Lecture -8: Ecological Successionteacher.buet.ac.bd/akmsaifulislam/env107/lecture-8.pdf · Lecture -8: Ecological Succession ENV 107: Introduction to Environmental Science Dr. A.K.M

Lecture Lecture --8:8:

Ecological SuccessionEcological 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!


Lesson learnedOn 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.


Ecological SuccessionRecovery 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.


Examples of Primary successionForests that develop on new lava flows. Ferns are among the first plants to reestablish after a new volcanic flow.

(b) Re-vegetation of the land at the retreating edge of a New Zealand glacier

(a) Re-vegetation on new lava flows on Hawaii.


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


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


Graph of changes in biomass and diversity with succession


Graph of changes in biomass and diversity with succession (Contd..)


Patterns of interactionThere are at least three patterns of interactions among earlier and later species in succession.

1. Facilitation2. Interference3. Life History Differences

There is actually a fourth possibility: succession never occurs or chronic patchiness.

4. Chronic Patchiness


1. FacilitationsOne 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 oakPines do well in openings. If there is no pine few orno oaks will grow. The pine facilitate the entrance of oak


2. InterferenceEarly 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


3. Life History DifferencesOne species may not affect the time of entrance of another; two species may appear at different times during succession.


4. Chronic patchinessSuccession never occurs and the species that enters first remains until the next disturbance.

The null condition, neither positive nor negative interactions


Some special cases of Ecological Succession

1. Succession among the ocean tides2. Wetland succession3. Bog Succession4. Sand Dune Succession


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.


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.


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 .


Bog Succession



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.


Dune succession on the shore of Lake Michigan


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.


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.


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 light-footed successful foraging and nesting of at least two breeding pairs.

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Lecture -8: Ecological Successionteacher.buet.ac.bd/akmsaifulislam/env107/lecture-8.pdf · Lecture -8: Ecological Succession ENV 107: Introduction to Environmental Science Dr. A.K.M