ecosystems case studies Flashcards
summer holiday work on lake district, Antarctica, Galapagos Islands, and Snowdonia
1
Q
human activities in snowdonia
A
- tree felling
- tourism
- made gutters to take water away from paths
- walking/hiking
- introduced rhododendrons to provide cover for pheasant for shooting
- conifers planted
- hydroelectric power station built
2
Q
human activity effect on animal population in snowdonia
A
- rhododendrons invasive makes land unsuitable for grazing livestock
- animals has less vegetation to eat as shrubs kill all the plants in their diet
- littering from tourists can threaten wildlife
3
Q
human activity effect on plant population in snowdonia
A
- rhododendrons can grow tall and block light causing plants below to die
- leaves from plant decompose slowly so accumulate and ruin both soils and bodies of fresh water
- hiking = soil erosion
- farmers drainage ditches causes rain flow quickly increasing flood risk
- conifers dry out moorland as trees absorb water
4
Q
control measures for snowdonia
A
- reduce tree felling
-rhododendrons are burnt - stem injection -> drilling holes into each stem of invasive shrubs and applying herbicides
- park is working with private land owners to limit invasive species
- power station located inside tunnels to minimise impact to environment whilst meeting energy demands
- drainage ditches blocked by haybales
- volunteers have dug drains next to paths preventing flood
5
Q
human activities in Antarctica
A
- tourism
- penguin and krill hunting
- fishing (overproduction) ruining balance of food chains
- poaching
- scientific research
- discharge of sewage into sea
-oil spills - introduction of non native predators threat to birds
6
Q
effect on animal population (Antarctica)
A
- melting of ice caps due to warming of sea
- penguin population reduced due to loss of breeding grounds
- animals have less food to eat due to overexploitation of krill
- hunting of seals + whales
- albatrosses -> baited hooks trail along fisherman’s boat, birds try to eat and accidentally swallow the hook
7
Q
effect on plant population (Antarctica)
A
- global warming effect increases CO2
- ozone thinning
- direct exploitation of ecosystem by over-harvesting alien species
- soil contamination
8
Q
control measures in Antarctica
A
- specially protected areas and exclusion zones (no science/tourist areas)
- krill catchers have a trigger level to prevent overexploitation
- southern ocean whale sanctuary 1994 makes whale hunting illegal in their grounds
- boats use bird weighted lines which sink of reach of birds + avoid breeding and nesting time
- all waste apart from food must be taken away by ship for disposal in other countries.
9
Q
human activity in Galapagos islands
A
-whaling trade - whalers led domestic animals on the loose
- chopping forests for fire
- fishing
- introduced goats (compete with giant tortoises)
- growing in rubbish/sewage
- building housing/agriculture
- oil spill
- national park 1959
10
Q
effect on animal populations (galapagos)
A
- whales killed by hunters
- animals vulnerable to predation, disease, competition and their island doesn’t usually have predators
- fishing disrupts marine environment
- fur traders + whaling boots killed 200,000 tortoises
- 150,000 shark deaths
- alien species can eat native species, destroy their habitats or bring diseases onto island
- e.g. cats hunt iguanas
11
Q
effect on plant population (Galapagos)
A
- disposal creates land and water pollution
- invasive species compete e.g. elephant grass vs endemic daisy trees
- Scalesia trees and shrubs nearly eradicated for agricultural land
- goats transformed forest into grassland = soil erosion
- quinine trees are taller than native species = block light decreasing survival of native plants
12
Q
control measures in Galapagos Islands
A
- introduced park rangers
- limiting human access 36% limited
- control migration from islands
- culling alien species
- inspecting boats for alien species to prevent colonisation
- captive breeding = reintroduction of giant tortoises e.g. charles darwin research station
- chemical herbicides to keep quinine trees in check
13
Q
human activities in lake district
A
- 16 mil tourists a year
- walking
- use of artificial fertilisers instead of hay bales
-walkers trample on vegetation to get passed flood plains
14
Q
effect on animal populations (lake district)
A
- erosion scars = debris into water = death of fish
- trout, salmon, vendace threatened by pollution of spawning grounds
- artificial fertilisers cause loss of species diversity on grasslands
-nesting sites damaged by walkers going off path decreasing bird pop.
15
Q
effect on plant populations (lake district)
A
- walkers walk over vegetation decreasing plant diversity
-concentrated pressure of people trampling ground compacts soil = water doesn’t infiltrate so when rain water runs off soil is taken with it - death of plants + loss of roots with bind soil together
- eroded gullies = walkers off path
- erosion destroyed rare alphine mouse
-soil ends up in water ways and disturb ph of water = eutrophication
