Jun 14, 2010
Mechanical Sugarcane Harvesting Reduces Greenhouse Gas Emissions
Author: Michael Cordonnier/Soybean & Corn Advisor, Inc.
Mechanical sugarcane harvesting in Brazil is rapidly replacing the prior practice of harvesting the sugarcane by hand. Not only is mechanical harvesting more efficient, it also reduces greenhouse gas emissions, it improves the fertility of the soil, it improves the quality of the ground water, and it helps to sequester larger amounts of carbon compared to harvesting the sugarcane by hand.
One of the big problems of harvesting the sugarcane by hand is the fact that the dried leaves must be eliminated before the workers can cut the cane. The elimination of the leaves is accomplished by burning them off. Just prior to hand-harvesting a field, the leaves are burnt off in a flash-fire that consumes the field in a matter of minutes. This sugarcane burning results in increased releases of greenhouse gasses and increases in localized pollution. Especially harmful is the soot that causes respiratory problems and other adverse health effects. Most of the sugarcane is harvested during the dry season when there are very few rain showers to wash out the pollution from the atmosphere. The pollution from sugarcane burning can linger for months over a region.
The burning also eliminates organic matter that could help improve the soil. Mechanical harvesting leaves the organic matter in place which improves the fertility of the soil and helps to hold down on soil erosion as well. The increased organic content of the soil also helps to sequester carbon in the soil as well.
According to recent studies released in Brazil, mechanical sugarcane harvesting releases only 25% as much of greenhouse gasses as compared to harvesting by hand. Life cycle studies of ethanol in Brazil indicate that ethanol reduces greenhouse gas emissions by 60% to 90% compared to gasoline.
In the state of Sao Paulo, mechanical harvesting will be phased out as soon as sugarcane producers can purchase mechanical harvesters. There are only two manufactures of mechanical harvesters and the waiting time for delivery of a new harvester is months long.
While mechanical harvesting may have many positive environmental affects, it has a negative impact on the local labor market. By switching to mechanical harvesting, many thousands of local labors lose their jobs increasing rural unemployment.