1.2 - Succession Flashcards
Define ‘succession’.
The process by which plants naturally occupy a site and over time bring about changes in plant and animal communities, and therefore changes in the level of biodiversity.
What are the two types of succession?
- Primary Succession
- Secondary Succession
Define ‘primary succession’.
The establishment of communities on bare ground (no soil), such as lava fields or glaciated landscapes.
Define ‘secondary succession’.
Occurs in an environment that was once inhabited and has become barren, but still contains soil nutrients.
What is a ‘sere’?
A stage of succession.
What is the role of primary colonisers in primary succession?
Pioneers such as lichens break down rock to soil.
Describe the sequence of succession from primary colonisers to climax community.
- Pioneers (lichens)
- Grasses and ferns
- Herbaceous plants
- Shrubs
- Trees/woodland (climax community)
What factors influence succession?
- Climatic factors
- Edaphic factors (related to soil, e.g., moisture, pH, organic matter, nutrient content)
What are edaphic factors?
Factors related to or affected by soil, such as soil moisture, pH, organic matter content, and nutrient content.
What changes occur in the soil during primary succession?
The soil becomes richer and more complex as organic matter is added.
What characterizes a climax community?
- Stable
- Can recover well from disturbances
- Well developed community structure
- Supports high biodiversity
- Produces high biomass
True or False: Primary succession can take over 1000 years.
True
Fill in the blank: A _______ is a stable plant community that arises as a result of human intervention in the natural succession of communities.
[plagioclimax]
What is the common climax community in the UK?
Deciduous woodland.
What is the significance of the seed bank in secondary succession?
It allows for rapid regrowth of herbaceous species after vegetation has been removed.
What happens during the phase of grasses in primary succession?
Grasses and ferns take root, outcompeting primary colonisers for light, water, nutrients, and space.
What is a ‘plagioclimax’ community?
A stable plant community influenced long-term by human activities.
List some examples of human interventions that can create a plagioclimax.
- Mowing the grass
- Weeding
- Grazing by livestock
- Muirburn
What is the role of lichens in primary succession?
Lichens break down rock to form soil.
What is the first life stage in primary succession?
Pioneers or primary colonisers, usually lichens.
Describe the characteristics of a mature woodland.
Contains a rich mix of plant and animal species, with varying ages and sizes.
What is the importance of competition during succession?
Competition between species for resources leads to changes in community structure.
What does the process of succession ultimately lead to?
A climax community where the vegetation is in equilibrium with the environment.
