Scientists learn to see the hidden world beneath our feet - from the sky
A new study by Dr Angela Harris from The University of Manchester and Professor Richard Bardgett from Lancaster University has revealed that scientists can now detect the hidden world of microbes living in the soil - from the air.
Published in , the research shows that detailed airborne images capturing many parts of the electromagnetic spectrum can be used to predict the abundance and diversity of microbes that live in the soil beneath plant canopies. This offers a new way to monitor soil health and biodiversity.
Soil is the most biodiverse and complex habitat on Earth, and the microbes that live in it - tiny bacteria and fungi that recycle nutrients, store carbon, and keep ecosystems healthy - are fundamental to a healthy planet. Yet, because they live underground, they are notoriously difficult and expensive to measure across large areas.
Recent research shows that the types of plants growing in an area and their traits - such as how fast they grow or what their leaves are made of - can strongly influence soil microbes. What was not known until now was whether these relationships hold up to predict the abundance and diversity of microbes across different ecosystems.
In this study, researchers used airborne sensors that record light far beyond what the human eye can see. Because these sensors capture hundreds of narrow wavelength bands, they reveal fine details about plant leaves and canopies, such as their chemistry, structure, and overall health.
By combining this rich spectral information with field measurements of soil microbes and plant traits collected across the continental United States through the National Ecological Observatory Network (NEON), the team found strong links between plant canopy reflectance and the types and diversity of microbes living in soil.
鈥淭he chemistry and structure of plant leaves, which determine how they reflect light, are tightly linked to the conditions of the soil they grow in,鈥� said Dr Harris. 鈥淏ecause plants and microbes often respond to the same environmental factors - like soil nutrients or climate - we can use what鈥檚 happening above ground to predict what is happening below.鈥�
Importantly, the study showed that full-spectrum hyperspectral data - which captures far more detail than traditional satellite imagery - performed far better than simpler vegetation indices such as NDVI. This suggests that upcoming hyperspectral satellites, including the European Space Agency鈥檚 CHIME and NASA鈥檚 Surface Biology and Geology (SBG) missions, could transform how we monitor soil health on a global scale.
Our findings show that the detailed spectral information captured from airborne sensors can tell us a lot about the microbes living in the soil. With advanced hyperspectral satellites planned for launch soon, this approach could make monitoring soil health and biodiversity at continental and even global scales possible and affordable.
Beyond advancing ecological science, the research could provide vital tools for tracking soil carbon storage, monitoring land degradation, and supporting sustainable land management in the face of climate change.
鈥淭his research opens up a powerful new window into Earth鈥檚 hidden biodiversity, providing a way to map and monitor soil biodiversity at large scales in a cost-effective way,鈥� said Professor Bardgett.