City life: airborne DNA metagenomic biodiversity monitoring reveals dynamic changes across time and space

A pioneering study has revealed the potential of airborne DNA metagenomics to monitor biodiversity across the tree of life in real-time. By collecting air samples and employing nanopore sequencing, researchers were able to conduct a comprehensive analysis of species present within just a few hours. Over the course of 77 samples collected from 13 different sites in London, including a yearly sampling campaign at the Natural History Museum Wildlife Garden, the team identified a staggering 1,916 species, ranging from bacteria and fungi to plants and animals.

The researchers noted that the distribution of these species varied spatially and seasonally, with communities shifting from plants dominating in the spring to ascomycete fungi becoming prevalent in the summer, and basidiomycete fungi taking over in late autumn and winter. Moreover, the abundance of plant species in the air samples increased in areas with nearby vegetation, indicating a connection between airborne signals and the surrounding habitat.

However, detecting catalogued garden plants proved to be challenging, as it depended on factors such as the availability of reference data, dispersal biology, plant size, and proximity to the collector. Despite these limitations, the study successfully demonstrated the feasibility of airborne shotgun metagenomics as a powerful tool for rapid, repeated, and scalable biodiversity assessment across both space and time.