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
    
    • 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
      
      • 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
    
    • 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
      
      • MH331 : Baltic completely mixed water column with full salinity and short residence time
        
      • MH332 : Baltic completely mixed water column with full salinity and medium residence time
        
      • MH333 : Baltic completely mixed water column with full salinity and long residence time
        
    • MH34 : Black Sea completely mixed water column with full salinity
      
    • 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
    
  • 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
      
      • MH821 : Atlantic euphotic (epipelagic) zone in unstratified full salinity water
        
      • MH822 : Atlantic mesopelagic zone in unstratified full salinity water
        
      • MH823 : Atlantic bathypelagic zone in unstratified full salinity water
        
      • MH824 : Atlantic abyssopelagic zone in unstratified full salinity water
        
    • 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
      
      • MH911 : Arctic water column with ephemeral thermal stratification and full salinity
        
      • MH912 : Arctic water column with seasonal thermal stratification and full salinity
        
      • MH913 : Arctic water column with permanent thermal stratification and full salinity
        
      • MH914 : Arctic water column with ephemeral halocline and full salinity
        
      • MH915 : Arctic water column with seasonal halocline and full salinity
        
      • MH916 : Arctic water column with permanent halocline and full salinity
        
      • MH917 : Arctic water column with ephemeral oxygen stratification and full salinity
        
      • MH918 : Arctic water column with seasonal oxygen stratification and full salinity
        
      • MH919 : Arctic water column with permanent oxygen stratification and full salinity
        
    • MH92 : Atlantic vertically stratified water column with 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
      
      • MH951 : Mediterranean water column with ephemeral thermal stratification and full salinity
        
      • MH952 : Mediterranean water column with seasonal thermal stratification and full salinity
        
      • MH953 : Mediterranean water column with permanent thermal stratification and full salinity
        
      • MH954 : Mediterranean water column with ephemeral halocline and full salinity
        
      • MH955 : Mediterranean water column with seasonal halocline and full salinity
        
      • MH956 : Mediterranean water column with permanent halocline and full salinity
        
      • MH957 : Mediterranean water column with ephemeral oxygen stratification and full salinity
        
      • MH958 : Mediterranean water column with seasonal oxygen stratification and full salinity
        
      • MH959 : Mediterranean water column with permanent oxygen stratification and full salinity
        
  • MHA : Fronts in full salinity water column
    
• MJ : Ice-associated marine habitats
  
  • MJ1 : Sea ice
    
    • MJ11 : Arctic sea ice
      
    • MJ12 : Baltic 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
    
  • 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
  
• V : Vegetated man-made habitats