CIHEAM - Options Mediterraneennes

In this analysis energy inputs to crop production, emphasizing corn or maize, is compared for a series of agricultural systems of increasing complexity. Solar energy captured in corn yield is 2 to 8 times higher under intensive modern management systems than in hand or animal powered systems. The ratio of energy output to energy input is 2.14 to 1 for a modern tractor system and decreases to 0.73 to 1 when hoe agriculture is practiced. The reason for the change in the ratio is mainly due to a decrease in labor energy costs in modern systems, although fossil fuel costs do increase. Organic systems may or may not be more efficient than modern nonorganic systems depending upon the crops resistence to pests. Quality ,of the resources is also of great importance. Soil erosion and water are major problems which act to reduce yield and increase energy costs.