A study published in the latest issue of the journal Nature Climate Change, conducted by University of New Hampshire professor Serita Frey together with a team from the University of California-Davis and the Marine Biological Laboratory, concluded that increase in temperatures will lead to additional release of carbon from soils.
The authors explain how soil microorganisms respond to warmer climate, causing changes in the normal carbon dioxide flux from soils. In the past, the flux has been strictly controlled by plants uptake of carbon from the atmosphere through the process of photosynthesis.
However, due to human induced climate change this balance is very likely to get disturbed. As Frey states, soil microorganisms play a very significant role in controlling carbon concentrations in the atmosphere.
The study presents two scenarios, short and long term, based on variation in food sources available to these microorganisms and temperature. In a short term, the ability of soil to use glucose from plant roots will not be severely affected. However, the efficiency to use more complex food sources such as phenol with increase in temperatures, is predicted to drop by 60 percent.
Frey explains that this is due to the higher amounts of released carbon dioxide and these results apply only to the complex food sources, which might be interpreted as worsening of the climate problem.
Surprisingly, the effect decreases in the long term scenario, covering the next 18 years, indicating that the original predictions might be exaggerated.
In addition, the team looked at the long term impact that changes in soil microorganism’ efficiency might have on carbon storage. The main motivation behind this is that current models always assume that efficiency is fixed and it is not influenced by changes in temperatures. The results from the study revealed that variations in this flux are crucial for better prediction of future climate change. The authors strongly recommend that new models should be developed taking the fluctuation of this parameter into account.
The team hypothesize that microorganisms might become more efficient with changes in temperature in a long run. This is mainly because of the ability of the soil microorganisms to adapt to the new conditions.