20th-Century hurricanes leave long-lasting legacies on tropical forest height and the abundance of a dominant wind-resistant palm

BACKGROUND:

Tropical cyclones are the major natural disturbance in many coastal forests. Their intensity is projected to increase due to global warming. The shifts in the frequency and intensity of tropical cyclones have detrimental implications on the long-term resilience of tropical forests in the North Atlantic basin. Cyclones affect some tree species more than others, leading to the recruitment of fast-growing pioneer species that are less resistant to wind. Frequent cyclones may interrupt succession and prevent pioneer species from establishing, resulting in shorter forests with less biomass. Nonetheless, there is a knowledge gap in understanding the impacts of cyclones on tropical forests and forest characteristics.

GOALS AND METHODS:

According to prior studies, Sierra palm (Prestoea acuminata var. montana) is extremely resistant to cyclones. The study seeks to examine the long-term selective effects of storms on this species at a large scale. The authors employ a novel machine learning framework and high-resolution aerial photos collected in 2017 over EL Yunque National Forest in Puerto Rice to map the distribution of the palm. The study area mainly comprises tropical evergreen forests, with Sierra palms dominating at high elevations.

CONCLUSION AND TAKEAWAYS:

The EL Yunque National Forest has shorter forest canopies due to historical exposure to hurricanes. Results from the study conclude that hurricanes alter forest canopy height. Also, hurricanes have selective effects on species composition over a long period. The study emphasizes that hurricane disturbance is responsible for wind-resistant species in Puerto Rico.