Table 2.

Variance components model of shoot Si concentrations, based on a meta-analysis of primary data from 125 studies, contained in 54 papers in the primary literature, in which Si concentrations of leaf or non-woody shoot tissue were reported

Variance component	Variance	s.e.	% of total variance
Study	0·815	0·128	16·0
Group	3·409	2·204	66·9
Group/order	0·019	0·032	0·4
Group/order/family	0·127	0·044	2·5
Group/order/family/genus	0·102	0·039	2·0
Group/order/family/genus/species	0·072	0·044	1·4
Residual variance model	0·550	0·040	10·8

Each study included at least two plant species growing in the same environment, and each study contained at least one species in common with another study.