Biodiversity Flashcards
Define ‘species’
A group of organisms that can interbreed to produce viable offspring
Define ‘population’
Group of organisms of the same species in one area at one time
Define ‘community’
A group of populations living/interacting in an area
Define ‘habitat’
The environment where a species normally lives
Define ‘ecosystem’
Interactions between abiotic and biotic factors
Define ‘biodiversity’
The variety of species in an area
Define ‘habitat biodiversity’
The range and variety of habitats in an area
Define ‘species biodiversity’
Variety of species in an area
What are biotic factors?
Living factors; competition, predation, paracyticism and mutualism
What are abiotic factors?
Non-living factors; climate, wind, humidity
Why is biodiversity so important?
Maintaining ecological, economical and ethical factors
What are some ecological factors for why biodiversity is so important?
Pollinators, habitats, disruption of food chain and nutrient cycles
What are some economical factors for why biodiversity is so important?
Medicine, food, clothing, fuels, agriculture, ecotourism, scientific research
What are some ethical factors for why biodiversity is so important?
Prevent extinction, indigenous populations, moral responsibility, aesthetic reasons
What is species richness?
Describes the number of different species present in an area (more species = richer)
What is species evenness?
Describes the relative abundance of the different species in an arear (similar abundance = more even)
What are some of the threats to biodiversity?
Pollution, loss of habitat, non-native species (trade), overexploitation, climate change
Define ‘genetic biodiversity’
The variety of genes in a species
What is sampling?
A technique used to estimate the population of individuals in an area without having to measure them all (abundance of a particular species)
What is random sampling?
A technique where individuals have equal chances of being selected; using grids and random numbers to place quadrats
What is non-random sampling?
Not chosen at random, so; opportunistic, stratified and systematic
What is opportunistic sampling?
Counting/recording organisms that you happen to see/most conveniently available
What is stratified sampling?
Divided populations into groups (strata) based on characteristic then taking a samples from each group; separating into female and male
What is systematic sampling?
Different areas within a habitat are identified and then sampled separately; line + belt transects
What is the difference between line and bel transects?
Line transects only measure what is directly touching the line, however belt transects take samples with quadrats and so measure a larger area (giving more info)
How does reliability affect sampling?
Sampling bias and chance; choosing a sampling area because it looks more interesting or area sampled may not be representative of population
Name some ways to sample animals
Pooter (sucking on mouthpiece to draw insects into chamber), sweep nets (used on long grass), pitfall traps, tree beating (so insects fall from tree), kick sampling (disturbing river bed to catch organisms)
Name some ways to sample plants
Point quadrat (counting whatever a pin touches) and frame quadrats
For frame quadrats, what is density?
Density of organism per 1m^2
For frame quadrats, what is frequency?
Counting in how many of the squares an organism is present, if the organism is hard to count (like grass or moss), and then figure out a percentage (so if present in 40 out of 100 squares, the frequency of occurrence is 40%)
For frame quadrats, what is percentage cover?
Estimate of the area a plant species covers in a quadrat, similar to frequency
How would you estimate an animal population size?
Capture-mark-release-recapture, comparing number of marked and unmarked organisms upon recapture (bigger number of unmarks = larger population)
What are abiotic factors?
Non-living conditions in a habitat that directly effect organisms, e.g. wind speed, light, humidity, pH, temperature and oxygen concentration
How would you measure abiotic factors?
light - light meter
pH - pH probe
temperature - thermometer/temp probe
Name some factors that increase genetic biodiversity
Random genetic mutations, interbreeding (gene flow)
Name some factors that decrease genetic biodiversity
Selective breeding, captive breeding programmes, rare breeds, artificial cloning (farming), natural selection, genetic bottlenecks, founder effect
What is a genetic bottle neck?
Where a small group within a population survive a change (natural disaster, disease) that reduces the gene pool
What is the founder effect?
Where a small number of individuals create a new ‘colony’ that is geographically isolated from the previous population, so the gene pool is smaller
What are some of the factors that effect biodiversity?
Deforestisation, climate change and agriculture
How does deforestisation affect biodiversity?
Species diversity (of trees) is reduced, decreases habitat biodiversity, makes animals who rely on habitat for shelter and food vulnerable
How does climate change affect biodiversity?
Loss of ice caps as habitat, decrease in species biodiversity as habitats are lost, decrease in rainfall = drought, loss of pollinators means loss of plant species
How does agriculture affect biodiversity?
Removal of hedgerows, use of chemicals (herbicides and fungicides), monocultures (lowering species/habitat/genetic biodiversity)
What are hedgerows?
Areas of hedges/trees that act as shelter and food source for many organisms, often are destroyed to make more room for agriculture
What are the main reasons we should maintain biodiversity?
Ecological, economic and ethical reasons
What are the ecological reasons we should maintain biodiversity?
Maintain food chains and nutrient cycles, prevent deforestisation and climate change, maintain habitats and pollinators
What are the economic reasons we should maintain biodiversity?
Ecotourism, scientific research, potential in useful species, biofuels, prevent soil erosion and desertification to maintain crop growing,
What are the ethical reasons we should maintain biodiversity?
Aesthetic reasons (mental well-being), prevent extinction (man has no right to take life away from Earth), morally responsible for future
What are the different types of biodiversity conservation?
Ex situ and in situ
What is ex situ?
Conservation outside of the organism’s natural habitat
What is in situ?
Conservation inside of the organism’s natural habitat
What are the different types of species conservation classifications?
Extinct, extinct in wild, endangered and vulnerable
What are some examples of in situ conservation?
Wildlife reserves (controlled grazing, restricting human access, controlled poaching, feeding animals, culling invasive species), marine conservation zones
What are some examples of ex situ conservation?
Botanic gardens, seed banks, captive breeding programmes
What are some of the negatives of captive breeding programmes?
Recessive diseases due to small gene pool, change in behaviour and genetic races (so cannot be reintroduced into the wild)
Name some conservation agreements
International Union for the Conservation of Nature, The Rio Convention, Countryside Stewardship Scheme
