Typology of surface waters

Finland’s surface water bodies – rivers, lakes and coastal waters – have been classified into different types according to their geographical and natural characteristics. Such a classification is needed to ensure that suitable qualitative goals can be defined for the various types of water body on the basis of their respective natural conditions. Important factors applied in this classification include predominant soil types in catchment areas (peat, mineral soils, clay), the size of the water body (lakes and rivers), depth and water retention span (lakes).

Key parameters applied in defining types of coastal water include salinity, the density of islands, extent of winter ice cover, depth, and rate of water exchange (prevailing current conditions), as well as information on marine fauna, applied to give the classification an ecological dimension.

River types

  1. Small peatland rivers
  2. Small rivers in regions with mineral soils
  3. Small rivers in regions with clay soils
  4. Medium-sized peatland rivers
  5. Medium-sized rivers in regions with mineral soils
  6. Medium-sized rivers in regions with clay soils
  7. Large peatland rivers
  8. Large rivers in regions with mineral soils
  9. Large rivers in regions with clay soils
  10. Very large peatland rivers
  11. Very large rivers in regions with mineral soils

River typology in Finland

© SYKE

Link to a more detailed picture:
River_typology.pdf

Lake types

  1. Small and medium-sized humus-poor lakes
  2. Small humic lakes
  3. Medium-sized humic lakes
  4. Large humus-poor lakes
  5. Large humic lakes
  6. Humus-rich lakes
  7. Shallow humus-poor lakes
  8. Shallow humic lakes
  9. Shallow humus-rich lakes
  10. Lakes with very short water retention  
  11. Lakes in N. Lapland
  12. Nutrient-rich and calcium-rich lakes

Lake typology in Finland

© SYKE

Link to a more detailed picture:
Lakes_typology.pdf

Coastal water types

  1. Gulf of Finland inner archipelago
  2. Gulf of Finland outer archipelago
  3. Southwestern inner archipelago  
  4. Southwestern middle archipelago 
  5. Southwestern outer archipelago 
  6. Bothnian Sea inner coastal waters
  7. Bothnian Sea outer coastal waters
  8. Quark inner archipelago
  9. Quark outer archipelago
  10. Bothnian Bay inner coastal waters
  11. Bothnian Bay outer coastal waters

Coastal water types in Finland

© SYKE

Link to a more detailed picture:
Coastal waters_typology.pdf

More information:
Senior Researcher Ansa Pilke, Finnish Environment Institute (SYKE), firstname.surname@environment.fi
Senior Researcher Pirkko Kauppila, Finnish Environment Institute (SYKE), firstname.surname@environment.fi

Published 2013-09-18 at 14:26, updated 2015-04-30 at 13:42