| dc.description.abstract | Sequestering carbon (C) into stable soil
pools has potential to mitigate increasing atmospheric
carbon dioxide concentrations. Carbon accrues in
grassland soil restored from cultivation, but the amount
of physically protected C (here measured as microaggregate-within-macroaggregate C) and predominant
mechanisms of accrual are not well understood. We
modeled the rate of physically protected carbon
accrued in three mesic temperate perennial restored
grasslands from cross-continental regions using datasets with a wide range of restoration ages from
northeast Kansas, USA; southeast Nebraska, USA;
and northeast Free State, South Africa. Further, we investigated major controls on the amount of physically protected C in each site using structural equation
modeling. Variables in the structural equation model
were root biomass, root C:N ratio, soil structure
(indicated by bulk density, percent of macroaggregates
on a per whole soil mass basis, and percent of
microaggregate-within-macroaggregates on a per
macroaggregate mass basis), microbial composition
(indicated by microbial biomass C, total phospholipid
fatty acid [PLFA] biomass, and PLFA biomass of
arbuscular mycorrhizae fungi [AMF] biomass), and
microaggregate-within-macroaggregate C on a per
whole soil mass basis. | en_US |
