Modelling carbon sources and sinks in terrestrial vegetation

Area of Science:

• Environmental science
• Ecology
• Climate change research

Background:

• Atmospheric CO2 is projected to increase, significantly impacting terrestrial ecosystems.
• Discrepancies exist between global studies showing CO2 fertilization effects and plant-scale evidence of less pronounced impacts.
• Accurate modeling of vegetation carbon sinks is crucial for predicting future climate change.

Purpose of the Study:

• To review current descriptions of plant carbon sources and sinks in terrestrial biosphere models.
• To highlight the uneven complexity in modeling photosynthesis versus other plant processes.
• To discuss pathways for improving mechanistic representations of plant carbon sinks.

Main Methods:

• Review of existing terrestrial biosphere models.
• Analysis of inconsistencies between global and plant-scale CO2 fertilization studies.
• Leveraging plant-scale models and observational data for model development.

Main Results:

• Terrestrial biosphere models show uneven complexity in representing plant carbon processes.
• Photosynthesis is often modeled with greater complexity than respiration, carbon allocation, and direct carbon sinks.
• A general lack of data on carbon sink dynamics hinders model improvements.

Conclusions:

• Current terrestrial biosphere models do not fully capture the complexity of plant carbon dynamics.
• Further research and data collection on plant carbon sink dynamics are needed.
• Improving model mechanistic representation is key to accurately predicting the terrestrial carbon sink response to rising CO2.