Typology and classification of coastal waters in Estonia Urmas Lips Ministry of Environment, Estonia Estonian Maritime Academy

Work done until now Marine monitoring program Classification Typology Open questions Baltic reference conditions Quality elements and EQRs Time frame for implementation

Monitoring programs: inputs of N and P (atmospheric, riverine and direct loads) concentrations of DIN and DIP, Ntot and Ptot Chl a content (throughout the productive season) species composition, abundance and biomass of phytoplankton (throughout the productive season) species composition, abundance and biomass of phytobenthos (once a year, in July-August) species composition, abundance and biomass of zoobenthos (once a year, late May-early June) oxygen content in the near bottom layer Secchi depth etc.

Eutrophication monitoring stations

Phytobenthos monitoring transects

Development of quality criteria (EISEMM Project) The approach is based on density distributions of observations at the least impacted area (represented by the stations 2 and F3 in the Gulf of Finland), density distributions in the most impacted area (Pärnu Bay, stations K5 and K21) and supplemented with data from an eutrophic Danish estuary (Skive Fjord). On average the Gulf of Finland cannot be considered as constituting the reference conditions for coastal waters. Instead it is suggested that reference conditions may occasionally (i.e. in 20% of observations) be met. Considering the spatial gradients in most pelagic parameters the conditions in the coastal waters cannot be higher than that of the open waters. Hence, it seems logical to establish a linkage between offshore conditions and coastal waters.

Observation in relation to a selected distribution function (EISEMM Project, 2002)

Proposed water quality criteria to be used to identify ecological quality classes (EISEMM Project)

Median values of Ntot seen in relation to the developed water quality criteria (EISEMM Project, 2002)

Median values of TN seen in relation to the developed water quality criteria Adjustment for local conditions (salinity) and for conditions at the open boundaries (EISEMM Project, 2002)

Typology of coastal waters should be based on the following factors: Ecoregion salinity (< 0.5, 0.5 to 5-6, 5-6 to 18-20 etc.) wave exposure (from extremely exposed to very sheltered) depth (< 30 m, > 30 m) mixing (permanently fully mixed, partially stratified, permanently stratified) residence time (days, weeks, months to years) substratum (hard, sand-gravel, mud, mixed sediments) current velocity duration of ice coverage (irregular, < 90 days, 90 to 150 days, > 150 days)

Proposed types of coastal waters

Proposed types of coastal waters

Ongoing work Establishment of type-specific quality criteria (phytobenthos, zoobenthos and phytoplankton) Open questions Baltic reference conditions Time frame for implementation Quality elements and EQRs

Baltic reference conditions - can we take open sea conditions (in the littoral zone of islands) as the reference conditions for the coastal areas? If no, what is then a realistic time frame for implementation? - very long residence time How to derive ecological quality ratios for different water quality elements? - indexes based on species composition, abundance and biomass, key species, etc. How to deal with spatial and temporal variations?

Surface accumulations of blue-green algae in 1997 HELCOM, 2002 Photo: Inga Kanoshina

Variations of salinity and oxygen content in the deep layers of the central Gulf of Finland (HELCOM, 2002)

Variations of DIP in the deep layers and winter nutrient concentrations in the surface layer of the central GOF (HELCOM, 2002)

What is a realistic time frame for implementation? (Elken, 2001)

What are the reference conditions for cyanobacteria blooms? Surface water temperature 10.0-21.6 °C in 1997, 12.3-17.3 °C in 1998 and 13.4-22.1°C in 1999 (Kanoshina et al., 2003)

Future work and research needs (in co-operation with other countries): to establish a typology of coastal waters to define type-specific reference conditions to set ecological quality ratios and to define water quality criteria for different water quality elements and for different types to develop further monitoring and assessment methods (proper equipment and sampling strategies considering wide ranges of natural variability of water quality elements)