Nitrous oxide emission and soil carbon sequestration from herbaceous perennial biofuel feedstocks

Johnson, JMF; Barbour, NW

HERO ID

5053125

Reference Type

Journal Article

Year

2016

Language

English

HERO ID 5053125
In Press No
Year 2016
Title Nitrous oxide emission and soil carbon sequestration from herbaceous perennial biofuel feedstocks
Authors Johnson, JMF; Barbour, NW
Journal Soil Science Society of America Journal
Volume 80
Issue 4
Page Numbers 1057-1070
Abstract Switchgrass (Panicum virgatum L.) and big bluestem (Andropogon gerdardii Vitman) are potential bioenergy feedstocks. Perennial grasses managed as bioenergy feedstock require nitrogenous inputs, which can cause N2O emission and, thereby, alter their effectiveness to mitigate greenhouse gas (GHG) emission. Few studies have measured N2O emission from perennial grasses managed as feedstock. The objectives of this study were to compare N2O flux and soil organic C (SOC) storage between (i) grasses with legume companion crops or with nitrogenous fertilizer, (ii) two grass harvest times (autumn and spring), and (iii) perennial systems and corn (Zea maize L.)-soybean [Glycine max (L.) Merr.] (C-S) rotation, all without tillage. Nitrous oxide flux was measured from May 2009 to May 2012, and SOC was measured in 2000, 2006, and 2011. Big bluestem-clover (Dalea) and switchgrass-clover treatments had dramatically reduced annual N2O emissions and yield-scaled emissions compared with the respective grasses with urea fertilizer. Cumulative N2O emission was 14 to 40% greater in the big bluestem-spring and switchgrass-spring treatments compared with respective autumn-harvested treatments. The average cumulative emission in fertilized big bluestem and switchgrass treatments (18.5 kg N2O-N ha(-1)) exceeded that of the C-S rotation (12.7 kg N2O-N ha(-1)). The emission factor (EF) for fertilized grasses averaged 2.5%, corn averaged 1.05%, and C-S rotation averaged 1.9%. The SOC storage by perennial grasses was limited to 0 to 5 cm and thus may not be adequate to offset N2O emission. Nitrogen management refinement is recommended for herbaceous perennials to optimize biomass production and minimize N2O emission.
Doi 10.2136/sssaj2015.12.0436
Wosid WOS:000386463000023
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English