Biodiversity Flashcards
define biodiversity
the variety of living organisms in an area
define species
group of similar organisms able to reproduce fertile offspring
define habitat
the area inhabited by a species (biotic + abiotic factors)
define habitat diversity
the number of different habitats in an area
define species diversity
the number of different species and abundance of each species in an area
define genetic diversity
the variation of alleles within a species (e.g. dog breeds)
define species richness
number of diff species in an area
define species evenness
abundance of each species in an area
sum up the 4 step sampling process:
- chose area (within habitat)
- count no. of individuals of each species (method varies)
- repeat in diff areas
- use results to estimate value
name the sample counting method for plants
quadrat
name the sample counting method for flying insects
sweep net
name the sample counting method for ground insects
pitfall trap
name the sample counting method for aquatic animals
net
how could you make sampling random ?
random number generator to select coordinates
what are the three on-random sampling methods?
systematic / opportunistic / stratified
describe systematic sampling
samples taken from fixed intervals along a transect
describe opportunistic sampling
samples chosen by investigator (simple but data will be bias)
what is a transect ?
line placed across a habitat
describe stratified sampling
when different areas in habitat identified and sampled in proportion to whole habitat
when a habitat has evenly distributed species, it is said to have …
high species evenness
Simpson’s index of diversity is a value between …
0 and 1
the closer Simpson’s index of diversity is to 1 …
the more diverse the habitat
what does n stand for in Simpson’s index of diversity ?
number of individuals of one species
whats does N stand for in Simpson’s index of diversity ?
number of organisms of all species
give an example of populations with low genetic diversity
animals in captivity (isolated populations)
How is human population growth decreasing global biodiversity ? (4 reasons)
- habitat loss (deforestation)
- over exploitation (resources used faster than replenished)
- urbanaisation (cities isolate species)
- pollution (kills species/habitats)
what is mono culture ?
growing of a single variety of a single crop
How is increased mono culture decreasing global biodiversity ? (3 reasons)
- habitats lost for land
- naturally occurring plants / animals thought as pests / weeds so killed
- heritage varieties of crops lost
how is climate change affecting biodiversity ?
changes in conditions may lead to habitat becoming unsuitable for species, causing either migration or extinction
what does it mean that organisms in an ecosystem are interdependent ?
they depend on each other to survive
give two examples of organisms being interdependent
food chains nutrient cycles (less worms in soil reduces quality, affecting plant growth + animal food)
what are keystone species ?
species that other species depend on in ecosystems and without the ecosystem would change dramatically
what are the 3 most common keystone species ?
predators - regulating prey numbers
modifiers - maintain environment (beavers building dams)
hosts - plants that provide environment (trees)
give 4 reasons for maintaining biodiversity:
- protect species
- maintain genetic resources
- reduce soil depletion
- aesthetic / tourism
how does continuous mono culture increase soil depletion ?
uses up all the nutrients in the soil as crops crops are being planted constantly
what does in situ conservation mean ?
on site conservation (in natural habitat)
Give the 5 methods of in situ conservation:
- establish protected areas (restrictions on urban/industrial development and farming)
- controlling species that threaten biodiversity
- protecting habitats
- promoting particular species (e.g. protecting food sources)
- legal protection to endangered species
give the advantage of in situ conservation
both the species and habitat are conserved
give the disadvantage of in situ conservation
difficult to control some factors (poaching/predators/disease/climate change)
what does ex situ conservation mean ?
off site conservation (not natural habitat)
Give the 4 methods of ex situ conservation:
- relocating to safer area
- breeding organisms in captivity then reintroduce them into wild when adult
- botanic gardens for rare plants
- seed banks
give the advantages of ex situ conservation
- can protect endangered animals in a controlled environment
- reintroduce species that have left an area
give the disadvantages of ex situ conservation
- only a small number of individuals can be cared for
- difficult and expensive to sustain right environment
- more likely to catch disease
- many species can’t adapt / breed in new environment
give the aims of Rio Convention on Biological diversity (CBD)
- aims to develop international strategies on conservation of biodiversity and use of animal/plant resources in sustainable way
give the actions of Rio Convention on Biological diversity (CBD)
- made it international law that it’s everyone’s responsibility to conserve biodiversity
- provides guidance to governments on conservation
whats is Convention on International Trade in Endangered Species (CITES) an agreement of ?
agreement designed to increase international cooperation in regulating trade in wild animal and plant specimens
give the actions of Convention on International Trade in Endangered Species (CITES)
- agreed to make the killing of endangered species illegal
- limits trade through licensing
- illegal to trade products from endangered species
- raises awareness through education
Give the aims of The Countryside Stewardship Scheme (CCS)
conserve wildlife and biodiversity
improve and extend wildlife habitats
Give the action of The Countryside Stewardship Scheme (CCS)
government makes 10-year agreements to pay landowners who followed management techniques
