New Zealand is home to a staggering 45 million sheep and 8 million cattle, which together produce 90 percent of the country’s methane emissions — or about 43 percent of the country’s greenhouse gas emissions. To meet the terms of the Kyoto Protocol on climate change, New Zealand has to reduce its greenhouse gas emissions to 1990 levels — but legislation proposed by the government last week would exempt the agricultural sector from any taxes levied to control the problem. The government has made clear, however, that the agricultural sector should focus on R&D to control methane emissions. New Zealand scientists say they know where to start: by altering the pastures in which sheep and cattle graze to include more of the legume lotus. According to the scientists, lotus contains tannin compounds that reduce methane emissions from ruminant animals by as much as 16 percent. The finding is a promising development in the effort to control agricultural contributions to global warming, which generally receive less attention than industrial pollution sources.
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