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Wetland Ecosystem Development. Chapter 7. What is Succession. Wetland succession is wetland development. This chapter looks at how wetlands have been and are developed. The earliest definitions of succession involve three concepts:
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Wetland Ecosystem Development Chapter 7
What is Succession • Wetland succession is wetland development. This chapter looks at how wetlands have been and are developed. • The earliest definitions of succession involve three concepts: • 1) vegetation occurs in recognizable and characteristic communities. • 2) such changes are brought about by biota. • 3) changes are linear and directed towards a mature, stable ecosystem. The following slide illustrates such an example.
Autogenic vs. Allogenic Succession • Autogenic succession occurs as a result of biotic factors. The accumulation of organic matter such as dead plants can cause change in an ecosystem. • Allogenicsucession does not involve plants (abiotic). It can be caused by volcanos, flooding or the cessation of it, human interference, etc.
Limitations to Autogenic Succession • Usually decaying plant matter occurs as some kind of peat. This peat accumulates on anoxic soil. At least it is anaerobic. • So in the presence of oxygen (like peat no longer submerged), the dead matter will start to decay. • Natural climatic change
Ecosystem Attributes • Wetland ecosystem development work largely attributed to the work of Eugene Odum. • Says that the type of species in each stage of development less important than its production in relation to its biomass (its mass). • Immature species are more productive in relation to their biomass than mature species. • However, mature species tend to have a higher quality (higher quantity of flowers, fruits, etc.)
Other characteristics of mature ecosystems • Dendrite-based food chains • Organisms form niches (specialties) • Lifecycles longer and more complex • Higher organism diversity • Nutrients and energy more likely to be recycled within the system.
Wetland Ecological Characteristics • They have both immature and mature properties. • Production tends to be high like an immature ecosystem, but the food chain is complex and dendrite-based. • Wide Variety of Mineral Cycles • Can be a contained system where water does not leave or an open system like a tidal march which is flooded daily. • Lifecycles short but complex • Short lifecycles are characteristic of immature ecosystems, but the organisms are well adapted to the particular environment.
Ecosystem Engineers • Organisms who have a dramatic effect on an ecosystem. • Examples include beavers and nutria. • They have the ability to reverse wetland succession. • Physical forces such as tides can also set back wetland succession.
