Glossary - Fundamentals of the Physical Environment - page 888

Foreshore That part of a beach lying between the low-water mark and maximum high-
tide mark.
Formation A world vegetation type dominated by plants of similar life form and
identified in a geographically distinct area.
Fossil soil A soil formed in the past under environmental conditions which no longer
exist.
Fourth - stage community A community occupying the fourth stage in a vegetation
succession.
Fractional crystallization Separation of a magma during cooling into distinctive, usually
mineral-specific parts.
Fractionation The separation of a mixture into its component elements and minerals.
Fragipan A dense pan-like subsoil horizon, indurated by physical and/or chemical
processes, and with a high bulk density.
Free - living fixation Fixation of atmospheric nitrogen into organic nitrogen compounds
by soil micro-organisms which live freely in the soil rather than existing in association
or symbiosis with a plant.
Friction strength The portion of rock or soil strength dependent on the frictional contact
between constituent particles.
Frost shattering The fracture of rock mass attributed to internal stress generated by
expansion on freezing, pore water migration to a freezing plane or hydration in the
permafrost environment; it is probable that some form of fatigue is involved over
many freeze-thaw cycles.
Froude number An index of the type of flow in a stream.
Fundamental niche The maximum area, in terms of space, time and function, which a
species would be capable of occupying in the absence of competition from other
species.
Gabbro A basic, coarse-grained igneous rock; the intrusive near equivalent of basalt .
Gamma diversity The total biodiversity of a defined geographical region.
Geochemical cycle The movement of rock minerals which accompanies the rock cycle ,
characterized by aggregation, disaggregation, fractionation , refinement, changes of
state and the formation of new species as rock mass itself is cycled.
Geoecology An integrated discipline which studies interactions between geological,
geomorphic, ecological and meteorological components of the landscape.
Geological process A process usually involving or associated with Earth's near surface
or interior rocks, and distinct from - or combined with - geomorphological process .
Geomorphic Pertaining to Earth's surface landforms and their study.
Geomorphological process A process involved in the formation and alteration of the
landforms at Earth's land surface.
Geophytes A class of plants which reproduce from bulbs, corms, rhizomes or tubers.
Geothermal heat flow The heat loss from Earth's interior to space, measured at an
average Earth surface flux of 82 mW m −2 but locally varying according to the
proximity of hot spots, volcanoes, etc.
Gibber A desert rock surface covered with lag gravels .
Gilbert - type delta A 'classic' fan delta with successive overlapping topset, foreset and
bottomset beds on the prograding surface, advancing front and distal slope
respectively.