61, 0.80) | <0.01 |
   Quadrat 2 (0 m) | 0.21 (0.12, 0.30) | 1.23 (1.12, 1.35) | <0.01 |
   Quadrat 3 (0.10 m) | 0.16 (0.07, 0.26) | 1.18 (1.07, 1.29) | <0.01 |
   Quadrat 4 (1.4 m) | -0.01 (-0.30, 0.27) | -0.99 (0.74, 1.31) | 0.93 |
   Quadrat 5 (Referent) | --- | --- | --- |
Number of macroinvertebrates | Â | Â | Â |
Intercept | -0.71 (-1.04, -0.38) | -0.49 (0.35, 0.68) | <0.01 |
Soil strength | -0.27 (-0.37, -0.17) | -0.76 (0.69, 0.98) | <0.01 |
Day | 0.03 (0.01, 0.06) | 1.03 (1.01, 1.06) | <0.01 |
Quadrata | --- | --- | 0.10c |
   Quadrat 1 (trail) | 0.54 (0.24, 0.85) | 1.72 (1.27, 2.33) | <0.01 |
   Quadrat 2 (0.00 m) | 0.24 (-0.03, 0.51) | 1.27 (0.97, 1.67) | 0.08 |
   Quadrat 3 (0.40 m) | 0.38 (0.12, 0.64) | 1.46 (1.13, 1.90) | <0.01 |
   Quadrat 4 (1.4 m) | NA | NA | NA |
   Quadrat 5 (Referent) | --- | --- | --- |