257-12 Soil Nitrate Retention and Nitrous Oxide Emissions Increase When Organic Fertilization Practices Are Amended with Biochar.

Poster Number 339

See more from this Division: ASA Section: Environmental Quality
See more from this Session: Agricultural Practices to Improve Nitrogen-Use Efficiency and Mitigate Greenhouse Gas Emission: III (includes student competition)
Tuesday, November 4, 2014
Long Beach Convention Center, Exhibit Hall ABC
Share |

Nicole Niehues1, David Smart2 and Christine M. Stockert2, (1)Soils and Biogeochemistry Graduate Group, University of California-Davis, Davis, CA
(2)Viticulture and Enology, University of California, Davis, Davis, CA
Poster Presentation
  • SSSA_poster_NNIEHUES_FINAL.pdf (1.1 MB)
  • The interations between biochar (pyrolyzed biomass) and organic fertilization practices on greenhouse gas (GHG) emissions and mineral N in perennial agroecoystem soils have not been credibly studied. Biochar was added to two organic fertilization treatments: a cover crop and a grape pomace manure compost in a conservation-tilled vineyard (Cabernet Sauvignon, Vitis vinifera) in Oakville, CA. Soil gas emissions (N2O-N and CO2-C), mineral N content (NO3-N, NH3-N) and gravimetric water content results were compared to controls as well as to conventional methods immediately following and between precipitation events. Treatments were established in February 2013 and arranged in a split-plot randomized complete block design. Significantly higher soil NO3-N peak concentrations as well as lower N2O(g) flux rates were observed in the cover crop and compost treatments that contained biochar compared to the controls, but not in the no-N input conventional treatment containing biochar. There were no significant differences in CO2 flux, NH3-N (measured as NH4), or gravimetric water content between biochar amended and un-amended plots within fertilization treatments. Our data suggest that biochar retains nitrate through sorption which could be available to microbes, enhancing denitrification potential which could explain higher N2O (g) fluxes after soil wetting in biochar treatments.
    See more from this Division: ASA Section: Environmental Quality
    See more from this Session: Agricultural Practices to Improve Nitrogen-Use Efficiency and Mitigate Greenhouse Gas Emission: III (includes student competition)