Inconsistency between process-based model and dose-response function in estimating biomass losses in Northern...

Area of Science:

• Environmental Science
• Forest Ecology
• Atmospheric Chemistry

Background:

• Tropospheric ozone (O3) concentrations have risen significantly in the Northern Hemisphere due to anthropogenic emissions and climate change.
• Elevated O3 poses a threat to forest health, carbon uptake, and overall ecosystem function.

Purpose of the Study:

• To compare methodologies for estimating ozone-induced biomass potential losses (BPL) in Northern Hemisphere forests.
• To assess the impact of O3 on different forest types using concentration-based (AOT40) and flux-based (POD1) metrics.
• To compare dose-response functions with the process-based ORCHIDEE model for BPL estimation.

Main Methods:

• Comparison of AOT40 and POD1 metrics for estimating O3-induced BPL.
• Utilized dose-response functions and the ORCHIDEE process-based model.
• Regression analysis between BPL and Gross Primary Production (GPP) anomalies.

Main Results:

• Deciduous forests, especially boreal and continental types, showed higher sensitivity to O3-induced biomass loss than evergreen forests.
• Europe and North America exhibited greater BPL compared to Asia and North Africa.
• Continental deciduous forests displayed stronger correlations between O3 exposure and productivity.

Conclusions:

• Flux-based metrics (POD1) are more reliable for assessing O3 impacts on forests than concentration-based metrics.
• Current dose-response functions may need further validation across diverse forest ecosystems.
• Findings underscore the need for effective forest management and conservation strategies considering O3 risks.