10.3 Study Guide Flashcards
What is the definition of ecological succession?
The process in which over time a habitat and the species in that habitat change.
What are the definitions of primary and secondary succession?
Primary Succession: The beginning of the creation of an ecosystem/habitat after something big happens (a glacier retreating, new/more land being uncovered, etc).
Secondary Succession: The process of primary succession repeating after another big event (such as a creek flooding, deforestation, etc). The process is faster because there’s already soil and such.
What is the definition for pioneer species?
The first colonizers (lichens, mosses, ferns, and bacteria).
What are the seral stages?
As soil quality and quantity improves, the life forms present in the area undergo a series of changes.
What is a climax community?
A completely formed and matured ecosystem.
What are species evenness and richness?
Species richness: Number of different types of spcies.
Species evenness: Abundance/proportion of species.
Please explain genetic diversity and ecological diversity.
Genetic diversity: Often related to size of population.
Ecological diversity: Range of habitat types, variation within ecosystems.
Please explain the definitions of keystone species and invasive species.
Key stone species: Influential ecological role. Exert important regulating effect on other species. Increases diversity in habitat.
Invasive species: Non-native species. Out-compete native species, lack of predators, parasites, competitors. An exponential growth.
What are important differences between primary and secondary succession?
Primary Succession: Barren rock from beneath a retreating glacier, or due to a volcanic eruption. A thin layer of soil develops. Takes 100-200 years to mature/finish/reach climax community.
Secondary Succession: Establish the climax community. Forest fire. Plants have been destroyed and animals have fled the burned out area. A layer of ash is over the soil. 50-100 years to reach climax community again.
How do keystone species and invasive species affect biodiversity?
Keystone species: Help make sure one species doesn’t overpopulate, and other species don’t go extinct in the area. They help increase diversity in the area.
Invasive species: They aren’t native to the area, and take over. There’s a lack of predators, parasites, competitors, etc. This may cause native species to go extinct in the area and the ecosystem to fall apart.
Please give examples of primary and secondary succession.
Primary Succession: Volcanic eruption, soil starts developing, habitats are built for plants and animals, a forest or other plants and animals become mature and ecosystem establishes.
Secondary Succession: Soil is already developed and the ecosystem is already established, a natural or human-caused disaster happens (ex: forest fire), another climax community is established.
Please calculate the Shannon-Wiener Index value for this community: Species 1 - 84, species 2 - 4, species 3 - 91, species 4 - 34, and species 5 - 43.
84 + 4 + 91 + 34 + 43 = 256.
84/256 = 0.33 x ln(0.33) = -0.37.
4/256 = 0.02 x ln(0.02) = -0.08.
91/256 = 0.36 x ln(0.36) = -0.37.
34/256 = 0.13 x ln(0.13) = -0.27.
43/256 = 0.17 x ln(0.17) = -0.30.
0.37 + 0.08 + 0.37 + 0.27 + 0.30 =
1.39
Please compare and contrast the biodiversity between these values:
Species richness - Community 1: 5, Community 2: 4.
Species evenness: Community 1: 40, 40, 40, 40, 40. Community 2: 5, 5, 175, 5, 5.
Shannon-Wiener Index (H): 1.6 and 0.18.
Species richness: Community 1 has more richness because they have 5 species as to where Community 2 has 4.
Species evenness: Community 1 is completely even (all 40s), but Community 2 is not (all 5s but 1).
Shannon-Wiener Index (H): 1.6 means there’s higher diversity as to where 0.18 means there’s lower diversity.
