News
Intensive and successful Research week on SLU's ship R/V Svea
Published: 08 November 2021
How does the stratification of water masses look like, how does ship traffic affect natural hydrography and how does trawling affect benthic organisms and the turnover of nutrients? October 24-30 was the Research week on R/V Svea. Three teams from six universities have come together on board during a content-rich expedition that has been going on around the clock, and where the ship's state-of-the-art equipment has been used to the maximum.
See pictures below.
The research week in the Kattegat is the first of its kind, but SLU's Ship Management Unit (SMU) hopes that the concept will continue.
- We have had a great week characterized by good cooperation both between the research teams and with the crew. We at the SMU really feel that we have achieved the purpose of our Research week; to show how we can coordinate projects between universities and effectively carry out expeditions. We have given several researchers the opportunity to come out on R/V Svea and take part in the resources the ship can offer, says Mattias Sköld who has been the expedition leader and is the research coordinator at the SMU at SLU.
Three research projects with participants from Stockholm and Gothenburg universities, Chalmers University of Technology, University of New Hampshire USA, SMHI and SLU participated in this first research week on board R/V Svea. The expedition has been going on around the clock in the eastern Kattegat with two work teams in twelve-hour shifts.
- The projects have been allocated opportunities to participate based on scientific merit, feasibility and opportunities for coordination between the projects. In the long run, we hope that the financing of ship time can be secured so that we can make regular announcements of expeditions like this, says Mattias Sköld.
Svea's high-resolution echo sounders - for better understanding of stratification structure of water masses
The "Kattegat Sea Laboratory Acoustic Team" worked with the state-of-the-art echo sounders suite mobilized on RV Svea’s drop-keels. The goal of this team was to describe and model the structure of the water column (stratification structure) in the Kattegat, by combining the high-resolution a broadband and multi-beam echo sounder data with directly measured seawater density and sound speed profiles. Water column stratification structure influences vertical transport and exchange of nutrients, carbon, heat and oxygen in the seas such as the Kattegat and the Baltic Sea.
Environmental impact of the intense ship traffic in the Kattegat was studied with advanced measuring moorings
The Ship Wake project have studied how turbulence from ship wakes affects the spread of pollutants and the natural hydrography in areas with intense ship traffic. In the beginning of the expedition, two underwater rigs with current meters (ADCP), autonomous broadband echosounders, and salinity and temperature sensors were placed on the seafloor under the shipping lane, west of the Fladen offshore bank. The instruments continuously collected data for nearly 4 days. During this period, controlled passages with R/V Svea were performed Additionally, utilizing R/V Svea’s hull-mounted broadband echosounders and current meter. In order to measure the stratification in the water, several CTD-profiles have also been made close to the instruments. To compare the conditions inside the shipping lane and the surrounding water, R/V Svea’s Ferry Box system has been on during the entire expedition, continuously measuring parameters such as salinity, temperature and oxygen concentration. Water and sediment samples were also taken in the shipping lane to measure the concentration of pollutants related to shipping, which will be used to estimate the contribution and spread of pollutants from shipping lanes.
The effects of bottom trawling on benthic organisms and nutrient turnover
One of the teams studied if fishing with bottom trawls in the Kattegat affects biological, chemical and physical characteristics of the seafloor - these influence the function of the ecosystem as a suitable habitat for marine life and affect carbon and nutrient cycling between the sediment and the water. Samples were taken using grabs and corers in areas that are trawled at different intensities, including untrawled sites in the nature reserve Skånska Kattegat to serve as a reference area. A refrigerated container on the aft deck was used as a small laboratory where nutrient fluxes and animal activity were measured in sediment cores. In the ship’s lab, the group made precision measurements of sediment oxygen penetration.
Notes
1. https://en.wikipedia.org/wiki/Rosette_sampler
2. https://amloceanographic.com/moving-vessel-profiler/
3. https://www.ferrybox.com/about/principle/index.php.en?print
The team in project "Ship wake" rejoiced at the salvage of their instruments that had been moored on the seabed during four days collecting data from the traffic zone west of Fladen. Photo: Mattias Sköld.
Photo: Mattias Sköld.
The participants of the Research Week 2021. Photo: Mats Wallin.
"Kattegat Sea Laboratory Acoustic Team": Tom Weber, University of New Hampshire USA (UNH), Christian Stranne, Stockholm University (SU), Michael Smith, UNH, Elizabeth Weidner, UNH and Julia Muchowski, SU, in front of ongoing measurements with the broadband echosounder EK80. Photo: Mattias Sköld.
Profiles in an east-west direction across the Kattegat. The upper panel shows sonar data from the sonar transducer for 120 kHz, in the middle temperature and at the bottom salinity from measurements with MVP (a free-falling CTD that hangs in the stern of R/V Svea). Graphics: Elizabeth Weidner.
Measurements and water sampling were made with high resolution using the CTD rosette. Photo: Mattias Sköld.
”The "Shipwake team": Christian Stranne, Stockholm University (SU), Bengt Liljebladh, University of Gothenburg, Julia Muchowski, SU and Amanda Nylund, Chalmers University of Technology. Photo: Mats Wallin
The team "Effects of fishing on wildlife and nutrient turnover" Mattias Sköld, SLU, Claudia Morys Stockholm University, SU, Clare Bradshaw, SU, Serena Albert, SU and Adele Maciute, University of Gothenburg at the sampling point for sediment plugs. Photo: Mats Wallin.
In a temperature controlled laboratory on the aft deck, incubation experiments were performed on sediment samples from areas with different intensities of bottom trawling. Biological activity was measured in sediment cores using a fluorescent tracer. Photo: Mattias Sköld.
Processing a sediment core on the night shift. Photo: Mattias Sköld.
Arctica islandica - The Ocean quahog Hafrún from Iceland (born 1499) died after being put into alcohol 507 years old. It is a record for the world's oldest non-colony forming animals. However, we released these youngsters (50+) back into the Kattegat on their clay bottom at 35 meters depth. Photo: Mattias Sköld.
Read more about R/V Svea and the opportunity to charter her
Read more about R/V Svea on the ship's website. Here you can follow where she is and read about equipment and abilities. You can also see what weeks she is free and costs to charter her.