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- Natural disturbances are major drivers of tropical forest dynamics, yet their role in Central Africa’s old-growth rainforests, the world’s second largest tropical forest block, remains poorly quantified. Here we present the first regional assessment of windthrow, the uprooting or breakage of trees by wind. Using Landsat imagery from 2019 to 2020, we detected 74 windthrow events ≥30 ha, collectively affecting ~18,600 ha. These events were concentrated in eastern regions where mesoscale convective systems and extreme rainfall are most frequent. Sizes of windthrow events followed a Weibull...AuthorsRobinson Negron-Juarez, Yanlei Feng, Douglas Sheil, Michael Keller, Elsa M. Ordway, Daniel Magnabosco Marra, Jose D. Urquiza-MuñozSourcenpj Natural HazardsYear2026
Water availability modulates maximum canopy heights of low-elevation Amazonian second-growth forests
Tropical second-growth forests of the Amazon sequester large amounts of carbon and are important carbon sinks, contributing substantially to climate change mitigation, biodiversity conservation, and providing crucial ecosystem services. Deforestation due to selective logging and shifting cultivation is expanding second-growth forest areas in tropical forest regions, which if well managed, regenerate rapidly over time. Maximum forest canopy height is an important metric of biomass and carbon accumulation in second-growth forests and is strongly influenced by water availability. The water...AuthorsMidhun Mohan, Gilberto Z. Pastorello, Yanlei Feng, Esmaeel Adrah, Michael Keller, Ewane Basil Ewane, Marcos Longo, Ovidiu Csillik, Antonio Ferraz, Abhilash Dutta Roy, Lin Meng, Jeffrey Q. ChambersKeywordsSourceTropical EcologyYear2026- Water resource managers need Streamflow Duration Assessment Methods (SDAMs) to predict if streams are ephemeral, intermittent or perennial. Although SDAMs exist for some regions of the United States, no validated SDAM has been developed for Puerto Rico and the US Virgin Islands. This review lays the foundation for a US Caribbean SDAM that will be accurate and practical by characterizing trends in stream research and identifying flow class documentation, candidate indicators of streamflow duration and a hydrogeographic framework. We screened 2081 titles and abstracts and 750 full-text...AuthorsKatiana Garcia-Rosado, Ken M. Fritz, Augustin C. Engman, Tamara Heartsill Scalley, Sean P. Kelly, Carlos E. Ramos-Scharrón, Sofía Olivero-LoraKeywordsSourceAquatic Conservation: Marine and Freshwater EcosystemsYear2026
- Brazil contains 15–20% of the world’s biodiversity, with forests originally covering 88% of its territory, now reduced to about 58%. The country has committed to restoring at least 12 million ha of forests by 2030. Seeding is a cost-effective method for tropical forest restoration, widely used in Brazil, but its effectiveness for species-rich forests is still uncertain due to low establishment rates for many species. Most seeding research has involved relatively few species, and many are short-lived, raising concerns about long-term ecosystem development. Invasive grasses and loss of...AuthorsVera Lex Engel, Diego Carveira de Souza, John A. ParrottaKeywordsSourceREFORESTAYear2026
- This study assessed heat vulnerability in the city of Ponce, Puerto Rico, by integrating satellitederived land surface temperature (LST) data with demographic and socioeconomic indicators. Spatial analysis, principal component analysis (PCA), and multivariate regression were applied to develop a Heat Vulnerability Index (HVI) that maps heat risk across urban neighborhoods. Environmental variables, LST, Normalized Difference Vegetation Index (NDVI), impervious surface cover, slope, and elevation, were analyzed alongside indicators such as age, disability, living alone, poverty, and unemploym...AuthorsLaura T. Cabrera-Rivera, Frank E. Muller-Karger, Digna Rueda-Roa, Heriberto Marin, Tischa A. A. Munoz, Pablo A. Mendez-LazaroKeywordsSourceUrban ClimateYear2026
