16S bacterial sequences from a soil community in marginal lands with or without switchgrass cultivation Metagenome

Switchgrass (SG; Panicum virgatum L.) is a perennial C4 grass native to the tallgrass prairies and a most promising feedstock in the U.S. for bioenergy production. SG has been shown to input carbon into the soil and thus has the potential to increase C sequestration. However, to fully evaluate the sustainability of SG-based biofuel production, it is crucial to understand the impacts of SG establishment on biotic/abiotic characteristics of nutrient-poor soils. Here, we aim to characterize the ecosystem-scale consequences of SG cultivation in comparison with native annual grassland fallows (FL) at two field sites (designated Sandy loam-SL and Clay loam-CL) in Oklahoma that are low in N and P nutrient availability. We hypothesize that SG sustainability relates to improvements of soil quality mediated by its influence on the soil microbial communities and the activation of beneficial plant-microbe interactions. This will ultimately result in measurable effects on key ecosystem functions like C sequestration and greenhouse gas (GHG) mitigation. During the first two growing seasons, these four plots were monitored monthly. We measured topsoil chemistry, GHG fluxes (CO2 and CH4), and characterized microbial communities using 16S rRNA high-throughput sequencing. GHG concentrations were measured using cavity ring-down spectrometry (i.e. Picarro G2508 analyzer).