Diverse forests can better withstand extreme weather events, study finds. Here’s why

Forests around the globe are facing increasing challenges due to climate change. To better understand how they will cope, new research suggests focusing on the variety of tree species within the forest. Published in July in Nature Communications, the study examined thousands of acres of U.S. woodlands and discovered that the greater the diversity of tree species in a forest, the more resilient it becomes to the combined climate extremes caused by global warming.

These extremes include scenarios where extreme heat coincides with drought or unusually high rainfall.

Researchers had previously established that diversity across tree species generally enhances the overall strength of forests. However, most of this previous research involved smaller scales or experimental plots that had been planted by humans. The confirmation of this positive effect on expansive, complex systems of natural forests came as a surprise to the study's lead author, Xuetao Qiao, a postdoctoral researcher in ecology at Peking University in China.

Qiao expressed his and his team's uncertainty before completing the analyses, stating, "Before completing the analyses, we were genuinely uncertain whether we would be able to detect this relationship in real forests."

Furthermore, most research on forests' ability to withstand climate change has concentrated on their response to individual events, such as heatwaves. The findings of this study, however, indicate that a diverse mix of tree species can significantly improve a forest's capacity to withstand the compounded challenges posed by rising global temperatures.