Measuring Agricultural Sustainability: Energy Analysis of Conventional Till and No-Till Maize in the Georgia Piedmont

The ecological sustainability of human production systems has been a major topic of discussion and study since the late 1980s. In the realm of agriculture, scholars have had difficulty identifying a whole ecosystem measure of sustainability. This paper examines the feasibility of using energy input/output analysis as a measure of agricultural sustainability, and uses such analysis to compare the efficiency of conventional and no-till farming practices. The study presents results from an experiment conducted in the Georgia Piedmont to determine the energy output/input ratios for conventional and no-till maize plots under irrigated and nonirrigated conditions. The experiment provided mixed results on whether or not no-till agriculture is a more energy efficient or sustainable agricultural practice. The authors conclude that the question as to which system is more sustainable depends on what is being measured and over what time frame. Even within the context of a short-term experiment, no-till was more efficient, hence sustainable, if total above-ground biomass production was considered. This is a justifiable approach if benefits of carbon sequestration are considered. In contrast, conventional till was more efficient in the short-term if maize kernel production alone was considered (the most important aspect to individual farmers in economic terms). Energy input/output analysis is a potentially viable measure of agricultural sustainability that deserves further study.