Dynamics of lotic and lentic

1. Dynamics of Lotic and
Lentic environment
Tahira Jabeen
Oxbridge college Kasur

2. Dynamics of lotic environment
 In the lotic series, the tiny rivulet gradually deepens,
widens its bed, and cuts back at its head, thus in time
extending its length and increasing its cross section to
that size which justifies the designation of brook.
 This process continues by the same general type of action,
ultimately producing a creek and then finally a river, with
all of the integrating conditions produced in such a
gradual transformation.

3. Dynamics of lotic environment
 Faunas occupying each of the different environments must
accompany these migrations or become adapted to the
gradually altering conditions or they will become extinct.
 These environmental migrations are very slow, in point of time,
and give ample opportunity for the characteristic organisms of
particular environments to make the necessary responses.
 The ultimate fate of any lotic series is the degradation of the
land is the reduction of its bed to base level.

4. Dynamics of Lentic environment
 In the lentic series, natural processes work toward
extinction, mainly by the gradual filling of basins
 Lake –> Pond –> Swamp
 In larger lakes, natural filling takes much longer time,
even many centuries also hence the filling is primarily due
to :
 Wind blown materials such as dust, sand and debris of
various sorts.
 Sediments brought into a lake by inflowing streams and by
incoming run off water as it flows down adjacent land
slopes.

5. Dynamics of Lentic environment
 Wave action, cutting away exposed shores and depositing
eroded material in lake basin.
 Plants, particularly the higher aquatic plants which grow
in shallow water, produce deposits of organic matter.
 Accumulating remains of animal life especially shells.

6.  Not all lakes become extinct by filling alone. Other
process also contributes to this for example an outlet may
cut down its level at the point of exit from a basin, thus
gradually draining the lake.
 These stages in the extinction of standing waters result in
a more or less definite, predictable ‘evolution of
environment in the long run has a profound influence on
the history and fate of lake organisms.