Simulating tree growth response to climate change in structurally diverse oak and beech forests

Area of Science:

• Forest Ecology
• Climate Change Science
• Computational Biology

Background:

• Forest ecosystems face significant threats from climate change, impacting productivity and resilience.
• Understanding species-specific responses to environmental shifts is crucial for effective forest management.
• Individual-based process models offer a powerful tool for simulating complex forest dynamics.

Purpose of the Study:

• To simulate oak and beech forest growth under various climate change scenarios.
• To evaluate the influence of site properties and stand characteristics on forest response.
• To assess the impact of rising carbon dioxide concentrations on forest productivity.

Main Methods:

• Utilized the HETEROFOR individual process-based model for forest growth simulation.
• Validated the model using data from 36 long-term forest monitoring plots.
• Conducted simulations under constant and variable carbon dioxide concentrations for future climate scenarios.

Main Results:

• Climate change induced moderate net primary production (NPP) gains in continental/mountainous zones but no change in oceanic zones under constant CO2.
• NPP was negatively affected by increased temperature and decreased rainfall, with some influence from soil water and stand characteristics.
• Rising CO2 concentrations significantly enhanced NPP for both oak and beech due to the fertilization effect.
• Stand characteristics explained substantial NPP variability (44% and 34%) under constant and variable CO2, respectively, more than climate change scenarios.

Conclusions:

• Forest stand characteristics play a critical role in determining forest productivity and response to climate change.
• Rising atmospheric CO2 concentrations offer a significant potential to increase forest productivity and resilience.
• Foresters can actively manage stand properties to enhance the adaptive capacity of broadleaved forests to climate change.