TABLE 3.

Individual hydrodynamic variables that explain variation of bacterial community composition and biofilm biomass^a

Parameter, season, and day of growth	Coefficient of determinationb for:
	Global test (adjusted r2)	Depth (cm)	Velocity (cm s−1)	Turbulent kinetic energy (J)	Turbulence intensity (%)
Community composition
Winter
4	0.094*
8	0.137**		0.079**	0.050*
12	0.023
16	0.344**			0.286**	0.046*
20	0.230**
24	0.029
28	0.076
32	0.121**
36	0.152**	0.050*		0.087**
40	0.100*			0.052**
Summer
11	0.107
17	0.112
37	0.140**		0.055**	0.053*
48	0.096
55	0.036
Biomass
Winter
4	0.211*
8	0.273*	0.217**
12	0.240*			0.233**
16	0.386**		0.376**
20	0.105
24	0.210*
28	0.169
32	0.631**				0.542**
36	0.590**	0.121*		0.081*	0.382**
40	0.510**				0.395**
Summer
11	0.324**		0.241**
17	0.508**		0.467**
37	0.025
48	0.596**		0.300**		0.239**
55	0.254*	0.143*

^aThe adjusted coefficient of multiple determination (adjusted r²) of the global test represents an unbiased estimate of the explained variation of the model containing all explanatory variables (35); the most important single variables contributing to the observed variation were identified using the forward selection procedure proposed by Blanchet et al. (9).

^bBoldface indicates statistical significance at a P value of <0.05 (*) or <0.01 (**).