Guillermo Francés, a professor and researcher at the Department of Marine Geosciences and Territorial Planning at the University of Vigo, describes the first phase of the Bocats campaign as “very positive”, after the oceanographic ship Sarmiento de Gamboa arrived off the coast of Greenland. A little over a month of navigation through North Atlantic waters in the transect between Vigo and Greenland (OVIDE section) has been completed, in which personnel from the CSIC’s Marine Research Institute in Vigo and Ifremer, together with those from the University of Vigo, measured various physical and chemical properties of the water column (pH, alkalinity, CO2 concentration, oxygen, nutrients, etc.) in 99 stations separated from each other by an average of 30 kilometers, thus fulfilling one of the objectives of the campaign, which is the characterization of water masses along a transect that has been repeated every two years since 2002. “For the first time, in this series of measurements, sediment samples are being obtained at the same points. So far we have recovered sediments at 26 points and in the coming days we will complete the transect by prospecting a minimum of 25 more stations in the Irminger basin”, explains Francés, who is accompanied on behalf of the University of Vigo by fellow researcher Irene Alejo and students Susa Álvarez and Víctor Pelayo.
The surface sediment samples collected at all stations reach a thickness of between 20 and 35 cm. and taking into account that the analyses that the Vigo researchers intend to carry out are of every centimeter, the total number of samples to be studied will exceed 1300. “This implies that the amount of data and information that we will obtain will allow us to carry out a detailed characterization of the sediment and its relationship with the water masses at the bottom”, explains Francés, who highlights the importance of calculating the carbon cycle flows, not being restricted solely to the water column, as occurs in most studies carried out, but rather introducing into the calculation the part that, although minority, not negligible, goes to the sediments or, eventually, that the sediments are returning to the ocean.
The BOCATS campaign, Biennial Observation of Carbon, Acidification, Transport and Sedimentation in the North Atlantic, is a project funded by Mineco with more than 158,000 euros (not including the campaign), led by researcher from the Department of Oceanography of the CSIC’s Marine Research Institute in Vigo, Fiz Fernández.
Arrival in Reykjavík and subsequent analysis of the sediments
After spending a few hours sheltered off the coast of Greenland due to a strong storm, which caused wind gusts of 45 knots and waves of up to five meters, the Sarmiento de Gamboa began a reverse journey, dedicated exclusively to the recovery of bottom sediments, to then face the last days of the campaign that will take place in the section parallel to the Reykjanes ridge and continue the transect (RREX section), following the orientation of this underwater mountain range until ending in the capital of Iceland, where they expect to arrive at the end of the month.
“Once the BOCATS campaign is over and once on land, all sediment analyses are the responsibility of the XM1 group, not only of the researchers we embarked on, but of the rest of the team. This includes analyses of grain size, composition, organic matter content, microfossils and sediment dating”, details the researcher from the Department of Marine Geosciences and Land Use Planning about the work that awaits them and whose results will be related to those obtained in the water column by the IIM and Ifremer group. Likewise, the researchers from the University of Vigo intend to establish collaborations with other groups to carry out other complementary analyses that they are not able to address.
Source DUVI
Mª del Carmen Echevarría | Vigo
