Biodiversity Indices 3&4 Week 2 Flashcards
A species is?
A group consisting of all collected populations of morphologically & genetically similar organisms that can interbreed with one another.
A population is?
Consists of all individuals of the same species within an area that show a reproductive isolation from other populations
A biological community is?
interacting populations in an area at a certain time.
Whats the diversity-stability hypothesis?
Relationship between DIVERSITY and community/ecosystem STABILITY which results in RESILIENCE.
What are the 4 levels of organisation?
- Species
- Ecosystem
- Population
- Community
What is species richness?
The measure of the no. of species that occur within a particular taxonomic level in a given region.
What is species diversity?
The no. of different species and the relative abundance of each species in a community.
What are the factors that can change local species diversity?
- Speciation
- Extinction
- Emigration
- Immigration
What does diversity represent?
The health of an ecosystem
What is latitudinal diversity gradient? (LDG)
The increase in species richness towards the tropics in marine, freshwater and terrestrial species.
What are 1&2 of the trends of elevation diversity gradient. (EDG)
Decrease in richness with increasing elevation
What are 3&4 of the trends of elevational diversity gradient (EDG)
Decreasing with or without a mid-elevation peak.
What are the features of Latitudinal Diversity Gradient?
- Cllimatic
- Spatial
- Historical
- Evolutionary factors
What are the features of Elevational Diversity Gradient
- Climatic
- Spatial
- Biological processes
- Evolutionary factors
What are the measures of biodiversity
- Alpha diversity within habitat
- Beta diversity
- Gamma diversity
What can we measure in biodiversity
- Species richness
- Abundance
- Diversity (relationship between richness & abundance)
What can we measure in biodiversity
- Species richness
- Abundance
- Diversity (relationship between richness & abundance)
What factors are related to variability in patterns of small scale species richness among communities.
- Geographic factors
- Biotic factors
- Abiotic environmental factors
What is beta diversity
No. of distinct compositional units in the region
no. of different communities in a region
What are species richness counts highly sensitive to?
The no. of individuals sampled.
- No. samples
- Size of samples
- Special arrangement of samples.
What does S represent in Menhinick’s index
No. of different species in the sample
What does N represent in Menhinick’s index
Total no. of individuals in the sample.
