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
    
  • 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
    
  • MH8 : Unstratified water column with full salinity
    
    • MH81 : Arctic unstratified water column with full salinity
      
    • MH82 : Atlantic unstratified water column with full salinity
      
    • MH83 : Baltic unstratified water column with full salinity
      
    • MH84 : Black Sea unstratified water column with full salinity
      
    • MH85 : Mediterranean unstratified water column with full salinity
      
  • MH9 : Vertically stratified water column with full salinity
    
    • MH91 : Arctic vertically stratified water column with full salinity
      
    • MH92 : Atlantic vertically stratified water column with full salinity
      
      • MH921 : Atlantic water column with ephemeral thermal stratification and full salinity
        
      • MH922 : Atlantic water column with seasonal thermal stratification and full salinity
        
      • MH923 : Atlantic water column with permanent thermal stratification and full salinity
        
      • MH924 : Atlantic water column with ephemeral halocline and full salinity
        
      • MH925 : Atlantic water column with seasonal halocline and full salinity
        
      • MH926 : Atlantic water column with permanent halocline and full salinity
        
      • MH927 : Atlantic water column with ephemeral oxygen stratification and full salinity
        
      • MH928 : Atlantic water column with seasonal oxygen stratification and full salinity
        
      • MH929 : Atlantic water column with permanent oxygen stratification and full salinity
        
    • MH93 : Baltic vertically stratified water column with full salinity
      
    • MH94 : Black Sea vertically stratified water column with full salinity
      
    • MH95 : Mediterranean vertically stratified water column with full salinity
      
  • MHA : Fronts in full salinity water column
    
• MJ : Ice-associated marine habitats
  
• N : Coastal habitats
  
• Q : Wetlands
  
• R : Grasslands and lands dominated by forbs, mosses or lichens
  
  • R1 : Dry grasslands
    
  • R2 : Mesic grasslands
    
  • R3 : Seasonally wet and wet grasslands
    
  • R4 : Alpine and subalpine grasslands
    
  • R5 : Forest fringes and clearings and tall forb stands
    
  • 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
    
    • U31 : Boreal and arctic siliceous inland cliff
      
    • U32 : Temperate high-mountain siliceous inland cliff
      
    • U33 : Temperate, lowland to montane siliceous inland cliff
      
    • U34 : Mediterranean siliceous inland cliff
      
    • U35 : Boreal and arctic base-rich inland cliff
      
    • U36 : Temperate high-mountain base-rich inland cliff
      
    • U37 : Temperate, lowland to montane base-rich inland cliff
      
    • U38 : Mediterranean base-rich inland cliff
      
    • U39 : Boreal ultramafic inland cliff
      
    • U3A : Temperate ultramafic inland cliff
      
    • U3B : Mediterranean ultramafic inland cliff
      
    • U3C : Macaronesian inland cliff
      
    • U3D : Wet inland cliff
      
    • U3E : Limestone pavement
      
  • U4 : Snow or ice-dominated habitats
    
    • U41 : Snow pack
      
    • U42 : Ice cap and glacier
      
    • U43 : Rock glacier and unvegetated ice-dominated moraine
      
  • U5 : Miscellaneous inland habitats usually with very sparse or no vegetation
    
  • U6 : Recent volcanic features
    
• V : Vegetated man-made habitats