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
