@article{e85f9da3a9184e19afe5f3c671fc463f,
title = "The carbon and nitrogen cycle impacts of reverting perennial bioenergy switchgrass to an annual maize crop rotation",
abstract = "In the age of biofuel innovation, bioenergy crop sustainability assessment has determined how candidate systems alter the carbon (C) and nitrogen (N) cycle. These research efforts revealed how perennial crops, such as switchgrass, increase belowground soil organic carbon (SOC) and lose less N than annual crops, like maize. As demand for bioenergy increases, land managers will need to choose whether to invest in food or fuel cropping systems. However, little research has focused on the C and N cycle impacts of reverting purpose-grown perennial bioenergy crops back to annual cropping systems. We investigated this knowledge gap by measuring C and N pools and fluxes over 2 years following reversion of a mature switchgrass stand to an annual maize rotation. The most striking treatment difference was in ecosystem respiration (ER), with the maize-converted treatment showing the highest respiration flux of 2,073.63 (± 367.20) g C m−2 year−1 compared to the switchgrass 1,412.70 (± 28.72) g C m−2 year−1 and maize-control treatments 1,699.16 (± 234.79) g C m−2 year−1. This difference was likely driven by increased heterotrophic respiration of belowground switchgrass necromass in the maize-converted treatment. Predictions from the DayCent model showed it would take approximately 5 years for SOC dynamics in the converted treatment to return to conditions of the maize-control treatment. N losses were highest from the maize-converted treatment when compared to undisturbed switchgrass and maize-control, particularly during the first conversion year. These results show substantial C and N losses occur within the first 2 years after reversion of switchgrass to maize. Given farmers are likely to rotate between perennial and annual crops in the future to meet market demands, our results indicate that improvements to the land conversion approach are needed to preserve SOC built up by perennial crops to maintain the long-term ecological sustainability of bioenergy cropping systems.",
keywords = "bioenergy, eddy covariance, land use change, soil biogeochemical cycles",
author = "Moore, {Caitlin E.} and Berardi, {Danielle M.} and Elena Blanc-Betes and Dracup, {Evan C.} and Sada Egenriether and Nuria Gomez-Casanovas and Hartman, {Melannie D.} and Tara Hudiburg and Ilsa Kantola and Masters, {Michael D.} and Parton, {William J.} and {Van Allen}, Rachel and {von Haden}, {Adam C.} and Yang, {Wendy H.} and DeLucia, {Evan H.} and Bernacchi, {Carl J.}",
note = "Funding Information: Funding for this work was provided by the DOE Center for Advanced Bioenergy and Bioproducts Innovation (U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research under Award Number DE‐SC0018420). Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the U.S. Department of Agriculture. Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U.S. Department of Agriculture. USDA is an equal opportunity provider and employer. The authors especially thank Mr. Tim Mies and Mr. Trace Elliot for their management of the Energy Farm research facility and their assistance in preparing fields and providing land management advice for this project. We wish to acknowledge the efforts of past postdocs, technicians, and students who have contributed toward measurements and keeping these sites running through their years of operation. We also thank Dr. Peter Isaac and Dr. Cacilia Ewenz from OzFlux and the Australian Terrestrial Ecosystem Research Network—Ecosystem Processes group (TERN‐EP) for their technical support with PyFluxPro. Funding Information: Funding for this work was provided by the DOE Center for Advanced Bioenergy and Bioproducts Innovation (U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research under Award Number DE-SC0018420). Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the U.S. Department of Agriculture. Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U.S. Department of Agriculture. USDA is an equal opportunity provider and employer. The authors especially thank Mr. Tim Mies and Mr. Trace Elliot for their management of the Energy Farm research facility and their assistance in preparing fields and providing land management advice for this project. We wish to acknowledge the efforts of past postdocs, technicians, and students who have contributed toward measurements and keeping these sites running through their years of operation. We also thank Dr. Peter Isaac and Dr. Cacilia Ewenz from OzFlux and the Australian Terrestrial Ecosystem Research Network?Ecosystem Processes group (TERN-EP) for their technical support with PyFluxPro. Publisher Copyright: {\textcopyright} 2020 The Authors. GCB Bioenergy Published by John Wiley & Sons Ltd. This article has been contributed to by US Government employees and their work is in the public domain in the USA.",
year = "2020",
month = nov,
day = "1",
doi = "10.1111/gcbb.12743",
language = "English (US)",
volume = "12",
pages = "941--954",
journal = "GCB Bioenergy",
issn = "1757-1693",
publisher = "Wiley-VCH",
number = "11",
}