Temperature adjustments in sugar maple - acclimation and adaptation of photosynthesis and respiration

Journal Article · Thu Jun 01 04:00:00 EDT 1995 · Bulletin of the Ecological Society of America

OSTI ID:95796

Gunderson, C A; Norby, R J; Wiggins, L ^[1]

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1. Oak Ridge National Lab., TN (United States)

The assumptions underlying predictions of forest redistribution with climate change generally do not include the potential for adaptation or acclimation. Populations from the southern extreme of a species` range may have higher temperature optima, or individuals may be able to physiologically acclimate to temperature increases. Sugar maple (Acer saccharum) seedlings from a southern and a central geographic source were grown at either 27{degrees}/14{degrees} or 31{degrees}/18{degrees}C (day/night). Photosynthesis and respiration were measured across a range of cuvette temperatures to assess physiological acclimation and pre-existing genetic adaptation. The temperature response curves of photosynthesis had no sharp optima, but rates declined above 31{degrees}C. Curves did not differ with geographic source. Photosynthetic rates were somewhat higher in trees acclimated to the higher temperature, which could help compensate for reductions in assimilation at superoptimal temperatures. Respiration increased with increasing cuvette temperatures, and relationships were similar in trees from both sources. The temperature response for respiration shifted downward in seedlings grown at 31{degrees}, such that respiratory carbon losses at elevated growing temperatures were less than that predicted by relationships from ambient grown plants. These results suggest that for these sugar maple populations acclimation was more important than geographic source in determining the temperature responses of carbon dynamics.

• OSTI ID: 95796
• Report Number(s): CONF-9507129--
• Journal Information: Bulletin of the Ecological Society of America, Journal Name: Bulletin of the Ecological Society of America Journal Issue: 2 Vol. 76; ISSN BECLAG; ISSN 0012-9623
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
55 BIOLOGY AND MEDICINE
BASIC STUDIES
56 BIOLOGY AND MEDICINE
APPLIED STUDIES
BIOLOGICAL ADAPTATION
BIOLOGICAL EFFECTS
CLIMATIC CHANGE
MAPLES
PHOTOSYNTHESIS
RESPIRATION
SEEDLINGS
TEMPERATURE DEPENDENCE