454 GS FLX Titanium sequencing
DNA was extracted from 0.5 g soil samples and a 700 bp fragment of the V3 - V5 18S rRNA operon was amplified in triplicate from each soil sample using the PCR primers EK448F (5�-CTGAYWCAGGGAGGTAGTRA-3�) and EUK1134R (5�-TTTAAGTTTCAGCCTTGCG-3�).