TABLE 2.
Growth and decay rates of FIB and MST markers in cow pats (n = 18)a
| Organism or genetic marker | Treatment | Growth rate (β1) | Decay rate (β2) | T90 (days)b | T99 (days)b | Model r2 |
|---|---|---|---|---|---|---|
| Escherichia coli | Unshaded | 0.881* | −0.297* | 7.75 | 15.51 | 0.82d |
| Shaded | 0.0544 | −0.176 | 13.08 | 26.16 | 0.82d | |
| EPA-EC23S | ND | −0.0621 | 37.08 | 74.15 | 0.80 | |
| Enterococcusc | NA | −0.163 | 14.13 | 28.25 | 0.76 | |
| Entero1c | NA | −0.0434 | 53.06 | 106.12 | 0.61 | |
| CowM3c | NA | −0.126 | 18.27 | 36.54 | 0.69 | |
| Rum-2-bacc | NA | −0.111 | 20.74 | 41.48 | 0.74 | |
| GenBacc | NA | −0.128 | 17.99 | 35.97 | 0.74 |
a
Log concentrations were modeled within the general linear model framework. Asterisks indicate statistical significance between the shaded and unshaded treatments (P < 0.05). ND, not determined; NA, not available.
b
Derived from decay rate (β2).
c
Since shading had no effect on decay rates, decay rates are not presented as a function of treatment.
d
The model includes shaded and unshaded treatments, since it was a significant term.