A team of microbiologists makes a global appeal about the need to take the microbial universe into account when we talk about a climate emergency. Why is it so important?
Although we don't see them, microorganisms are everywhere and are part of fundamental processes for the functioning of the world as we know it. In fact, it was primitive bacteria that first started releasing oxygen and changed the composition of the atmosphere in which we breathe today.
Our body is full of microorganisms; our microbiome has many essential functions in the body – from digestion, to supporting the immune system and preventing infections. Microorganisms greatly influence the health of humans and other living beings, impact agriculture, world food supply and various industries. They are able to colonize environments not reached by any other form of life and, in short, they are everywhere.
A study published in the journal PNAS in 2016 estimated that there are one million different species of microbes on Earth, and that 99.999% of this biodiversity is unknown to us.
It seems obvious, therefore, that all climate changes that occur on a global scale will affect the microbial community. It is also clear that, when making predictions about the consequences, it is necessary to take microbes into account. However, these are the great outsiders in the study of climate change. Scientists discuss the effect climate change has on flora and fauna, but they do not include microorganisms in this equation.
That is why a team of more than 30 microbiologists from nine different countries has called on the international scientific community to stop ignoring these life forms in climate change studies.
The decisions regarding climate change taken in the present affect humans and other forms of life, so if scientists won't take into account the microbial world, they are losing a very important component of the equation.
With this statement, the researchers aim to draw attention to the importance of microbes: how they can influence climate change and how they will be affected by it. They call for the need to include microorganisms in this research, to increase the development of innovative technologies and to raise awareness in the classroom on this subject.
According to Rick Cavicchioli, a researcher at UNSW Sydney University and leader of this global appeal, micro-organisms, including bacteria and viruses, are life forms not seen on conservation websites. This is odd, considering they are the support system of other higher life forms and their importance is critical to the regulation of climate change.
Some examples of the relevance of microorganisms to climate change research
It is estimated that 90% of the biomass in the oceans is microbial. Phytoplankton takes energy from the sun and traps carbon dioxide from the atmosphere, as well as being the basis of the food chain and the sustenance of the rest of life forms.
Another example given by scientists refers to the microscopic algae that live beneath the Antarctic ice sheets, the base of many food chains. As the ice melts, many of these life forms disappear, and with them goes an important food source for other species.
Same is true for terrestrial ecosystems. In terrestrial environments, microbes release a number of important greenhouse gases into the atmosphere (carbon dioxide, methane and nitrous oxide), and climate change is causing these emissions to increase.
In addition, climate change is also encouraging the spread of pathogenic microbes that cause disease in humans, animals and plants. Climate change expands the number and geographical range of disease vectors, such as mosquitoes, that contain pathogens. The end result is increased spread of disease and serious threats to global food supplies.
Microorganisms must play a greater role in climate change research
In their statement, scientists call on researchers, institutions and governments to commit to greater microbial recognition to mitigate climate change. According to the authors of the article, there is a great need to study microbial responses to climate change and to include microbial-based research in policy making and management decisions.
In addition, climate change research linking biological processes with global geophysical and climate processes should take more account of the microbial variable. According to the researchers, this variable significantly affects, and is affected by climate change, so if microorganisms are not considered, it means that models cannot be properly generated and predictions could be inaccurate.
More on the subject of climate change and microorganisms
Kirchman, D. L., Morán, X. A. & Ducklow, H. Microbial growth in the polar oceans — role of temperature and potential impact of climate change. Nat. Rev. Microbiol. 7, 451–459 (2009).
Danovaro, R. et al. Marine viruses and global climate change. FEMS Microbiol. Rev. 35, 993–1034 (2011).
Mackelprang, R., Saleska, S. R., Jacobsen, C. S., Jansson, J. K. & Tas, N. Permafrost meta-omics and climate change. Annu. Rev. Earth Planet. Sci. 44, 439–462 (2016).
Greaver, T. L. et al. Key ecological responses to nitrogen are altered by climate change. Nat. Clim. Change 6, 836–843 (2016).
Pecl, G. T. et al. Biodiversity redistribution under climate change: Impacts on ecosystems and human well-being. Science 355, (2017).
Cavicchioli, R. A vision for a ‘microbcentric’ future. Microb. Biotechnol. 12, 26–29 (2019).
Archer, S. D. J. et al. Airborne microbial transport limitation to isolated Antarctic soil habitats. Nat. Microbiol. 4, 925–932 (2019).