How threatened ecosystems can be audited?
- Economic scorecard (shows an ecosystem’s ability to produce goods and services)
- Living Planet Index (monitors changes overtime in forests/marine)
- EFP (measures human impact on planet)
- Red List of Endangered Species
- Millennium Ecosystem Assessment (multi scale assessment commissioned by the UN)
What is a terrestrial eco-region?
A large area of land containing distinct assemblies of species, natural communities and habitats.
Where are the most threatened biomes?
In the temperate zone as they have a long history of human settlement and they are the most economically developed.
Where is the threat shifting to?
The tropics as there is high population increase so high resource exploitation.
Where is the least threatened areas?
Where there is very high latitude
Tundra and boreal forests are relatively unthreatened
What are the factors maximise the threats of biodiversity?
- unsustainable high rate of population rise and natural resource consumption
- Poorest areas are threatened due to inequality, poor management and flow of benefits
- Agriculture, forestry, fishing on a narrow spectrum of products
- Government and business are ignoring environment and developing economically instead
- Unsustainable exploitation is promoted by legal institutional systems
- There is a lack of knowledge and understanding for the conservation of biodiversity
What global threats are there?
CLIMATE CHANGE (Stern Review)
DEFORESTATION
What are the effects of CC on biodiversity?
- Vegetation is shifting northwards
- Coral bleaching & ocean acidification results in coral reef damage
- Species extinction
- Rising sea levels results in loss of coastal wetlands
- Mangroves get flooded and the natural coastal defence is removed
- Tropics are drying resulting in rainforest damage
- Pest and disease risk
What are the effects of deforestation on biodiversity?
Indigenous resources are threatened There are knock on effects on food webs Nutrient cycling Soil Erosion Flooding
What local threats are there?
- Fires to clear forests (for settlement and development, cattle grazing, soya bean production, farming practices slash and burn)
- Controlled fires (management tool to ensure succession in National Parks or to maintain heather in Scotland for example)
- Habitat change (overexploitation, agriculture, mineral working, urban growth)
- Recreational Use (Trampling, animal disturbance, depends on carrying capacity of the area, the level of use and the management of recreational use)
- Mineral exploitation (Extraction, holes and toxic spoil)
What are the two ecosystem processes?
Energy Flows (food pyramid) Nutrient Cycling
How can energy be lost?
Respiration
Decay
Excretion
Egestion
What are the 3 stages and transitions in nutrient cycling?
Litter (decay) Soil (plant uptake) Biomass (decomposition)
How is litter removed and produced?
Produced by precipitation and removed by runoff
How is soil removed and produced?
Produced by weathering and removed by leaching
Why do alien species threaten species movement so much?
- they have enhanced survival rates and more efficient competitors than native species
- they lack native predators
- they are not susceptible to indigenous diseases
- difficult to control as they spread fast
- harm existing food webs
What are some examples of deliberate introduction of alien species?
- pheasants/rainbow trout for sporting purposes
- rhododendron (from india) for scenic purposes
- hedegehog (from Scotland) to deal with the slug plague
What is the negative of rhododendrons in the UK?
They hinder the development of natural vegetation and woodland vegetation
What is the negative of hedgehogs in the UK?
Feed on the eggs of ground nesting birds so their pop. decreased
What are some examples of the accidental introduction of alien species and what damage did they cause?
- zebra muscle on ships from North America:
they reduced to phytoplankton by 80% so less light to algae and reduced water quality
they cling to each other and blocked water inputs and outputs so the power stations had to be shut for cleaning - snakes to Guam via air transport
What is the difference between destruction and degradation?
Destruction: total clearance
Degradation: loss of quality
Where is degradation more likely?
In large ecoregions where they may not totally clear nit degrade such as savannah areas of Africa and rainforests
What are the stages of degradation and what does the graph look like?
1 - pristine system with indigenous using the area and living there
2 - maximised rate of industrial development so massive pollution and resource consumption
3 - eco-awareness develops and conservation strategies financed and improved
4- more sustainable development so ecosystems survive
What are the roles of mangroves?
Reduce erosion Storm protection Reduce sediment runoff to reefs provide shelter for small fish (nurseries) to avoid predators Home to barnacles
