Abstract
We examined the decay of chlorophyll a and the carotenoid fucoxanthin in oxic and anoxic sediment microcosms, with and without the deposit-feeding benthic amphipod Monoporeia affinis, over 57 days at 5 degrees C. Deep frozen phytoplankton from the Baltic Sea proper was added to all but a few microcosms. The range of chlorophyll a and fucoxanthin decay rate constants observed in microcosms with phytoplankton addition was 0.04-0.07 day(-1). The fastest pigment decay and build-up of chlorophyll breakdown products after phytoplankton addition were found in oxic treatments with amphipods. No effects of amphipods on pigment breakdown were found in anoxic treatments, or in treatments without phytoplankton addition. Greater losses of chlorophyll a in oxic (96%) than in anoxic (80%) treatments after 57 days indicates that preservation of sedimentary organic matter will be enhanced during periods of anoxia. Due to slow recruitment and recolonization in Baltic sediments, a single anoxic event may cause long-term (years) absence of significant macrobenthos. Anoxic events will thus not only reduce decay of plant pigments, and presumably other organic matter, while they last, but will also have longer-term effects, through elimination of macrofauna, which when present enhance organic matter decomposition.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Journal of experimental marine biology and ecology
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
