Ecological Succession

Ecological succession refers to a dynamic process that brings about changes in the species composition of an ecosystem over time. The process of ecological succession involves both living organisms and the physical environment, leading to the establishment of diverse and complex communities. This article explores the concepts of primary and secondary succession, as well as cyclic succession while delving into different types of seres and their significance in ecological development.

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Table of Content

• Ecological Succession
• Causes of Ecological Succession
• Primary Ecological Succession
• Secondary Ecological Succession
• Cyclic Ecological Succession
• Seral community
• Types of Seres
• Conclusion
• Frequently Asked Questions (FAQs)

What is Ecological Succession?

• Definition: Ecological succession is a process of change in the species composition of an ecosystem over time.
• Both the biotic and abiotic components are involved in this change.
• This change is brought about both by the activities of the communities as well as by the physical environment in that particular area.
• The physical environment often influences the nature, direction, rate and optimal limit of
• Changes.
• Types of ecological succession: primary succession and secondary succession.

Causes of Ecological Succession

Initial Causes

The factors that contribute to the destruction of existing habitats are the primary causes of ecological succession. These causes can be attributed to the following factors:

• Climatic Factors: wind, deposits, erosion, and fire.
• Biotic Factors: Various activities carried out by organisms.

Continuing Causes:

The factors that lead to changes in population and the shifting characteristics of an area are the continuing causes of ecological succession. These factors include:

• Migration for Safety
• Migration due to Industrialization and Urbanization
• Reactionary Response to Local Problems
• Competition among species

Stabilizing Cause:

Causes that promote stability within communities. These factors include:

• Land Fertility
• Climatic Conditions
• Availability of Minerals

Primary Ecological Succession

• Primary succession occurs in areas where there is no soil or life, such as rocks outcrop, newly formed deltas and sand dunes, emerging volcano islands and lava flows as well as glacial moraines (muddy areas exposed by a retreating glacier).
• Pioneer species, such as lichens and mosses, are the first to colonize the area and create soil.
  • Pioneer species: the plants that invade first bare land, where the soil is initially absent.
• Over time, other species, such as grasses and shrubs, replace the pioneer species, leading to a more complex ecosystem.

• Pioneer community: The community that initially inhabits a bare area is called the pioneer community.
• The pioneer community after some time gets replaced by another community with a different species combination.
  • This second community gets replaced by a third community.
• This process continues sequence-wise in which a community is replaced previously by another community.
• Climax community: the terminal (final) stage of succession forms this.
  • A climax community is stable, mature, more complex and long-lasting.
  • A climax community as long as it is undisturbed, remains relatively stable in dynamic equilibrium with the prevailing climate and habitat factors.

Secondary Ecological Succession

• Secondary succession is a type of ecological succession that occurs in areas where there is already soil and life, such as after a forest fire or human disturbance.
• The process is similar to primary succession, but the pioneer species are different.
• Secondary succession occurs when the starting point is bare soil that already exists.
• The pioneer species in secondary succession are often fast-growing plants and often come from pre-existing groups of organisms in the area.
• The process of secondary succession is faster than primary succession because the soil and some nutrients are already present.
• Secondary succession is important for the restoration of ecosystems and the establishment of biodiversity in an area.
• Examples:
  • Regrowth of a forest after a fire,
  • Regrowth of a field after abandonment, and
  • Regrowth of a wetland after draining.

Cyclic Ecological Succession

• Cyclic succession is a pattern of vegetation change in which a small number of species tend to replace each other over time in the absence of large-scale disturbance.
• The cyclic model of succession was proposed in 1947 by British ecologist Alexander Watt.
• It is one of several kinds of ecological succession, a concept in community ecology.
• Cyclic succession is different from the primary and secondary succession because it is not initiated by wholesale exogenous disturbances or long-term physical changes in the environment.
• Cyclic processes can also be observed in cases of secondary succession in which regular disturbances such as insect outbreaks occur.

Seral community

• A seral community is an intermediate stage found in ecological succession in an ecosystem advancing towards its climax community.
• It is the name given to each group of plants within the succession.

Types of Seres in ecological succession

• Xerarch: It refers to an ecological succession that originates in a dry habitat.
• Hydrarch: It refers to an ecological succession that originates in a water environment.
• Lithosere: It is a plant succession that begins life on a newly exposed rock surface.
• Psammosere: It is a seral community, an ecological succession that began life on newly exposed coastal sand.
• Halosere: it is a succession in a saline environment.
• Senile: It is defined as the point where a plant succession does not develop any further because it has reached equilibrium with the climate.
• Eosere: It is the succession of microbes on dead organisms.

Conclusion

Ecological succession is a fascinating process that unveils the ever-changing dynamics of ecosystems over time. From the initial colonization of pioneer species to the development of complex communities and the establishment of a stable climax community, each stage plays a vital role during ecological succession in shaping biodiversity and maintaining ecological balance. Whether through primary or secondary succession, or even cyclic patterns, the interconnectedness of biotic and abiotic factors drives the remarkable journey of ecological succession, highlighting the resilience and adaptability of nature’s intricate web of life

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FAQs (Frequently Asked Questions)