It's long been known methane occurs in landfills, but until now scientists weren't sure of the mechanism behind the buildup, a release from North Carolina State University said Wednesday.
University researchers say they've found that one particular microbe -- Methanosarcina barkeri -- kicks off the process and paves the way for other methane producers.
"Landfills receive a wide variety of solid waste, and that waste generally starts out with a fairly low pH level," Francis de los Reyes, an associate professor of civil engineering, said. "The low pH level makes it difficult for most methanogens -- methane-producing organisms -- to survive."
What the researchers found was M. barkeri, a hearty methanogen that can survive at low pH levels while consuming the acids in its environment, producing methane and increasing the pH levels. This, in turn, makes the environment more amenable for other methanogens.
Methane is a powerful greenhouse gas. While a problem for the environment, methane also can be useful since it can be, and often is, collected at landfill sites and used for power generation.
"The research community can use our findings to explore ways of accelerating the methane-generation process," de los Reyes said, "creating methane more quickly for power generation, and making additional room in the landfill for waste disposal."