Norra Dragsviken is a small bay, north of Kalmar in the Kalmar Strait between the Swedish mainland and the island of Öland. It consists of three smaller bays that are separated by narrow lands strips. A little creek, Snärjebäcken, that runs through farmlands and also passes a fish farm is entering one of the smaller bays whilst the east part of Norra Dragsviken is open to the Kalmar Strait. People have been living around Norra Dragsviken for a long time, and it has become evident that this impact on the bay has caused large changes in the ecosystem.
In the summer of 2017, students and researchers from Linnaeus University’s summer course “Discovery of a Sustainable Baltic Sea” teamed up with locals from around Norra Dragsviken. An international group from Sweden, Great Britain, the Netherlands, China, USA, France and Pakistan set out in boats and completed an inventory of biological and chemical parameters. The exercise was an effort to compile data that sheds light on the ecological status of Norra Dragsviken, at the same time giving the students an opportunity to get hands-on practice and collaborate with residents to work locally on a problem that is global.
What did we find out?
Results from 2017 years survey revealed that nitrogen and silicate were higher near the mouth of the little creek, whilst phosphorous seemed to be higher further out, closer to the Kalmar Strait. Heavy metals in the sediment were consistent between the stations and bays, where most of the heavy metals were at elevated levels, and many of those were above target values. Tin compounds, which have been used in antifouling paint on boats, were well over threshold levels and highest in the bay where water circulation is poor. Macroalgae and plant growth in sediment differed between sampling stations and in different types of sediment. Certain stations were composed of stone and compact sediment while others had a large amount of fine particles, sand and degraded material. Further observations made during sampling showed a clear difference in the presence of reeds between stations.
Plans for the future
In March of 2018, all residents around Norra Dragsviken met with Kalmar Municipality, Kalmar County Administrative Board, Norra Möres Watercouncil and Linnaeus University to discuss the findings from the summer of 2017 as well as the plan for 2018 and the future. For instance, a sampling similar to the first year will take place with students from 2018 years summer course. In addition, the implementation of the smart buoys to assess the hydrology of the bays was presented. The ultimate aim of the project is to collect as much information as possible to determine the status of the bay, and to develop measures that can be taken to restore Norra Dragsviken to the bay that it once was. Simultaneously, undergraduate students at LNU will receive hands-on experience in using field sampling and lab methods and working with a real community to improve a problem in society. Sustainability outreach at its finest!
— Caroline Littlefield and Emil Fridolfsson