Studied by 1 personDefine biodiversity
The variety of different living species of organisms on Earth
What does human activity do to biodiversity
Reduce biodiversity and increase pollution by removing land available:
Deforestation
Land used for farming and cattle grazind
Buidling industrial sites
Minind (quarries)
Landfill and waste
Agribusiness
Crops for biofuels
Why is high biodiversity important
Reduces the dependence of one species on another so they do not have limited options and limited effect if one species is lost.
Why do humans live longer
Better technology and medical advancements
Improved diets because of greater food availability and growth
More luxuries and comfortable living due to technology
No natural predators.
Leads to more waste produced
What is bioaccumulation and how does it lead to biomagnification
Bioaccumulation - small toxins build up inside organisms to dangerous levels. As other trophic levels eat it, they pass the toxic chemicals down until it gets built up much more higher up in the food chain, known as biomagnification
What are the causes and effects of water pollution
Untreated sewage:
- In places with lack of sewage systems
- Sewage runs off into rivers and seas
- Releases bacteria which start aerobically respirating and feeding on dead animals and plants which have died due to the toxic chemicals
- Reduces dissolved oxygen levels in water
- More fish and plants die
Release of toxic chemicals like herbicides and pesticides
Fertilisers run of into the water:
- more underwater plant and algae on surface growth
- blocks sunlight
- Underwater plants die
- Bacteria can rapidly reproduce and break it down.
- Aerobically respire and reduce dissolved oxygen levels in water
- Fish and plants die
What are the causes and effects of land pollution
Landfills - waste. Destroy habitats
Industrial development: buildings, quarries, farms.
Toxic chemicals pollute soil and disturb its pH. Soil may become infertile
Soil erosion
Bodily waste - gut parasites
Industrial waste
What are peat bogs and what are they used for
Contain large amounts of dead plants and animals that bacteria were not able to decompose due to the cool, wet, acidic conditions. Have trapped carbon and decay very slow.
Produce cheap compost
Burnt for energy -? release CO2
Destruction of environment when obtaining them.
What are bioindicators
Clean water: salmon, stonefly larvae
Somewhat clean: shrimp, water lice
Polluted: rat-tailed maggot, bloodworm
What are intertidal zones
regions at seashore above sea level at low tide and below at high. Habitats for Barnacles
What are the causes and effects of air pollution
Burning fossil fuels. Release CO2, sulphur dioxide and nitrogen oxide
When burning, sulphur and nitrogen impurities released which react with the oxygen. Dissolve in rain.
Can cause acid rain which is dangerous and harmful to plants and animals. Roots destroyed, seeds won’t germinate, plants killed, limestone erosion, aluminium in soil activated which kills
Acid rain pH lower than 5.5
Normal rain also acidic due to CO2
Clean flue gases before leaving atmosphere
Use gas, not coal
Smog: Smoke and chemicals. Haze of small particles and acidic gases
Smoke pollution: particles damage lungs. Dimming effect and cooling of temp.
What are catalytic converters
convert SO2 and NO2 to CO2 (less harmful) in exhaust fumes
What is meant by peer-review
Detect false claims and make sure research published is valid
How does global warming happen
Increased CO2 and methane levels (greenhouse gases). These gases absorb Sun’s heat and trap it to keep surface warm. Too much means too much heat absorbed.
What is methane released by
Rice fields
Cows
What are the effects and environmental changes of global warming
Affect migration patterns of animals
Affect species distribution and ecosystem: more mosquitos moving away from equator
SO2 and NO2 cause acid rain
Reduce biodiversity as habitat loss
Change in temp.
Change in water
Change in seasons
Human interaction: pollution but also conservation and sustainability
Natural disasters
Geographical location: soil pH, plants and animals.
How can we maintain biodiversity
Breeding programmes: restore endangered species to sustainable population. Must avoid inbreeding. Due to habitat loss
Reforestation
Recycling
Reintroduction to field margins and hedgerows: Allows variety of birds, plants and animals. Soil erosion and infertility without it
Reduction of deforestation and CO2 emissions
Government taxes on putting material in landfill
Protection and regeneration of rare habitats: protects biodiversity (coral reefs), E.g. reflooding wetlands. Game reserves and national parks
What is meant by trophic level
position of organisms on a food chain.
What is an apex predator
carnivores with no predators
How do decomposers release mineral ions back to soil
secrete enzymes in environment. Enzymes digest dead materials. Small soluble food molecules diffuse back into decomposer.
What is biomass
Weight. Needed for survival and cellular processes.
Why do we use ‘dry mass’ for calculating biomass
No water content and moisture content measured as it can vary widely for different organisms and produce inaccurate results.
How much light is actually absorbed for photosynthesis
1%
How much biomass is actually passed on from one trophic level to next
10%
How can biomass be lost
Egestion - solids
Excretion - liquids
Cellular respiration (growth, movement, heating)
What is the difference between pyramid of biomass and pyramid of numbers
pyramid of biomass: looks more like a pyramid. Bottom one biggest and top the smallest
Pyramid of numbers: bottom the smallest(large tree), middle much bigger(lots of aphids), top a bit smaller than middle(ladybugs)
How to calculate efficiency of biomass
(biomass transferred to next level/biomass available at previous level) x 100
What in the food chain has the greatest biomass
Decomposers. Digest waste, dead plants and animals
What does it mean to have food security
Having enough food to feed a population
What are the factors affecting food security
Increasing birth rate
Changing diets in developed countries
Climate change - unpredictable weather
Cost of agricultural inputs
Conflicts affecting access to water/food
What are the problems with free-range animals reared outside
much of biomass used for keeping constant body temp, respiration, energy
Slow growth
More space
Better quality
Weather problem
No heating/lighting costs
How long should food chains be
short with less stages
What is intensive farming
Agricultural farming methods aimed to maximise production and reduce amount of biomass lost in food chain
How is intensive farming done
Feed animals high-protein food for fast growth
restricted movement and limited space
Controlling surrounding temp
What are the pros and cons of intensive farming
Pros:
Less biomass lost = more food
Eggs more easily harvested indoors
Cons:
No animal welfare so ethical issues. Unnatural.
Stress = more animal fights = bad for growth
Risk of disease spreading quicker = anti biotic resistant bacteria may develop.
What is meant by sustainable fisheries
Maintain fish stocks at level which is sustainable and breeding continues otherwise some species may disappear.
Control net size so small, immature fish not caught
Strict quotas limiting amount of fish that can be caught of each species
Ban fishing in breeding season
What is meant by biotechnology
Using living organisms and biological processes to to make products for industrial purposes
What are 2 examples of biotechnology
Allow large quantities of microorganisms to be cultured for food
GM bacteria: produce drugs (insulin) on larger industrial scale
What is meant by mycoprotein
Protein-rich food that can be eaten by vegetarians. Produced by fungus ‘Fusarium’. Grown on glucose syrup aerobically in fermentor and biomass harvested and purified.
Grow loads in small spaces so efficient.
Note
Flashcard