Biplot representation of the ionome results. The length of each eigenvector is proportional to the variance in the data for that element. The angle between eigenvectors represents correlations among different elements. Three groups of elements (circled, and denoted I, II, and III) show strong positive correlations.
Eide et al. Genome Biology 2005 6:R77 doi:10.1186/gb-2005-6-9-r77