9.4 Functions of Riparian Ecotone
Though having characteristics and distinct features, the riparian ecotone delivers an
important role in both the terrestrial and aquatic ecosystems, which remains homogenous across the globe. These ecotones play an important role in physical, biological
and ecological functions (Klapproth and Johnson 2009), adding to the importance of
interactions taking place in this zone between soil, water and biotic communities.
The functions of riparian ecotone are dependent on the land use features comprising
the riparian ecotone. All over the globe, these regions are experiencing the transformation from natural vegetation to agriculture and subsequently to human habitations
(Sharma et al. 2016). However, the role, importance or function of riparian ecotone
is discussed and researched mostly in terms of natural vegetation. Certain basic
functions of riparian areas are as stated below.
9.4.1 Bank Stabilisation
The vegetation cover over soil has already been known to hold the soil, thus playing
the prominent role in the conservation of the top soil. A similar kind of role has been
reported long back during the 1980s for establishing the importance of vegetation
near rivers towards riverbank stabilisation (Omernik et al. 1981; Smith 1992;
Arthington et al. 1997; Townsend and Douglas 2000). Riparian vegetation has
shown to play an important role in protecting the river shorelines from damage
caused to soil during heavy flows such as runoff from upland or downpours (EPA
2010). Riparian vegetation mediates their input by armouring stream banks against
erosion, storing runoff, trapping sediment and transforming nutrients (Omernik et al.
1981; Smith 1992; Osborne and Kovacic 1993; Arthington et al. 1997; Townsend
and Douglas 2000) (Fig. 9.2).
The mechanism by which riparian area does is slowing the flow of water, thus
ensuring that sediments settle out before they reach the water course (Montgomery
et al., 1996). In a naturally vegetated riparian ecotone, floodwater overshoots from
the bank and spreads out the broad floodplain, thus reducing the energy of the water
(https://www.nrcs.usda.gov/). As floodwater flows through a vegetated area, the
plants resist the flow and dissipate the energy, increasing the time available for
water to infiltrate into the soil and be stored for use by plants (https://www.nrcs.usda.
gov/). The roots of the plants increase the riverbank cohesiveness adding a tensile
strength which enables the riverbank soil to resists shear stresses (Castelle and
Johnson 2000). Thus, de-voiding the fluvial system from its natural vegetation can
have adverse effects on the stability of its bank (Fig. 9.2).
206
S. Sharma et al.
Though having characteristics and distinct features, the riparian ecotone delivers an
important role in both the terrestrial and aquatic ecosystems, which remains homogenous across the globe. These ecotones play an important role in physical, biological
and ecological functions (Klapproth and Johnson 2009), adding to the importance of
interactions taking place in this zone between soil, water and biotic communities.
The functions of riparian ecotone are dependent on the land use features comprising
the riparian ecotone. All over the globe, these regions are experiencing the transformation from natural vegetation to agriculture and subsequently to human habitations
(Sharma et al. 2016). However, the role, importance or function of riparian ecotone
is discussed and researched mostly in terms of natural vegetation. Certain basic
functions of riparian areas are as stated below.
9.4.1 Bank Stabilisation
The vegetation cover over soil has already been known to hold the soil, thus playing
the prominent role in the conservation of the top soil. A similar kind of role has been
reported long back during the 1980s for establishing the importance of vegetation
near rivers towards riverbank stabilisation (Omernik et al. 1981; Smith 1992;
Arthington et al. 1997; Townsend and Douglas 2000). Riparian vegetation has
shown to play an important role in protecting the river shorelines from damage
caused to soil during heavy flows such as runoff from upland or downpours (EPA
2010). Riparian vegetation mediates their input by armouring stream banks against
erosion, storing runoff, trapping sediment and transforming nutrients (Omernik et al.
1981; Smith 1992; Osborne and Kovacic 1993; Arthington et al. 1997; Townsend
and Douglas 2000) (Fig. 9.2).
The mechanism by which riparian area does is slowing the flow of water, thus
ensuring that sediments settle out before they reach the water course (Montgomery
et al., 1996). In a naturally vegetated riparian ecotone, floodwater overshoots from
the bank and spreads out the broad floodplain, thus reducing the energy of the water
(https://www.nrcs.usda.gov/). As floodwater flows through a vegetated area, the
plants resist the flow and dissipate the energy, increasing the time available for
water to infiltrate into the soil and be stored for use by plants (https://www.nrcs.usda.
gov/). The roots of the plants increase the riverbank cohesiveness adding a tensile
strength which enables the riverbank soil to resists shear stresses (Castelle and
Johnson 2000). Thus, de-voiding the fluvial system from its natural vegetation can
have adverse effects on the stability of its bank (Fig. 9.2).
206
S. Sharma et al.