Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2022 May 10;10(1):coac026. doi: 10.1093/conphys/coac026

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© The Author(s) 2022. Published by Oxford University Press and the Society for Experimental Biology.

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.

PMC Copyright notice

The surplus sharing fluxes and form a closed cycle in the root–shoot model. Blocked connector endings indicate a negative effect. Boxes indicate direct algebraic equations; green circles indicate fast state variables that buffer inputs and outputs. Both fluxes have a (negative) effect on the other flux. The more nitrogen the root shares, the more the shoot can grow, which in turn shares less carbon because its surplus is smaller. In the same way, a bigger surplus of carbon results in a smaller surplus of nitrogen. Top row: all interactions are direct, the model is not uniquely defined. All other rows introduce state variables that define the model uniquely. Middle row: state variables for and . Bottom row: state variables for only (left) and for only (right).

Inline graphic — The surplus sharing fluxes and form a closed cycle in the root–shoot model. Blocked connector endings indicate a negative effect. Boxes indicate direct algebraic equations; green circles indicate fast state variables that buffer inputs and outputs. Both fluxes have a (negative) effect on the other flux. The more nitrogen the root shares, the more the shoot can grow, which in turn shares less carbon because its surplus is smaller. In the same way, a bigger surplus of carbon results in a smaller surplus of nitrogen. Top row: all interactions are direct, the model is not uniquely defined. All other rows introduce state variables that define the model uniquely. Middle row: state variables for and . Bottom row: state variables for only (left) and for only (right).