Essay On Ecological Succession

Community structures and functions are constantly changing. Organisms die and replaced over time. The gradual process by which ecosystems change and develop over time is called ecological succession. Succession is usually defined as ‘a continuous, unidirectional, sequential change in the species composition of a natural community’ (Mackenzie, Ball & Virdee, 2001). Succession occurs because the environmental conditions in a particular area change over time. Each species is adapted to compete against other species under a very specific set of environmental conditions. If these conditions were to change, the existing species will be replaced by a new set of species that are better adapted to the new conditions.
Ecologists recognize two main types of succession, primary succession and secondary succession. Primary succession occurs on an area that is originally completely empty of life. For example, primary succession can develop on newly formed volcanic islands, bare rocks exposed by an avalanche, sand dunes, ponds and lakes. (Chenn, 1999) Secondary succession is far more common and it occurs on areas where it had been previously supported by a type of community but has then been destroyed. A few examples are, a forest that has been destroyed by a wildfire; plants are destroyed due to human cultivation and other plants may have been trampled to form pathways. Over a period of time, no living organisms may have lived in that area. However, certain types of plants begin to reappear. If the disturbance stops, the area will begin a secondary succession, changes in the vegetation will lead back to a climax community. (Browning, 1998)
The aim of this experiment is to have an understanding of the rates of succession at Shingle Ridge, Slapto...

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...s that the future species have a lower tolerance level for resources. By having low resources needed to sustain those that arrived earlier, the future species are then able to displace them. An example of this is when an oak tree grows tall enough to overshadow shorter plants, such as shrubs. According to the inhibition hypothesis, all species resist invasion of competitors and are only displaced by death or damage from factors other than competition.
It was predicted that there was little to no life in the area near the sea due to the harsh living conditions next to the water. So the further the distance the species are away from the sea and towards the back of the sand dunes, the higher the amount of species and diversity. This is due to the less disturbance and less harsh conditions such as a lower salt content, and better nitrogen deposition for plants to grow.