biodiversity within a community Flashcards
Define biodiversity
The variety of living organisms in an area
Define habitat
The place where an organism lives
Define community
All the populations of different species in a habitat
Describe biodiversity in areas with lots of different species
Areas with lots of different species are high in biodiversity
Define local biodiversity
The variety of different species living in a small habitat that’s local to you
Define global biodiversity
Variety of species on Earth
Where is biodiversity greatest on the Earth?
Near the equator
Define species richness
A measure of the number of different species in a community
How do you calculate species richness?
Taking random samples of a community and counting the number of different species
What is species richness a measure of
Biodiversity
What does the index of diversity calculate?
Measures biodiversity
What does N stand for in the index of diversity formula
Total number of organisms of all species
What does n stand for in the index of diversity formula
Total number of organisms of one species
The higher the index of diversity the…
more diverse the are is
List all the ways that agricultural practices reduce biodiversity
- Woodland clearance
- Hedgerow removal
- Pesticides
- Herbicides
- Monoculture
What is woodland clearance?
Increases area of farmland by cutting down trees
Explain how woodland clearance decreases biodiversity
- It reduces the number of trees and the number of different tree species
- It destroys habitats so some species lose their shelter and food source
- Species will die or be forced to migrate to another area
What is hedgerow removal?
Increases the area of farmland by turnings lots of small fields into fewer large fields
Explain how hedgerow removal decreases biodiversity
- It reduces the number of trees and the number of different tree species
- It destroys habitats so some species lose their shelter and food source
- Species will die or be forced to migrate to another area
What are pesticides
Chemicals that kill organisms that feed on crops
Explain how pesticides decrease biodiversity
- This kills the pests, so it directly reduces biodiversity
- Any species that feed on the pests will lose a food source so their number can decrease too
What are herbicides
Chemicals that kill unwanted plants
Explain how herbicides decrease biodiversity
Kill unwanted plants and weeds reducing plant diversity and could reduce the number of organisms that feed on the weeds
What is monoculture
When farmers have fields containing only one type of plant
Explain how monoculture decreases biodiversity
A single type of plant reduces biodiversity directly and will support fewer organisms as a habitat or food source
Describe the examples of how conservation schemes try to protect biodiversity
- Giving legal protection to endangered species
- Creating protected areas like sites of special scientific interest that restrict agricultural development
- The environmental stewardship scheme which encourages farmers to conserve biodiversity by replanting hedgerows etc
