About the projectIDEAL: Investigation of seasonal variability of the water column and sediment DEnitrification and Anammox in the BaLtic Sea
Denitrification and anammox are the major N-removal pathways in the water column and sediments in the Baltic Sea, yet denitrification rates are usually higher than anammox. Recently, it has been postulated that the N-removal via sedimentary denitrification is not high enough to balance all N inputs. The situation might exacerbate if the extension of the anoxic bottom areas continues. The question that needs to be answered is whether the pronounced increase of water column denitrification will be high enough to compensate for the reduction of N-removal via sediments. As denitrification depends on the substrate availability, water column denitrification will change seasonally due to the variable supply of electron donors such as organic matter, iron, sulfur compounds, etc. This can also affect surface sediments. However, the seasonality of denitrification has not been deeply studied in the Baltic Sea, similarly to the seasonal activity of the microbial communities that mediate denitrification and anammox. The general lack of comprehensive studies towards understanding the N-cycle has hindered our comprehension of the marine ecosystem functioning.
We hypothesize that The microbial activity and accompanied N-removal processes change seasonally both in the water column and surface sediments due to variable substrate availability.
Project beginning: 2020-03-31
Project duration: 48 months
Project budget: 2 431 000 PLN