studying biodiversity Flashcards
What is biodiversity?
Biodiversity is the variety of living organisms in an area.
What is a species?
A species is a group of similar organisms that can reproduce to give fertile offspring.
What is a habitat?
A habitat is the area inhabited by a species, including physical factors like soil and temperature, and living (biotic) factors like food availability and predators.
What is habitat diversity?
Habitat diversity is the number of different habitats in an area. Examples include sand dunes, woodlands, meadows, and streams.
What is species diversity?
Species diversity refers to the number of different species (species richness) and the abundance of each species (species evenness) in an area.
What is genetic diversity?
Genetic diversity is the variation of alleles within a species, such as the variation in breeds within the dog species.
What is the purpose of sampling in biodiversity studies?
Sampling is used to estimate the total number of individuals or species in a habitat without counting every organism, which would be too time-consuming.
What is a quadrat?
A quadrat is a frame used to sample plants by placing it on the ground in a study area.
What is a sweep net?
A sweep net is a net on a pole used for sampling flying insects.
What is a pitfall trap?
A pitfall trap is a small pit used to sample ground insects, where they fall in and can’t get out.
What is the correct sampling technique for aquatic animals?
A net is used to sample aquatic animals.
What should be done when sampling different habitats for comparison?
Always use the same sampling technique when sampling different habitats for consistency.
How can bias be avoided in sampling?
To avoid bias, samples should be random. For example, by dividing a field into a grid and using a random number generator to select coordinates.
What are the types of non-random sampling?
The three types of non-random sampling are systematic, opportunistic, and stratified.
What is systematic sampling?
Systematic sampling involves taking samples at fixed intervals, often along a line, such as placing quadrats along a transect.
What is opportunistic sampling?
Opportunistic sampling involves the investigator choosing samples, though it may introduce bias.
What is stratified sampling?
Stratified sampling involves identifying different areas in a habitat and sampling them separately in proportion to their part of the habitat.
What is species richness?
Species richness is the number of different species in an area. The higher the number of species, the greater the species richness.
How is species richness measured?
Species richness is measured by taking random samples of a habitat and counting the number of different species.
What is species evenness?
Species evenness is a measure of the relative abundance of each species in an area. The more similar the population size of each species, the greater the species evenness.
How is species evenness measured?
Species evenness is measured by taking random samples of a habitat and counting the number of individuals of each species.
What is the relationship between species richness, species evenness, and biodiversity?
The greater the species richness and species evenness in an area, the higher the biodiversity.
How does Simpson’s Index of Diversity work?
Simpson’s Index of Diversity takes into account both species richness and species evenness. It provides a value between 0 and 1, where values closer to 1 indicate more diverse habitats.
How is Simpson’s Index of Diversity calculated?
Simpson’s Index of Diversity is calculated using the formula: D = 1 - Σ(n/N)², where n is the number of individuals of one species, and N is the total number of organisms of all species.
What does a higher Simpson’s Index of Diversity indicate?
A higher Simpson’s Index of Diversity indicates greater species diversity, with higher species richness and evenness.
What does the example field calculation show about the index of diversity?
In the example field with 3 red species, 5 white species, and 3 blue species, the index of diversity is 0.64, indicating a fairly high level of diversity.
How do you calculate the (n/N)² term for Simpson’s Index of Diversity?
For each species, you calculate (n/N)², where n is the number of individuals of that species and N is the total number of organisms of all species, then add them all together.
