Ecotone: Ecotones also appear where one body of water meets another (e.g.,
estuaries and lagoons) or at the boundary between the water and the land (e.g.,
marshes). Freshwater and marine ecotones are characterized by the presence of large
plants that rise from roots attached to the submerged substrate, and thus they occur in
areas where ample light is available at the bottom of the basin to permit growth.
•An ecotone is a zone of junction or a transition area between two
biomes [diverse ecosystems]. It is where two communities meet and
integrate.
•Ecotones also appear where one body of water meets another (e.g., estuaries
and lagoons) or at the boundary between the water and the land (e.g., marshes
)..s
•For e.g. the mangrove forests represent an ecotone between marine
and terrestrial ecosystem. Other examples are grassland (between forest
and desert), estuary (between fresh water and salt water) and river bank
or marsh land (between dry and wet).
•Freshwater and marine ecotones are characterized by the presence of large
plants that rise from roots attached to the submerged substrate, and thus they
occur in areas where ample light is available at the bottom of the basin to permit
growth
Characteristics of Ecotone
•It may be narrow (between grassland and forest) or wide (between forest
and desert).
•As it is a zone of transition, it has conditions intermediate to the adjacent
ecosystems. Hence it is a zone of tension.
•Usually, the number and the population density of the species of an
outgoing community decreases as we move away from community or
ecosystem.
•A well-developed ecotones contain some organisms
•which are entirely different from that of the adjoining communities.
In North America the parasitism of bird nests by brown-headed cowbirds (Molothrus
ater) is particularly frequent in ecotones between mature forests and earlier
successional patches. Cowbirds lay their eggs in the nests of other birds and are active
mainly in early successional patches. Forest birds whose nests are deep within the
interior of mature forests are less likely to be attacked than those within ecotones. The
cutting of mature forests has increased the extent of ecotones, concomitantly increasing
the rate of cowbird parasitism across North America.
Edge Effect – Edge Species
The influence of the two bordering communities on each other is known as the edge
effect.
