Table 2. Three-way PERMANOVA tests for differences in macrobenthic community among stations (St), month (Mt) and bottom type (Bt).

		pr/ab		dbrt		nonTr
source	df	PsF	CV	PsF	CV	PsF	CV
St	4	39.1**	12.1	45.4**	13.0	34.1**	17.8
Mt	1	12.0**	10.4	13.7**	11.0	10.1**	14.8
Bt	1	39.1**	20.9	92.9**	18.7	17.1**	12.4
StxMt	4	4.0**	7.7	4.9**	8.6	6.6**	16.3
StxBt	4	4.0*	4.8	5.1**	5.6	7.8**	11.4
MtxBt	1	2.9*	6.1	5.8**	9.5	5.7**	15.1
Mt x St x Bt	4	1.6	4.9	2.8**	8.2	3.9**	16.6
Res	80		13.9		13.8		21.8
Bt (MtxBt)		all		all		Oct', Jun, Jul, Oct

Tests performed on Bray-Curtis similarity matrices for: presence/absence data (pr/ab), double root transformed (dbrt), and untransformed data (nonTr). Effects of bottom type and MtxBt interaction printed in bold. PsF - PERMANOVA pseudoF, CV - component of variation. Significant effects: * P<0.05, ** P<0.001. Bt (MtxBt) - significant effects in pairwise tests for differences between vegetated and unvegetated bottoms performed separately for five months.