resource reliance

• the earths carrying capacity is the maximum number of people the earth can support without creating environmental problems
• the earth can support 3 billion people sustainably however it is now too high so environmental problems are rising
• population grown: since 1950 the world has been in a state of exponential growth and will reach 9 billion by 2050 - higher demand for food leads to more environmental problems and more pressure on land
• climate change - more extreme weather events like el nino mean that farming is harder which affects global food demands
• changing diets - between 2000 and 2010 global meat consumption increased by 5kg per person. this means a higher demand for cows which means more land is used to grow food for cows and less land can be used to grow crops for people so global food demand increases
• types of water:

  blue water - fresh water from river, lakes and seas

  green water- precipitation

  grey water - polluted or recycled water
• physical water scarcity - when a country does not have water supplies to meet demand
• economic water scarcity - when a country does have access to water but cannot afford to access it
• short term physical scarcity is worse but over time rich countries like saudi arabia will develop technology to be able to access the water so therefore long term economic is worse as they will never have enough to access it
• reasons for water scarcity

  rising population: - freshwater demands have increased by 3x in last 50 years. changing lifestyles, eating habits increasing level of red meat which needs 800L of water per pound of beef to process

  climate change: - the decline in mountain glaciers and collapse of polar ice caps led to excessive freshwater melting. decrease in snow fall so fresh water supplies decline
• energy:

  from fossil fuels - coal, gas, and oil - from brokendown plants and animals. they are non-renewable so it is a finite supply and will run out by 2025
• demand for energy:

  overpopulation - average energy consumption has increased by 10% since 2000 especially in EDCs and LIDCs. increased due to industrial revolutions (aisan countries and BRICS)
• subsistence farming - farmers grow food and rear animals for their families to consume - labour intensive
• commercial farming - where food is grown and animals are reared to be sold for profit - technology intensive
• mechanisation of farming

  • positive - more food produced, so more people can access reliable food sources and cheaper through economies of scale
  • negative - biodiversity is reduced by growing a single crop because the ecosystem has less variety of plants, insects, and animals. herbicides and pesticides and fertilisers pollute soil and water sources and get into the food chain. soil erosion increases as more land is exposed to wind and rain. soil nutrients are lost through our farming and are drained away by water (leaching)
• eutrophication:

  impact of fertilisers on water. fertilisers are used to make plants grow faster. but this means they get washed into rivers. the fertilisers cause the growth of algae which takes oxygen from plants and covers the surface so the sun can't reach the plants at the basin of the river and can't photosynthesis to make more oxygen so fish and plants die and the ecosystem in the river decreases (like in the Murray darling)
• commercial fishing:

  • overfishing - more fish caught than naturally replaced - bluefin tuna are nearly extinct - displaces ecosystems
  • bottom trawling - huge nets drag along the ocean floor
  • poison and explosives - cyanide sprayed to stun fish - a square metre of coral per fish is destroyed
  • By catch - 90% of total catch could be - could include century-old coral and over exceed quota so they throw back dead fish
  • fish farms - salmon - half of worlds supply is grown in indoor pools and cages, farms breed disease, waste is flushed into the ocean which spreads disease
• mining:

  • coal mining - results in deforestation, chemicals leaching and freshwater pollution - waste slurry heaps contain mercury and lead - fish die - worse as it is concentrated
  • gas and oil drilling - fracking uses less water than coal power stations and emits fewer greenhouse gasses - reduced USA co2 emissions
• deforestation:

  destroys habitats which destroys the food chain, no variation in soya plantations for biodiversity. Belo monte dam - exploiting amazon rainforest:

  social - 20,000 displaced people, crime rates increase, indigenous are threatened

  economic - 11,000MW of power to 18 million homes, $14 billion

  environmental - 60 HEP schemes, methane produced, reduce water in xingu by 80%
• resevoirs - 3 gorges dam in china

  upstream -

  • land here is flooded, destroying plants and animal habitats. deep water can become "a dead zone" with not enough oxygen for species to survive.
  • diversity of fish is reduced.
  • the dams trap sediment, reducing water quality and covering sites where fish lay their eggs
  • the dam blocks fish migrants in routes. some dams have fish ladders so fish can get upstream
• resevoirs - 3 gorges dam in china

