Where does the carbon go? A model-data intercomparison of vegetation carbon allocation and turnover processes at two temperate forest free-air CO2 enrichment sites.

De Kauwe, Martin G

Medlyn, Belinda E

Zaehle, Sönke

Walker, Anthony P

Dietze, Michael C

Wang, Ying-Ping

Luo, Yiqi

Jain, Atul K

El-Masri, Bassil

Hickler, Thomas

Wårlind, David

Weng, Ensheng

Parton, William J

Thornton, Peter E

Wang, Shusen

Prentice, I Colin

Asao, Shinichi

Smith, Benjamin

McCarthy, Heather R

Iversen, Colleen M

Hanson, Paul J

Warren, Jeffrey M

Oren, Ram

Norby, Richard J

2023-06-02T05:52:31Z

2023-06-02T05:52:31Z

2014-08

2023-06-02T05:52:27Z

Elevated atmospheric CO2 concentration (eCO2) has the potential to increase vegetation carbon storage if increased net primary production causes increased long-lived biomass. Model predictions of eCO2 effects on vegetation carbon storage depend on how allocation and turnover processes are represented. We used data from two temperate forest free-air CO2 enrichment (FACE) experiments to evaluate representations of allocation and turnover in 11 ecosystem models. Observed eCO2 effects on allocation were dynamic. Allocation schemes based on functional relationships among biomass fractions that vary with resource availability were best able to capture the general features of the observations. Allocation schemes based on constant fractions or resource limitations performed less well, with some models having unintended outcomes. Few models represent turnover processes mechanistically and there was wide variation in predictions of tissue lifespan. Consequently, models did not perform well at predicting eCO2 effects on vegetation carbon storage. Our recommendations to reduce uncertainty include: use of allocation schemes constrained by biomass fractions; careful testing of allocation schemes; and synthesis of allocation and turnover data in terms of model parameters. Data from intensively studied ecosystem manipulation experiments are invaluable for constraining models and we recommend that such experiments should attempt to fully quantify carbon, water and nutrient budgets.

1469-8137

1469-8137

https://hdl.handle.net/10161/27529

eng

Wiley

The New phytologist

10.1111/nph.12847

Trees

Carbon Dioxide

Carbon

Ecosystem

Biomass

Air

Models, Theoretical

Wood

Computer Simulation

Forests

Where does the carbon go? A model-data intercomparison of vegetation carbon allocation and turnover processes at two temperate forest free-air CO2 enrichment sites.

Journal article

Oren, Ram|0000-0002-5654-1733

883

899

3

Duke

Nicholas School of the Environment

Environmental Sciences and Policy

Earth and Climate Sciences

Published

203