![Photo of Boise State Evolution and Behavior Ph.D. student Sandra Velazco](https://www.boisestate.edu/coas/wp-content/uploads/sites/225/2024/08/Sandra-Velazco-300x300.jpg)
Sandra Velazco, an Ecology, Evolution and Behavior Ph.D. student at Boise State, was lead author on an article studying how climate change impacts cloud mountain forests. Another Ecology, Evolution and Behavior Ph.D. student, Andri Zaiats, and College of Arts and Sciences faculty members Jodi Brandt and Trevor Caughlin are among Velazco’s international team of coauthors. The article, titled “Hotter, drier climate influences tropical tree cover loss and promotes bracken fern dominance within arrested successional patches in Andean Cloud Forests,” was published in Biological Conservation in August 2024.
Velazco, who came to Boise State from Peru in 2019, and her coauthors studied the Andean Cloud Forests in the north of her home country. These forests, alongside the world’s other tropical forests, account for 22% of global carbon sequestration. They’re also teaming with a wide variety of life. Their loss would severely damage regional biodiversity and the Earth’s ability to store carbon dioxide in vegetation.
Over recent decades, the invasive bracken fern plan has taken over swaths of previously forested land throughout the Andes. Velazco and her coauthors analyzed historical satellite images, comparing them to annual climate data to explore the relationship between climate and tree cover in the forests.
The group found that tree cover fell off more significantly in drier years. They also noticed greater rates of decline at forest edge zones and higher elevations. They predict that tree cover in tropical forests will continues to decline as climate changes drives global average temperatures up.