Needle age and season influence photosynthetic temperature response and total annual carbon uptake in mature Picea mariana trees.

ABSTRACT:

Background and aims

The carbon (C) balance of boreal terrestrial ecosystems is sensitive to increasing temperature, but the direction and thresholds of responses are uncertain. Annual C uptake in Picea and other evergreen boreal conifers is dependent on seasonal- and cohort-specific photosynthetic and respiratory temperature response functions, so this study examined the physiological significance of maintaining multiple foliar cohorts for Picea mariana trees within an ombrotrophic bog ecosystem in Minnesota, USA.

Methods

Measurements were taken on multiple cohorts of needles for photosynthetic capacity, foliar respiration (Rd) and leaf biochemistry and morphology of mature trees from April to October over 4 years. The results were applied to a simple model of canopy photosy

SUBMITTER: Jensen AM 

PROVIDER: S-EPMC4590327 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature