Short-term drought response of N 2 O and CO 2 emissions from mesic agricultural soils in the US Midwest

Journal Article · Fri Jul 17 00:00:00 EDT 2015 · Agriculture, Ecosystems and Environment

DOI:https://doi.org/10.1016/j.agee.2015.07.005· OSTI ID:1245480

Gelfand, Ilya ^[1]; Cui, Mengdi ^[2]; Tang, Jianwu ^[3]; Robertson, G. Philip ^[4]

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1. Michigan State Univ., East Lansing, MI (United States). W.K. Kellogg Biological Station and Great Lakes Bioenergy Research Center (GLBRC)
2. Brown Univ., Providence, RI (United States). Dept. of Geological Sciences; The Ecosystems Center, Woods Hole, MA (United States). Marine Biological Lab.
3. The Ecosystems Center, Woods Hole, MA (United States). Marine Biological Lab.
4. Michigan State Univ., East Lansing, MI (United States). W.K. Kellogg Biological Station, Great Lakes Bioenergy Research Center (GLBRC) and Dept. of Plant, Soil and Microbial Sciences

Climate change is causing the intensification of both rainfall and droughts in temperate climatic zones, which will affect soil drying and rewetting cycles and associated processes such as soil greenhouse gas (GHG) fluxes. Here, we investigated the effect of soil rewetting following a prolonged natural drought on soil emissions of nitrous oxide (N₂O) and carbon dioxide (CO₂) in an agricultural field recently converted from 22 years in the USDA Conservation Reserve Program (CRP). We compared responses to those in a similarly managed field with no CRP history and to a CRP reference field. We additionally compared soil GHG emissions measured by static flux chambers with off-site laboratory analysis versus in situ analysis using a portable quantum cascade laser and infrared gas analyzer. Under growing season drought conditions, average soil N₂O fluxes ranged between 0.2 and 0.8 μg N m^-2 min^-1 and were higher in former CRP soils and unaffected by nitrogen (N) fertilization. After 18 days of drought, a 50 mm rewetting event increased N₂O fluxes by 34 and 24 fold respectively in the former CRP and non-CRP soils. Average soil CO₂ emissions during drought ranged from 1.1 to 3.1 mg C m^-2 min^-1 for the three systems. CO₂ emissions increased ~2 fold after the rewetting and were higher from soils with higher C contents. Observations are consistent with the hypothesis that during drought soil N₂O emissions are controlled by available C and following rewetting additionally influenced by N availability, whereas soil CO₂ emissions are independent of short-term N availability. Finally, soil GHG emissions estimated by off-site and in situ methods were statistically identical.

• Research Organization: Univ. of Wisconsin, Madison, WI (United States); Michigan State Univ., East Lansing, MI (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE); USDOE Office of Science (SC), Biological and Environmental Research (BER); National Science Foundation (NSF); Brown Univ., Providence, RI (United States)
• Grant/Contract Number: FC02-07ER64494; AC05-76RL01830; DEB 1027253; DBI-959333
• OSTI ID: 1245480
• Alternate ID(s): OSTI ID: 1438266
• Journal Information: Agriculture, Ecosystems and Environment, Journal Name: Agriculture, Ecosystems and Environment Vol. 212 Journal Issue: C; ISSN 0167-8809
• Publisher: Elsevier
• Country of Publication: Netherlands
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
Soil carbon
Conservation reserve program
N2O methodology
Corn
No-till