Topic 4.6 - Biodiversity Within A Community Flashcards
What is biodiversity? (2)
1) Variety of living organisms
2) Can relate to a range of habitats, from a small local habitat to the Earth
What is a community?
All populations of different species that live in an area
What is species richness?
The number of different species in a community
What does an index of diversity do? (2)
Describes the relationship between:
1) The number of species in a community (species richness)
2) The number of individuals in each species (population size)
Suggest why index of diversity is more useful than species richness (2)
1) Also takes into account the number of individuals in each species
2) So takes into account that some species may be present in small or high numbers
Describe how index of diversity values can be interpreted (2)
1) High -> many species present and species evenly represented
2) Low -> habitat dominated by one / a few species
What farming techniques can be used to reduce biodiversity? (4)
1) Removal of woodland and hedgerows
2) Monoculture (growing one type of crop)
3) Use of herbicides to kill weeds
4) Use of pesticides to kill pests
How does removal of woodland and hedgerows reduce biodiversity? (3)
1) Reduces variety of plant species
2) So fewer habitats and niches
3) And less variety of food sources
How does monoculture reduce biodiversity? (3)
1) Reduces variety of plant species
2) So fewer habitats and niches
3) And less variety of food sources
How does use of herbicides to kill weeds reduce biodiversity? (3)
1) Reduces variety of plant species
2) So fewer habitats and niches
3) And less variety of food sources
How does use of pesticides to kill pests reduce biodiversity? (1)
Predator population of pest decreases
Explain the balance between conservation and farming (3)
1) Conservation required t increase biodiversity
2) But when implemented on farms, yields can be reduced, reducing profit / income for farmers
- E.g. by reducing land area for crop growth, increasing competition, increasing pest population
3) To offset loss, financial incentives / grants are offered
Give examples of how biodiversity can be increased in area of agriculture (4)
1) Reintroduction of field margins and hedgerows
2) Reduce use of pesticides
3) Growing different crops in the same area
4) Using crop rotation of nitrogen fixing crops instead of fertilisers
