U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 Fort Collins, Colorado
 close




            Search small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Research Publications at this Location





- ARS National Programs
- Search for a scientific manuscript
- Search for a research project
- ARS Software
- Programs and Projects
- Collaborations
- Subjects of Investigation
- Publications

Title:   Author  item
                                            Stewart, Catherineitem
                                            Follett, Ronalditem
                                            Pruessner, Elizabethitem
                                            Varvel, Garyitem
                                            Vogel, Kennethitem
                                            Mitchell, Robert

                                                         - *Rob*
  Submitted to: Global Change Biology Bioenergy
                                    Publication Type: Peer Reviewed Journal
                                    Publication Acceptance Date: 9/29/2013
                                    Publication  Date: 2/3/2015
                                    Publication URL: http://handle.nal.usda.gov/10113/62133Citation: Stewart, C.E., Follett, R.F., Pruessner, E.G., Varvel, G.E., Vogel, K.P., Mitchell, R. 2015. Nitrogen and harvest treatment effects on soil properties under non-irrigated switchgrass and maize after 9 years:  implications for soil quality  . Global Change Biology Bioenergy. 7,288-301. DOI:10.1111/gcbb.12142.Interpretive Summary:
                                Technical Abstract: Switchgrass (Panicum virgatum L.) is a perennial, cellulosic biofuel feedstock capable of growing under a wide variety of climatic conditions on land marginally suited to cultivated crops.  Despite greater switchgrass root production compared to maize, researchers observed similar soil C sequestration rates after 9 years in a non-irrigated study evaluating N fertilizer and harvest management treatments on switchgrass (harvested at Aug. and Oct.) and no-till maize (with and without stover removal) (Follett et al. 2012). To quantify the form of switchgrass (Cave-in-Rock) and maize-derived organic C we sampled these plots to a depth of 150 cm in 2007 and fractioned the soils into labile (POM) or stable (silt+clay) soil fractions, and natural abundance 13C. We then assessed plant biomarkers through the profile using cupric oxide extraction and pyrolysis-GC/MS.  Through the entire 0-150 cm profile, switchgrass had greater root biomass and a greater root C:N ratio than maize.  Both the POM and silt+clay fractions in the 0-30 cm depth incorporated the higher switchgrass C:N ratio, suggesting that root-derived contribution to SOM under switchgrass may derive directly from lignin rather than root exudates. Lignin biomarkers under maize were more decomposed than under switchgrass, reflecting greater root turnover. These results illustrate complex, plant-specific interactions of nitrogen fertilization and harvest timing on root biomass and soil fraction C.


Return to top


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov