Key biogeochemical factors affecting soil carbon storage in Posidonia meadows
Serrano, Oscar (Edith Cowan University. Centre for Marine Ecosystems Research)
Ricart, Aurora M. (Edith Cowan University. Centre for Marine Ecosystems Research)
Lavery, Paul S. (Edith Cowan University. Centre for Marine Ecosystems Research)
Mateo, Miguel Angel (Edith Cowan University. Centre for Marine Ecosystems Research)
Arias Ortiz, Ariane (Universitat Autònoma de Barcelona. Institut de Ciència i Tecnologia Ambientals)
Masqué Barri, Pere (Universitat Autònoma de Barcelona. Departament de Física)
Rozaimi, Mohammad (Edith Cowan University. Centre for Marine Ecosystems Research)
Steven, Andy (EcoSciences Precinct. Australia)
Duarte, Carlos M.. (King Abdullah University of Science and Technology)

Date:	2016
Abstract:	Biotic and abiotic factors influence the accumulation of organic carbon (Corg) in seagrass ecosystems. We surveyed Posidonia sinuosa meadows growing in different water depths to assess the variability in the sources, stocks and accumulation rates of Corg. We show that over the last 500 years, P. sinuosa meadows closer to the upper limit of distribution (at 2-4m depth) accumulated 3- to 4-fold higher Corg stocks (averaging 6. 3 kg Corg m¯²/ at 3- to 4-fold higher rates (12. 8 gCorg m¯² yr¯¹/ compared to meadows closer to the deep limits of distribution (at 6-8m depth; 1. 8 kg Corg m¯² and 3. 6 g Corg m¯² yr¯¹/. In shallower meadows, Corg stocks were mostly derived from seagrass detritus (88% in average) compared to meadows closer to the deep limit of distribution (45% on average). In addition, soil accumulation rates and fine-grained sediment content (< 0. 125 mm) in shallower meadows (2. 0mm yr¯¹ and 9 %, respectively) were approximately 2-fold higher than in deeper meadows (1. 2mm yr¯¹ and 5 %, respectively). The Corg stocks and accumulation rates accumulated over the last 500 years in bare sediments (0. 6 kg Corg m¯² and 1. 2 g Corg m¯² yr¯¹/ were 3- to 11-fold lower than in P. sinuosa meadows, while fine-grained sediment content (1 %) and seagrass detritus contribution to the Corg pool (20 %) were 8- and 3-fold lower than in Posidonia meadows, respectively. The patterns found support the hypothesis that Corg storage in seagrass soils is influenced by interactions of biological (e. g. , meadow productivity, cover and density), chemical (e. g. , recalcitrance of Corg stocks) and physical (e. g. , hydrodynamic energy and soil accumulation rates) factors within the meadow. We conclude that there is a need to improve global estimates of seagrass carbon storage accounting for biogeochemical factors driving variability within habitats.
Grants:	Agència de Gestió d'Ajuts Universitaris i de Recerca 2014/SGR-1356
Note:	Unidad de excelencia María de Maeztu MdM-2015-0552
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Published in:	Biogeosciences, Vol. 13, issue 15 (Aug. 2016) , p. 4581-4594, ISSN 1726-4189

DOI: 10.5194/bg-13-4581-2016

15 p, 1.3 MB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Institut de Ciència i Tecnologia Ambientals (ICTA)
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Articles > Published articles