Paradox! The methane cycle remains a mystery

Methane once enabled life, but it is now dangerous to us as a greenhouse gas. Researchers in Vienna are studying the effect of over-fertilization of lakes, rivers and seas on the methane cycle.

It was a prerequisite for the emergence of life on Earth, but today it plagues us as a climate-destroying greenhouse gas: methane. The chemical compound of carbon and hydrogen (CH₄) originated in the planet's early watery regions and then rose – a gas with a lower density than air – into the upper layers of the atmosphere. There, no less methane haze prevented the ground from freezing.

However, additional warming is the last thing the planet needs these days. In addition, atmospheric methane – which accumulates over twenty years – produces about 80 times more energy than carbon dioxide (CO).₂). As a dangerous greenhouse gas, most people are probably familiar with it in relation to cows, which emit methane primarily through belching. However, CH escapes₄ Not only from livestock stomachs, but also from landfills, rice fields, and production facilities in the natural gas, oil, and coal industries. As a general rule, the odorless and colorless gas is formed wherever microorganisms break down organic matter through metabolism in the absence of oxygen (anaerobic). That's why the idea of ​​thawing permafrost, where large amounts of methane are stored, as on the seafloor, can certainly bring lines of worry to the forehead.

Methane despite oxygen

Numerous natural sources of methane production, such as tropical wetlands, are increasingly becoming the focus of studies – also in order to be able to better classify the extent and consequences of human-induced climate change. At the University of Vienna, environmental microbiologist Barbara Bayer is currently taking a closer look at aquatic ecosystems. There is little reliable knowledge about microbial processes in water bodies and how changes in environmental factors affect the natural methane cycle. One thing is certain: while a number of microorganisms produce methane, others break it down again.