Soil microbe biomass (DP1.10104.001)

Soil sampling occurs annually at a minimum of one site per domain and once (sites with short growing seasons) to three times per year (sites with longer growing seasons), with collections occurring at every sampled site during the historic peak in vegetation greenness. Three pre-determined, randomly assigned locations are selected for each sampling event within each of 10 plots distributed throughout a site; sampling locations within a plot are not re-sampled. Soil samples are collected to a maximum depth of 30 cm, with organic and mineral soils sampled separately. The same samples are used for measurement of soil physical and chemical properties to maintain temporal and spatial connectivity. Subsamples of homogenized soil are either sieved (mineral soils), or picked of coarse debris such as rocks, roots and organic material (organic soils) and 5-10g are transferred to cryo-safe vials. The samples are frozen and shipped on dry ice to an analytical facility, where freeze-drying, PLFA extraction and GC analysis is performed. Laboratory data are passed through the NEON automated ingest process, undergo additional QAQC testing, and quality-checked data are published on the NEON data portal. Instrumentation: