EUNIS habitat type hierarchical view (marine version 2022 & terrestrial version 2021)

The EUNIS habitat classification review is on-going. Four groups are pending review: Inland waters, Wetlands, Constructed, industrial and other artificial habitats and Complexes.

• M : Marine benthic habitats (MA-MG)
  
• MH : Pelagic water column
  
  • MH1 : Neuston
    
  • MH2 : Completely mixed water column with reduced salinity
    
    • MH21 : Arctic completely mixed water column with reduced salinity
      
    • MH22 : Atlantic completely mixed water column with reduced salinity
      
    • MH23 : Baltic completely mixed water column with reduced salinity
      
    • MH24 : Black Sea completely mixed water column with reduced salinity
      
    • MH25 : Mediterranean completely mixed water column with reduced salinity
      
  • MH3 : Completely mixed water column with full salinity
    
  • MH4 : Partially mixed water column with reduced salinity and medium or long residence time
    
  • MH5 : Unstratified water column with reduced salinity
    
    • MH51 : Arctic unstratified water column with reduced salinity
      
    • MH52 : Atlantic unstratified water column with reduced salinity
      
    • MH53 : Baltic unstratified water column with reduced salinity
      
    • MH54 : Black Sea unstratified water column with reduced salinity
      
    • MH55 : Mediterranean unstratified water column with reduced salinity
      
  • MH6 : Vertically stratified water column with reduced salinity
    
    • MH61 : Arctic vertically stratified water column with reduced salinity
      
    • MH62 : Atlantic vertically stratified water column with reduced salinity
      
    • MH63 : Baltic vertically stratified water column with reduced salinity
      
    • MH64 : Black Sea vertically stratified water column with reduced salinity
      
    • MH65 : Mediterranean vertically stratified water column with reduced salinity
      
  • MH7 : Fronts in reduced salinity water column
    
    • MH71 : Arctic fronts in reduced salinity water column
      
    • MH72 : Atlantic fronts in reduced salinity water column
      
    • MH73 : Baltic fronts in reduced salinity water column
      
    • MH74 : Black Sea fronts in reduced salinity water column
      
    • MH75 : Mediterranean fronts in reduced salinity water column
      
  • MH8 : Unstratified water column with full salinity
    
  • MH9 : Vertically stratified water column with full salinity
    
  • MHA : Fronts in full salinity water column
    
• MJ : Ice-associated marine habitats
  
  • MJ1 : Sea ice
    
  • MJ2 : Freshwater ice
    
  • MJ3 : Brine channels
    
  • MJ4 : Under-ice habitat
    
• N : Coastal habitats
  
• R : Grasslands and lands dominated by forbs, mosses or lichens
  
  • R1 : Dry grasslands
    
  • R2 : Mesic grasslands
    
    • R21 : Mesic permanent pasture of lowlands and mountains
      
      • R211 : Unbroken pastures
        
        • R2111 : Ryegrass pastures
          
        • R2112 : Atlantic Cynosurus-Centaurea pastures
          
        • R2113 : Sub-Atlantic hill pastures
          
        • R2114 : Continental pastures
          
      • R212 : Ditch-broken pastures
        
      • R213 : Abandoned pastures
        
      • R214 : Species-rich lowland flood meadows
        
      • R215 : Macaronesian mesic grassland
        
      • R216 : Boreo-arctic Agrostis-Festuca grasslands
        
    • R22 : Low and medium altitude hay meadow
      
    • R23 : Mountain hay meadow
      
    • R24 : Iberian summer pasture (vallicar)
      
      • R241 : Perennial vallicares
        
      • R242 : Annual vallicares
        
      • R243 : Andalusian Armeria vallicares
        
  • R3 : Seasonally wet and wet grasslands
    
  • R4 : Alpine and subalpine grasslands
    
  • R5 : Forest fringes and clearings and tall forb stands
    
    • R51 : Thermophilous forest fringe of base-rich soils
      
    • R52 : Forest fringe of acidic nutrient-poor soils
      
    • R53 : Macaronesian thermophilous forest fringe
      
    • R54 : Pteridium aquilinum vegetation
      
    • R55 : Lowland moist or wet tall-herb and fern fringe
      
    • R56 : Montane to subalpine moist or wet tall-herb and fern fringe
      
    • R57 : Herbaceous forest clearing vegetation
      
  • R6 : Inland salt steppes and salt marshes
    
  • R7 : Sparsely wooded grasslands
    
• S : Heathland, scrub and tundra
  
• T : Forest and other wooded land
  
• U : Inland habitats with no or little soil and mostly with sparse vegetation
  
  • U1 : Terrestrial underground caves, cave systems, passages and waterbodies
    
  • U2 : Screes
    
  • U3 : Inland cliffs, rock pavements and outcrops
    
  • U4 : Snow or ice-dominated habitats
    
  • U5 : Miscellaneous inland habitats usually with very sparse or no vegetation
    
    • U51 : Fjell field
      
    • U52 : Polar desert
      
    • U53 : Glacial moraines with very sparse or no vegetation
      
  • U6 : Recent volcanic features
    
• V : Vegetated man-made habitats