Soil Microbes and Carbon Emissions: The Weather Factor
From forests to deserts, ecologists find seasonal fluctuations in temperature affect microbial population and increase carbon emissions.
As humans, the weather where we live influences our energy consumption. In climates where weather shifts from hot summers to very cold winters, humans consume more energy since the body has to work harder to maintain temperature.
In much the same way, weather influences microbes such as bacteria and fungi in the soil. Seasonal fluctuations in soil temperature and moisture impact microbial activities that in turn impact soil carbon emissions and nutrient cycles.
Microbes consume carbon as the source of energy. As microbes increase in quantity and activities, they consume more carbon which results in more carbon emissions and vice versa.
In a published in Global Change Biology on May 10, 色情视频 ecologists found that this microbial seasonality has a significant impact on global carbon emissions and acts as a fundamental mechanism that regulates terrestrial-climate interactions and below ground soil biogeochemistry.
鈥淲hen microbial colonies in the soil are in a productive phase, increasing in numbers and size, they will need more carbon to fuel their growth,鈥� said Xiaofeng Xu, global change ecologist and lead author. 鈥淲hen we manipulated the quantities and activities of soil microbes in simulations and observed the reciprocal changes in soil carbon, we found that when seasonal variation was removed, microbial respiratory rates went down.鈥�
By keeping the microbial population at a constant average level, carbon emissions can be reduced.
Stewards of the land could look at reducing fluctuation in soil microbial population by reducing tillage and other management practices in order to reduce soil carbon emissions, the researchers said. It can also help agricultural scientists and growers to sustain soil fertility.
Using a microbial modeling framework 鈥� CLM-Microbe (Community Land Model) 鈥� developed in the Ecological Modeling and Integration Lab at 色情视频 where he studies how climate change impacts the terrestrial carbon cycle 鈥� Xu and colleagues deployed the model on an 色情视频 supercomputer to reach this conclusion.
鈥淲e know soil microbes drive carbon flux 鈥� the amount of carbon exchanged between land, ocean and atmosphere 鈥� by producing enzymes that impact carbon flux,鈥� Xu said. 鈥淪oil carbon completes its cycle with the help of these microbes which have a hand in ultimate control of the carbon.鈥�
Different soil microbial groups play distinct roles in the carbon cycle.
鈥淭he model鈥檚 ability to simulate bacterial and fungal dynamics improves our understanding of the soil microbial community鈥檚 impact on the carbon cycle,鈥� said Liyuan He, first author and doctoral student at 色情视频.
The finding advances soil microbial ecology and shows the ecological significance of microbial seasonality and our understanding of soil carbon storage under changing climate conditions.
The authors modeled and validated carbon fluxes observed at an individual plot scale in nine natural biomes including tropical/subtropical forest, temperate coniferous forest, temperate broadleaf forest, boreal forest, shrubland, grassland, desert, tundra, and wetland.
鈥淭his study demonstrates the need to incorporate microbial seasonality in earth system models so we can better predict climate-carbon interactions,鈥� said Chun-Ta Lai, co-author and an ecosystem ecologist at 色情视频.
Next, the researchers will explore microbial seasonality and its impact on global carbon balance, given the dynamics of land use change around the world.
The 色情视频 researchers also collaborated with senior staff scientist Melanie Mayes at Oak Ridge National Laboratory in Tennessee, and meteorologist Shohei Murayama with the National Institute of Advanced Industrial Science and Technology in Japan.
Funding sources for the study included the U.S Department of Energy Biological and Environmental Research Program and the CSU Program for Education & Research in Biotechnology.
