Succession in subtidal macrofouling assemblages of a Patagonian harbour (Argentina, SW Atlantic)

Table 2 Summary of multivariate PERMANOVAs of the effect of substratum orientation and succession length or starting season on assemblage structure

Source	df	MS	pseudo-F	P
Succession analysed at quarterly intervals
Surface orientation	1	27857.2	29.29	0.001
Succession length	3	4919.7	5.17	0.001
Surface orientation × succession length	3	4291.3	4.51	0.001
Residual	24	951.2

	t	P
Pairwise a posteriori comparisons
Lower surfaces
3 months versus 6 months	2.74	0.012
3 months versus 9 months	2.56	0.010
3 months versus 12 months	3.92	0.002
6 months versus 9 months	1.73	0.048
6 months versus 12 months	1.48	0.124
9 months versus 12 months	1.98	0.025
Upper surfaces
3 months versus 6 months	1.68	0.080
3 months versus 9 months	3.51	0.003
3 months versus 12 months	1.54	0.130
6 months versus 9 months	1.97	0.063
6 months versus 12 months	1.01	0.374
9 months versus 12 months	1.26	0.239

Source	df	MS	pseudo-F	P
1-year-old assemblages starting at different seasons
Surface orientation	1	23564.2	29.80	0.001
Starting season	3	2572.3	3.25	0.008
Surface orientation × starting season	3	2265.4	2.86	0.009
Residual	24	790.8

	t	P
Pairwise a posteriori comparisons
Lower surfaces
Summer versus autumn	1.94	0.048
Summer versus winter	0.86	0.529
Summer versus spring	0.74	0.649
Autumn versus winter	2.15	0.026
Autumn versus spring	2.17	0.017
Winter versus spring	0.70	0.711
Upper surfaces
Summer versus autumn	1.30	0.219
Summer versus winter	1.42	0.144
Summer versus spring	1.98	0.039
Autumn versus winter	3.53	0.004
Autumn versus spring	5.30	0.002
Winter versus spring	1.24	0.211

Significant results in bold
df Degrees of freedom, MS mean square, F F ratio, P Monte Carlo probability values associated with F values, t multivariate version of the t-statistics (based on distances)

ISSN: 1438-3888