Ordinations, which order species/samples along gradients so that objects that are
similar are close together on the gradient, were performed on surface-sediment and rockscrape
diatom data. A Correspondence analysis with Hill’s scaling was used when
examining the rock scrape and surface-sediment samples using both log and square-root
transformations as well as untransformed data, which gave similar results. Principle
component analysis (Hill’s scaling, square root transformation) was used to examine
differences in the diatom assemblages from the rock scrapes. All ordinations were
performed using CANOCO v. 4.5 (ter Braak and Smilauer 2002).
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