Biodiversity Holds the Key to Dryland Survival Under Grazing Pressure

A major global study led by researchers at King Abdullah University of Science and Technology (KAUST) has revealed that plant diversity plays a decisive role in helping dryland ecosystems withstand grazing pressure.

The research, published in Nature Ecology & Evolution, analysed 73 dryland sites across 25 countries, spanning grasslands, shrublands, savannas and steppes. Using standardised field data, scientists compared ecosystems exposed to varying levels of grazing intensity.

The findings show that increased grazing typically reduces vegetation cover—by an average of 35 percent. However, the extent of damage varies significantly depending on biodiversity levels.

Plant species richness emerged as the most important factor determining resilience. Ecosystems with a greater variety of plant species were far better at maintaining vegetation cover, even under sustained grazing pressure.

Researchers explain that diverse plant communities distribute stress more effectively. Different species adopt varied survival strategies—such as tolerance, rapid recovery or resistance—which collectively buffer the ecosystem. In contrast, less diverse systems lack this flexibility and degrade faster.

The study also challenges conventional assumptions about vegetation types. Shrub-dominated landscapes were not necessarily more resilient—especially when they reduced overall plant diversity.

With drylands supporting nearly half of global livestock production and over a billion people, the findings carry major implications. Experts say sustainable grazing policies must go beyond controlling livestock numbers and focus on conserving and restoring plant diversity to ensure long-term ecosystem stability.