Temperature rising would slow down tropical forest dynamic in the Guiana Shield

Area of Science:

• Ecology
• Climate Science
• Forestry

Background:

• Tropical forest functioning is closely linked to climate variability.
• Key drivers include annual precipitation, temperature, and seasonal water stress.
• Predicting tropical tree community responses to climate change is complex due to interacting demographic processes.

Purpose of the Study:

• To simulate the response of a tropical forest community in the Guiana Shield to projected climate change over the next century.
• To assess the impact of different climate scenarios (RCP2.6, intermediate, RCP8.5) on forest ecosystem dynamics.
• To identify key climate drivers influencing tropical forest structure and function.

Main Methods:

• Utilized a joint individual-based model for tropical forest simulation.
• The model incorporates climate-dependent growth and mortality rates.
• Simulations were run for 100 years using IPCC 5AR climate predictions under various scenarios and a control.

Main Results:

• All simulated ecosystem process and structure variables (basal area, biomass, diameter, growth, mortality) decreased compared to the control.
• Sensitivity analysis revealed temperature as the strongest climate driver.
• A potential temperature-driven drop of 40% in average forest growth was identified.

Conclusions:

• Tropical forests in the Guiana Shield face a significant risk of growth slowdown under projected climate change.
• Rising temperatures are identified as the most critical factor impacting forest dynamics.
• The findings underscore the vulnerability of tropical ecosystems to global warming.