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
    
    • MH11 : Arctic neuston
      
    • MH12 : Atlantic neuston
      
    • MH13 : Baltic neuston
      
    • MH14 : Black Sea neuston
      
    • MH15 : Mediterranean neuston
      
      • MH151 : Mediterranean temporary neuston layer
        
      • MH152 : Mediterranean permanent neuston layer
        
  • 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
      
      • MH221 : Atlantic completely mixed water column with reduced salinity and short residence time
        
      • MH222 : Atlantic completely mixed water column with reduced salinity and medium residence time
        
      • MH223 : Atlantic completely mixed water column with reduced salinity and long residence time
        
    • MH23 : Baltic completely mixed water column with reduced salinity
      
      • MH231 : Baltic completely mixed water column with reduced salinity and short residence time
        
      • MH232 : Baltic completely mixed water column with reduced salinity and medium residence time
        
      • MH233 : Baltic completely mixed water column with reduced salinity and long residence time
        
    • MH24 : Black Sea completely mixed water column with reduced salinity
      
      • MH241 : Black Sea completely mixed water column with reduced salinity and short residence time
        
      • MH242 : Black Sea completely mixed water column with reduced salinity and medium residence time
        
      • MH243 : Black Sea completely mixed water column with reduced salinity and long residence time
        
    • 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
    
  • MH6 : 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
    
    • MHA1 : Arctic fronts in full salinity water column
      
    • MHA2 : Atlantic fronts in full salinity water column
      
    • MHA3 : Baltic fronts in full salinity water column
      
    • MHA4 : Black Sea fronts in full salinity water column
      
    • MHA5 : Mediterranean fronts in full salinity water column
      
• MJ : Ice-associated marine habitats
  
  • MJ1 : Sea ice
    
  • MJ2 : Freshwater ice
    
  • MJ3 : Brine channels
    
    • MJ31 : Arctic brine channels
      
    • MJ32 : Baltic brine channels
      
  • MJ4 : Under-ice habitat
    
• N : Coastal habitats
  
• Q : Wetlands
  
• R : Grasslands and lands dominated by forbs, mosses or lichens
  
• 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
    
  • U6 : Recent volcanic features
    
• V : Vegetated man-made habitats