Leavitt, S. W., E. A. Paul, E. Pendall, P. J. Pinter, and B. A. Kimball. 1997. Field variability of carbon isotopes in soil organic carbon. Nuclear Instruments and Methods in Physics Research Section B 123:451-454.
Free-air CO, enrichment (FACE) plant-growth experiments conducted in Arizona have allowed a spinoff isotope tracer experiment (tank CO, is i4C- and i3C-depleted) to follow the input of carbon into soil organic matter pools. Accurate assessment of the ‘“C and 13C inputs to soils by this pathway requires detailed knowledge of the isotopic composition of the soils before the experiments. We have examined the variability of S13C in soil organic matter in 8 experimental plots prior to the beginning of the 1995-96 FACE experiments with wheat. 613C variability was higher immediately after harvest of a previous crop in June, but the plots were much more homogeneous five months later immediately before planting Intervening field management, including disking, plowing and installation of irrigation drip tape likely contributed to mixing the soils.
Download citation to endnote bibtexSign in to download PDF back to index