Ranking and separation into homogenous subsets using Scheffé’s test of tested preservation conditions based on average log transformed culturability data.

aGroups A & B and B & C are homogenous subsets (no significant difference). Members of group A are significantly different from members of group C (p-value<0.05). bAverage mean culturable log drop (compensated for missing values). cIncreasing culturable log drops from top to bottom.