Seabased Measures in Baltic Sea Nutrient Management. #SEABASED

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1 Seabased Measures in Baltic Sea Nutrient Management #SEABASED

2 P THE SEABASED PROJECT N INTERNAL LOAD IN THE BALTIC SEA The most large-scale problem of the Baltic Sea is eutrophication. While we ve been successful in cutting the nutrient load from land, nutrients that have been stored in the seabed during decades are slowing down the recovery of the Baltic Sea. The SEABASED Project (Seabased Measures in Baltic Sea Nutrient Management) will assess measures that could potentially improve the status of coastal marine areas by reducing the internal load of the sea. Selected measures will also be piloted in small scale in coastal bays in Finland, Åland and Sweden. PHOSPHORUS (P) AND NITROGEN (N) are the main nutrients enhancing the algae growth in the Baltic Sea. In natural conditions, nutrients entering the sea are eventually buried in the bottom sediment, as part of the nutrient cycles in the sea. Problems are arising, when excessive amount of nutrients are entering the sea from human activities, such as agriculture and wastewaters. OUR RESULTS WILL BE u v w Guidelines on Sea-based measures Sustainability assessment A concept for a Water Improvement Fund In addition to piloting new water improvement measures, the project will produce Practical Guidelines on sea-based measures, based on the results and experiences from project pilots. Guidelines will provide information for authorities and policymakers for assessing, selecting and discussing the possibilities of applying seabased measures in water protection policy in the Baltic Sea Region. Commercialization and future financing of seabased measures will be evaluated, if the piloted measures show potential. Based on the environmental assessment of each pilot, criteria for implementation will be set. For future applications, the preconditions for suitable locations will be compiled and financial sustainability, legislative and administrative issues related in implementation of piloted measures will be looked into. A concept for aquatic compensations, based on a Water Improvement Fund, will be developed and tested in Åland with SEABASED pilot measures. The objective of the concept is to define current legislation at different levels, the needs for new regulations and to find functional and sustainable measures that potentially could be utilized in ecosystem-based compensations in the future. The runoff from land has accumulated to the sea during decades and interferes with the natural balance. As a consequence, we see the symptoms of eutrophication: e.g. massive algae blooms and dead, anoxic sea bottoms. In such conditions, the nutrients stored in the seabed are released back to the water, and this is what we call the internal load of the sea. The total land-based phosphorus load to the Baltic Sea is approximately tonnes annually (Helcom, 2017). The current internal phosphorus reserve stored in the sediment and deep waters in the main basin of the Baltic Sea is estimated significant compared to the annual land-based phosphorus load. JUKKA NURMINEN By reducing nutrient runoff from land, the sea will eventually have the possibility to recover. Therefore, the priority should still be in reducing nutrient load from land. It may take some time, even several decades, before considerable positive changes in the environment can be seen. If efficient and applicable, some complementary measures could potentially be taken into use locally in the marine coastal areas. Seabased measures can only be efficient if external load is reduced.

3 ROSITA BROSTRÖM ECOSYSTEM restoration measures will be implemented in Åland and Sweden to reduce nutrients from the marine environment and to restore the coastal pilot areas into better condition. One of the piloted measures is harvesting of overdense populations stickleback, which removes nutrients from marine environment but also acts as positive biomanipulation. According to research, there is a correlation between the strong population of predatory fish, zooplankton and water quality. Thus, by harvesting stickleback that feeds on zooplankton and eggs of predatory fish, the project aims at improvements in the coastal ecosystem. PILOT ACTIVITIES IN ÅLAND, FINLAND AND SWEDEN Pilots will provide information on the environmental effect, cost, technical viability, permission practices and overall sustainability of different measures SEABASED PILOT Å L A N D A N D S W E D E N Nutrients from sea to field NUTRIENT-RICH bottom waters will be removed from two eutrophied, semienclosed coastal bays in Åland to test the possibility of recycling nutrients from the sea by utilizing the water for irrigation on fields. An elaborate monitoring program will ensure a thorough evaluation of the activities, including the amount of removed nutrients from the water and the potential effect of brackish water on soil structure. SEABASED PILOT Å L A N D A N D S W E D E N Positive biomanipulation: stickleback harvesting and pike factories In addition, in Östergötland County on the Swedish coast of the Baltic Sea, complementary measures to increase predatory fish stocks are implemented to support ecosystem recovery of selected coastal bays. The construction of artificial reef structures and small-scale wetlands, so called pike factories, aim at improving the condition in pilot bays for spawning and nursery of young generations of pike and other predatory fish. In addition, the underwater vegetation in coastal bays binds nutrient flows coming from land, thus preventing the eutrophying nutrients entering the open sea.

4 Removal of top-layer sediment SEABASED PILOT S W E D E N A N D F I N L A N D Binding phosphorus into sediment GOTLAND MARL for binding phosphorus permanently in the bottom sediment of the sea will be tested at three pilot sites in Sweden and Finland which have anoxic bottoms and are suffering from the internal loading of phosphorus from the sediment. The pilots start with a development phase and laboratory tests, sampling and selecting of the pilot sites and risk assessments. After application, the effects of the measure on phosphorus concentrations as well as on the sediments and biota will be thoroughly monitored and suitability of the measure for further use will be evaluated. TWO PILOTS on removal of organic, oxygenconsuming, active top-layer of bottom sediment will be carried out at two pilot sites in Finland. The main objective of the measure is to remove nutrients and to decrease the organic oxygen consumption processes in the sediment. For the pilots, such coastal anoxic bottom areas will be selected that have been historically under high nutrient load, with little possibilities of significant flora or fauna to survive without restoration measures. ELY CENTRE / IRMA PUTTONEN ELY CENTRE / IRMA PUTTONEN JUKKA NURMINEN SEABASED PILOT F I N L A N D

5 The SEABASED team in Åland in August Welcome to the SEABASED world! Find the names and contact info of the SEABASED team at Miina Mäki SEABASED Project Manager John Nurminen Foundation Tel (0) miina.maki@jnfoundation.fi Follow us on social media #SEABASED Seabased Measures in Baltic Sea Nutrient Management THE PROJECT is led by the John Nurminen Foundation, and project partners are the ELY Centre of Southwest Finland, Government of Åland, the Åland Fishfarmers Association, Stockholm University, and County Administrative Board of Östergötland.The total budget for the project is approximately 2.8 million euros, of which the Interreg Central Baltic programme is financing approximately 2.1 million euros. COVER PHOTO: MIKKO VOIPIO #SEABASED