Biodiversity Flashcards
What is Biodiversity?
the variety of species in an area
range of different habitats
What is habitat biodiversity?
the range of habitats in which different species live
What is a habitat?
where an organisms lives
What is a species?
a group of organisms that can that can interbreed to produce fertile offspring
What is genetic biodiversity?
the variation between individuals belonging to the same species
what are the three different kinds of biodiversity
habitat biodiversity
genetic biodiversity
species biodiversity
what is species biodiversity?
the range of organisms found in a habitat
What is sampling?
studying a small proportion and multiplying it to get a whole habitat
What is a method to sample animals?
- Look for signs that they have left behind for example footprints, droppings, borrows and nests – droppings can be distinguished by using DNA
What are the different ways to catch invertebrates?
sweep netting, collecting from trees, tullgren funnel, light trap, pitfall trap
How does a sweeping net work?
walking through the habitat with a tout net while sweeping the net through vegetation in wide sweeps. Small animals (insects) will be caught in the net. Then empty the content on a white sheet and identify the animals making sure they do not fly away. To stop them flying away use a pooter
How does collecting from trees work?
spread a white sheet under a branch and knock the branch with a stout stick, this would cause the small animals to fall and then identify them before they fly away
How des a Tullgren Funnel work?
this collects small animals from leaf litter, the lead litter is placed in the funnel and the light above the litter drives the animals downwards, they then fall through a mesh screen to be collected in a jar underneath the funnel
How does a light trap work?
this is used to collect flying insects at night, the ultraviolet light attracts the insect, they then fall into the vessel containing alcohol underneath
How does a pitfall trap work?
this is a small container buried in the soil so its rim is below the surface, therefore any animals moving through the soil will fall into it. To stop the animals crawling out again put a little water in it.
How do you trap small animals?
They can be trapped using a longworth trap (this does not harm the animal) therefore allows the population size to be calculated
How does a longworth trap work?
- Capture animals
- Mark them in a way that doesn’t cause harm
- Release the marked animals and leave traps for the next time
- The number of marked animals on the second occasion is C2, the number of already marked animals on the second occasion in C3
- Total population
What is the estimate affected by?
The estimate is affected by the animals that learn the trap is harmless and has food or by those that don’t like being trapped and therefore keep away
How do you measure species richness? and what is species richness
count all the species
the number of different species present in a habitat
How do you measure species evenness?
carry out a quantitive survey
How do you measure the density?
calculate how many animals of each species there are per unit area
What is simpson’s index?
D=1-(n/N)2