Fossil-fuel carbon emission control in irrigated maize production

To evaluate optimal management strategies which reduce fossil-fuel carbon emissions, an idealized gross returns objective function was developed for the production of irrigated maize with the inclusion of a disincetive carbon-taxing term. The gross returns objective function is multivariant and optimized through a gradient search procedure. Carbon emissions emanating from maize production stem from the utilization of fossil-fuel energy on the farm as well as the utilized to manufacture many of the production inputs (i.e. fertilizers and pesticides). Particular emphasis was placed on determining fertilizer (nitrogen) and irrigation (furrow) management strategies which reduced fossil-fuel carbon emissions at a minimum reduction in gross returns. Total emissions and optimal maize yield were reduced slightly at high carbon-taxing rates, whereas gross returns decreased considerably. Decreases in optimal maize yield were a consequence of reducing applied water and nitrogen fertilizer, both of which are energy-intensive production inputs. The most effective means of reducing fossil-fuel carbon emissions associated with maize production at minimum reductions in gross returns is increasing the price of nitrogen fertilizer rather than levying a carbon tax.