EUNIS habitat classification
EUNIS (European Nature Information System) provides a hierarchical classification of European terrestrial, freshwater and marine habitats. It was developed to provide a common terminology for habitat description, mapping, monitoring and nature conservation throughout Europe.
Contents
European classification systems
In earlier European nature classification systems, particularly the CORINE Biotopes Classification, the term biotope was widely used. In the subsequent EUNIS classification this terminology was replaced by the term 'habitat type'. EUNIS habitat types can be characterized by both physical environmental conditions and their associated biological communities; biotopes are therefore not distinguished as a separate category.
The EUNIS habitat classification distinguishes broad habitats primarily according to environmental characteristics. At more detailed classification levels, characteristic biological communities are increasingly used to define habitat types. Detailed EUNIS habitat types therefore often correspond to what is termed a biotope: a physical habitat together with its associated biological community.
EUNIS marine classification
In the revised EUNIS marine classification (2022), marine benthic habitats are first distinguished according to major biological zones related to depth:
- MA – Littoral — essentially the intertidal zone
- MB – Infralittoral — permanently submerged shallow seabed, generally within the photic zone
- MC – Circalittoral — deeper shelf seabed below the infralittoral
with further zones extending into deeper offshore and deep-sea environments (MD–MG).
At Level 2, these biological zones are combined with substrate or structural habitat type. For example, the littoral habitats comprise:
- MA1 – Littoral rock
- MA2 – Littoral biogenic habitat
- MA3 – Littoral coarse sediment
- MA4 – Littoral mixed sediment
- MA5 – Littoral sand
- MA6 – Littoral mud
The infralittoral follows the same structure, with MB1 rock, MB2 biogenic habitat, MB3 coarse sediment, MB4 mixed sediment, MB5 sand and MB6 mud. At Level 3, habitats are further distinguished according to the major biogeographical regions of European seas (Arctic, Baltic, Atlantic, Mediterranean and Black Sea). At more detailed levels, biological communities and characteristic species increasingly enter the classification.
Coastal habitats above the marine littoral zone, such as coastal dunes and cliffs, are classified separately from marine habitats.
Applications and limitations
The EUNIS habitat classification provides a common framework for describing and mapping habitats throughout Europe. It facilitates comparison and integration of habitat information obtained in different regions and is widely used for habitat inventories and mapping, environmental monitoring and assessment, nature conservation and environmental management[1]. Crosswalks between EUNIS and other European habitat classifications, including the Habitats Directive Annex I habitat types and the European Red List of Habitats, facilitate its use for conservation assessment and environmental policy.
The hierarchical structure allows habitat classification at different levels of detail. In the marine environment, broad habitat classes can often be mapped from physical characteristics such as depth and seabed substrate, whereas classification at more detailed levels generally requires information on the biological community.
Habitat classification nevertheless involves some degree of simplification. Environmental conditions and biological communities often vary gradually in space, whereas a classification divides this variation into discrete habitat types. The resulting habitat boundaries therefore do not necessarily represent sharp ecological boundaries. The habitat type that can be reliably assigned also depends on the spatial scale and resolution of the observations and on the survey method. Acoustic seabed surveys, for example, can provide extensive information on depth and substrate but generally cannot distinguish biological communities required for classification at detailed EUNIS levels[2].
EUNIS is designed as a Europe-wide classification and therefore cannot represent every local or regional variation in habitat characteristics. Classification and habitat maps should consequently be interpreted in relation to the geographical region, classification level, spatial scale and type of observations on which they are based.
External link
Related articles
References
- ↑ Galparsoro, I., Connor, D.W., Borja, A., Aish, A., Amorim, P., Bajjouk, T., Chambers, C., Coggan, R., Dirberg, G., Ellwood, H., Evans, D., Goodin, K.L., Grehan, A., Haldin, J., Howell, K., Jenkins, C., Michez, N., Mo, G., Buhl-Mortensen, P., Pearce, B. and Populus, J. 2012. Using EUNIS habitat classification for benthic mapping in European seas: Present concerns and future needs. Marine Pollution Bulletin 64: 2630–2638.
- ↑ Strong, J.A., Clements, A., Lillis, H., Galparsoro, I., Bildstein, T., Pesch, R. and Birchenough, S. 2019. A review of the influence of marine habitat classification schemes on mapping studies: inherent assumptions, influence on end products, and suggestions for future developments. ICES Journal of Marine Science 76: 10–22.
