BIODIVERSITY
CHAPTER 11
Importance of biodiversity Measuring biodiversity
- all species are interconnected - Tropical moist regions have most biodiversity
- In reduced biodiversity, connections - Closer to equator = greater biodiversity
are not present and eventually harms - Measuring is important in conservation and to determine
all species in the ecosystem effects of changes
- EIA is taken before any buildings (environmental impact
assessment)
Habitat biodiversity - 3 levels at which biodiversity can be studied at:
- The number of different habitats - Habitat
found within an area - Species
- In general, the greater the habitat - Genetic
diversity, the greater the species
diversity
- Eg, meadow, streams, sand dunes, Sampling
woodland, hedgerows - “Taking measurements of a limited number of individual
organisms present in a particular area”
- Can be used to estimate overall no of organisms ie
Species biodiversity abundance
- 2 parts: - Also used to measure a characteristic
- Species richness: no of different - 2 ways: random and non random
species - RANDOM:
- Species evenness: comparison of - Selecting individuals by chance
the numbers of individuals of each - Each individual has equal chance of being picked
species in a community - 1. Mark out grid using tape measures
- 2. Use random numbers to determine coordinates
Genetic biodiversity - 3. Take sample at each coordinate
- Refers to the variety of genes that - NON RANDOM:
make up a species - Opportunistic, stratified, systematic
- Alleles - Conveniently available, split into strata and randomly pick
- Greater genetic diversity = greater from each one, line or belt transect
adaptations
Sampling techniques (animals) Reliability
- must be released at the point they were collected - a sample is never
- Pooter - small insects entirely
- Sweep nets - insects in grass representative due
- Pitfall traps - crawling insects to:
- Tree beating - Sampling bias: can
- Kick sampling - river be reduced by
using random
sampling
- Chance: can never
be completely
removed but is
minimised by using
a large sample
size
CHAPTER 11
Importance of biodiversity Measuring biodiversity
- all species are interconnected - Tropical moist regions have most biodiversity
- In reduced biodiversity, connections - Closer to equator = greater biodiversity
are not present and eventually harms - Measuring is important in conservation and to determine
all species in the ecosystem effects of changes
- EIA is taken before any buildings (environmental impact
assessment)
Habitat biodiversity - 3 levels at which biodiversity can be studied at:
- The number of different habitats - Habitat
found within an area - Species
- In general, the greater the habitat - Genetic
diversity, the greater the species
diversity
- Eg, meadow, streams, sand dunes, Sampling
woodland, hedgerows - “Taking measurements of a limited number of individual
organisms present in a particular area”
- Can be used to estimate overall no of organisms ie
Species biodiversity abundance
- 2 parts: - Also used to measure a characteristic
- Species richness: no of different - 2 ways: random and non random
species - RANDOM:
- Species evenness: comparison of - Selecting individuals by chance
the numbers of individuals of each - Each individual has equal chance of being picked
species in a community - 1. Mark out grid using tape measures
- 2. Use random numbers to determine coordinates
Genetic biodiversity - 3. Take sample at each coordinate
- Refers to the variety of genes that - NON RANDOM:
make up a species - Opportunistic, stratified, systematic
- Alleles - Conveniently available, split into strata and randomly pick
- Greater genetic diversity = greater from each one, line or belt transect
adaptations
Sampling techniques (animals) Reliability
- must be released at the point they were collected - a sample is never
- Pooter - small insects entirely
- Sweep nets - insects in grass representative due
- Pitfall traps - crawling insects to:
- Tree beating - Sampling bias: can
- Kick sampling - river be reduced by
using random
sampling
- Chance: can never
be completely
removed but is
minimised by using
a large sample
size
