Examining the production, export, and immediate fate of kelp detritus on open-coast subtidal reefs in the Northeast Atlantic

Smale, DA, Pessarrodona, A, King, NG and Moore, PJ 2021 Examining the production, export, and immediate fate of kelp detritus on open-coast subtidal reefs in the Northeast Atlantic. Limnology and Oceanography. https://doi.org/10.1002/lno.11970

Text 10.1002/lno.11970 Available under License Creative Commons Attribution. Download (351kB)

Abstract/Summary

Kelp forests are highly productive coastal habitats and are emerging as important sources of organic matter for other ecosystems. Although their high rates of productivity and detritus release are expected to lead to substantial export of carbon, few studies have actually quantified rates of export or the persistence of detritus. We addressed this in eight subtidal kelp forests (Laminaria hyperborea) spanning the length (9° of latitude) of the United Kingdom. Specifically, we quantified detritus production, retention/export from source and adjacent habitats, and in situ decomposition rates. Detritus released via both dislodgment of whole plants and “May cast” shedding of old growth was highly variable between sites with greatest values recorded in our colder, northern sites. This was attributable to greater plant size biomass in northern regions, rather than plant density or dislodgement rates. On average, the annual production of kelp detritus was 4706 ± 700 g FW m−2 yr−1 or 301 g C m−2 yr−1. Low retention of detritus within the kelp forest and adjacent sedimentary habitats indicated very high rates of export (> 98% across the study). A litterbag experiment showed detritus may take > 4 months to decompose, suggesting great potential for long distance transport. Overall, our findings suggest that L. hyperborea forests export large amounts of detritus subsidies across their range, which can potentially shape the structure of distant benthic communities and constitute a relevant and largely overlooked flux in the coastal carbon cycle, which may represent an important component of natural carbon sequestration.

Item Type:	Publication - Article
Subjects:	Ecology and Environment Marine Sciences Oceanography
Divisions:	Marine Biological Association of the UK > Other (MBA)
Depositing User:	Tamar Atkinson
Date made live:	09 Feb 2022 14:38
Last Modified:	09 Feb 2024 16:57
URI:	https://plymsea.ac.uk/id/eprint/9550

Actions (login required)

View Item