Biodiversity Flashcards
(89 cards)
Define species
Organisms similar in appearance, anatomy, physiology, biochemistry and genetics whose members are able to interbreed freely to produce fertile offspring
Define habitat
The place where an organism lives
Define population
Group of organisms of the same species living in the same area at a particular time
Define community
all the populations of living organisms in a habitat
Define biodiversity
1) range of habitats
2) range of living organisms
3) number of different species
4) genetic diversity
Define species richness
The number of different species living in a particular area
Define species evenness
A comparison of the numbers of individuals of each species in a living area
Why is it that we do not know the exact number of species
We cannot be sure that we have found all species on earth
New species are being found all the time
Evolution and speciation are continuing
Endangered species and extinctions
What does genetic biodiversity mean
The variety of different genes that make up a species
Why is it that a species with greater genetic biodiversity will survive long term
There is a greater range of genes
Greater chance that an organism will survive a change in habitat
Better adapted to catch pray/ avoid new predators
Why is sampling random
To avoid any bias
To make sample representative of an area
Explain the process of sampling species of plant on a field
1) lay out two long tape measures along the sides of study area
2) obtain 2 coordinates using random number generator
3) place quadrant 0.5m^2 at coordinates
4) record % cover
5) repeat many times
6) calculate mean and species diversity
Describe the three non random sampling techniques
1) opportunistic - uses organisms that are conveniently available
2) stratified- sub groups , based on a particular characteristic
3) systematic- often uses a line or belt transects
What is a belt transects
Two parallel lines are marked and samples taken of the area between the two lines
What is a line transect
Place a tape/ rope along the study site
At regular intervals record species touching the line
What is different in a interrupted belt transect
Take numbers at regular intervals
What is a quadrat
What can a quadrat be used to work out
A frame that forms a known area (m^2)
Density, frequency and percentage cover
What is a point quadrat
The apparatus consists of a free standing drama with a row of ten sliding pins
What 3 things can a quadratic be used to work out
Density
Percentage cover
Frequency
What is a point quadrat
A free standing frame with a row of ten sliding pins
These are lowered onto the vegetation
A record is kept of the PIN number and each species of plant that is touching the pin
What scale is used for measuring species abundance
ACFOR
What does ACFOR stand for
A=abundant ( greater or equal to 30%) C=common (20-29%) F=Frequent (10-19%) O=occasional (5-9%) R=rare (1-4%)
Describe a pit fall trap
Used to catch small crawling invertebrates
Like a hole in the ground which has a roof structure so that it does not fill with water
What us sweep netting used to catch
Insects in areas of long grass