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Ellenberg moisture value

Formal name:  plant populations moisture indicator value according to Ellenberg
Abbreviation:  F
Local identifier:  TOP779
Synonym Term:  plant moisture preference
Related Term:  drought tolerance
Definition:  a feature of the plant population (EFO:plant population) or plant species (Mayr:species) describing the occurrence of its individuals along soil moisture gradient from dry shallow-soil rocky slopes to swampy grounds and from shallow to deep water
Formal Unit:  unitless (ordinal)

Comment:  The values are indicators for the ecological behavior of a distinct plant species distributed in Central Europe, i.e. for its occurance under field conditions, including competition of many other plants. The different moisture values can be ordered according to increasing soil moisture as follows: from shallow-soil rocky slopes to swampy grounds (F1, F2, F3, F4, F5, F6, F7, F8, F9), from shallow to deep water (F10, F11, F12)
Reference:  Ellenberg, H., Weber, H. E., Duell, R., Wirth, V., Werner, W., Paulissen, D. (1992): Zeigerwerte der Pflanzen in Mitteleuropa, 2nd edition, Scripta Geobotanica, Vol. 18, Goltze KG, Goettingen