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
      
      • MH141 : Black Sea temporary neuston layer
        
      • MH142 : Black Sea permanent neuston layer
        
    • MH15 : Mediterranean 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
    
  • 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
  
  • 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
  
  • 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
    
    • 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
      
      • R541 : Sub-Atlantic Pteridium aquilinum fields
        
      • R542 : Macaronesian Pteridium aquilinum fields
        
      • R543 : Supra-Mediterranean Pteridium aquilinum fields
        
    • R55 : Lowland moist or wet tall-herb and fern fringe
      
    • R56 : Montane to subalpine moist or wet tall-herb and fern fringe
      
      • R561 : Alpic tall-herb communities
        
      • R562 : Alpic tall grass communities
        
      • R563 : Pyreneo-Iberian tall-herb communities
        
      • R564 : Ibero-Mauritanian tall-herb communities
        
      • R565 : Corsican Cymbalaria tall-herb communities
        
      • R566 : Corsican Doronicum tall-herb communities
        
      • R567 : Eastern oro-Mediterranean and Balkan tall-herb communities
        
      • R568 : Alpine Rumex communities
        
      • R569 : Oro-boreal tall-herb communities
        
      • R56A : Ponto-Caucasian tall-herb communities
        
      • R56B : Alpine and subalpine fern stands
        
    • 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
    
  • U6 : Recent volcanic features
    
• V : Vegetated man-made habitats