title: Resource translocation drives δ(13) C fractionation during recovery from disturbance in giant kelp, Macrocystis pyrifera.
abstract: Resource allocation and translocation are fundamental physiological functions for autotrophs. The mobilization and use of resources drive population dynamics by regulating growth and recovery of individuals, but also influences ecosystem-level processes such as primary productivity and carbon cycling. This study provides the first observation of translocation-driven gradients of δ(13) C in macroalgae, a critically important phenomenon recognized in vascular plants for decades. A ~10‰ δ(13) C increase in new giant kelp (Macrocystis pyrifera) fronds relative to mature canopy blades was produced after 5 weeks following a biomass removal experiment, more than twice the variation typical for macroalgae. The observed δ(13) C patterns are consistent with tissue enrichment following resource translocation in vascular plants. The analogous source-sink relationships and consistent translocation patterns in Macrocystis and vascular plants suggest that translocation of stored resources is critical for structuring productivity and recovery from disturbance in important, habitat-forming macroalgae such as kelps and fucoids.
authors.affiliation: Moss Landing Marine Laboratories, 8272 Moss Landing Road, Moss Landing, California, 95039, USA. mfox@mlml.calstate.edu.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Fox