Definition: Organic matter in soil which has reached a point of stability, where it will break down no further and might, if conditions do not change, remain essentially as it is for centuries, or millennia.
Definition: An area that is inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions.
Definition: Pioneer halo-nitrophilous short-lived vegetation in strandlines of sandy and shingle beaches of the coasts of the North Atlantic and Arctic Oceans, the Mediterranean and the Black Sea
Definition: Tall-grass perennial swards on mobile coastal dunes of the seaboards of Europe, North America, Greenland, North Africa, Middle East and the Caspian Sea
Definition: Of plant duration, a plant whose life span extends over more than two growing seasons, c.f. annual, biennial, ephemeral, of flowering with respect to architecture, hapaxanthic, monocarpic, pleonanthic
