Livestock greenhouse gasses could be cut, study says

Monday 27th Sep 2010 by theWeather Club

Greenhouse gas emissions caused by livestock farming in tropical countries could be cut significantly, according to a new study published in the Proceedings of the National Academy of Sciences. "Several technologically straightforward steps in livestock management could have a meaningful effect on greenhouse gas build-up.” said Philip Thornton of the International Livestock Research Institute (ILRI), who co-authored the paper with ILRI senior scientist Mario Herrer

Livestock farming contributes about 18% of the world's greenhouse gases, with many analysts worrying that this number is set to rise due to increasing demand for meat and milk in developing countries. Thornton and Herrero believe there are options readily available to prevent the up to 417 million tons of carbon dioxide expected to be produced by livestock in tropical countries in the next 20 years. According to the study, practices such as switching to more nutritious pasture grasses, supplementing diets with even small amounts of crop residues or grains, restoring degraded grazing lands, planting trees, and adopting more productive breeds,would have a significant effect.

For example, in Latin America, they noted that switching cows from natural grasslands to pastures sown with a more nutritious grass called Brachiaria can increase milk production and weight gain up to three fold, meaning fewer animals being necessary to meet demand. In addition the Brachiaria would absorb more carbon than degraded natural grasslands. "Even if only about 30 percent of farmers switch from natural grass to Brachiaria, that alone could reduce carbon dioxide emissions by about 30 million tons per year," Thornton said.

"We wanted to consider the impact in tropical countries because they are at the epicenter of a livestock revolution," said Herrero. "We expect consumption of milk and meat to roughly double in the developing world by 2050." Carols Seré, ILRI's Director General, said Thornton's and Herrero's work usefully steers the discussion of livestock's contribution to climate change away from constant criticism of the impact of farm animals and towards meaningful efforts to address the environmental consequences of their production.