Human Impact On The Environment Flashcards
Define the term endangered
A species which has few numbers in total population. At risk of extinction.
Define the term extinction
There are no living organisms of that species left
Define the term conservation
The protection, preservation, management and restoration of natural habitats and their ecological communities while allowing suitable human activity
Define the term ecotourism
Responsible travel to natural areas that conserves the environment and improves the well being of local people
Define the term monoculture.
The growth of large numbers of genetically identical crop plants in a defined area
Define the term soil erosion
The removal of fertile topsoil which contains all of the valuable nutrients
Define the term coppicing
Cutting down of trees close to the ground and leaving to regrow for several years
Define the term over fishing
The rate at which fish are harvested is greater than the rate of reproduction.
Define the term planetary boundaries
Limits between which global systems must operate to prevent abrupt and irreversible environment change
Define the term core boundary
Crossing this boundary would drive the earth into new and unpredictable state with severe consequences for the biosphere
Define the term global warming
The increase in global average temperature in excess of the greenhouse effect caused by the atmospheres historical concentrations of co2
Define the term biofuel
A fuel made by a biological process like anaerobic digestion rather than geological processes that formed fossil fuels
List some causes of extinction caused by humans
- deforestation
- habitat destruction
- over hunting
- competition from introduced species.
List some conservation methods
- legislations to prevent overhunting or overfishing
- seeds and spent banks
- habitat protection and nature reserves
- breeding endangered species in zoos
Why do we want to conserve species and gene pools at risk of becoming extinct?
The species could give useful genes to aid humans for medical use if qualities are not yet known
What are some reasons for deforestation?
- to sell high quality/valued trees like mahogany
- timber used as fuel or building material
- clear land for farming or cattle grazing
- space for roads and housing
List some consequences of deforestation
Reduced biodiversity
Habitats are destroyed
Soil erosion
Lowland flooding
How can forests be managed?
Coppicing Conservation Controlling pests and disease Selective cutting Log rotation time
What is overfishing?
When fish are harvested faster than they can reproduce to repopulate so populations decreases
What measures can be put in place to prevent overfishing?
Quotas Seasonal fishing Restricted areas Legislation on net mesh size Legislation of boat numbers in a fleet
Describe the steps of eutrophication
- nitrates form fertilisers leached into lakes from soil
- plants respond to fertiliser in the water causing an algal bloom
- this causes restricted light to the aquatic plants so unable to photosynthesis was much so they die and lack of oxygen in water
- these pants are decomposed by saprobionic fungi which creates a lack of oxygen in the water as they use it to respire.
Why is environmental monitoring needed?
It will describe the quality of the environment to help identify patterns in data to help make future predictions.
What are some advantages of biofuels?
Reduces loss of fossil fuels and carbon dioxide emissions
Can use waste products from farming to be more sustainable.
List some disadvantages of biofuels
- uses land which could be used by crops for food or wildlife
- deforestation to make space to grow crops leading to erosion and reduced biodiversity
- biodiesel produces more NO2
- fossil fuels still used like for transport, processing and harvesting.
What is natural selection?
Occurs when individuals less suited to prevailing conditions reproduce less successfully
Their numbers decrease which may lead to extinction
How does human activity affect natural selection?
Human activities are causing habitats to change faster than mutations allow species to adapt, so they are driven to extinction at a faster rate than before human influence.
Name some methods of habitat destruction
Deforestation, drainage of wetlands, hedgerow removal
How does hedge row removal destroy habitats for other organisms?
They provide habitats for insects, nesting sites for birds and reptiles, food for many species, varying light intensity and water availability for diverse plants. Shelter for animals moving around from predators
Why are hedgerows removed?
Space for large agricultural machinery
Give examples of overhunting and collecting
Trophy hunting Traditional medical practices Bush meat industry Overfishing Agricultural exploitation
Give examples of how competition from reintroduced species have caused threats to other species
- dodo driven to extinction due to rats from European ships eating the eggs
- red squirrels out competed by grey squirrels in uk due to loss of habitat
How is pollution putting species at danger of endangerment and extinction?
- oil shipped worldwide in supertankers, accidental discharge of oil in sea when ship runs aground. Contaminated potable water and killed plants and animals
- oil floats on surface of water, so when animals break through the surface of the water, they are covered by a film of oil. And washed up on shore and ingested by animals which are ten poisoned
- PCBs are infested with food can still be detected in waste water around old quarry’s even through they were banned.
What is conservation?
The sensible management of the biosphere to maintain habitats and enhance biodiversity while allowing human activity.
Why is conservation important?
To maintain genetic diversity both in the wild and in captivity.
List methods of conservation
- nature reserves
- international cooperation restricting trade
- breeding programmes (zoos and botanic gardens)
- sperm banks
- seed stores
- reintroduction programme
Explain the importance of nature reserves and sites of special scientific research
For habitat protection
It protects the species that live there and the community acts as a living gene bank
Official designation recognised local nature reserves sometimes as small as a few hectares
Explain the importance of international cooperation restricting trade
Like the ivory trade and whaling
International laws allow some countries to practice whaling although there are many organised attempts to stop it.
Explain the importance of breeding programmes like zoos and botanic gardens
For endangered species like pandas which are protected and entered into breeding programmes in specialised zoos and botanic gardens
Records of mating are kept so genetic diversity can be increased by deliberate choice of parents to form a gene bank.
Explain the importance of sperm banks
Used to store genes of economically important animals and threatened species
Rather then moving animals, sperm samples are sent around the world to use in breeding programmes of other zoos
Explain the importance of seed stores during conservation
Maintain stocks of seeds of traditional varieties and of vulnerable species in highly controlled conditions of liquid nitrogen.
Seeds degrade over time so periodically seeds are thawed and germinated and a new generation of seeds is collected and stored from there.
Explain the importance of the reintroduction programme during conservation.
Following successful breeding programmes some species are reintroduced into the wild and former habitats like the red kite and the chough
Describe ecotourism and how it helps conservation
It recognises that mass travel is harmful globally and to specific habitats. It aims to:
- contribute to conservation efforts
- employ local people and give money back to local communities
- educate visitors about local environment and culture
- cooperate with local people to manage natural areas.
Why should existing gene pools be conserved?
- ETHNICALLY each species is unique band valuable
- AGRICULTURE selective breeding loses rare alleles and some past breeders may have neglected qualities like agriculture
- ENVIRONMENT changes. Some alleles are advantageous to the individual to survive changes in the environment.
- MEDICAL many antibiotics are derived from fungi and plants. If species become extinct we may lose potential drugs we haven’t yet discovered.
Define agricultural exploitation
Producing that quality and quantity of food required to feed the increasing human population.
