Patterns of carbon storage in relation to shade tolerance in southern South American species

Published Date

Received for publication 23 May 2015.

Accepted for publication 7 August 2015.

Author
Frida I. Piper2

+Author Affiliations

1. Centro de Investigación en Ecosistemas de la Patagonia (CIEP), Simpson 471, Coyhaique, Chile; Universidad Austral de Chile, campus Patagonia, km 4 camino Coyhaique Alto, Coyhaique, Chile; and Instituto de Ecología y Biodiversidad (IEB), Santiago, Chile

1. ↵2Author for correspondence: fpiper@ciep.cl

Abstract

PREMISE OF THE STUDY: Carbon (C) allocation to storage in woody tissues at the expense of growth is thought to promote shade tolerance, yet few studies on the subject examined C storage during maximum growth and considered stand influences. I asked how C storage in different plant tissues relates to shade tolerance in temperate forests with contrasting climates and physiognomies, and whether relationships vary during the growing season.

METHODS: In the late spring and late summer, I harvested seedlings of eight species with contrasting light requirements from the understory of a cold rainforest and a Mediterranean forest in Chile. Nonstructural carbohydrate (NSC) concentrations and pools (i.e., biomass x NSC concentration) were determined in leaves, aboveground wood, and roots. The effects of shade tolerance and sampling date on the NSCs were analyzed for each forest and tissue with linear mixed-effects models.

KEY RESULTS: In both forests, concentrations of NSC and soluble sugars in woody tissues, as well as fractions of NSC in these tissues, were lower in shade tolerant than in shade intolerant species. For root NSC concentrations, these trends depended on the sampling date: in the late spring the concentrations were similar in shade tolerant and intolerant species, while in the late summer they were lower in shade tolerant species.

CONCLUSIONS: Shade tolerance is not linked to C storage in the two studied forests, suggesting that allocation to growth or defenses could be more advantageous for low light persistence. Alternatively, high levels of C storage could be also selected in shade intolerant species to face herbivory or drought.

For further details log on website :
http://www.amjbot.org/content/102/9/1442.abstract