Least‐Cost Input Mixtures of Water and Nitrogen for Photosynthesis

In microeconomics, a standard framework is used for determining the optimal input mix for a two‐input production process. Here we adapt this framework for understanding the way plants use water and nitrogen (N) in photosynthesis. The least‐cost input mixture for generating a given output depends on...

Full description

Saved in:
Bibliographic Details
Published in:The American naturalist 2003-01, Vol.161 (1), p.98-111
Main Authors: Wright, Ian J., Reich, Peter B., Westoby, Mark
Format: Article
Language:English
Subjects:
Australia
Biology
Carbon dioxide
Carbon Dioxide - metabolism
Darkness
Energy Metabolism
Environment
Humidity
Hyperbolas
Leaf area
Models, Biological
Nitrogen
Nitrogen - metabolism
Photosynthesis
Plant Transpiration
Plants - metabolism
Rain
Stomatal conductance
Transpiration
Trees
United States
Water
Water - metabolism
Water consumption
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In microeconomics, a standard framework is used for determining the optimal input mix for a two‐input production process. Here we adapt this framework for understanding the way plants use water and nitrogen (N) in photosynthesis. The least‐cost input mixture for generating a given output depends on the relative cost of procuring and using nitrogen versus water. This way of considering the issue integrates concepts such as water‐use efficiency and photosynthetic nitrogen‐use efficiency into the more inclusive objective of optimizing the input mix for a given situation. We explore the implications of deploying alternative combinations of leaf nitrogen concentration and stomatal conductance to water, focusing on comparing hypothetical species occurring in low‐ versus high‐humidity habitats. We then present data from sites in both the United States and Australia and show that low‐rainfall species operate with substantially higher leaf N concentration per unit leaf area. The extra protein reflected in higher leaf N concentration is associated with a greater drawdown of internal CO2, such that low‐rainfall species achieve higher photosynthetic rates at a given stomatal conductance. This restraint of transpirational water use apparently counterbalances the multiple costs of deploying high‐nitrogen leaves.
ISSN:0003-0147
1537-5323
DOI:10.1086/344920