B6 Biodiversity Flashcards
Explain why destroying heathland to grow wheat would decrease animal biodiversity.
Reduction in the number of plant species
Less VARIETY of food sources
Greater competition for resources
Fewer habitats
What information is needed to calculate index of diversity for a community?
Total number of species present
Total number of each species
What is species richness?
The number of different species in a particular area at a given time
What is biodiversity?
The variety of living organisms in an area
Which is a better indicator of biodiversity - index of diversity or species richness?
Index of diversity
Give 3 ways in which human activity can reduce biodiversity
Removing trees
Remove hedgerows
Use pesticides
Use herbicides
Monoculture
What is a species?
A group of similar organisms that can reproduce and produce fertile offspring
How is the index of diversity calculated?
Σn(n-1)
where N = total number of organisms of all species and n = total number of organisms of each species.
Name the metal frame used when sampling an ecosystem
Quadrat
How can a random sample be achieved?
Place tape measures perpendicular to each other (to make the axes of a graph)
Use a random number generator to produce coordinates
Use the coordinates to place the quadrat down
What is sampling?
Selecting a group of individuals to measure that will represent the whole target population
Why is it important to sample randomly?
Prevent bias
