Multiscale predictors of small tree survival across a heterogeneous tropical landscape

作者：Eileen H. Helmer, Shannon L. Kay, Humfredo Marcano‐Vega, Jennifer S. Powers, Tana E. Wood, Xiaolin Zhu, David Gwenzi, Thomas S. Ruzycki · 发表于：PLoS ONE · 年份：2023 · DOI：10.1371/journal.pone.0280322 · 被引用次数：8 · 研究领域：Forest ecology and management、Ecology and Vegetation Dynamics Studies、Plant Water Relations and Carbon Dynamics

Uncertainties about controls on tree mortality make forest responses to land-use and climate change difficult to predict. We tracked biomass of tree functional groups in tropical forest inventories across Puerto Rico and the U.S. Virgin Islands, and with random forests we ranked 86 potential predictors of small tree survival (young or mature stems 2.5-12.6 cm diameter at breast height). Forests span dry to cloud forests, range in age, geology and past land use and experienced severe drought and storms. When excluding species as a predictor, top predictors are tree crown ratio and height, two to three species traits and stand to regional factors reflecting local disturbance and the system state (widespread recovery, drought, hurricanes). Native species, and species with denser wood, taller maximum height, or medium typical height survive longer, but short trees and species survive hurricanes better. Trees survive longer in older stands and with less disturbed canopies, harsher geoclimates (dry, edaphically dry, e.g., serpentine substrates, and highest-elevation cloud forest), or in intervals removed from hurricanes. Satellite image phenology and bands, even from past decades, are top predictors, being sensitive to vegetation type and disturbance. Covariation between stand-level species traits and geoclimate, disturbance and neighboring species types may explain why most neighbor variables, including introduced vs. native species, had low or no importance, despite univariate co...