Researchers have found that microbes living in an ice-covered lake in Antarctica feed on pebbles. And little creatures thrive.
Glacial lakes are bodies of fresh water, most of which are found in. being found South Poletrapped between EarthCrust or rock, thick layers of ice – sometimes several miles thick. These lakes are teeming with various microbes that feed on the nutrients in the water. However, researchers are not yet sure of the exact source of these nutrients.
Subglacial lakes naturally erode over time as water levels rise and fall. In a new study, researchers replicate this erosion in the lab by crushing sediment samples from Lake Whillans – a 60-square-kilometer subglacial lake buried under 800 meters of ice in Antarctica, she revealed. How the biochemicals needed to maintain microbial communities are made.
“Our study is very different from any previous study of subglacial lakes,” Beatrice Gill Olivas, a glaciologist at the University of Bristol in the UK, told Live Science. “Previous studies have investigated how erosion of shale rocks in subglacial environments can produce gases, but our study went further and examined how erosion can also release biologically important sources of nutrients into the water.”
She added that the discovery could have “exciting implications” for studying how microbial life evolved elsewhere in the universe.
Lake Whillans goes through periods of filling and drying. When it is full it is called a high amphitheater, and when the lake is drained it is called a low platform. The difference in depth between the high and low terraces of Lake Whillans is about 4 m: the high terraces reach 12 m in height and in the lower terraces they drop to 8 m. But at the lower terraces, the glacial stream — a fast-flowing passage inside the ice sheet — is in direct contact with large portions of the lake, Gil Olivas said. “So you can expect some erosion,” she added.
Gil Olivas said Lake Whillans is also part of a larger hydrological system and erosion that occurs in connected areas can add chemicals to the larger lake.
The researchers replicated this erosion in the lab by crushing sediment samples from Lake Whillans and leaving them in water without water at 32 degrees Fahrenheit (0 degrees Celsius). OxygenMimic conditions in the lake.
The researchers analyzed sediment samples from the Whillans Ice Stream Subglacial Access Research Drilling project. The scientists used a hot water drill to drill a well through the thick ice sheet before taking samples using a sterile bore.
release of chemicals
The researchers left the crushed rock underwater for more than 40 days and then analyzed the water to see which chemicals were released from the sediment. You can find a variety of different chemicals including hydrogenmethane carbon Dioxide and ammonium.
Most of these chemicals are immediately released from the sediment when crushed.
“When it is crushed, the sediment breaks down into much smaller particles,” Gil Olivas said. “This allows microscopic bubbles in the minerals, so-called fluid inclusions, to open up to release gases and liquids that were previously trapped in these bubbles.”
The gases trapped between the individual sediment grains are also released into the water, she added.
However, others have formed over time as some minerals dissolve or react with other molecules in the water.
A group of microbes known as methanotrophs feed on methane to produce the energy needed for growth. The opposite happens with methanogens, which generate energy by converting hydrogen and carbon dioxide into methane. There is also a lake specialist bacteria which obtain their energy by converting ammonium to nitrite and then to nitrate, a process known as nitrification.
Many of the compounds formed in subglacial lakes are also highly reducing or oxidizing, which means that they readily release and accept electrons during chemical reactions, also creating what is called a redox gradient in the lake. This color gradient helps recycle elements that can have multiple oxidation states, such as: matches or requirementsBy allowing them to easily gain and lose electrons. Specialized microbes, called chemolithotrophs, can catalyze the oxidation of these elements as an energy source.
Essentially, the researchers found a group of microbes that evolved to use them for energy, for every chemical in the lake.
These findings could be useful to researchers looking for extraterrestrial life. It is believed that subterranean lakes and frozen oceans are common in the universe, even in our region Solar System.
“The lakes in Antarctica could be a substitute for the harsh environments of other planetary systems,” Gil Olivas said. “It provides insights into how microbial life survives in other environments.”
Basically, when you have ice on top of sediments or rocks accompanied by liquid water, erosion can be a source of nutrients and energy for microbial life.
“Of course, we can’t say that these processes will definitely support exoplanet microbes,” Gil Olivas said. “However, there are certainly some ideas about how microbes survive on icy planets and moons.”
The study was published online in the journal on June 29 Terrestrial and Environmental Communication.
Originally published on Live Science.