Data analyses

Two-way analysis of variance was used to determine significant effects between treatments for the response variables. Response variables were total density, species richness (R), species diversity (H' ), evenness (E) and Sorenson's qualitative similarity index (S) to above-ground vegetation at the donor sites. Species richness was calculated as the total number of species in each donor site and each replicate at the receiver site. Species richness excluded unidentified individuals (i.e. Salix and Carex). Diversity was calculated using the Shannon-Wiener index and evenness was calculated using the formula E = H'/log^R (Magurran, 1988). Sorenson's similarity index was calculated using the formula S = 2 x N/(2 x N + R1 + R2), where N = number of species found in both sites, and R1 and R2 are species richness in donor site and receiver site, respectively. Response variables that did not meet homogeneity of variances were log-transformed or square-root-transformed. When transformations did not improve heterogeneity of variance a non-parametric alternative, the Scheirer-Ray Hare test, was conducted (Scheirer et al., 1976). A P value of 0.05 was used to detect differences between donor soil treatments and a P value of 0.10 was used to compare application depths.

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