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
    
    • MH31 : Arctic completely mixed water column with full salinity
      
    • MH32 : Atlantic completely mixed water column with full salinity
      
    • MH33 : Baltic completely mixed water column with full salinity
      
    • MH34 : Black Sea completely mixed water column with full salinity
      
      • MH341 : Black Sea completely mixed water column with full salinity and short residence time
        
      • MH342 : Black Sea completely mixed water column with full salinity and medium residence time
        
      • MH343 : Black Sea completely mixed water column with full salinity and long residence time
        
    • MH35 : Mediterranean 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
      
      • MH511 : Arctic euphotic (epipelagic) zone in unstratified reduced salinity water
        
      • MH512 : Arctic mesopelagic zone in unstratified reduced salinity water
        
      • MH513 : Arctic bathypelagic zone in unstratified reduced salinity water
        
      • MH514 : Arctic abyssopelagic zone in unstratified reduced salinity water
        
    • 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
    
  • 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
  
• N : Coastal habitats
  
• 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
    
    • U21 : Boreal and arctic siliceous scree and block field
      
    • U22 : Temperate high-mountain siliceous scree
      
    • U23 : Temperate, lowland to montane siliceous scree
      
    • U24 : Mediterranean siliceous scree
      
    • U25 : Boreal and arctic base-rich scree and block field
      
    • U26 : Temperate high-mountain base-rich scree and moraine
      
      • U261 : Alpine calcschist screes
        
      • U262 : Thlaspi rotundifolium screes
        
      • U263 : Fine calcareous screes
        
      • U264 : Carpathian calcareous screes
        
        • U2641 : West Carpathian calcareous screes
          
        • U2642 : East Carpathian calcareous screes
          
      • U265 : Rhodopide calcareous screes
        
    • U27 : Temperate, lowland to montane base-rich scree
      
    • U28 : Western Mediterranean base-rich scree
      
      • U281 : Cevenno-Proven
        
      • U282 : Pyrenean calcareous screes
        
      • U283 : Oro-Cantabrian calcareous screes
        
      • U284 : Iberian calciphile fern screes
        
      • U285 : Southern Iberian calcareous screes
        
      • U286 : Central Mediterranean calcareous screes
        
    • U29 : Eastern Mediterranean base-rich scree
      
    • U2A : Crimean base-rich 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