Reducing greenhouse gas emissions in agriculture: challenges and possibilities

Global agriculture is affected by climate change that could significantly impact productivity. Large-scale afforestation and biomass for energy production as well as population and income growth, will exacerbate the competition for land. Agriculture is an important contributor to climate change, accounting directly for 10%–12% of anthropogenic greenhouse gas (GHG) emissions and also for around 70% of land use change emissions, mainly through deforestation. Soil acts as source and sinks for greenhouse gases (GHG) such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). Microbial activity, root respiration, chemical decay processes, as well as heterotrophic respiration of soil fauna and fungi produce GHGs in soils. Related emission flux rates largely depend on soil water content (humidity), soil temperature, nutrient availability, and pH value, plus land-cover-related parameters. Thus, meteorological and climatological parameters, as well as land-use management information, are paramount. Drivers can be separated into proximal drivers that influence soil emissions in the direct environment and distal drivers that effect soil emissions on larger scales. Considering the present study, we include the use of the following models: a) spatially explicit model of land-use choices to determine the possible effects of future changes in the drivers of land-use choices; and b) crop model - model that estimates spatially explicit profiles of GHG emissions from cropland with varying crop genetic productivity shifters, management systems, and climate scenarios