Sedimentary trace metals: unlocking the archives of coastal marine hypoxia (Academy of Finland Research Fellowship)

"Dead zones" are areas of the ocean where the water contains no oxygen, and most marine organisms cannot survive. These zones are increasingly common in coastal areas of Europe, including the Baltic Sea, where inputs of waste water and agricultural runoff have caused widespread eutrophication. It is important to know how dead zones have expanded in the past, in order to estimate sustainable inputs of nutrients for the future. Unfortunately, many coastal areas have not been monitored sufficiently well to provide this information. This project will fill in these gaps by studying sediment cores from coastal regions of Europe. Using advanced chemical analyses, the project will focus on "trace" metals in sediments, which provide a natural archive of the size of dead zones in the past. New information about the past expansion of dead zones will be used to improve existing models of nutrient cycling in the Baltic Sea.