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
      
      • 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
    
    • MH41 : Arctic partially mixed water column with reduced salinity and medium or long residence time
      
    • MH42 : Atlantic partially mixed water column with reduced salinity and medium or long residence time
      
    • MH43 : Baltic partially mixed water column with reduced salinity and medium or long residence time
      
    • MH44 : Black Sea partially mixed water column with reduced salinity and medium or long residence time
      
      • MH441 : Black Sea partially mixed water column with reduced salinity and medium residence time
        
      • MH442 : Black Sea partially mixed water column with reduced salinity and long residence time
        
    • MH45 : Mediterranean 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
      
    • 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
    
    • MH91 : Arctic vertically stratified water column with full salinity
      
    • MH92 : Atlantic vertically stratified water column with full salinity
      
    • MH93 : Baltic vertically stratified water column with full salinity
      
      • MH931 : Baltic water column with ephemeral thermal stratification and full salinity
        
      • MH932 : Baltic water column with seasonal thermal stratification and full salinity
        
      • MH933 : Baltic water column with permanent thermal stratification and full salinity
        
      • MH934 : Baltic water column with ephemeral halocline and full salinity
        
      • MH935 : Baltic water column with seasonal halocline and full salinity
        
      • MH936 : Baltic water column with permanent halocline and full salinity
        
      • MH937 : Baltic water column with ephemeral oxygen stratification and full salinity
        
      • MH938 : Baltic water column with seasonal oxygen stratification and full salinity
        
      • MH939 : Baltic water column with permanent oxygen stratification and full salinity
        
    • MH94 : Black Sea vertically stratified water column with full salinity
      
      • MH941 : Black Sea water column with ephemeral thermal stratification and full salinity
        
      • MH942 : Black Sea water column with seasonal thermal stratification and full salinity
        
      • MH943 : Black Sea water column with permanent thermal stratification and full salinity
        
      • MH944 : Black Sea water column with ephemeral halocline and full salinity
        
      • MH945 : Black Sea water column with seasonal halocline and full salinity
        
      • MH946 : Black Sea water column with permanent halocline and full salinity
        
      • MH947 : Black Sea water column with ephemeral oxygen stratification and full salinity
        
      • MH948 : Black Sea water column with seasonal oxygen stratification and full salinity
        
      • MH949 : Black Sea water column with permanent oxygen stratification and 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
  
• 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