Eutrophication, caused by excess input of nutrients, is one of the main threats affecting the Baltic Sea marine environment. Nutrients enter the Baltic Sea as waterborne (riverine inputs from the catchment area and direct discharges from point and diffuse sources in coastal areas) and airborne (atmospheric deposition) inputs. In 2007 HELCOM adopted a nutrient reduction scheme which is based on maximum allowable nutrient inputs (MAI) to reach "good environmental status" and country-wise nutrient reduction targets (CART) to share the burden of reducing nutrient pollution to the sea (HELCOM Baltic Sea Action Plan). Monitoring of nutrient inputs to the sea is important for assessing progress of countries towards their CART and to evaluate the effectiveness of measures to reduce pollution.

This dataset displays nutrient loading as produced for http://www.helcom.fi/baltic-sea-trends/indicators/inputs-of-nutrients-to-the-subbasins HELCOM Core indicator: Inputs of nutrients to the subbasins based on HELCOM PLC data.

Green colour of PLC subbasin indicates that inputs during 2016 were lower than MAI, red colour when they were higher, while yellow indicates that when taking into account the statistical uncertainty of input data it is not possible to determine whether MAI was fulfilled.

The dataset contains following attributes:

Basin: Name of PLC Subbasin

Maximum allowable nutrient input: Maximum allowable nitrogen input for the subbasin (tons/year)

N input including statistical uncertainty 2016: the average nitrogen input during 2016 including statistical uncertainty (tons/year)

N input 2016 including statistical uncertainty in % of MAI: proportion of normalized nitrogen input during 2016 compared to MAI (%)

Classification of achieving MAI: Classification of achieving MAI is given in colours: green=MAI fulfilled, yellow= fulfilment is not determined due to statistical uncertainty, and red=MAI not fulfilled.