Ecological Archives E089-200-A3

H. M. Valett, S. A. Thomas, P. J. Mulholland, J. R. Webster, C. N. Dahm, C. S. Fellows, C. L. Crenshaw, and C. G. Peterson. 2008. Endogenous and exogenous control of ecosystem function: N cycling in headwater streams. Ecology 89:3515–3527.

Appendix C. Principal components analysis (PCA) of seasonal samples in structural space.

FigC1
 
   FIG. C1. PCA of seasonal samples in structural space. Symbols are streams in forested (ORNL: East Fork Walker Branch, filled square; West Fork Walker Branch, open square;CWT: Hugh White Creek, open diamond; Snake Den Branch, filled diamond) and open-canopied (Gallina Creek, filled circle; Rio Calaveras, open circle) catchments. Sites were ordinated based on independent variables used to address metabolic and biogeochemical responses including: stream discharge, velocity, depth, width, cross-sectional area, NO3-N, SRP, temperature, and PAR. Ordinatioin explained 79% of variation over three axes.

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