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Lecture -8:
Ecological Succession
ENV 107: Introduction to Environmental Science
Dr. A.K.M. Saiful Islam
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
Case Study: Restoring Abandoned
Mine Lands in Great Britain
† In Great Britain, approx. 55,000 ha have been
damaged by mining.
† Recently, in one damaged area (British Peak
District National park) programs have been initiated
to restore these damaged land. First attempt to
restore this area used a modern agricultural
approach: heavy application of fertilizers and
planting of fast growing agriculture grasses. These
grasses green on the good soil of a level firm field.
† But after a short period of growth, the grasses
died!
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
Lesson learned
† On the poor soil, leached of its nutrients and lacking
organic matter, erosion continued and the fertilizers
that had been added were soon leached away by
water runoff.
† Ecological succession, the natural process of
establishment or reestablishment of an ecosystem.
† Instead of planting fast growing but vulnerable
agricultural grasses, ecologist planted slow-growing
native grasses that were known to be adapted to
minerally deficient soils and to the harsh conditions
that exist in cleared areas.
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
Ecological Succession
† Recovery of ecosystem occurs naturally through a
process called ecological succession.
† The natural recovery can occur if the damage is not
too great. Sometimes the rate of recovery is long in
comparison to human desired.
† The disturbance of nature not always usually by
humans. Natural disturbances included: storms, fires
have always been a part of the environment.
† There have been 2 kinds of succession:
„ Primary succession: is initial establishment and
development of an ecosystem.
„ Secondary succession: is reestablishment of an
ecosystem.
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
Examples of Primary succession
†
Forests that develop on new lava flows. Ferns are among the
first plants to reestablish after a new volcanic flow.
(a) Re-vegetation on new
lava flows on Hawaii.
(b) Re-vegetation of the land at the
retreating edge of a New Zealand glacier
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
Examples of Secondary
Succession
† A forest that developed on an abandon pasture or one
grows after a hurricane, flood or fire.
(a) Poconos pasture abandoned filed
(c) Mature forests developed
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
Stages of Succession
† Early successional species: In
forest areas, plants that are rapid
growing and short lived
† Late successional species: Plant
species that dominate later stages of
succession tend to be slower growing
and longer lived. These plants do
comparatively
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
Graph of changes in biomass and
diversity with succession
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
Graph of changes in biomass and
diversity with succession (Contd..)
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
Patterns of interaction
† There are at least three patterns of
interactions among earlier and later species
in succession.
„ 1. Facilitation
„ 2. Interference
„ 3. Life History Differences
† There is actually a fourth possibility:
succession never occurs or chronic
patchiness.
„ 4. Chronic Patchiness
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
1. Facilitations
† One species can prepare the way for the next
(and many even be necessary for the occurrence
of the next).
Pine provide shade and act as “nurse trees” for oak
Pines do well in openings. If there is no pine few or
no oaks will grow. The pine facilitate the entrance of oak
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
2. Interference
† Early successional species may in some way prevent
the entrance of later successional species.
Some grasses that grows in open areas form dense
Mats that prevent seeds of trees from reaching the soil
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
3. Life History Differences
† One species may not affect the time of entrance of
another; two species may appear at different times
during succession.
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
4. Chronic patchiness
† Succession
never occurs
and the species
that enters first
remains until
the next
disturbance.
The null condition, neither positive nor
negative interactions
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
Some special cases of Ecological
Succession
†
†
†
†
1.
2.
3.
4.
Succession among the ocean tides
Wetland succession
Bog Succession
Sand Dune Succession
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
1. Succession among the ocean
tides
† In the ocean, succession occurs where is relation
constancy of the environment such as between the
high and low tidemarks along a rocky shore or in a
coral reef.
† Where the ocean environment is constantly changing,
succession does not appear to occur.
† For example, there is no perceptible succession in the
middle of the ocean, where open ocean waters are
continually stirred by winds, waves, and currents.
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
2. Wetland succession
† From a geologic point of view, a pond is a temporary
feature of a landscape, eventually filling in with
sediments.
† Ponds are common in areas subject to large-scale
geological disturbances, such as glaciation, that shift
the drainage patterns of streams and create
depressions and dams.
† This is why Minnesota, which lies within the heavily
glaciated area of North America, is called the Land of
10,000 lakes.
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
3. Bog Succession
† A bog is a body of water with acid waters
and little if any surface out-flow, so that the
waters have little current.
† Often, a bog has sphagnum moss and inlets
but no surface out-lets.
† Succession in a bog is a process that begins
with open water and ends with a forest .
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
Bog
Succession
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
4. Sand Dune Succession
† Plant succession on sand dunes along beaches is a
worldwide phenomenon, important along the shores
of Great Lakes in North America, in cape Cod,
Massachusetts, where Henry David Thoreau observed
it in the nine-teeth century, along the coasts of
Australia, as well as in the famous Donana National
Park in southern Shores of Spain.
† Dunes along the shores of Lake Michigan were among
the first sites where succession was studied early in
the twentieth century.
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
Dune succession on the shore of Lake Michigan
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
Succession and Chemical Cycling
† On the land, there is generally an
increase in the storage of chemical
elements (Nitrogen, phosphorus, calcium
essential for plant growth) during the
progression from the earliest stages of
succession to middle or late succession.
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
Change in Chemical Cycling during
Disturbance
† When an ecosystem is disturbed by
fire, storms, or human actions,
changes occur in chemical cycling.
† For example, when a forest is burned,
complex organic compounds such as
wood are converted to smaller
inorganic compounds.
ENV 107:Introduction to Environmental Science © Dr. Akm Saiful Islam
How can be Evaluate Constructed
Ecosystem
† 1. Establishment of tide channels with
sufficient fish to serve as food for the
California least tern.
† 2. Establishment of a stable or increasing
population of salt-marsh bird’s beak for
three years.
† 3. Establishment of habitat for the lightfooted successful foraging and nesting of at
least two breeding pairs.