4.2.1 Flashcards
What is a habitat biodiversity?
Number of different habitats found in an area
What is species richness?
Number of different species in a particular area
What is species evenness?
Number of individuals of each species living in the community
What is genetic biodiversity how does it happen and what does it lead to?
Variety of genes
Happens due to different versions (alleles)
Lead to different characteristics that allow for better adaptation
What is sampling?
What does sampling tell you?
- Measurement of a limited number of individual organisms present in a particular area
- are used to estimate the number of organisms/And number of individuals of the species (abundance)in an area without counting them
What are the three forms of nonrandom sampling?
- Opportunistic
- stratified
- systematic
What is opportunistic sampling?
It is organisms that are conveniently available (very weak)
What is stratified sampling?
Population is divided into strata (subgroups) based on characteristics then a random sample is taken from each one
What is systematic sampling?
Sample separately carried out using a line or a belt transect
What is the reliability of sampling?
They could be sampling bias
Unfortunate chance that the sample may not be representative of the population
Therefore the larger the sample the more reliable it is
What is a poorer?
Catches small insects
Sucking insects by mouthpiece into holding chamber
What are sweep nets?
Catch insects in areas of long grass
What are pitfall traps?
Small insects fall and cannot crawl out of a hole
What is tree beating?
Cloth is stretched under tree
Tree is shaken or hit and the cloth catches only falling animals/insects
What It is kick sampling?
Riverbank is kicked and the net is placed downstream catches any insects
How are plants sampled?
Quadrat
What is a point quadrat?
Horizontal bar
Each species of plants that the pin touches is recorded
What It is a frame quadrat?
Type and number of species in each small square is recorded
How is species richness measured?
A list of the number of species recorded in a specific area
How do you measure species evenness?
How close the numbers of the population of each species in the environment is
What can you measure using frame quadrat?
- Density
- frequency
- percentage cover
How do you estimate animal population size?
Capture mark release recapture
The greater the number of marked individuals recaptured The smaller the population
What are abiotic factors?
Non-living conditions in a habitat that have a direct effect on the organism
What are six abiotic factors?
What sensor is used to measure them?
Windspeed: anemometer Light intensity: light meter Relative humidity: humidity sensor PH: pH probe Temperature: temperature probe Oxygen content in water: dissolved oxygen probe
Why are senses used to measure abiotic factors? Name 4 reasons
- Detects rapid changes
- human error avoided
- precision
- data stored and tracked on computer
How do you calculate biodiversity and what two factors are taken into account?
Simons index of diversity
species richness/evenness
What are the results of assignment index indicator of?
0: no diversity
1: Infinite diversity
What does low biodiversity tell you?
Few successful species Stressful environments Very specific adaptations Simple food webs Change to environment will have a major effect on ecosystem
What does high biodiversity tell you?
Large number of successful species
Not stressful environment
Few adaptations
Complex food webs
What is the importance of genetic biodiversity and how does it happen?
More alleles means more genetically biodiverse
More likely to adapt, less likely to become extinct
Advantageous alleles
What factors affect genetic biodiversity?
Mutations
Interbreeding (alleles are transferred between two populations, gene flow)
Selective breeding to get advantageous characteristics
Captive breeding
Artificial cloning
Natural selection (advantageous characteristics go through)
Genetic bottlenecks
The funder affects
Genetic drift
What is genetic bottlenecks?
Few individuals survive and events or change reducing the gene pool
What is the founder effect?
Individuals create a new colony that is geographically isolated from the original and the gene pool is small
What is genetic drift?
Random nature of alleles being passed on causes the frequency of the occurrence of the allele to vary
Existence of a particular allele can disappear
It’s more pronounced in populations with a low genetic biodiversity
What is three ways have humans influence biodiversity?
Deforestation
Agriculture
Climate change
What are the issues of deforestation?
Less trees
Less habitats and food for animals
Forces of animals to migrate (decrease in biodiversity)
What are the issues of agriculture?
Farmers grew few crops or plants to get a high yield
Herbicides and pesticides can kill pests reducing diversity
What is monoculture?
Production of one crop
Results in low overall biodiversity
What is the impact of climate change?
Melting ice caps lead to migration
Rising sea levels
Higher temperatures and less rainfall
What are the three main reasons for maintaining biodiversity?
- Aesthetic
- economic
- ecological
What does continuous monoculture result in?
Soil depletion
(reduction in soil nutrients diversity?)
The crop takes the same nutrients out of the soil every year making the ecosystem fragile
What are keystone species?
Why are they important?
Species that play a key role in maintaining the structure of an ecological community
They affect organisms and help
species richness/evenness
They are essential in maintaining biodiversity
What is in situ conservation?
Conservation within the natural habitat
What is ex situ conservation?
Conservation out of their natural habitat
What is sustainable development?
Economic development that meets the needs of people without limiting the ability of future generations to meet their needs
Give examples of techniques that help with in situ conservation. (Seven)
- Controlled grazing
- restricting human access
- controlled poaching
- feeding animals
- reintroduction of species
- calling or removing invasive species
- halting succession
What is Halting succession?
Stopping the natural process where early colonising species are replaced over time
Give examples of ex situ conservation (Three)
- Botanic Gardens
- seed banks
- captive breeding programs
What are captive breeding programs and what do they do?
They produce offspring of a species in a human controlled environment
Aims to create a healthy population of species and gradually reintroduce them into their natural habitat
Why are some of the organisms that are born in captivity not suitable for a lease?
- Disease: they may not be resistant to some new diseases in the world
- behaviour: a lot of behaviour is learnt through copying or experience which they may not have experienced
- genetic races: may not be able to interbreed as their genetic make up is different to the original population
- habitat:1st the habitat needs to be restored to allow captive population is to be re-introduced
What does the international union for the conservation of nature do?
Publish a red list once a year
(Current conservation status of threatened animals)
Countries can work together to conserve the species
What does the convention international trade of endangered species do?
Regulates the international trade of wild plant and animal specimens
What were the three new agreements between nations at the Rio convention?
- Convention on biological diversity: (CBD) developing new strategies for sustainable development (ensure maintenance of biodiversity
- United Nations framework Convention on climate change: (UNFCCC) steps to stabilise greenhouse gas concentrations
- United Nations Convention to combat desertification: (UNCCD) prevent transformation of fertile land into desert
What is the countryside stewardship scheme?
Payment to farmers and other land managers to enhance and conserve English landscape
- sustain beauty and diversity
- improve extend and create wildlife habitats
- restore neglecting land
- improve opportunities for countryside enjoyment
What has the Countryside stewardship scheme been replaced with?
Environmental stewardship scheme
