Study illustrates role of microbes in climate change

Bret Belden

By Madeline Ragland, Contributing Writer

In a recent study in Sweden, scientists conducted research on the microbes that live in the permafrost soil. This research discovered the different types of microbes that are releasing methane into the atmosphere, contributing to climate change.

One of the scientists who participated in this study was the University of New Hampshire’s very own Dr. Carmody McCalley.

Microbes, or microorganisms, are single-celled organisms that live in the environment, particularly soil.

“Microbes breathe out methane, like humans breathe out carbon dioxide,” McCalley explained. Because there are billions and billions of microorganisms in the environment, the release of this methane begins to add up, creating a prominent effect on the environment. Methane is a strong greenhouse gas that is believed to contribute to climate change.

The microbes specifically studied in Sweden lived in the many levels of the permafrost soil. As the earth becomes warmer, more permafrost is thawing. The collapse of the ground due to the thawing permafrost changes the environment from dry to wet. Different microbes exist at different parts of the soil and different oxygen levels, so there is a change in the microbial makeup as the soil changes from dry to wet, due to lack of oxygen.

“This study in Sweden in particular studied ‘who’ the microbes are in the soil,” McCalley explained. Going into the study, these scientists already knew that microbes release methane, so this study was specifically designed to determine the DNA sequence of the microbes in order to better understand what kinds live in the soil.

The scientists collected the soil and some of McCalley’s colleagues sequenced the DNA in order to determine what kind of microbe existed at that particular part of the soil.

“The group of microbes changed due to the permafrost thawing,” McCalley stated. “There are different sources of food for microbes which determine what kind of species they are. The type of microbe [present] affected the way that they made methane.”

“Methane has different fingerprints,” McCalley explained, “and as the permafrost thaws, the fingerprints change due to the change in the microbes.” The climate models will change to account for the changing fingerprints of the microbes resulting from the altered environment. The wrong number of microbes would make the amount of methane produced by these microbes inaccurate, which would affect the amount of methane that is released into the atmosphere.

If the permafrost continues to thaw, there will be more places for the microbes to make methane, due to the increased wetness of the soil. The more it thaws, the more greenhouse gases will be released which changes the climate.

McCalley specifically studies “how climate change happens.” She is focused on understanding how methane is produced from these microbes, and she works with other scientists in order to better grasp how climate change is occurring due to the release of different greenhouse gases.

In order to better understand how to solve this problem of climate change, scientists study the types of microbes that release methane into the atmosphere. They measure how much methane is in the environment and, based on where the methane comes from, they can determine the best way to limit the release of these greenhouse gases.

McCalley’s work focuses on understanding the effects of the environment in the hopes that this better understanding will lend to possible solutions for this problem. “Global warming is an issue for all global citizens; and I say this as a member of society, not as a scientist,” McCalley said. “It is an important issue for all humans, regardless of where you live.”

Her studies don’t highlight solutions to global warming, but they provide information about what is affecting climate change due to the greenhouse gases that are being released by these microorganisms. In order to make good policy changes to limit global warming, research — similar to the study in Sweden — needs to be conducted.

McCalley believes that “understanding how global warming works is important for UNH students and other members of society, because it allows people to understand why global warming is an important issue and why we should be concerned.”