Biology week 8 Discussion 2 PDF

Preview

Summary

weekly homework...

Description

1.

Ecological succession - include what it is and the difference between primary and secondary Succession may be initiated either by formation of new habitat (landslide or lava flow) or disturbance of already existing habitat (fires, land clearance). There are three recognized stages to ecological succession. Each covers a gradual process of change and development. They do not have hard and defined boundaries, and it is possibly for an ecological system to be in both stages at once during the transition period from one to another. The 3 stages of ecological succession are:

1. Primary – This is when an ecological community first enters into a new form of habitat that it has not been present in before. A good example of this would be the habitat created when granite is removed in a quarry. The rock face that is left behind is altered and becomes a new habitat. The environment that then grows within that habitat is considered to be in its primary stage.

2. Secondary – The secondary succession stage occurs after a habitat has been established, but it is then disturbed or changed in some fashion and a new community moves in. To use the example from before – let us say that a primary stage develops on the face of a newly quarried granite cliff. That habitat grows undisturbed, until there is a forest fire that then burns and changes a portion of the habitat that has been growing on the rock face. That ecological habitat has now entered its secondary stage.

3. Climax – the climax stage is the last stage of an ecosystem. It is when the ecosystem has become balanced and there is little risk of an interfering event or change to mutate the environment. Several rainforests and deserts qualify as being in the climax stage. What is tricky about a climax stage is that given human development, any ecosystem that is in the climax stage now holds the risk of being destroyed and going backward in the stages.

2. Limiting factors - what are they and provide two specific examples Limiting factors hinder the population of an organism from flourishing. A densitydependent factor depends on the number of organisms living in a particular area, while a density-independent factor affects all organisms regardless of their population size. A change in a limiting factor, such as the sudden abundance of essential nutrients, may result to an increased population. Nature, however, tends to balance population sizes of various flora and fauna through the predator and prey relationship. Examples of limiting factors include competition, parasitism, predation, disease, abnormal weather patterns, natural calamities, seasonal cycles and human activities.

ReferencesW., R. (2015, January 02). Types and Stages of Ecological Succession - Conserve Energy Future. Retrieved December 07, 2016, from http://www.conserve-energy-future.com/types-and-stagesof-ecological-succession.php...