| Fieldname | Explanation |
| Marine habitats | All saltwater habitats, benthic and pelagic (e.g. Atlantic, North Sea, Barents Sea) |
| Estuaries and brackish areas | Where freshwater meets the sea, and where salinity varies between 35 ppm and <5 ppm (such as the Baltic Sea) |
| Lakes | Freshwater bodies (stagnant, lentic waters) |
| Watercourses | Running water (lotic waters) |
| Coastland | Along and influenced by the sea |
| Riparian zones | Along rivers |
| Wetlands | Bogs, mires and wet grasslands, lakeshores |
| Urban areas | Near human dvellings |
| Agricultural areas | Under cultivation |
| Disturbed areas | Under human influence, but not under cultivation |
| Boreal forest | Conifer forest (Neddleleaf) |
| Mixed conifer/broadleaf forest | Conifers (Neddleleaf) mixed with decidous trees |
| Temperate broadleaf forest | Decidous forests |
| Grass and heathlands | Dry grassland incl. steppe/prarie and heathland |
| Arctic/alpine | Arctic/alpine vegetation types (latitude and altitude aspects involved) |
| Continental ice | e.g. the glaciers on Greenland |
| Rocks and lavafields | Rocky areas without natural vegetation or with very sparse vegetation |
| Host | Organism were the IAS gets protection or nourishment |
| Vector | The bearer or carrier of pathogenic IAS |
| Not known | |
| Greenhouses or compost heaps | Here the climate is regulated to natural situation (temperature and humidity) |
| Under human management | Inside houses and warehouses, inside furfarms, in closed aquacultural sites, in closed aquaria |
| Shrublands | Shrubs and dwarfed trees |
