SASL team member graduate student Milutin Djurickovic samples greenhouse gases in the long-term Farming Systems Project. (Photo credit Michel Cavigelli)

This post is part of the Science Tuesday feature series on the USDA blog. Check back each week as we showcase stories and news from USDA’s rich science and research portfolio.

Understanding the causes of greenhouse gas (GHG) emissions from agricultural landscapes is truly a multi-scale challenge, with GHG sources ranging from whole plant, to the microscopic microbe level.  For example, denitrification, the production of nitrous oxide, is the result of the action of just a few unique enzymes produced by a small number of bacteria and fungi in the soil.  These small players have huge importance because nitrous oxide is a greenhouse gas 300 times more powerful than carbon dioxide. Increases in nitrous oxide and other GHGs have been implicated in major global changes such as increased mean annual temperatures, resulting in melting glaciers, increasing floods, and more frequent heat waves. Read more »

Agriculture Secretary Tom Vilsack is speaking today at the United Nations Climate Change Conference in Cancun, Mexico, at 2:30 p.m. EST.  He will be addressing actions that USDA is taking to strengthen the role of agriculture and forestry in helping to address climate change. The Secretary will discuss ways landowners can reduce greenhouse gas emissions and increase carbon sequestration while improving their financial bottom line. The speech will be streamed live via web broadcast and the public is invited to watch his presentation at:    http://www.connectsolutions.com/cop16/index.html at 2:30 p.m. today. Read more »