Rivers are drainage
systems that
transport water
(under the influence
of gravity) from
higher points to
lower points of the
topography
Systems are generally fed by
precipitation, but don't always
drain to oceans - some rivers drain
into lakes. Eg. Lake Eyre
The water flows in
unregulated, or
those without dams
or weirs, responds
directly to
precipitation in the
catchment;
although, there may
be considerable
rainfall without
runoff reaching
rivers
Geomorphic
Functions
River systems
transport
soluble and
insoluble
materials.
Rivers are a part of the
mechanism that moves
and redistributed many of
the products of weathering
that breaks down the
catchments landforms,
and also erodes the river
bed and bank
Eg. Boulders (in
heavy flow),
sand, silt, clay
(in light flow)
The geometry of the river
can become unbalanced
and the course takes a
different path. Landform
features remaining after
this redirection of floe are
referred to as relict
features
Ecological and
Scientific functions
Rivers are described as
linear ecosystems
because many life forms
depend on
life-supporting
materials passing
through their habitat.
Rapid alterations can
upset the balance the
balance and lead to
irreparable river
degradation.
A balanced aquatic ecosystem
will help maintain good water
quality.