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Updated: Aug 1, 2026
10:05
Integrated Field Lysimetry and Porewater Sampling for Evaluation of Chemical Mobility in Soils and Established Vegetation
Published on: July 4, 2014
A source-sink framework for coupling water, carbon, and nutrient dynamics of vegetation
1Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
Tree Physiology
|July 1, 1991
Summary
Photosynthesis and plant growth are closely linked, with growth being more sensitive to environmental stress. Internal feedback mechanisms, particularly sink regulation, commonly influence photosynthesis in soil-plant systems.
Area of Science:
- Plant Physiology
- Ecology
- Biophysics
Background:
- Photosynthesis and plant growth are interconnected processes.
- Environmental factors like water and nutrients significantly impact plant physiology.
- Understanding these feedbacks is crucial for plant science and ecosystem modeling.
Purpose of the Study:
- To review the feedbacks between photosynthesis and growth.
- To analyze the influence of environmental factors on these relationships.
- To outline a framework for modeling carbon dynamics in soil-plant systems.
Main Methods:
- Literature review of photosynthesis-growth relationships.
- Analysis of environmental stress impacts (water, nutrients).
- Development of a source-sink framework for carbon dynamics modeling.
Main Results:
- Photosynthesis strongly depends on photosynthate utilization.
- Plant growth is more sensitive to water and nutrient stress than photosynthesis.
- Internal feedback effects, driven by growth responses to external factors, often confound observed photosynthesis-external variable relationships.
Conclusions:
- Sink feedback regulation of photosynthesis is a common occurrence in soil-plant systems.
- The proposed source-sink framework can model carbon dynamics with coupled water and nutrient interactions.
- This understanding is vital for predicting plant responses to environmental changes.
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