The soil water content was maintained at 60% of
WHC at the onset of the experiment and this level was maintained
by periodically weighing the containers (at each sampling day).
The moist soil mixtureswere transferred into plastic containers, tapped
and patted to produce a consistent bulk density (~1.2 g cm−3) across
the C addition treatments. We set up each experimental unit in 1.2 L
sealed plastic containers, which held three small containers: a 200 mL
container with the soil mixtures, a 70 mL jar containing NaOH (2.5 M)
to capture CO2 emanating from soil mixtures and a 70 mL jar with
40 mL of DI water as a humidity control.