Forest Floor Variability and Factor Analysis: A Case Study

A case study is presented to illustrate how factor analysis can be used to quantify probable causes of physical and chemical forest-floor variability. Twenty forest-floor variables were examined for a 30 × 30-m sampling plot located within a mature, naturally regenerated conifer stand. "Slough" (the degree of accumulation of decayed stumps, logs, branches, etc.), litter (hardwood- vs. softwood-type in terms of base-status) and insolation (degree of canopy closure) factors appeared to underlie the observed variability pattern. Factor identification was facilitated by the following variable association pattern: (i) total C with total Fe, Al, N, P, K; (ii) total C with LFH-mass and thickness; (iii) water-extractable P with 2 N potassium-chloride-extractable NH4-H; (iv) total and 1 N ammonium-acetate-extractable Ca with pH; and (v) ground cover vegetation density with forest floor moisture content and thickness.