Suitability of archived soil samples from the National Soil Inventory (BZE) for microbial community analyses

The soil archive that was build up in contest of the first BZE campaign from 2011 to 2017 consists of thousands of samples from sites which are very well characterized. The samples were dried at 40C. No microbiological analyses were conducted during that campaign. The question arises if this valuable archive can still be exploited to gather such information even after some years of storage at room temperature as dried soil samples. Potentially a meaningful microbial community can still be detected or activated after standardized preincubation. Possibly, some microbial groups can be well recovered while others may be damaged during the soil drying and storage, thus e.g. favoring spore-forming microbial groups. Soil samples (a total of 20 samples) from the soil archive were taken and preincubated under two different temperatures (20C and 12C) and incubated for 60 day. The amplicon sequencing of 16S rRNA and ITS1 were analysed to get insights into microbial community composition of these archived soils.