  downstream

  • flooding is reduced to fewer nutrients are deposited - changing ecosystems
  • less sediment means deltas and estuaries are eroded and seawater extends further inland
• water transfer scemes

  the Lesotho highland project in south Africa is a 200km long tunnel. reduces flow of water in orange river and increases the risk of eutrophication. 11,000 hectares of land has been lost
• food security - when people at all times have physical and economic access to sufficient safe and nutritious food to meet their dietary needs and food preferences for an active and healthy life
• physical factors affecting food security:

  • temperature - too hot = not enough hydration so crops don't grow
  • soil - can prevent growth in upland areas - difficult to grow crops
• human factors affecting food security:

  • overgrazing - soil erosion - prevents crop growth
  • poverty - economic access to food
• measuring food security:

  • GNI per capita - shows economic access to food
  • % of the population living on less than $1 a day - shows economic access
  • % of households income spent on food - shows economic access
  • life expectancy - if its low it shows the food they have access to is not safe or nutritious
  • average daily calorie intake - if low, it shows people don't have access to enough food
• Malthusian:

  Malthus's theory - population increases faster than food supply. this will either lead to famine where the death rate increases and population is reduced - positive check, or families will get smaller so less people to feed
• Boserupian

  Boserups theory - when we are close to the limit of food supply it will make people invent new technology and foods so more people can eat - e.g. fish farming created higher yields of fish
• how to increase food security:

  conflict - tacking conflict leads to farming being reestablished (such as UK sending troops to help somalia with al-shabaab)

  reduced food losses and waste - between 1/3 and 1/2 of food produced is never consumed. campaigns encourage people not to care about what food looks like
• case study to achieve food security - tanzania
• Tanzania statistics:

  the amount of food available in 2000 to 2010 is 10% below the Africa food availability. this means serious hunger and it was ranked 89/116 in in the global hunger index
• food security and local scale - goat aid in Babiti

  farm Africa aimed to improve nutrition and income of villagers

  imported Toggenberg goats at the cost of £400 each. they each produce 3 litres of milk a day which makes a surplus of milk which they can sell - this improves economic access for a better life. the milk provides nutrition in diet for healthy life. farm Africa trained villages how to keep care of goats and treat diseases so goats live for longer so constant milk supply for longer period of time so people live healthier and have a balanced diet for longer
• national scale attempt for food security - past tanzania-canada wheat project:

  success:

  • provided 60% of all Tanzanian wheat in 1968 to 1993
  • 150 mechanics gained skills in maintaining farm machinery
  • up to 400 people worked on farms
  • in 1992 drought, Tanzania was the only southern African country not to rely on food aid
• national scale attempt for food security - past tanzania-canada wheat project:

  failure

  • the yield was mostly low and it would have been cheaper to import
  • Canada produced 3.6 tonnes per hectre in 2016 by Tanzania only produced 1 tonne per hectre
  • most Tanzanians eat maize and can't afford bread made from wheat. low-tech maize production might have been more useful
• tanzania-canada wheat project - national scale - past

  overall -not useful in the long term
• south agricultural growth corridor of Tanzania (SAGCOT)

  national scale present day - 350,000 hectare project

  success:

  • 199 commercial farms in 6 cluster areas - high yield = higher food security on a national scale
  • mtenda rice company trained farmers and reduced cost of input. 30 to 200 farms - each getting 25 sacks per acre - helping smaller farms
  • hub and grower model - connected commercial farms to smaller farms for electricity and irrigation = higher yields - improves physical access
• SAGCOT:

  critisim - KPL outgrower sceme paid less than farmers expected for their crops so they fell into dept
• growth corridors

  • lots of rain here with some areas having over 2500mm which is equivalent to a rainforest which helps plants grow
  • soil is very fertile - rich alluvial soil because they are on flood plains of major river systems
• ethical consumerism - when people buy products which have positive, social, economic, or environmental impacts such as fair trade
• food waste - 1/3 of all food is wasted - 1.3 billion tonnes a year