In this corpus, Procrustes analysis (also called Procrustes superimposition or Procrustes alignment) is used to test whether one multivariate configuration, such as a community ordination, lines up with another, such as a physical sampling grid or a paired data layer. 1,2
Uses in the corpus
SSO sediment communities versus the physical well grid
Across the 9 sso wells (3×3 grid, ~6 m span), sediment-associated communities show significant distance-decay of similarity by mantel-test (Spearman ρ = 0.323, p = 0.029, 9,999 permutations). The nmds ordination fits well (stress 0.067), but Procrustes analysis finds only marginal correspondence between the community ordination and the physical grid (m² = 0.379, p = 0.080). This Procrustes result does not reach the conventional p < 0.05 threshold, so the grid-shaped arrangement of the community ordination is weaker evidence than the Mantel distance-decay signal from the same nine wells. See SSO Subsurface Community Ecology — Spatial Structure, Functional Gradients, and Hydrogeological Drivers. 1
The project’s figure procrustes_overlay.png is a Procrustes superimposition of the community ordination onto the well grid. It shows directly how the ordination positions line up with grid geometry. 1
Harvard Forest DNA versus RNA functional pools
At harvard forest, the notebook 04_dna_vs_rna_divergence.ipynb ran a paired n=25 permanova on DNA and RNA KO (KEGG Orthology gene-family) pools, together with a Procrustes alignment test. The test asks whether the metagenomic and metatranscriptomic functional configurations correspond. The supplied evidence records only that the test was run and its sample size; it does not give the Procrustes statistic or its significance. See Harvard Forest Long-Term Warming — DNA vs RNA Functional Response. 2
Evidence strength
The only Procrustes outcome reported in the assigned evidence is the marginal SSO grid correspondence. It comes from a single small grid of wells and should not be read as an established spatial structuring of community composition. 1
The Harvard Forest use documents that the method was applied, not what it found. 2