Plants are losing genetic diversity and it's visible from space, study finds

Climate Change Alters Plant Genetics (Image: AI Generated)

In the silence of Greece’s highlands, a quiet struggle unfolds. The gentle slopes, once bursting with medicinal mountain herbs, are now losing their green soul. Scientists say time may be running out for plants like Sideritis, also known as Greek mountain tea.

Shrubs advance as open grasslands retreat

Mountain regions hold rich biodiversity but are now under pressure. Global warming and changing land use are transforming open grasslands fast. For fifty years, higher temperatures and fewer grazing activities have helped trees and shrubs take over. This process, called “mountain greening”, is pushing out low-growing native plants.

One such plant is Sideritis, used for teas and medicine. Found mainly in the Mediterranean mountains, it treats colds, coughs and stomach problems. Its presence signals the health of open mountain ecosystems. Now, it is under threat from habitat changes.

A closer look at genetic loss in Greek peaks

A team of researchers studied the plant’s genetic makeup in detail. They collected samples from eleven mountain ranges across Greece. By using satellite data and comparing herbarium specimens from the 1970s with present-day samples, they mapped genetic changes.

The findings were clear. In eight of eleven regions, Sideritis showed a sharp loss in genetic variety. In the worst-hit areas, up to 20% of plant DNA showed signs of inbreeding. Fewer plants and shrinking populations are the likely cause.

Professor David Nogués-Bravo from the University of Copenhagen said loss of genetic variety weakens the plant. It struggles more with disease, drought and sudden stress. Without diversity, it risks vanishing altogether.

Monitoring from space may hold the key

The study brings together space technology and plant science. By linking satellite images with gene data, researchers could track changes over decades. This approach could help monitor difficult-to-reach mountain areas from afar.

Professor Thomas Hickler from the Senckenberg Centre said vegetation density helps predict genetic erosion. This makes it easier to act before plants are beyond saving.

The team highlighted the importance of museum plant collections. Old herbarium records were vital to see long-term changes. Without them, comparisons over fifty years would not be possible.

Mountain greening is not just a local issue. It is happening globally as warmer climates and reduced farming reshape high-altitude lands. The study urges new research and conservation efforts in the worst-affected areas.

Spyros Theodoridis, lead author, said more species and regions need study. Only then can scientists understand how climate change affects the genes of biodiversity—and how to stop the damage.