Short‐term grazing of cover crops and maize residue impacts on soil greenhouse gas fluxes in two Mollisols

Abstract

An integrated crop-livestock system (ICLS), when managed properly, can help in mitigating soil surface greenhouse gas (GHG) fluxes, especially carbon dioxide (CO 2 ), methane (CH 4 ), and nitrous oxide (N 2 O). However, the impacts of an ICLS on GHG fluxes are poorly understood. The present study was conducted at two sites (northern Brookings [Brookings-N] and northwestern Brookings [Brookings-NW]) established in 2016 and 2017, respectively, under loamy soils in South Dakota. The specific objective was to evaluate the impact of cover crops (CCs) and grazed CCs under oat (Avena sativa L.)-CCs-maize (Zea mays L.) rotation on GHG fluxes. Study treatments included the following: (a) a legume-dominated CC (LdC), (b) a cattlegrazed LdC (LdC+G), (c) a grass-dominated CC (GdC), (d) a cattle-grazed GdC (GdC+G), and (e) one without CC or grazing (NC). Greenhouse gas monitoring occurred weekly during the growing crop seasons in 2016 and 2017 for Brookings-N and in 2017 and 2018 for Brookings-NW. Data showed that cumulative CO 2 and N 2 Ofluxes at Brookings-N were lower for GdC+G (4042 kg C ha −1 for CO 2 and 1499 g N ha −1 for N 2 O) than for LdC+G (4819 kg C ha −1 for CO 2 and 2017 g N ha −1 for N 2 O), indicating the superiority of GdC+G over LdC+G in reducing GHG fluxes. However, no effect from grazed CC on cumulative CO 2 and N 2 O fluxes were observed at the Brookings-NW site. Cumulative CH 4 flux was not affected by an ICLS at either site.This short-term investigation showed that, in general, CCs and grazing of CCs and maize residue did not impact GHG fluxes.

Grassland conversion to croplands impacted soil pore parameters measured via X‐ray computed tomography

“…Integrated crop–livestock systems can provide various benefits in terms of increased nutrient cycling (Franzluebbers, 2007), improved soil aggregation (de Moraes et al., 2014), ecosystem services, environmental sustainability, and farm profitability (Russelle, Entz, & Franzluebbers, 2007). However, the improvement in soil properties under ICLS depends particularly on adequate management of the livestock (Kumar et al., 2019) and the duration of crop–livestock integration (Singh, Abagandura, & Kumar, 2020). Properly managed grazing under ICLS can increase soil aggregate stability (Loss, Pereira, Giácomo, Perin, & dos Anjos, 2012), total porosity, soil macroporosity (Bonetti, Paulino, de Souza, Carneiro, & Caetano, 2018), and biodiversity (de Moraes et al., 2014).…”

Simulating Hydrological Responses of Integrated Crop‐Livestock Systems under Future Climate Changes in an Agricultural Watershed

“…We considered a conventional cropping system (corn [ Zea mays L.]‐ soybean [ Glycine max (L.) Merr. ]; two‐year rotation) integrated with light grazing of corn residues (one cow per hectare grazing corn residues for 55 days), with the assumption of no change in soil physical properties (Singh et al 2020). Additional information for the crop and grazing management operations are described in Table 1.…”

Integrating beef cattle on cropland affects net global warming potential

“…Prior investigations of ICL systems in the northern Great Plains of North America have evaluated management effects on grain and animal production (Kumar et al 2019;Karn et al 2005), soil and water attributes (Singh et al 2020;Faust et al 2018;Ryschawy et al 2017), and GHG flux dynamics (Abagandura et al 2019;Barsotti et al 2013). To date, no evaluation has been conducted in the region to quantify ICL system effects on net GWP.…”