4.6 Biodiversity Flashcards
1
Q
Define genetic diversity
A
The number of different alleles of genes in a population
2
Q
Define species richness
A
The number of different species in a community
3
Q
Describe and explain why the index of diversity is a better measurement than species richness
A
- Index of diverity factors in the population of each species, as well as species richness
- That is useful, as there may be very few or many of one species
4
Q
A
5
Q
What is N in this equation
A
The total number of organisms of all the species
6
Q
What is n in this equation
A
The number of individuals of each species
7
Q
How can you obtian more precise values of the index of diversity
A
- Use random number generator to randomly sample
- Take many more samples (at least 30) to find a mean of the number of each species
8
Q
Points to include when explaining effects of changing an ecosystem
A
- Effect on habitats
- Effect on all species involved
- Effect on food sources
9
Q
How does farming reduce biodiversity
A
- Destruction of hedgerows
- Selective breeding
- Monocultures
- Use of pesticides
- Over-grazing
- Filling in ponds and draining wetlands
10
Q
How is a balance reached between conservation and farming
A
- Compromise on how many hedges removed
- Only use selective breeding in certain areas or on certain species
- Crop rotations
- Biological control instead of pesticides
11
Q
How does plant diversity affect animal diversity
A
- Reduce plant diversity means fewer food sources and habitats
- So animal diversity reduced
12
Q
How to standardise sampling procedure
A
- Same day / time of day
- Same size area sampled
