KBS024:Soil Total Carbon and Total Nitrogen on the Main Cropping System Experiment

Soil carbon and nitrogen are presented as % elemental carbon and nitrogen (g C or N / 100 g soil) for the sampling depth of the specific sampling date unless indicated otherwise. Samples were taken with either a 2.5 cm diameter soil corer (sampling by soil depth) or a 10 cm diameter Giddings probe (sampling by soil profile). See Baseline Soil Sampling protocol for general sampling information. For specific sampling details for a particular date, see Soil Sampling Field Log. Soil samples are sieved to 4mm and composited by plot. Soil % elemental carbon and nitrogen values are determined by sample combustion and subsequent TCD gas chromatography, using a Carlo Erba automated CHN analyzer as described in the sampling protocol.