Variation in benthic metabolism and nitrogen cycling across clam aquaculture sites

MARINE POLLUTION BULLETIN

卷:127

Article

Murphy, Anna E.¹  Nizzoli, Daniele²  Bartoli, Marco^2,3  Smyth, Ashley R.⁴  Castaldelli, Giuseppe⁵  Anderson, Iris C.¹ 

[1] Coll William & Mary, Virginia Inst Marine Sci, Gloucester Point, VA 23062 USA

[2] Univ Parma, Dept Chem Life Sci & Environm Sustainabil, Parco Area Sci 11-A, I-43124 Parma, Italy

[3] Klaipeda Univ, LT-92294 Klaipeda, Lithuania

[4] Univ Florida, Inst Food & Agr Sci, Ctr Trop Res & Educ, Soil & Water Sci Dept, Homestead, FL 33031 USA

[5] Ferrara Univ, Dept Life Sci & Biotechnol, Ferrara, Italy

关键词: Denitrification;    DNRA;    Nitrification;    Nitrate respiration;    Clam aquaculture;    Nitrogen cycling;   

DOI  :  10.1016/j.marpolbul.2017.12.003

来源: Elsevier

【 摘 要 】

As bivalve aquaculture expands globally, an understanding of how it alters nitrogen is important to minimize impacts. This study investigated nitrogen cycling associated with clam aquaculture in the Sacca di Goro, Italy (Ruditapes philipinarum) and the Eastern Shore, USA (Mercenaria mercenaria). Ammonium and dissolved oxygen fluxes were positively correlated with clam biomass; R. philippinarum consumed 6 times more oxygen and excreted 5 times more NH4+ than M. mercenaria. There was no direct effect of clams on denitrification or dissimilatory nitrate reduction to ammonium (DNRA); rather, nitrate availability controlled the competition between these microbial pathways. Highest denitrification rates were measured at sites where both water column nitrate and nitrification were elevated due to high densities of a burrowing amphipod (Corophium sp.). DNRA exceeded denitrification where water column nitrate was low and nitrification was suppressed in highly reduced sediment, potentially due to low hydrologic flow and high clam densities.

【 授权许可】

Free