title: Seasonal nitrogen and phosphorus dynamics during benthic clam and suspended mussel cultivation.
abstract: Effects of suspended mussel and infaunal clam cultivation on sediment characteristics, and benthic organic and inorganic nitrogen and phosphorus fluxes were compared in a shallow coastal lagoon. The two species had different impacts on sediment features, but both created "hotspots" of nutrient fluxes with annual N and P regeneration rates being 4.9 and 13.5 (mussel) and 4.5 and 14.9 (clams) fold greater than those of unfarmed control sediments. Mussel farming also caused considerable nutrient regeneration within the water column with the mussel ropes contributing ∼25% of total inorganic N and P production and at times dominating the sediments (e.g. 95% of SRP production in summer and 45% of DIN production in winter). Such nutrient regeneration rates seriously question the proposal that suspension-feeding bivalves act as a eutrophication buffer, especially during summer when nutrient regeneration rates are maximal, but other nutrient sources (freshwater run-off and unfarmed sediments) are at their lowest.
authors: Department of Environmental Sciences, Parma University, Parco Area delle Scienze 33/A, 43100 Parma, Italy. daniele.nizzoli@nemo.unipr.it
authors: Daniele
authors: D
authors: Nizzoli
authors: David Thomas
authors: DT
authors: Welsh
authors: Pierluigi
authors: P
authors: Viaroli
mesh_terms: D000818:Animals; D017756:Aquaculture / Q000706:statistics & numerical data*; D049872:Bivalvia / Q000254:growth & development*; D005068:Eutrophication; D019015:Geologic Sediments / Q000737:chemistry; D009584:Nitrogen / Q000032:analysis*; D010758:Phosphorus / Q000032:analysis*; D012621:Seasons; D012623:Seawater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014877:Water Pollution, Chemical / Q000706:statistics & numerical data
chemical_list: D014874:Water Pollutants, Chemical; D010758:Phosphorus; D009584:Nitrogen