As soon as our planet warms, a world hidden from us permafrost is beginning to revive, and researchers are concerned that the microscopic organisms that inhabit the frozen soil will produce more greenhouse gases, accelerating global warming.
"No one has addressed the question of what might happen to the microbes when the permafrost begins to melt," - said Dzhensson Janet (Janet Jansson), a senior researcher at the National Laboratory them. Lawrence Berkeley, California. It has reviewed, watching what happened when the territories of Alaska permafrost melted for the first time in 1200.
"We now have a complete picture of what was happening in reality" - said Dzhensson, which, together with his colleagues managed to organize the genetic material of microbes residing both in frozen and thawing permafrost soils. During the observations, they also discovered a previously unknown microbe science and streamlined its entire genetic code, or genome.
Permafrost is soil that is in the frozen state for thousands or even hundreds of thousands of years, which includes dead plants or other organisms that existed during the formation of permafrost. Under the impact of increased global temperatures, the organic material begins to melt, allowing microbes to break down it. During this process, they produce greenhouse gases containing carbon. Scientists are particularly concerned about the fact that this process can promote the formation of large amounts of methane, carbon containing, which is entering the atmosphere accelerates global warming.
Scientists fear melting permafrost, because it contains a large amount of carbon that could exacerbate global warming. Thus, according to experts, the permafrost in polar regions contain 250 times more greenhouse gas emissions than was observed in the United States in 2009.
To find out how the microbes will respond to warming, the researchers used samples of permafrost and the upper layer of ice that melts in the summer and is considered the "active layer" in Alaska. The researchers then sequenced the DNA of microbes contained in the two samples taken from the permafrost, using the method known as metagenomics. Then they melted the samples at a temperature of 5 degrees Celsius and again examined the genetic content after first two days and then seven days later. The researchers also measured the concentration of the sample gas emissions.
Initially, two days after the microbes thawed, scientists have noted the allocation of a large concentration of methane. By the end of seven days, the concentration of methane is significantly diminished. The test samples also produces large amounts of carbon dioxide, the level of which is in contrast to the methane did not subside.
Using genetic confirmation, the researchers were able to observe how the populations of bacteria present in the samples changed over time. It is possible that the bacteria that absorb methane, will be able to offset some of the levels of methane in the atmosphere emitted by their brethren, if the permafrost melting will occur at a low rate, as noted Dzhensson. "It will completely depend on the scenario of the environment during the thaw." Indicators such as the rate of melting and the amount of organic material in the soil will affect this trend, she said.
Original: LiveScience Translation: M. Potter