- Little is known about the structure of tropical forests despite its critical role in the provisioning of ecosystem services. Here we assess the vertical structure of forests in the Brazilian Amazon with a large-scale airborne LiDAR dataset. We show that fire has greater impact in the lowest forest strata, differently from selective logging and windthrow. We also find that secondary forests quickly recover or even exceed reference areas at the 1-10m height stratum but that full recovery for the 20-30m height stratum has not been achieved even after 35 years. Our modeling results suggest...AuthorsDenis Valle, Leo Haneda, Ismael Verrastro Brack, Jean Ometto, Ovidiu Csillik, Marcos Longo, Michael Keller, Danilo AlmeidaKeywordsSourceCommunications Earth & EnvironmentYear2025
- Carbon–climate (CC) feedbacks — arising from response of land and ocean carbon sinks to elevated CO2 and climate warming — are critical yet highly uncertain drivers of Earth’s climate trajectory. Processes such as permafrost thaw, tropical forest dieback, reduced ocean uptake, and intensifying climate extremes are already weakening natural carbon sinks, with potential to amplify warming and accelerate crossing of tipping points. Detecting and quantifying these dynamics requires sustained, high-resolution, spatially-comprehensive Earth Observations. Drawing on outcomes from a 2024 community...AuthorsDustin Caroll,, Nicholas C Parazoo,, Nicole S. Lovenduski, Michael Keller, David S. Schimel, A. Anthony BloomSourceEnvironmental Research LettersYear2025
- Tree canopy height is a key indicator of forest biomass, productivity and structure, yet measuring it accurately at regional or larger scales, whether from the ground or remotely, remains challenging. The objective of this study is to generate the first complete canopy height map of the Amazon forest at 4.78m resolution using Planet NICFI imagery and deep learning. Specifically, we (i) trained a U-Net regression model with canopy height models (CHMs) derived from tropical airborne LiDAR and their corresponding Planet NICFI images to estimate canopy height, (ii) evaluated the accuracy of...AuthorsFabien H. Wagner, Ricardo Dalagnol, Griffin Carter, Mayumi C. M. Hirye, Shivraj Gill, Le Bienfaiteur Sagang Takougoum, Samuel Favrichon, Michael Keller, Jean P. H. B. Ometto, Lorena Alves, Cynthia Creze, Stephanie P. George-Chacon, Shuang Li, Zhihua Liu, Adugna Mullissa, Yan Yang, Erone G. Santos, Sarah R. Worden, Martin Brandt, Philippe Ciais, Stephen C. Hagen, Sassan SaatchiSourceRemote Sensing in Ecology and ConservationYear2025
- It is unclear how plants respond to increasing temperatures. Leaf heat tolerance (LHT) is often at its upper limit in tropical forests, suggesting that climate change might negatively impact these forests. We hypothesized that intraspecific variation in LHT might be associated with changes in the soil microbiome, which might also respond to climate. We hypothesized that warming would increase LHT through changes in the soil microbiome: we combined an in situ tropical warming experiment with a shade house experiment in Puerto Rico. The shade house experiment consisted of growing seedlings...AuthorsGabriela Hernandes Villani, Iana F. Grullón-Penkova, Parker Bartz, Joel Masanga, Jesse R. Lasky, Molly A. Cavaleri, Tana E. Wood, Benedicte BachelotKeywordsSourceEcology and EvolutionYear2025
- Hurricanes strongly regulate vegetation structure and dynamics in coastal tropical forests by causing tree mortality and damaging the crowns of surviving trees. Despite the importance of this damage for long-term forest demography and carbon dynamics, the patterns and drivers of variation in hurricane-induced damage across heterogeneous landscapes remain poorly quantified. Here, we integrate field inventory data with repeated airborne LiDAR measurements to quantify tree crown damage following Hurricane María (Category 4) in the Luquillo Experimental Forest, Puerto Rico. We applied two...AuthorsTao Han, António Ferraz, Dingyi Fang, Tian Zhang, Roi Ankori-Karlinsky, Gabriel Arellano, Douglas Morton, Jess K. Zimmerman, Michael Keller, María Uriarte, Xiangtao XuKeywordsSourceGlobal Change BiologyYear2025