Related Experiment Video
Updated: Jul 29, 2026
09:36
The Use of High-resolution Infrared Thermography (HRIT) for the Study of Ice Nucleation and Ice Propagation in Plants
Published on: May 8, 2015
Ecophysiological analysis of two arctic sedges under reduced root temperatures
Gregory Starr1, Dawn S. Neuman, Steven F. Oberbauer
1Department of Biological Sciences, Florida International University, Miami, FL 33199, USA.
Physiologia Plantarum
|March 23, 2004
Summary
Low soil temperatures significantly reduce photosynthesis in arctic sedges like Eriophorum vaginatum and Carex bigellowii. This impacts ecosystem carbon exchange due to their prevalence in tundra environments.
Area of Science:
- Plant physiology
- Arctic ecology
- Environmental science
Background:
- Arctic vascular plants experience a significant temperature differential between shoots and roots.
- Root temperatures in tundra environments often remain near freezing, even during the growing season.
Purpose of the Study:
- To investigate the impact of reduced soil temperatures on photosynthetic parameters and abscisic acid (ABA) concentrations in two key tundra sedges: Eriophorum vaginatum and Carex bigellowii.
- To determine the role of soil temperature as a primary driver of photosynthesis in arctic sedges.
Main Methods:
- Subjecting E. vaginatum and C. bigellowii to controlled, reduced soil temperatures.
- Measuring key photosynthetic parameters: light-saturated photosynthesis (Amax), variable to maximal fluorescence (Fv/Fm), and stomatal conductance.
- Quantifying root and leaf abscisic acid (ABA) concentrations.
Main Results:
- Both stomatal conductance and Amax significantly decreased in both sedge species as soil temperatures declined.
- The variable to maximal fluorescence (Fv/Fm) ratio was less affected by decreasing soil temperatures.
- Abscisic acid (ABA) concentrations in both roots and leaves increased with decreasing root temperatures.
Conclusions:
- Soil temperature is a critical factor influencing photosynthetic activity in arctic sedges, affecting key physiological processes.
- The observed responses suggest that soil temperature directly impacts carbon assimilation in these dominant tundra species.
- Given their abundance, the sensitivity of E. vaginatum and C. bigellowii to soil temperature has significant implications for arctic ecosystem carbon exchange.
Related Concept Videos
01:57Adaptations that Reduce Water Loss
Though evaporation from plant leaves drives transpiration, it also results in loss of water. Because water is critical for photosynthetic reactions and other cellular processes, evolutionary pressures on plants in different environments have driven the acquisition of adaptations that reduce water loss.
02:45Responses to Heat and Cold Stress
Every organism has an optimum temperature range within which healthy growth and physiological functioning can occur. At the ends of this range, there will be a minimum and maximum temperature that interrupt biological processes.