It is well established that aerosols are relevant for the climate, for example, because they contribute to cloud formation. However, natural, biological aerosols emitted by plants serve another important purpose. They help disperse living microorganisms across the globe, affecting their distribution. Yet little is known about those bioaerosols emitted by pristine forests such as the Amazon. And even less about the diversity of the microorganisms in the aerosols.
Felipe Souza and co-authors now collected bioaerosols at our ATTO site. Then they extracted and analyzed the DNA to determine the communities present. This is the first study which described the community of microorganisms within aerosols in the Amazon. They found many different types of bacteria and fungi. Some were cosmopolitan taxa, but they also identified many that are specific to certain environments such as soil or water. This suggests that the atmosphere may act as an important gateway for bacteria to be exchanged between plants, soil, and water.
Their results also reveal that the main source for bioaerosols emitted from the Amazon rainforest are organisms that are known to disperse their spores through the atmosphere: fungi and bacteria. We know that these groups of organisms can produce enzymes and metabolites including antibiotics. Finding them in the vast jungle wilderness of the Amazon, however, is difficult. Analyzing forest aerosols may be a way to localize them for the potential use in biotechnological applications.
Souza et al. published this paper as a Short Communication in Science of the Total Environment.
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