How much do you know about ecological succession?

Ecological Succession: A Summary

• Ecological succession is the process of change in the species structure of an ecological community over time.

• Bacteria plays a crucial role in the cycling of nutrients such as carbon, nitrogen, and sulfur.

• Succession begins with a few pioneering plants and animals and develops through increasing complexity until it becomes stable or self-perpetuating as a climax community.

• Succession may be initiated by the formation of new, unoccupied habitats or by some form of disturbance of a community.

• Primary succession occurs when colonization of an area that has not been previously occupied by an ecological community, while secondary succession follows severe disturbance or removal of a preexisting community that has remnants of the previous ecosystem.

• Succession was first documented in the Indiana Dunes of Northwest Indiana and remains an important ecological topic of study.

• Theories of succession were dominated by Frederic Clements, who held that seres were highly predictable and deterministic, and Henry Gleason, who suggested a much greater role of chance factors.

• The trajectory of successional change can be influenced by site conditions, perturbations, species interactions, and stochastic factors.

• Communities in early succession will be dominated by fast-growing, well-dispersed species, while later succession tends to be dominated by more competitive species.

• The development of ecosystem attributes, such as soil properties and nutrient cycles, are both influenced by community properties and, in turn, influence further successional development.

• Succession was formerly seen as having a stable end-stage called the climax, but this idea has been largely abandoned by modern ecologists in favor of nonequilibrium ideas of ecosystems dynamics.

• Changes in animal life also occur with changing communities and include invertebrates such as slugs, snails, worms, millipedes, centipedes, ants, and vertebrates such as squirrels, foxes, mice, moles, snakes, various birds, salamanders, and frogs.Microbial Succession: Understanding the Process of Ecological Succession in Bacteria

• Microbial succession occurs in newly available habitats and disturbed communities.

• Changes in pH in a habitat could provide ideal conditions for a new species to inhabit the area.

• Microbial communities may also change due to products secreted by the bacteria present.

• Early colonization is mostly influenced by stochasticity while secondary succession of these bacterial communities was more strongly influenced by deterministic factors.

• The final or stable community in a sere is the climax community or climatic vegetation.

• The climax community is self-perpetuating and in equilibrium with the physical habitat.

• There is no net annual accumulation of organic matter in a climax community.

• The annual production and use of energy is balanced in such a community.

• Forests are subject to the species succession process.

• Pioneer species produce great quantities of seed that are disseminated by the wind, and therefore can colonize big empty extensions.

• Shade-tolerant species replace pioneer species when they die.

• Between the two extremes of light and shade, there is a gradient, and there are species that may act as pioneer or tolerant, depending on the circumstances.