A CU-Boulder team working at 16,400 feet in the Peruvian Andes has discovered how barren soils uncovered by retreating glacier ice can swiftly establish a thriving community of microbes, setting the table for lichens, mosses and alpine plants. The team was led by Steve Schmidt (EBIO) and included INSTAARs Sasha Reed and Diana Nemergut; additional co-authors included Cory Cleveland, (former INSTAAR, now at U Montana) as well as others from CU-Boulder and Univ. of Toledo. The researchers extracted DNA from the soil to pinpoint new groups of microbes and polymerase chain reaction, or PCR, to amplify and identify them. They found that three types of a photosynthetic microbe known as cyanobacteria colonized the soil within the first year, either by dropping in from tiny pockets of dirt wedged in the receding glacier or blowing in as spores. Just three years later the diversity increased greatly; there were 20 different species of bacteria, growing by snatching gaseous forms of carbon and nitrogen from the atmosphere. The team also unexpectedly found that the microbes were stabilizing the soil by weaving soil particles together with their filaments as well as excreting a glue-like sugar compound.
Their study provides new insights into how microorganisms are adapting to global warming in cold ecosystems on Earth and has implications for how life may have once flourished on Mars. The research also could lead to the discovery of new antibiotics, as well as industrial enzymes that function at cold temperatures and could be used to drive chemical reactions normally requiring large amounts of heat. The team's paper was published online Aug. 26 in the Proceedings of the Royal Society B, the flagship biological research journal for the United Kingdom's national academy of science.