Independent Study Component 1 Flashcards
Competition from domestic animals
- invasive species (usually domesticated animals)
- outcompetes native species
Habitat Destruction
- usually wetland drainage for agriculutral land or building
- no shelter for animals -> particularly nesting animals
- no areas for animals to reproduce
Natural Selection
Existing in species do not have the ability to survive in a changing environment
Deforestation
- removal of large areas of rainforest
- destroying large areas of specialised habitat
- causes soil erosion as tree roots bind soil together
- global warming
- less photosynthesis
- cut down trees releasing CO2 into the atmosphere
Habitat Destruction
- wetland drainage for agricultural land or building
- no shelter for animals -> particularly among nesting animals
- no areas for animals to reproduce
Loss of Hedgerows
- increase field sizes for the use of machinery
- destroys wildlife corridors
- as a result herbivore population reduces in numbers
- therefore carnivores that eat these herbivores also reduce in numbers
Pollution (PCBs and Oil)
- unregulated industry polluting rivers
- oil prevents the oxygenation of surface water
- animals (birds) which interacts with the surface of the water of the water feathers clump together and cannot provide insulation
- shore dwelling animals are poisoned
Hunting and Collecting
- collecting for food or profits
- overfishing
can be hunted to extinction
Protecting Habitat & Nature reserves
- prevents biodiversity from being damaged or destroyed
- managed to improve and maintain habitat quality
- act as living gene banks
- maintains natural habitat
Restriction on Trade
- reduce number killed
- Less harvesting of organisms increases biodiversity
- ensure trade specimens if animals and plants which do not threaten the survival of the species in the wild
Zoo Breeding Programmes
- animals on the edge of extinction can be taken into zoos
- animals from several subspecies can breed
animals can be outbred with animals from different zoos - maintaining genetic diversity by deliberate choice of parents
Sperm banks / Seed banks
- damage to ecosystems
- can be used to store specific alleles
- can be sent around the world as part of breeding programmes
- (seeds degrade so periodically samples are thawed and germinated so another generation of seeds can be collected)
Reintroductions
- allows species to be re-introduced into areas where they have been previously gone extinct
- where a a species has been lost individuals can be re-introduced
Why is conservation important?
ethical reasons: the uniqueness of a species is intrinsically valuable
agriculture: conservation of rarer alleles (selective breeding has lost genetic diversity)
conserving alleles that may be useful in the future - medical uses (antibiotics) undiscovered drugs
What is the effect of pesticides on the environment?
- require huge amounts of fossil fuels to transport them
How do pesticides increase agricultural population?
- past epidemics would otherwise occur particularly in monocultures
- reduces competition from other plants
- reduces damage and disease increase yield and quality
How do artificial fertilisers increase agricultural population?
- supplies nitrogen quickly -> essential for crop growth (+phosphate and magnesium)
- higher yields
- nutrients no longer limiting
What is the effect of artificial fertilisers on the environment?
- reduces biodiversity pastures as grass outcompetes wild crops
- eutrophication
How does removal of hedgerows increases the agricultural popualtion?
- more crop space
- allows space for machinery to prepare soil and harvest crops
- allows large machines to work effectively
- reduces labour costs
- faster harvesting
What is the effect of removal of hedgerows to increase field size on the environment
- habitat destruction -> highly specialised habitat which disrupts the ecosystem
- no wildlife corridor
- animal population inbreed
How does drainage of water meadows increase the agricultural population?
- sustaining soil temperatures - to trigger rapid growth
- forest protection nutrient deposits and oxygenation
- more land can be farmed
What is the effect of draining water meadows on the environment?
- loss of biodiversity
- ground water deposition
- flood risk
- soil degrading
- loss of wetland habitat
How do monocultures increase agricultural population?
- higher efficiency and productivity
- easy management
- increased efficiency -> the best use of expensive specialised machinery
What is the effect of monocultures on the environment?
- soil degrading
- heavy use of pedestrians
- pollution of ground water
- less biodiversity
- greater soil deficiency
What are the reasons for deforestation?
