TABLE 3.

Regressions between T-RFLP principal-component ordination and soil chemistry/N-processing rates^a

Parameter	PC1		PC2
	r2	P	r2	P
Initial NO3 pool (μg/g)	0.749	0.000	0.353	0.006
Nitrification (μg/g/day)	0.419	0.013	0.208	0.044
DNRA (μg/g/day)	0.363	0.025	0.191	0.053
15N2 flux	0.228	0.049	0.026	0.493
Total N gas flux (denitrification)	0.225	0.050	0.025	0.508
15N2O flux	0.185	0.085	0.033	0.440
Initial NH4 pool (μg/g)	0.142	0.124	0.013	0.631
Microbial biomass N	0.073	0.310	0.025	0.504
15N microbial biomass uptake	0.032	0.444	0.001	0.970
Mineralization (μg/g/day)	0.029	0.417	0.104	0.166
NH4 consumption (μg/g/day)	0.001	0.605	0.371	0.004
PC2	0.000	0.830	NAb	NA

^aData are from soil samples collected in the Luquillo Experimental Forest and incubated under four redox regimens. Significant correlations (P < 0.05) are indicated in boldface; those with r² values of >0.2 are underlined. Separate multiple regression was performed for each principal component. All rates were measured over 0 to 24 h following ¹⁵N labeling.