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• Organic agriculture may support sustainable production goals. • LCA can be used to assess organic crop sustainability in diverse contexts. • Organic field crop LCA studies from 2010-2021 were reviewed. • Data were collected on crops, locations, LCI data, and soil and emissions models. • Recommendations were made for data to collect from organic farmers. The purpose of this manuscript is to review LCA studies of organic field crops to identify best practices in collecting life cycle inventory data. Previous LCA studies of organic field crops from 2010 to 2021 were identified and data were collected in the following categories: 1) crops studied, 2) geographical locations and spatial resolution, 3) life cycle inventory data collected, 4) models used for estimating changes in soil carbon and for estimating field-level emissions and their associated data inputs. Based on these data, recommendations were made with respect to the best data to collect, and emissions and soil carbon models to use for LCAs of organic field crops. Based on the assessment of LCI inventory data collected for activities, inputs and emissions modelling, a list of recommendations for future LCI data collection for organic field crops was tabulated. This included the data that should come directly from farmers, as well as data from secondary sources, and the specific models that can be used for soil carbon and emissions modelling. The recommendations made based on the LCI data identified can be used to inform data collection for high quality, regionally resolved LCAs of organic field crop production. [ABSTRACT FROM AUTHOR]

Policy initiatives have motivated a search for environmentally sustainable alternatives to fossil-fuel-based electricity generation. Agricultural residues such as corn cobs may be a suitable feedstock. A life cycle approach was used to estimate the greenhouse gas ( GHG) emission impacts associated with the use of pellets produced from corn cobs as the sole fuel for the generation of electricity at a hypothetically retrofitted coal-fired generating station in Ontario, Canada. Pellets are compared with current coal and hypothetical natural gas combined cycle ( NGCC) facilities. A life cycle model and soil carbon model calibrated for the agricultural region of interest were combined to quantify the GHG emissions of the biomass product system. The corn cob product system's life cycle emissions (240 g CO2eq kWh−1) are 40% and 80% lower than those of the NGCC and coal product systems, respectively. If corn cobs are left in the field to decompose, some carbon is sequestered in the soil, thus their removal from the field and combustion at the generation station represents a net GHG emission, accounting for 60% of life cycle emissions. In addition to the GHG impacts of combustion, removing agricultural residues from fields may reduce soil health, increase erosion and affect soil fertility through loss of soil organic carbon and nutrients. Their sustainable use should therefore consider the maintenance of soil fertility over the long-term. Nevertheless, the use of the feedstock in place of coal may provide substantial GHG emissions mitigation. [ABSTRACT FROM AUTHOR]

Replacement of fossil fuels with sustainably produced biomass crops for energy purposes has the potential to make progress in addressing climate change concerns, nonrenewable resource use, and energy security. The perennial grass Miscanthus is a dedicated energy crop candidate being field tested in Ontario, Canada, and elsewhere. Miscanthus could potentially be grown in areas of the province that differ substantially in terms of agricultural land class, environmental factors and current land use. These differences could significantly affect Miscanthus yields, input requirements, production practices, and the types of crops being displaced by Miscanthus establishment. This study assesses implications on life cycle greenhouse gas ( GHG) emissions of these differences through evaluating five Miscanthus production scenarios within the Ontario context. Emissions associated with electricity generation with Miscanthus pellets in a hypothetically retrofitted coal generating station are examined. Indirect land use change impacts are not quantified but are discussed. The net life cycle emissions for Miscanthus production varied greatly among scenarios (−90-170 kg CO2eq per oven dry tonne of Miscanthus bales at the farm gate). In some cases, the carbon stock dynamics of the agricultural system offset the combined emissions of all other life cycle stages (i.e., production, harvest, transport, and processing of biomass). Yield and soil C of the displaced agricultural systems are key parameters affecting emissions. The systems with the highest potential to provide reductions in GHG emissions are those with high yields, or systems established on land with low soil carbon. All scenarios have substantially lower life cycle emissions (−20-190 g CO2eq kWh−1) compared with coal-generated electricity (1130 g CO2eq kWh−1). Policy development should consider the implication of land class, environmental factors, and current land use on Miscanthus production. [ABSTRACT FROM AUTHOR]