- obtaining building material
- clearing land for agriculture / livestock
- high value trees
- new roads
- road and housing development
What are the consequences of deforestation?
- soil erosion - allows wind and rain to blow topsoil into flood plains
- lowland flooding
- less rainfall accelerating denitrification
- habitat loss - accelerating loss of tropical species
- effects of global warming as CO2 is released from decaying trees
- reducing rainfall in tropical rainforest
deforestation is in tropical areas. Why is this a problem?
- cuts indigenous people out of jobs
- accelerates loss of biodiversity
- loss of advantageous alleles
describe the slash and burn method of managing forests
- small forest area is cut and burned
- crops are grown on ash fertilised soil
- when soil is no longer fertile - people leave and the area regenerates over time
Advantages
- sustainable on a small scale
- this clearing can also double as a source of timber
Disadvantages
- not suitable on the scale required today
describe the selective cutting method on managing forests
Advantages
- useful on slopes as removing all trees leads to soil erosion
- helps maintain soil fertility
Disadvantages
- only a small amount of timbre is removed each year
describe long rotation time on managing forests
Advantages
- many years are left between harvesting so variety of habitats and diverse range
Disadvantages
- long between harvesting wood
what steps can be taken to improve efficiency of forestry
- planting trees optimum distance apart (as too close together intraspecific competition occurs
- controlling pests and diseases
- cutting trees on a cycle where areas are left uncut so that wildlife persists so there is sustainable production
Explain how overfishing has resulted in a loss of biodiversity
- introduction of large vessels and new technology allowed more fish to be caught
- fewer fish are able to breed
- reduces prey available to predators leading to predators dying
what are the advantage of exclusion zones?
- maintain biodiversity of the ecosystem
- increased fish population
- food and predators controlled
- breeding grounds are protected
what are the disadvantages of exclusion zones?
- contributes to climate change
- easy disease transmission
- fishermen lose income
what are the advantages of removing subsides?
- reduces overfishing
- improved food security
what are the disadvantages of removing subsides?
- not as many fish available
- loss of income
what are the advantages of fishing quotas?
- limits maximum fish available to be caught (reduces overfishing)
what are the disadvantages of fishing quotas?
- not as many fish available to eat the
- dead fish are thrown back into the ocean when quota is met
what are the advantages of reducing fishing vessels
- reduces effort and range of boats
- reduces overfishing
- reduces ocean oil pollution
what are the disadvantages of reducing fishing vessels?
- oversaturates fish farms
- loss of jobs
- dominance of larger fishing vessels
what are the advantages of reducing fishing times?
- reduces overfishing
- doesn’t over agitate fish population
- allows fish to breed without being interrupted (fishing time isn’t in breeding season)
what are the disadvantages of reducing fishing time?
- not as much available fish
what are the advantages of controlling the mesh size?
- only large reproductively mature fish
- controls the fish population
what are the disadvantages of controlling the mesh size
- doesn’t control disease
- also doesn’t necessarily mean more sustainable as large fish might’ve not necessarily reproduced
what are the advantages of eating MSC fish
- controls marine ecosystems
- sustainability
- traceability
what are the disadvantages of eating MSC fish
- doesn’t really include non traditional fish
what are the advantages eating non traditional fish
- lower contaminate levels
- reduce pressure on overfished species and promote a more balanced marine ecosystem
what are disadvantages of eating non traditional fish
- might impact numbers of non-traditional fish
- some fish need to be transported long distances
why are diseases common on fish farms and why do treatments lead to environment problems?
- farmed salmon are often very dense so easily transmitted diseases
- high does of antibiotics are required to keep the fish healthy
- farmed fish experiences stress due to overcrowding
- treatment is toxic to other organisms
what are some negative effects of fish farming on the environment?
- escaped fish - farmed fish interbreed with wild fish and set up populations which can push wild fish to extinction
- toxins accumulate in the food chain ( can eventually end up in humans
- destruction of groundwater
- eutrophication
- large carbon footprint
what are some positive benefits of fish farming?
- increased food production to try and meet demand
- creates jobs and supports income development
- food security
