Dissolved organic matter water column and benthic boundary layer of Roskilde Fjord, Vistula, Öre estuaries, Curonian Lagoon sampled 2014-2017

This compilation gives an overview of the datasets gathered from DOM (DOC, DON, DOP) surveys in the Baltic Sea for the period 2014-2017 discussed in the paper Voss et. al. 2020 (doi:10.1007/s10533-020-00703-5). Sampling took place in the Roskilde Fjord, Vistula and Öre estuaries and Curonian Lagoon during a series of field campaigns by different research groups around the Baltic Sea and subsequently were analysed with comparable internationally standardized methods. Most DOC and DON were measured at the Technical University of Denmark, except samples from the Curonian Lagoon were measured at Klaipeda University, and DON samples from Vistula and Öre estuaries at the IOW. The pre-filtration was in most cases done with 0.2µm filters but sometimes GF/F filters with a nominal pore size of 0.7µm were used. Near bottom samples in Vistula and Öre estuaries were collected from clear water overlying the sediments but often showed elevated particulate matter concentrations. These data sets were treated separately as bottom boundary layer (BBL) data. The data collected during the surveys allows a cross-system comparison, exemplarily for the Baltic Sea, under a wide range of hydrological and environmental situations to test the hypothesis that rivers act as characteristic DOM source – depending on land use in the catchment - which is modified along a salinity gradient from the river offshore.