| Summary: | Popular science: A Day in the Life of a Methane Bog Methane gas is continuously released from wetlands around the world. In Kobbefjord, Greenland the release of methane is low during the cold of winter and higher in warm summer months. But the amount released also varies from day to night; a pattern that has to do with both temperature and light. Methane is a waste product from bacteria living in the soil below the groundwater table. The bacteria producing methane are only able to live where no oxygen is present. Their production of methane is affected by plants growing at the ground surface above them, as the plants release sugars and oxygen into the soil through their roots. The bacteria consume sugars from the plants which helps them to decompose organic matter in the soil. On the other hand, oxygen released into the soil by plants causes methane production to drop, as no methane is produced where oxygen is present. How much methane is released from the wetland into the atmosphere depends partly on the amount produced, but also on how it is transported to the surface. In the same way that plants are able to transport oxygen from the air into the soil, methane in the soil can pass to the atmosphere through the roots, stems and leaves of plants. This is a relatively fast mode of transport. Alternatively, methane can move up slowly through the soil, but near the ground surface there are bacteria which consume methane as it rises up from below; therefore part of it never makes it to the surface. Both the bacteria that produce and those that consume methane are more active at warm than at cold temperatures. The same is true for plants, but these are also more active in light than in darkness. As a result, the plants release more sugars into the soil and usually transport more oxygen and methane during the day when it is light and warm. The methane producing bacteria often live at a depth in the soil where there is only little temperature difference between day and night. But the methane consuming bacteria near the ...
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