Potential for research into biodiversity that has so far been overlooked: the worldwide measuring stations for monitoring air quality apparently also record genetic traces of the creatures in their region in addition to pollutants. In a pilot study, researchers were able to identify numerous animal and plant species by analyzing the environmental DNA trapped in the filter systems. According to the scientists, the already well-established monitoring network could be used to gain important information on the global biodiversity crisis.
What creatures are found in an ecosystem? For a long time, researchers were only able to pursue this question through complex inspections, observations and traditional forms of searching for clues. However, a new method has found its way into biodiversity research in recent years: traces of genetic material can be detected in environmental samples that can be assigned to specific original organisms. This so-called environmental DNA comes from tiny particles of skin or excreta that stick to objects or get into certain substances.
As has been shown, aquatic organisms can be detected particularly effectively using genetic traces, and examining various solids such as soil material can also be worthwhile. Last year, researchers were also able to show that environmental DNA is also in the air: using special devices that blew air through filters, they were able to identify many animal species in a zoo based on the floating genetic traces. The scientists, who included Elizabeth Clare from York University and Joanne Littlefair from Queen Mary University of London, attested that the method had considerable potential for biodiversity research. However, the process seemed to involve some technical effort.
Can air quality and biodiversity be recorded together?
However, it is now becoming apparent that an effective infrastructure for studying biodiversity using air-environmental DNA already exists in many parts of the world. The publications from 2022 led to the discovery. Through them, scientists at the British National Physical Laboratory (NPL) in Teddington, who operate the national air quality measuring networks, became aware of the possible additional potential of their stations. “We routinely collect air pollutants, so when we saw the study results we realized we might be sitting on more valuable data,” says NPL's James Allerton. So he and his colleagues contacted the environmental DNA researchers and a collaboration developed.
For the current study, the team led by Littlefair and Clare specifically explored the extent to which usable traces of genetic material from the air end up in the filters of the widespread air quality monitoring networks alongside fine dust and other atmospheric pollutants. The scientists carried out the corresponding investigations using the example of two measuring stations in England and Scotland. For this purpose, genetic material was extracted from the filters, duplicated and analyzed. The sequences could then be compared with information from genetic databases in order to be able to assign them to living beings.
Enormous potential revealed
As the team reports, the pilot study revealed that more than 180 representatives of plants, fungi, insects, mammals, birds, amphibians and other groups of living beings could be detected using the environmental DNA from the filters. These included rare or endangered species that occur in the vicinity of the two test stations. "We were surprised by the diversity of life that we were able to capture with a single approach," says senior author Clare. It is becoming apparent that air quality monitoring networks have been recording local biodiversity data unnoticed for many years, the researchers conclude. An interesting aspect is that samples are often kept for decades, so that retrospective studies on the development of biodiversity may now also be possible.
"The potential cannot be overestimated," says lead author Littlefair. “It could be a game changer in biodiversity mapping and monitoring. Almost every country in the world has a system or network for measuring air quality - either government or private, and in many cases both. This could solve the global problem of how to record biodiversity on a large scale with little effort,” says the scientist. She and her colleagues now want to campaign for the international implementation of this approach: "While efforts are also required to collect and analyze these samples, it is an extraordinary opportunity to use an already existing, global information source," says Littlefair .
Source: Specialist article: Current Biology, doi: 10.1016/j.cub.2023.04.036