Types of Ecological Succession

The types of ecological succession are discussed below:

Primary Succession

Primary succession is a gradual process of change by which a barren area is transformed into a thriving ecosystem. This types of ecological succession starts in places with no plants or animals, like bare land or new volcanic rocks. Over time, microorganisms break down these rocks and create soil in a process called soil erosion.

Then, plants start to grow in the soil. It takes several hundred to 1,000 years for a full community of plants and animals to develop, depending on the area and climate. These plants support different animals, and the ecosystem evolves from simple to more complex. If the ecosystem is disturbed, like by a fire or human activity, secondary succession begin s.

Secondary Succession

Secondary ecological succession occurs in areas where an existing ecosystem has been disturbed, but not completely destroyed. Examples of disturbances include forest fires, floods, landslides, or human activities like farming or logging. Unlike primary succession, secondary succession starts with some remaining and left over fertile soil and organisms (seeds, spores, etc.) from the previous community. This allows for faster recolonization by plants and animals.

Process of Recolonization

The process of recolonization in secondary ecological succession involves:

• Following the disturbance, small, fast-growing plants like weeds and grasses are the first to establish themselves. They benefit from the increased sunlight penetration and readily available nutrients.
• Over time, these pioneer species are gradually replaced by larger plants and shrubs, as the environment becomes more shaded and soil conditions change.
• Through continued succession, the ecosystem progresses towards a stable climax community. This is a self-sustaining ecosystem characteristic of the region’s climate and geography. The climax community represents a mature stage with a complex web of plant and animal life.

Cyclic Succession

Cyclic succession is a pattern of ecological change where the community of organisms in an ecosystem undergoes repeated cycles of growth and decline. Unlike linear succession, which moves towards a stable climax community, cyclic succession involves periodic fluctuations in species composition and environmental conditions. This phenomenon is often observed in ecosystems with recurring disturbances such as seasonal changes, periodic flooding, or regular wildfires.

Each cycle of disturbance starts a sequence of ecological changes with different species dominating at different stages of the cycle. For example, in a freshwater pond, algae may flourish in the summer, followed by a bloom of aquatic plants in the fall, and then a decline in vegetation during the winter.

Seral Community

In ecological succession, a seral community (or sere) is a transitional stage that represents the developing ecosystem at a particular point in time. These communities change and evolve as succession progresses towards a stable climax community. Seres reflect the movement of ecological communities through various stages, from pioneer species to the climax community.

Types of Seres

The various types of seres are:

• Xerosere succession: Takes place in dry areas like rock lithosere, psammosere, and halosere.
• Hydrosere succession: This type of succession starts in the aquatic habitat and progresses from hydric to mesic conditions.
• Lithosere: This type of ecological succession develops on exposed rock surfaces.
• Psammosere: This type of ecological succession starts on the sand.
• Halosere: The plant succession that starts on salty soil and saline water.
• Senile: This type of succession begins on a dead matter of microorganisms.

Ecological succession is the process by which the structure and composition of a biological community change over time. Each of the ecological succession stages is characterized by different species compositions and environmental conditions.

Understanding ecological succession and its types helps in learning the dynamic nature of ecosystems and the complex relationships between organisms and their environment. In this article, we will cover ecological succession in detail.