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    The research programme of Belgica campaign 2014/14 aimed at assessing the different biogeochemical processes controlling the carbon and nitrogen cycles in oligotrophic N.E. Atlantic waters. These cycles are essential components of the ‘biological Carbon Pump' by which part of atmospheric carbon dioxide is transferred to the ocean's interior. Our approach is based on the use of dual nitrate isotope measurements (natural abundance and enrichment experiments) to disentangle these various nitrogen processes in the marine environment, and in particular the process of diazotrophy by which atmospheric N2 is introduced into the oceanic fixed nitrogen reservoir. This input of ‘new' nitrogen should stand in balance with the denitrification process by which nitrogen is lost from the oceanic system. There are indications that the intensity as well as the geographical distribution of diazotrophic activity has been underestimated till date, in general. It is of particular interest to better document diazotrophic activity at latitudes of 38°N and northward, areas for which only few data are available. During the cruise we studied the different biogeochemical processes acting on the marine N-cycle, including N2 fixation, nitrate (NO3-), ammonium (NH4+) and nitrite (NO2-) uptake, nitrification, along a north-south section through the Gulf of Biscaye to Cape Finisterre and further south in open ocean waters along the Iberian peninsula till about 38°30'N. In addition, the effect of iron limitation on the nitrogen fixation and the nitrification processes was investigated.

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    Our project aims at assessing the different biogeochemical processes controlling the nitrogen cycle in oligotrophic N.E. Atlantic waters. Our approach is based on the use of dual nitrate isotope measurements (natural abundance and enrichment experiments) to disentangle these various N processes in the marine environment, and in particular the process of diazotrophy by which atmospheric N2 is introduced into the oceanic fixed nitrogen reservoir. This input of "new" nitrogen should stand in balance with the denitrification process by which N is lost from the oceanic system. There are indications that the intensity as well as the geographical distribution of diazotrophic activity has been underestimated till date. Our observations, made the past few years, indicate that diazotrophic activity is present in the Azores Current region (DIAPICNA, EUROFLEET cruise; July 2011) and along a meridional section through the Atlantic Ocean (EUROPA cruise; European Universities & Research On board RV Polarstern in the Atlantic, Nov. 2012). During the EUROPA cruise maximal fixation rates were observed around 20°N, south of the Canary Islands, but diazotrophic activity was detected at all latitudes, even at 38°N , the northernmost station sampled during the EUROPA cruise. It is of interest to better document diazotrophic activity at latitudes of 38°N and northward. We propose to study the different biogeochemical processes acting on the marine N-cycle, including N2 fixation, along a N-S section through the Gulf of Biscay to Cape Finistere and further south in open ocean waters along the Iberian peninsula till about 36°30'N. On board we will measure primary production, N-nutrient uptake and N2 fixation in the euphotic layer, using 13C, 15N enriched incubation experiments. We also will sample the upper 1000m of water column for nutrient concentration and N-nutrient natural isotopic composition analyses. This investigation will be coupled with a newly started PhD project, financed by FNRS (Aspirant mandate) and in co-tutelle between ULB and VUB, aiming at studying the impact of the marine iron biogeochemistry on the phytoplankton and the diazotroph communities. During the campaign, we shall perform incubation experiments using in-situ oligotrophic surface waters to examine the influence of the addition of dissolved iron and that of natural desert dusts on the phytoplanktonic production and diazotrophic activity.The AUMS project is inspired by the success of similar systems deployed on various ships of opportunity in the framework of the European Union FerryBox project (www.ferrybox.org). The instrumentation will greatly enhance the continuous oceanographic measurements made by RV Belgica by taking advantage of the significant technological improvements since the design of the existing (salinity, temperature, fluorescence) systems. In particular, many new parameters can now be measured continuously including important ecosystem parameters such as nitrate, ammonia, silicate, dissolved oxygen and CO2, turbidity, alkalinity and phytoplankton pigments. In addition, the new equipment allows automatic acquisition and preservation of water samples, rendering RV Belgica operations significantly more efficient by reducing onboard human resources. Data will be available in near real-time via the public website of OD NATURE and following quality control, from the Belgian Marine Data Centre.Collection of GNSS data in the maritime environment for performance evaluation under different conditions.Aim of the project is to cultivate marine bacteria able to degrade hydrocarbons at both atmospheric and high pressure, in aerobic and anaerobic environments. Kill-Spill is an European funded FP7 project focusing on the development of highly efficient, economically and environmentally viable solutions for the clean-up of oil spills caused by maritime transport or offshore oil exploration and related processes. It provides new tools to promote novel (bio)technologies in oi