Baltic Marine Environment
Protection Commission

Accounting for extra reductions

In the Ministerial Declaration 2013 the Contracting Parties agreed that the countries can account for extra reductions, in proportion to the effect on a neighbouring basin with reduction targets, in reaching their Country Allocated Reduction Targets.

The Baltic Sea comprises of a series of connected basins, and changes in the environment will lead to changes in adjacent basins as well due to transport of nutrients between the basins. In simple terms, if the nutrient concentrations change in one basin it will cause changes in the nutrient transports to adjacent basins. The magnitude of the nutrient transport change will depend on the water exchange between the basins and concentration difference between the basins. 

Practically, in case the nutrients input to a basin is lower than MAI (extra reduction), fluxes will increase to this basin. It causes improvement of the status in neighbouring basins either. This improvement can be quantified using coefficients called equivalent reduction. The equivalent redaction illustrates environmental effect in the basins neighbouring the one where extra reduction has been achieved. The equivalent reductions are given in the Tables 1 and 2. 

Table 1:  Equivalent reductions on phosphorus. The table should be read so that each row provides the necessary input reduction to the basins to the left to provide the equivalent environmental effect in the basins in the top row, e.g. 1.5 ton reduction to BS gives the same effect in the BP as 1 ton reduction directly to BP. NB! That the factors are valid on single basin pairs under condition that all other basins fulfil MAI.

  KTDSBPBSBBGRGF
KT14.0
DS0.813.2
BP2.42.813.37.73.8
BS3.84.61.512.65.8
BB9.08.31
GR3.64.31.64.816.5
GF3.64.21.34.11

Table 2:  Equivalent reductions on nitrogen. The table should be read so that each row provides the necessary input reduction to the basins to the left to provide the equivalent environmental effect in the basins in the top row, e.g. 1.3 ton reduction to GR gives the same effect in the BP as 1 ton reduction directly to BP. NB! That the factors are valid on single basin pairs under condition that all other basins fulfil MAI.

  KTDSBPBSBBGRGF
KT17.3
DS1.714.6
BP1
BS17.8
BB1.11
GR1.31
GF4.01