-Describe succession along coastal sand dunes, bogs and old fields. Be sure to b
ID: 457 • Letter: #
Question
-Describe succession along coastal sand dunes, bogs and old fields. Be sure to both distinguish between primary and secondary succession and name specific plant species in each environment.
-Define the three mechanisms of ecological succession and give examples of two of those mechanisms.
Describe succession along coastal sand dunes, bogs and old fields. Be sure to both distinguish between primary and secondary succession and name specific plant species in each environment. Define the three mechanisms of ecological succession and give examples of two of those mechanisms.Explanation / Answer
Succession
orderly succession of communities to a climax community (biome)
sequence of communities --> sere
each transitory community --> seral stage
For instance, in Ohio, a simple description of a sere that would develop on an abandoned field might be:
grass -> shrubs -> trees -> oak-hickory forest
In this sere, the grass is the pioneer community and the oak-hickory forest is the climax community. Each step in the sere (grass, shrubs, trees, oak-hickory forest) is individually known as a seral stage. There are two main types of succession:
1. Primary succession
begins with bare rock exposed by geologic activity - volcanism, glaciers, etc.
example sere: rock -> lichen -> moss -> grass -> shrub -> trees -> oak hickory forest
2. Secondary succession
begins on soil from which previous community has been removed (by fire, agriculture, etc.)
old field succession
example sere: grass -> shrub -> trees -> oak hickory forest
secondary succession can proceed much faster because the soil has been prepared by the previous community
MECHANISMS OF SUCCESSION
Nudation
The general process of ecological succession starts with Nudation, which is the development of a bare site without any life form. The three types of causes of nudation are topographic, climatic, or biotic. It is topographic if it is due to soil erosion by gravity, wind or water, with examples of these being soil erosion, landslide, and earthquakes. The cause of nudation is climatic when dry periods, glaciers, storm and hail and the like destroy the previously existing community. It is biotic when human activity is involved and man is responsible for the destruction; also, epidemics caused by bacteria, etc destroy the whole population. Whatever the cause of nudation, soon after, a new surface in the area will be exposed.
Invasion
The mechanism that follows nudation is Invasion, the successful establishment of species in a bare area. Invasion usually happens in three steps, namely: migration, ecesis, and aggregation. Migration happens when various migration agents like water and wind make seeds, spores, and/or other propagules of species reach and disperse the bare site. Ecesis, the process of successful establishment of a plant or animal species in a habitat, is the following step after the propagules or seeds successfully adjust with the prevailing condition of the bare site. Colonization may also follow ecesis; it is also the initial growth of the vegetation, or when the seeds or propagules begin to grow a start to reproduce. In Aggregation, the established organisms in the bare area increase in number due to colonization by successive offspring and new migrants. Those plants first to colonize are called pioneers.
Coaction
The next mechanism is Competition and Coaction. As the aggregation of the number of individuals increases, competition arises as a result of natural resistance like the need for the acquisition of nutrition, light and the limited space. The said competition can either be interspecific or intraspecific. The two differ in terms of the species involved. Interspecific competition involves different species competing for the same source, while intraspecific competition involves organisms belonging to the same species competing for the same source. Coaction on the other hand is defined as
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.