Assess fate of plant-originated C and N - contribution of switchgrass to soils with contrasting pore size distributions
EMSL Project ID
50981
Abstract
The CO2 and N2O emissions from agricultural soils are an important component of global greenhouse gas emissions, but are hard to accurately estimate. The primary cause is high spatial and temporal variability of gas fluxes. In this study, we evaluated the role of the decomposition of labile organic matter in fostering microbial metabolism for CO2 and N2O production. As the decomposition of fresh organic matter is transitory in nature we propose that it may have a strong influence on hotspots and hot moments N2O production. To evaluate the role of plant decomposition on CO2 and N2O production we used soil microcosms cultivated with switchgrass (Panicum virgatum L..) in carbon and nutrient-poor soil within a greenhouse. Plants were provided with a nutrient solution (N, P, K) but with 15N -enriched for the tracer experiment and were subjected to 13C- CO2 labeling. When the 15N content in the plants from the 15N labeled microcosms reached 5 to 8 atom %, plants and roots outside the container from all microcosms (labeled and non-labeled) were cut and the microcosms were incubated to follow the decomposition process. Our main objective to evaluate the fate of plant N and C in using 15N and 13C as tracers and, especially, to assess microbial pathway of CO2 and N2O production. In this our request to EMSL we are asking for preliminary analyses of microbial biomass extractions for 15N and 13C.
Project Details
Project type
Limited Scope
Start Date
2019-10-01
End Date
2019-12-01
Status
Closed
Released Data Link
Team
Principal Investigator