11.4 - Calculating biodiversity Flashcards
Why is species diversity often proportional to ecosystem stability?
Ecosystems with higher species diversity are generally more stable, as species can support each other and adapt to environmental changes.
How does pollution affect biodiversity?
Pollution reduces biodiversity by creating harsh conditions, allowing a few species to dominate while others decline or disappear.
Why is monitoring biodiversity important?
Monitoring biodiversity helps conservationists track environmental health and assess the effectiveness of conservation efforts.
What is the simplest way to measure biodiversity?
Counting the number of species present (species richness).
Why is species richness not always the best measure of biodiversity?
It does not account for species evenness, meaning a habitat with a few dominant species may appear diverse when it is not.
What formula is used to calculate Simpson’s Index of Diversity (D)?
D = 1 - ∑(n/N)^2
where:
∑ = sum of (total)
N = the total number of organisms of all species
n = the total number of organisms of a particular species
What does a Simpson’s Diversity Index (D) value tell us?
D = 0 → No biodiversity
D = 1 → Infinite biodiversity
The higher the value, the more diverse the ecosystem.
How does Simpson’s Index of Diversity improve upon species richness?
It accounts for both species richness and species evenness, providing a more accurate measure of biodiversity.
How does the number of species differ in high vs. low biodiversity habitats?
Low Biodiversity = Few
High Biodiversity = Many
How does the environment differ in high vs. low biodiversity habitats?
Low Biodiversity = Stressful/Extreme
High Biodiversity = Benign/Not stressful
How does species adaptation differ in high vs. low biodiversity habitats?
Low Biodiversity = Highly adapted species
High Biodiversity = Generalist species
How do food webs differ in high vs. low biodiversity habitats?
Low Biodiversity = Simple
High Biodiversity = Complex
How does the impact of environmental changes differ in high vs. low biodiversity habitats?
Low Biodiversity = Major effects
High Biodiversity = Small effects
Why is it important to conserve low biodiversity habitats?
Low biodiversity habitats may contain rare, highly adapted species that cannot survive elsewhere, making them important for conservation.
