Carbon - EQ3 - Flashcards
How are the carbon & water cycles threatened by human activity
- water pollution
- increased drought
- ocean acidification
- conversion of grassland to farming
Growing demand for food, fuel & other resources have led to…
- contrasting regional trends from land conversion
What is land conversion
- any change from natural ecosystems to an alternative use, it usallu reduces carbon & water stores & soil health
There is a growing demand for food, fuel and other resources globally due to…
- increased population growth
- increased economic growth in NICs/NEEs/MICs (people start to favour meat over rice, etc.)
- improved living standards
Which areas of the world are more affected by changes to land use from resource extraction
- Deforestation and conversion of grasslands to farming is mainly occurring in NICs, LICs and MINT countries
- Afforestation in mainly HICs
What are the implications of land use change
- Changes in forest cover is leading to a decrease in rainfall;
- & the digging up of grasslands reduces the terrestial carbon store,
- having wider implications for the water cycle and soil health..
Give a statistic to say people in developed countries are eating more
By 2030, only 1 in 7 people are expected to be consuming less than 2,500 calories per day
What are the implications for the planet of changing diets
- Grains make up 45% of the world’s diet
- Meat production intensely uses land and water
In 2013 the IPCC estimated that ….% of greenhouse gas emissions came from agriculture and land-use change
24%
Between 1995 and 2005 the global forest area decreased by … million ha, while arable land area increased by .. million ha
- 80 million
- 24 million
Changes in demand leads to changes in land use such as (name 3)
- deforestation
- afforestation
- grassland conversion
What is 1/2 of all deforestation caused by
- soy
- palm oil
- beef
- paper production
Which 5 countries show the highest rates of deforestation globally
- Nigeria
- Indonesia
- North Korea
- Bolivia
- Papau New Guinea
Forests cover …% of the planet although only …% is natural (primary forest)
- 30
- 15
What role do trees play in the water ccyle
- interception, transpiration, rainfall generation & stemflow/ leap drip encourage inflitration & therefore groundwater recharge
What role do trees take in the carbon cycle
- terrestrial store (biomass & leaf litter)
- & CO^2 absoroption during photosynthesis
Define ocean acidification
- involves a decrease in the alkalinity/ ph of oceans, caused by the ocean’s uptake of carbon dioxide from the atmopshere , released by burning fossil fuels.
- The average ocean ph has fallen from 8.2 up until 1800 to 8.1 by 2015.
What are the impacts of deforestation on the water cycle
- Runoff and erosion increase
- Flood peaks are higher and lag time is shorter
- Annual rainfall is reduced
What are the impacts of deforestation on the soil health
- Rapid soil erosion leads to a loss of nutrients
- Raindrop impact washes finer particles away
- Biomass is lost due to reduced plant growth
What is the impact of deforestation on the atmosphere
- Oxygen content is reduced
- Reduced shade means more direct sunlight hitting the floor
- Reduced evapotranspiration which leads to dry air
What is the impact of deforestation on the biosphere
- Reduced carbon store
- Species diversity is reduced
- Ecosystem services are reduced which leads to a decrease in habitats
Why has deforestation occurred in Madagascar and why is it encouraged by the government
- A growing international demand for tropical hardwood, an expanding population and debt repayments
- meant that Madagascan government began to encourage farmers to clear more land to earn money
How are carbon fluxes and stores changed when tropical rainforests are disturbed by deforestation
- Deforestation has a major impact on the size of the terrestrial carbon store
- & also increases the amount of carbon being carried by fluxes such as photosynthesis and respiration
What is afforestation
- refers to planting trees on patches of land which were not previously covered in the forest