Hotter Temperatures Reduce the Diversity and Alter the Composition of Woody Plants in an Amazonian Forest.

Rapid warming and high temperatures are an immediate threat to global ecosystems, but the threat may be especially pronounced in the tropics. Although low-latitude tree species are widely predicted to be vulnerable to warming, information about how tropical tree diversity and community composition respond to elevated temperatures remains sparse. Here, we study long-term responses of tree diversity and composition to increased soil and air temperatures at the Boiling River-an exceptional and unique "natural warming experiment" in the central Peruvian Amazon.

Leaf thermal safety margins decline at hotter temperatures in a natural warming 'experiment' in the Amazon.

The threat of rising global temperatures may be especially pronounced for low-latitude, lowland plant species that have evolved under stable climatic conditions. However, little is known about how these species may acclimate to elevated temperatures. Here, we leveraged a strong, steep thermal gradient along a natural geothermal river to assess the ability of woody plants in the Amazon to acclimate to elevated air temperatures.