Related Experiment Video
Updated: Jan 16, 2026
04:35
Development of an Individual-Tree Basal Area Increment Model using a Linear Mixed-Effects Approach
Published on: July 3, 2020
3.7K
Increasing tree size across Amazonia
Adriane Esquivel-Muelbert1,2,3,4, Rebecca Banbury Morgan5,6, Roel Brienen7
1School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, UK. a.esquivelmuelbert@bham.ac.uk.
Nature Plants
|September 25, 2025
Summary
Forests are growing larger as increased resources like carbon dioxide boost tree growth. Despite climate change, Amazonian trees are getting bigger, indicating resource availability is currently outweighing negative climate impacts.
Area of Science:
- Forest Ecology
- Climate Change Science
- Tropical Biology
Background:
- Global forest functioning is impacted by climate change and increased resource availability (e.g., CO2, nitrogen).
- Effects on forest structure, particularly tree size dynamics, remain unclear.
- Potential impacts vary: larger trees may benefit from resources, while smaller trees might adapt to changing light conditions, and larger trees could suffer from heat/drought.
Purpose of the Study:
- To assess recent changes in forest structure in the Amazon.
- To analyze the impact of increased resources and climate change on tree size over time.
Main Methods:
- Analysis of 30 years of tree records from 188 mature Amazonian forest plots.
- Statistical evaluation of changes in mean tree basal area and size distribution.
Main Results:
- Mean tree basal area in Amazonian forests increased by 3.3% per decade.
- Both the number and size of large trees increased.
- Small and large trees showed similar relative size gains, suggesting reduced suppression for smaller trees.
Conclusions:
- Increased resource availability (CO2 fertilization, nitrogen deposition) is currently mitigating negative climate change impacts on Amazonian forests.
- Forests are becoming larger, with trees growing more in size and number.
- The positive effects of resources on tree growth appear to outweigh negative climate impacts in this region so far.
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