WP1 - PRODUCTION, EXPORT AND TURN-OVER OF KELP DETRITUS ALONG A WAVE EXPOSURE GRADIENT
Lead: Morten Pedersen, Roskilde University (Denmark)
Objective 1.1. Spatio-temporal quantification of production, turnover and export of kelp detritus. The objective of this WP is to quantify the annual detritus budget associated with Laminaria hyperborea under different wave regimes. Detrital production varies substantially between species (Krumhansl & Scheibling 2012), yet no data exist for L. hyperborea, the dominant kelp in Norway and most of Europe. A key unanswered question concerns the magnitude and relative contribution to detritus production from blade erosion and dislodgement. These processes have different underlying drivers (e.g., phenology, temperature or fouling induced necrocis, water movement) with important implications for the delivery (seasonal timing, predictability, magnitude, export distances) and their sensitivity to environmental change (de Bettignies et al., 2015). This, in turn, has important consequences for the communities which rely on kelp detritus as a resource. Meeting this objective necessitates an intensive field study over 1.5 years, to be conducted in the study area (mouth of Malangen Fjord) and supplemented with laboratory studies on decomposition characteristics (rates and changes in chemical composition of kelp detritus).
Task 1.1. Quantifying the annual kelp detritus budget under different wave regimes
Task 1.2. Determination of decay rate and changes in nutritional value of kelp detritus under various environmental constraints (i.e. temperature, aerobic/anaerobic conditions)
Task 1.3. Quantifying detritus turnover and export from kelp across wave exposure and season.