Table 6.

Pearson correlation coefficient between plant morphometric characteristics as given in Fig. 1 and habitat conditions as given in Tables 1 and 2

	pH	Free CO2	NH4-N	PO43-P	Total P
Elodea canadensis
Shoot diameter	–0·75*	0·88**	0·91**
Leaf width	–0·96***	0·86*
Apex d. wt	–0·90**	0·81*
Lagarosiphon major
Shoot diameter	–0·65*
Leaf width		0·84**		0·73*	0·70*
Apex d. wt		0·96***		0·77**	0·68*

Only significant relationships are given. No significant correlations were present for Egeria densa.

*P < 0·05; **P < 0·01; ***P < 0·001.