For a layman, the term ‘Fungi’ could create visuals of the common yeasts, moulds or the more familiar mushrooms. It is almost unfathomable how these tiny organisms have been doing us a great favour when it comes to fighting against climate change and protecting our planet. It is in common knowledge that forests help in the mitigation of global warming by absorbing carbon dioxide from the atmosphere and storing it in soil and its biomass. Fungi, however, play an invisible but critical role in controlling climate change as well. The anthropogenic activities such as combustion of fossil fuels emit greenhouse gases like carbon dioxide and nitrous oxide gases. Nitrogen pollution as a result of nitrous oxide has been on the rise in many countries and this has put some fungi at risk which may accelerate the process of climate change.
Fungi such as mycorrhizal fungi exist under the ground and live symbiotically with the roots of the trees. Not only these mycorrhizal fungi help roots to receive more water and nutrients, but they also help the trees absorb more carbon dioxide from the atmosphere. The ectomycorrhizal fungi, in particular, could further increase this absorption and trees can absorb carbon at a much faster rate. Not all forests have mycorrhizal fungi, so their absorption rate is much lower than that of the forests which have mycorrhizal fungi in the roots of their trees. Further, the ectomycorrhizal fungi reduce the rate of decomposition which means carbon from forests returns to the atmosphere slowly. These fungi, with their carbon absorption feature, make some forests better at capturing the carbon dioxide and thus helping us naturally against global warming.
Nitrogen pollution has been threatening these ‘climate warriors’. Burning of fossil fuels emits nitrous oxide gas which can have detrimental effects on these forests and ectomycorrhizal fungi which are quite sensitive to nitrogen pollution. The forests which have been exposed to more nitrogen pollution have been found with lesser mycorrhizal fungi. Fewer mycorrhizal fungi mean lesser carbon dioxide absorption which in turn would mean more concentration of CO2 in the atmosphere. As CO2 has a heat-trapping attribute, it triggers more global warming and climate change. A loss of mycorrhizal fungi could have serious implications for forests across the world and our planet which has already been facing terrifying challenges of climate change.
The good news is in a country like the US which is one of the biggest emitters of greenhouse gases, nitrogen pollution is on the decline. However, in developing nations with more economic growth, nitrogen pollution has increased by leaps and bound which has been negatively impacting the forests with mycorrhizal fungi. These mycorrhizal fungi, if restored in the affected forests, can help us further attenuate the repercussions of climate change. We have technology which can filter out nitrous oxide from the source of emissions and prevent it from releasing into the atmosphere. Implementation of these technologies can help curb the nitrogen pollution and thus can conserve these fungi which can help us in our fight against climate change!