Litter Quality of Populus Species as Affected by Free-Air CO₂ Enrichment and N-Fertilization

Table 1

Explained variance in litter sample chemistry by the four first Factors (n = 24).

Factor	Eigen value	% Total variance	Cumulative Eigen value	Cumulative Explained variance %
1	29.5	20.0	29.5	20.0
2	19.7	13.4	49.2	33.5
3	18.2	12.4	67.4	45.8
4	14.8	10.0	82.2	55.9