کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4531671 | 1626106 | 2015 | 12 صفحه PDF | دانلود رایگان |

• We measured benthic nitrogen and oxygen fluxes in situ in the southern North Sea.
• Large differences in benthic fluxes were observed over seasonal time scales.
• Large differences were observed over small spatial scales.
• Benthic macrofauna and temperature had a pronounced impact on benthic fluxes.
• Benthic recycling efficiencies of nitrogen and carbon were estimated.
Benthic oxygen and nitrogen fluxes were quantified within the years 2012 to 2014 at different time series sites in the southern North Sea with the benthic lander NuSObs (Nutrient and Suspension Observatory). In situ incubations of sediments, in situ bromide tracer studies, sampling of macrofauna and pore water investigations revealed considerable seasonal and spatial variations of oxygen and nitrogen fluxes.Seasonal and spatial variations of oxygen fluxes were observed between two different time series sites, covering different sediment types and/or different benthic macrofaunal communities. On a sediment type with a high content of fine grained particles (<63 µm) oxygen fluxes of −15.5 to −25.1 mmol m−2 d−1 (June 2012), −2.0 to −8.2 mmol m−2 d−1 (March 2013), −16.8 to −21.5 mmol m−2 d−1 (November 2013) and −6.1 mmol m−2 d−1 (March 2014) were measured. At the same site a highly diverse community of small species of benthic macrofauna was observed. On a sediment type with a low content of fine grained particles (<63 µm) high oxygen fluxes (−33.2 mmol m−2 d−1 August 2012; −47.2 to −55.1 mmol m−2 d−1 November 2013; −16.6 mmol m−2 d−1 March 2014) were observed. On this sediment type a less diverse benthic macrofaunal community, which was dominated by the large bodied suspension feeder Ensis directus, was observed.Average annual rain rates of organic carbon and organic nitrogen to the seafloor of 7.44 mol C m−2 y−1 and 1.34 mol N m−2 y−1 were estimated. On average 79% of the organic bound carbon and 95% of the organic bound nitrogen reaching the seafloor are recycled at the sediment–water interface.
Journal: Continental Shelf Research - Volume 106, 1 September 2015, Pages 118–129