Research purpose: To assess legacies of previous nitrogen-fertilization in plant and soil carbon and nitrogen pools.
Location of sampling: Belowground Plot Experiment.
Frequency of sampling: Combustible aboveground litter were collected approx. 1 month prior to the prescribed fire in 2021. Shoots, roots, litter, and soil for carbon and nitrogen stock were collected in September 2021. Shoots and litter are aboveground plant biomass collected for PBB01.
variable measured: Litter biomass, accumulated plant biomass, total carbon and nitrogen.
field methods: Field and lab methods are identical to those for PBB01 for aboveground plant biomass collection. Soil and roots were collected from four 5 cm diameter, 15 cm depth cores from each plot, or 1 from each sub-plot. Roots were extracted as soil was sieved through 4 mm. Roots from each core were kept separately, while soil was combined as plot composites.
quality assurance: Total carbon and nitrogen were quantified using thermal conductivity, Standard quality control.
instrumentation: Litter biomass, root, and soil: FlashEA 1112 NC Analyzer, Accumulated plant biomass: LECO TruSpec CN Combustion Analyzer.