Division 1.2.1 Rivers
United Kingdom
System A
| Fixed typology | Descriptors |
|---|---|
| Ecoregion | Ecoregions shown on map A in Annex XI |
| Type | Altitude typology high> 800 m 200 to 800 m < 200 m Size typology based on catchment area small10 to 100 km2 > 100 to 1 000 km2 > 1 000 to 10 000 km2 > 10 000 km2 Geology
|
System B
| Alternative characterisation | Physical and chemical factors that determine the characteristics of the river or part of the river and hence the biological population structure and composition |
|---|---|
| Obligatory factors | altitude latitude longitude geology size |
| Optional factors | distance from river source energy of flow (function of flow and slope) mean water width mean water depth mean water slope form and shape of main river bed river discharge (flow) category valley shape transport of solids acid neutralising capacity mean substratum composition chloride air temperature range mean air temperature precipitation |