Greenhouse gas assessment of soybean production: implications of land use change and different cultivation systems

Abstract

Highlights:• LC GHG balance of soybean is dominated by LUC emissions.• Significant GHG variation was calculated for LUC scenarios and cultivation systems.• Tillage systems have higher GHG emissions than reduced-(no-)tillage systems.• Uncertainty in N 2 O is high and dominates cultivation GHG emissions M A N U S C R I P T A C C E P T E D AbstractThe increase in soybean production as a source of protein and oil is being stimulated by the growing demand for livestock feed, food and numerous other applications. A C C E P T E D ACCEPTED MANUSCRIPTchoice is a critical issue in ensuring the lowest soybean GHG balance and degraded grassland should preferably be used for soybean cultivation. The highest GHG emissions were calculated for tropical moist regions when rainforest is converted into soybean plantations (tillage system). When land use change is not considered, the GHG intensity varies from 0.3 to 0.6 kg CO 2 eq kg -1 soybean. It was calculated that all tillage systems have higher GHG emissions than the corresponding no-tillage and reduced tillage systems. The results also show that N 2 O emissions play a major role in the GHG emissions from cultivation, although N 2 O emission calculations are very sensitive to the parameters and emission factors adopted.

100% Organic Poultry Feed: Can Algae Replace Soybean Expeller in Organic Broiler Diets?

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The challenging paradigm of interrelated energy systems towards a more sustainable future

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An international comparison of agricultural nitrous oxide emissions

“…There are several studies that have examined how carbon footprints can be reduced from cropping systems, such as: (1) including legume crops in the farming system to reduce both N 2 O and soil carbon emissions (Paul et al, 2002;Barton et al, 2014); (2) diversification of crop rotation to reduce overall carbon footprints (Yang et al, 2014); (3) keeping crop residue and application of manure on farms to increase soil carbon levels (Peterson et al, 2013;Knudsen et al, 2014;Mukul et al, 2016); (4) application of biochar into soil to reduce nutrient leaching and N 2 O emissions (Pudasaini et al, 2012); and (4) maintaining soil moisture levels below certain percentage to reduce the amount of direct and indirect N 2 O emissions (Castanheira and Freire, 2013). However, these are outside the scope of this paper and their impacts are, therefore, not considered.…”