Lecture 20 - Ecosystem Services and Environmental Change Flashcards
What are ecosystem services?
The benefits to humankind provided by natural ecosystems.
What is the causal chain of ecosystem services?
Biodiversity –> ecosystem functioning –> ecosystem services –> human wellbeing
(arrows = influence)
What is option value?
Keeping biodiversity because it might have some benefit in the future.
Give four groups of ecosystem services.
- Provisioning
- Regulating
- Cultural
- Supporting
What is provisioning ecosystem services?
Direct use values of biodiversity - products produced by natural environment.
What are regulation ecosystem services?
Benefits obtained from ecosystem processes that contain natural dynamics within bounds.
Indirect use values of biodiversity.
Who defined the four main groups of ecosystem services?
Millenium Ecosystem Assessment
What are supporting ecosystem services?
The services that are required for all other services to be provided.
Give at least three provisioning ecosystem services.
- Food
- Fibre
- Fuel
- Fresh water
- Genetic resources (e.g. in selective breeding)
- Natural medicines
- Ornamental resources
Give at least three examples of things that regulation services can regulate.
- Air quality
- Climate
- Water purity
- Floods
- Erosion (e.g. mangroves regulate risk of erosion)
- Disease
- Pests
- Natural hazards
Give some examples of supporting services.
- Nutrient cycling
- Soil formation
- Photosynthesis
- Primary production
- Water cycling
- Pollination
When was the Millennium Ecosystem Assessment published?
2005
What are the four components of human wellbeing?
- Basic materials for good life
- Health
- Good social relations
- Security
- Freedom of choice and action
What kind of ecosystem services is health most likely to depend on?
Regulating ecosystem services.
What is the largest indirect driver of change?
The size of the world population.
In the past 500 years, how much higher are extinction rates of mammals, birds and amphibians than shown in the fossil records?
1000 times higher
What was the island of Easter Island originally covered in?
Palms
When was Easter Island inhabited by humans
400 A.D.
Why did human culture collapse on Easter Island?
Overexploiting natural resources on Easter Island, leading to collapse of biodiversity, thus the collapse of human livelihood and culture.
What are the 5 main threats to biodiversity as defined by the Millennium Ecosystem Assessment?
- Habitat change
- Climate change
- Invasive species
- Overexploitation
- Pollution
Out of the combinations of biomes and threats, how many are not worsening?
18/65
Why is the temperature forest habitat change improving?
Due to reforestation methods – deforestation here happened some time ago.
Which two threats have the most rapid increases across all biomes throughout the 20th century?
- Climate change
- Pollution
What percent of the terrestrial surface has been cultivated?
24%
What can the removal of nutrients from the soil lead to?
Desertification – unproductive land.
In the USA, how much faster is soil being lost than it is being reduced?
8 times.
Why has there been increased occurrences of flooding?
Changing vegetation, reduced capacity of natural environment to tolerate water.
By what methods do humans introduce alien species to parts of the world?
- Deliberate and desirable; ornamental, production of food, for hunting, as pets.
- Accidental; stowaways in shipping, from international movement of agricultural products.
In the UK, approximately what percentage of plant species that occur in these regions are not native?
40%
Of all the species introduced to a region, what percent of them manage to become established?
10%
Of the invasive species that become established, what species are able to become ‘nuisances’?
1%
In the UK, how many non-native species are there belonging to the following groups?
a) Mammals
b) Birds
c) Reptiles
d) Amphibians
e) Fish
a) 23 mammals
b) 24 birds
c) 3 reptiles
d) 7 amphibians
e) 14 fish
How many invasive plant species in the UK cause major impacts?
9
Give two UK species that enrich our natural environment.
- Little Owl
- Horse chestnut
How does the African Landsnail affect the ecosystem?
Consumes natural vegetation.
Give two plant species that can outcompete natural vegetation.
- Guava
- Lantana
How do populations of grey squirrel affect populations of red squirrel?
Grey squirrels are a reservoir of the parapox virus, which has a greater effect on the red squirrels.
What was the effect of brown tree snake?
Leading to reduction in numbers of native bird species.
What has overexploitation of marine ecosystems lead to?
- Collapses of fish populations.
- Collapses of non-raget species = “by catch”.
Give an example of a by catch.
Loggerhead turtles
What effect does overfishing have on bushmeat?
Increases pressure to consume bushmeat.
Give a major driver of declines of native plants in western Europe.
Nitrogen enrichment in grasslands.
