LECTURE 10 Flashcards
Name the four kinds of ecosystem services.
Provisioning – water and food supply
Supporting - maintenance of other ecosystem services (nutrient recycling, primary production)
Regulating – maintenance of planetary processes (esp climate system)
Cultural – recreational or spiritual benefits
Five Examples of Ecosystem Provisioning Impacts
Food provisioning (from marine systems)
Food provisioning (from marine systems) • Marine fisheries
- Water temperature is correlated with fluctuations in population size for many species (mackerel, sardine, salmon)
- Catch size fluctuates with indices of atmospheric circulation and water temperatures
- More than 50% of fish caught in Pacific and Atlantic are influenced by indices
- Climate change affects atmospheric circulation and water temperature and affects catch size in the future
Food provisioning (from marine systems)
Warming oceans reshaping fisheries
Warming oceans reshaping fisheries
Subtropic and temperate oceans
• Shifts towards more warm-water species and fewer cool water species
Tropics
• Declines in warm-water species because there are not may species with high enough temperature preference
Food provisioning (from marine systems)
Patterns in sardine and anchovy catches
- The catches track: global temperature trends (g) and local atmospheric circulation indices (b-f)
- Species differ
o Cool periods saw an increase in Peruvian anchovy catch
o Warmer period saw an increase in sardine catch
Temperatures oscillate on a 25-year cycle (large scale climate changes)
Sardine-anchovy Cycle
- Changes in catch are linked to 25-year cycle
- Collapse of California sardine fishery = entire processing industry lost
- Changes in Peruvian anchovy fishery = thousands of jobs and millions of tons of food impacted
*Note: not all populations react in the same way
- In California, sardine catch increases in warm period / low productivity
- In Japan, sardine catch increases in cold periods / high productivity
- The mechanisms behind this are being studied
Five Examples of Ecosystem Provisioning Impacts
Water provisioning
Water stress – surface water used by humans (domestic, industrial, agricultural) is greater than 40% available water
Climate: rainfall and temperature
Decrease in rainfall = decreased stream flow
Increased temperature = increased need for water
~ 2 billion people = water stress conditions (2011)
2/3 of global population = water stress (2025)
What is water stress?
Water stress – surface water used by humans (domestic, industrial, agricultural) is greater than 40% available water
Climate change / population change = changes in water stress
Climate change / population change = changes in water stress
• Water stress calculated GCM & water basin model
- Many areas ↑ stress due to climate change
- Other places precipitation ↑
- Many areas ↑ stress due to ↑ population
- Overall trend of ↑ in stress globally
The third world war will be about _______
The third world war will be about water (fought over oil in the past)
We need to change our approach to managing this vital resource
Which water climates are at risk?
Mediterranean climates at risk
- California, Chile, SW Australia, cape of South Africa, areas around Mediterranean sea
• Where water is already naturally scarce
• Centres of wine production, good agricultural potential
• High human population, leading to water stress
Increased summer droughts and increased temperatures = increased aridity = increased water stress
Southern Europe – about 40% of Mediterranean populations increase water stress by 2050
Increased water use (for purpose of agriculture and tourism) as temperatures increase = further increase in water stress
What are the impacts of melting glaciers?
CHANGES IN WATER AVAILABILITY (STREAMFLOW!)
o Increased short term, decreased long term
o Increase in seasonality of water supply
POLAR / HIGH LATITUDE
o Increased impact on ecosystems
o Decrease impact on human populations due to water stress (few people live in these areas)
TROPICS
o Increased impact on ecosystems and human populations
Give an example of the impacts of melting glaciers.
Andean Altiplano
• In Andes, bofedales and paramo are extensive
o Bofedales – high altitude wetlands that absorb and retain water (compensate for glacier melt)
o Paramo – alpine grasslands, also retain water
- Major cities rely on water subsequently, they rely on glacial meltwater and bofedales/paramo reserves
- Manage ecosystems to maintain water reserves
What are bofedales?
Bofedales – high altitude wetlands that absorb and retain water (compensate for glacier melt)
What are paramo?
Paramo - alpine grasslands, also retain water
Why are bofedales and paramo important?
Bofedales – high altitude wetlands that absorb and retain water (compensate for glacier melt)
Alpine grasslands, also retain water
Major cities rely on water and subsequently, they rely on glacial meltwater and bofedales/paramo reserves
T or F: Himalayan glaciers are declining.
True - Himalayan glaciers are declining.
Lifting cloud base & cloud forests
• Cloud forests –> trap water (fog), runoff flows downstream
• If the cloud base lifts up, then the fog and forest intersection decreases and less water
• Less cloud forest coverage
• Increase water stress downstream
What impact do melting glaciers have on Snowpack-dependent Systems?
Snowpack-dependent Systems
Increased temperatures = less snow
- Earlier spring earliet snow melt
- Later fall later first snowfall
Impact to streamflow for downstream ecosystems
- Increased in peak flow and earlier peak flow
- Decrease in water availability later in the water year
Impacts rich agricultural lands in USA
14-fold increase in USA counties with extreme water stress by 2050
Other temperature regions at risk (arid and semi-arid areas)
Increased in water stress increased risk of fires