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
      
      • MH111 : Arctic temporary neuston layer
        
      • MH112 : Arctic permanent neuston layer
        
    • MH12 : Atlantic neuston
      
    • MH13 : Baltic neuston
      
    • MH14 : Black Sea neuston
      
    • MH15 : Mediterranean neuston
      
  • MH2 : 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
    
    • MH61 : Arctic vertically stratified water column with reduced salinity
      
    • MH62 : Atlantic vertically stratified water column with reduced salinity
      
      • MH621 : Atlantic water column with ephemeral thermal stratification and reduced salinity
        
      • MH622 : Atlantic water column with seasonal thermal stratification and reduced salinity
        
      • MH623 : Atlantic water column with permanent thermal stratification and reduced salinity
        
      • MH624 : Atlantic water column with ephemeral halocline and reduced salinity
        
      • MH625 : Atlantic water column with seasonal halocline and reduced salinity
        
      • MH626 : Atlantic water column with permanent halocline and reduced salinity
        
      • MH627 : Atlantic water column with ephemeral oxygen stratification and reduced salinity
        
      • MH628 : Atlantic water column with seasonal oxygen stratification and reduced salinity
        
      • MH629 : Atlantic water column with permanent oxygen stratification and 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
      
      • MH651 : Mediterranean water column with ephemeral thermal stratification and reduced salinity
        
      • MH652 : Mediterranean water column with seasonal thermal stratification and reduced salinity
        
      • MH653 : Mediterranean water column with permanent thermal stratification and reduced salinity
        
      • MH654 : Mediterranean water column with ephemeral halocline and reduced salinity
        
      • MH655 : Mediterranean water column with seasonal halocline and reduced salinity
        
      • MH656 : Mediterranean water column with permanent halocline and reduced salinity
        
      • MH657 : Mediterranean water column with ephemeral oxygen stratification and reduced salinity
        
      • MH658 : Mediterranean water column with seasonal oxygen stratification and reduced salinity
        
      • MH659 : Mediterranean water column with permanent oxygen stratification and reduced salinity
        
  • MH7 : 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
    
    • 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