Effects of Crop Rotation and Grazing in an ICLSs on Greenhouse Gas Emissions in Northern Great Plains.

Poster Presentation at the MANAGING GLOBAL RESOURCES FOR A SECURE FUTURE

2017 Annual Meeting | October 22-25 | Tampa, FL

Section:  Soil Carbon and Greenhouse Gas Emissions General Poster I

Effects of crop rotation and grazing in an ICLS on greenhouse gas emissions in Northern Great Plains

Liming Lai¹, Navdeep Singh¹, Hanxiao Feng¹, Douglas Landblom², Songul Senturklu^2,3, Kris Ringwall², and Sandeep Kumar¹

¹ Department of Agronomy, Horticulture and Plant Science, South Dakota State University,   

  Brookings, South Dakota 57007, USA

² Dickinson Research Extension Center, Dickinson, North Dakota, 58601, North Dakota State    

  University, Fargo, North Dakota 58108 USA

³ Department of Animal Science, Çanakkale Onsekiz Mart University, BMYO, Çanakkale, Turkey

Presenter: Liming Lai (Liming.Lai@sdstate.edu)

ABSTRACT

Integrated crop-livestock system (ICLS) is an alternative that alleviates some of the environmental problems resulted from intensification of crops and livestock. However, little is known about the effects of ICLS on soil surface greenhouse gas (GHG) emissions in Northern Great Plains. The objective was to monitor soil surface GHG fluxes: carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O) to assess the impacts of crop rotation and grazing in an ICLS on the environment. The experiment was a randomized complete block design with 3 replications at Dickinson Research Extension Center ranch located southwest of Manning, North Dakota. The crop rotation treatment included (i) continuous spring wheat (Triticum aestivum L.) (control), (ii) sunflower (Helianthus annuus L.)-spring wheat (Triticum aestivum L.)-cover crop-corn (Zea mays L.)-field pea (Pisum sativum L.) & barley (Hordeum vulgare L.), (iii) spring wheat-cover crop-corn-pea & barley-sunflower, (iv) cover crop-corn-pea & barley-sunflower-spring wheat, (v) corn-pea & barley-sunflower-spring wheat-cover crop, and (vi) pea & barley-sunflower-spring wheat-cover crop-corn. The cover crops from September to June were winter triticale (Triticosecale Wittm.) and hairy vetch for hay. A 7-specie cover crop in fall and winter was for cow winter grazing. The preliminary results in 2016 indicated that annual average soil surface N₂O fluxes ranged from 2.74 to 4.75 g ha^-1 d^-1 and highest fluxes were found in control. The rotation did not significantly impact the N₂O fluxes, but grazing significantly impacted N₂O emission. The emission was significantly higher in grazed plots (5.73 g ha^-1 d^-1) than that in ungrazed plots (2.98 g ha^-1 d^-1). The rotation and grazing treatments did not impact CO₂ and CH₄ fluxes. The soil CO₂ fluxes had a downward trend over time[DL1]  with decreases of temperatures.

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 [DL1]Difficult to understand this statement. Can you explain "time" and the relationship to GHG fluxes, especially considering the previous statements.