Biodiversity - 4 Flashcards
How can biodiversity be measured
Habitat Biodiversity
Species Diversity
Genetic Diversity
What is habitat diversity
The number of different habitats in an area
What is species diversity
The number of species in an area
OR
The abundance of each species in an area
What is genetic diversity
The variation of alleles within a species
Describe a method for random sampling with a quadrat
Divide the area into a large grid eg 10m x 10m & ensure the area is chosen as randomly as possible.
Use a random number generator to generate the
co-ordinates of at least 10 samples.
Take the quadrat and place on the co-ordinates.
Measure the abundance or % cover of plant species in
that quadrat.
Repeat for the other quadrats
Describe how a pitfall trap works
Dig a hole.
Place cup in the hole, level with the surface.
Make a raised cover in case it rains or there are
scavengers.
Leave 24 hours.
Count and identify invertebrates (use a key).
Make at least 5 traps placed randomly.
What does the Simpsons biodiversity index measure
Measures the diversity of a habitat, taking into
account species richness & evenness.
What factors affect biodiversity
Human population growth
Agriculture
Climate change
What is biodiversity
The variety of living organisms. It can be measured in terms of species diversity , habitat diversity and genetic diversity
What is species richness
The number of species in an area
What is species evenness
Whether species have similar numbers
What is the Simpsons diversity index
A measurement of the total number of organisms compared to the total number of organisms of each species
What does the diversity index mean
A high index means several species are equally abundant, where as a low index means one or two species dominate over others
How can we assess genetic diversity
Proportion of polymorphic gene loci = number if polymorphic gene loci/ total number of loci
Give 3 reasons to maintain biodiversity
Ecological
Economic
Aesthetic
