SPADA Draft Documents

drying oven (105-110ºC) for at least 18 h and then allowed to cool in a desiccator 430 containing calcium sulfate until the soil reaches room temperature. The pans containing 431 subsamples are weighed again and the oven-dry soil mass is determined as the total oven- 432 dry mass (g) minus the pan mass (g). The dry soil fraction is then calculated as: Dry 433 Fraction = oven-dry soil mass / air-dry soil mass. 437 physical, chemical, microbiological, and biochemical (protein and nucleic acid) 438 characteristics and composition. Ideally, subsamples should be archived with associated 439 collection, processing, and characterization metadata in a searchable database. 443 in a closed-lid container for up to five years. Before using the soil for experiments, the 444 soil should be well mixed. Soils should also be re-characterized prior to experiments 445 every 2 years. 449 immediately after collection or as soon as possible after that time. Until usage, the 450 samples can be stored at 4°C in a sealed container to limit microbial activity without 451 having a major impact on the microbial community composition. Studies show that 452 434 435 436 440 441 442 446 447 448 8.8 Soil Storage Once processed, soil samples should be subdivided and stored to preserve the 8.8.1 Air-Dried Soils Soils that are processed by air drying and sieving can be stored at room temperature 8.8.2 Soils for Microbiological and Biochemical Applications Soils that are used specifically for their microbial community should be used either

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