A significant portion of our greenhouse gas emissions is caused by the production of food. Emissions from food production are typically addressed from two different perspectives, the demand side (behavioral) and the supply side (management). Behavioral activities include promotion of locally-produced food, organic food, and eating less meat. The management side looks at efficiencies in production.
At a session on Wednesday afternoon, Eric Holst of the Environmental Defense Fund and Paul Buttner of the California Rice Commission presented their findings with on-the-ground efficiency experiments in California rice fields.
There are over a half million acres of rice in California. Rice cultivation is one of the more emissions-heavy crops because of the need for large amounts of water throughout the year. The rice industry also has a financial incentive to address greenhouse gas emissions. They’re hoping that more efficient farming methods will allow them to enter the carbon market by selling carbon offsets for the reduced emissions that result from greater efficiencies in the system. The researchers’ methods included mid-season crop drainage and alternative methods of rice straw disposal. The effects of mid-season crop drainage, an unnerving thought for many rice farmers, will be demonstrated by a pilot project currently underway.
Frank Mitloehner of UC Davis presented his upcoming article entitled “Clearing the Air: Livestock’s Contribution to Climate Change.” Mr. Mitloehner studied the discrepancy between United Nations, U.S. EPA, and California estimates of the percentage of greenhouse gas emissions attributed to livestock. The U.N. reports that livestock emissions are close to 18% of total emissions related to human activities on the planet, while the U.S. reports that these emissions are closer to 5% of the total in the United States. Mr. Mitloehner found that a large factor was the conversion of forest land that naturally sequesters carbon, to grazing land, which does not. Deforestation of this kind has halted (even recessed, according to some sources) in the United States, which is why our nationally reported livestock emissions are such a small portion of US emissions relative to global livestock emissions. Countries like Brazil and India, on the other hand, are converting forested land to grazing land at an alarming rate to make room for a booming cattle industry.
Regardless of whether our cattle raising and rice growing practices are more sustainable than other countries, lifecycle emissions for American food consumption are much higher than our foreign counterparts. Whether it’s the corn that feeds our cows or the vehicle and ship emissions it takes for Chinese rice to reach our supermarkets, the American food footprint is gigantic — roughly 15 pounds of CO2e per day per person. In that sense, although the supply side seems to be making a good effort, we still have a need to focus on the demand side of things to effectively control greenhouse gas emissions related to food production.
