Theory

• Describe the rate of population growth 1750 - 2100:

  • 1750 - 1950 had a massive exponential increase, especially growing from 5 million in 1950 to 7 million in 2010
  • UN Projection shows a projected plateau.
  • The rate of growth is halved from 1900 - 2000 to 2000 - 2100

  
• What reasons are behind Population Growth & Changes?

  • Globalisation
  • Industrial Revolution
  • Societal Changes (post WW2 attitude)
  • Increased infant mortality

  
• Example of an area with high Population density: Lagos, Nigeria

  • Has a population of 15 million, with an annual growth rate of 2.41%
  • Population Density = (6871 residents / km2)
  • The city has the 4th highest GDP in Africa + one of the largest seaports
  • It acts as an economic hub, with significant influence on commerce, tourism, entertainment, tech etc
• Example of an area with low Population density: Siberia, North Asia

  • Only a 1/5 of Russian Population, around 28 million
  • Population Density = (2.8 residents / km2)
  • Has an extreme cold climate, has a January average of -25C
  • Migration is halted due to Ural & Altai mountains
  • Its political affiliation halts people entering the area
• Inter-Relationship between Human Population & Physical Environment: [For Example, Water Supply]

  1. High water supply causes people to enter an area i.e. 95% of Egypt live within 12 miles of River Nile
  2. This influences settlement patterns
  3. Increased population
  4. Levels of consumption increase to unsustainable methods
  5. Overexploitation of resources
  6. Causes acid rain
• Factors Lead to Population Change: Temperature

  • Good = tourism, agriculture, biodiversity, consistent temperatures
  • Bad = Too hot to work, too cold for food, increased hazard risks, extreme weather
• Factors Lead to Population Change: Water

  • Good = Farming, Water Security, If its easily obtainable & reliable
  • Bad = Flooding, Salty, If its difficult & unreliable
• Factors Lead to Population Change: Minerals

  • Good = Sell for $$$ & trade, Unique Selling Point, Easy & Lots of
  • Bad = No minerals, Over extraction bad for planet
• Factors Lead to Population Change: Soils

  • Good = Fertile, Deep, Structural
  • Bad = Thin, High acidity, Crumbly
• How have certain Environmental Constraints been reduced?

  • Pipes
  • Trade
  • Farming
  • Electricity
  • Renewable Energy / Technology
• What dominant Environmental Constraints still influence population?

  • Hazards
  • Extreme Topography
  • Extreme Temperature
  • Extreme Ecosystems
  • Global Warming
• What is Food Security?

  When people have the physical/economic access to affordable & nutritious food
• What is Malnutrition?

  Consuming too little food, leads to loss of body weight
• What is Under-Nutrition?

  Consuming unsuitable amount of energy/proteins which leads to disease
• Statistics on Undernourishment/Malnutrition

  • From 2019 -> 2022, 150 million increase of undernourished people
  • Greatest progress in Caribbean & Latin America
  • 63 countries made millennium target
  • Worldwide obesity doubled since 1980
  • Food Waste = 1/3 of all calories
  • Arab Spring Riots in 30 countries
  • 50 million child wasting
  • 150 million child stunting
• What is the Double-Burden of Nutrition?

  • Countries often are affected by both malnutrition & undernutrition, often due to deficiencies in food security/availability
  • Its a disease of lifestyle - non-communicable
  • HICs often have food causing obesity & heart disease
• Global Patterns in Food Shortage:

  • Mostly Sub-Saharan Africa due to poverty, rural (subsistence farming)
  • Examples of >35% = Eritrea, North Korea, Haiti
  • Occurs when land is not viable for agriculture, climate change is exponentially increasing
• What is Intensive Farming?

  Large Inputs of labour/money relative to the size of farmland. Aims to produce as many positive outputs as possible
• What is Arable Farming vs Pastoral Farming vs Mixed Farming?

  1. Arable Farming: Involves growing Crops
  2. Pastoral Farming: Involves producing Livestock
  3. Mixed Farming: Both
• What is Commercial Farming?

  Farming that focuses on producing agricultural products for profit rather than subsistence
• What is Subsistence Farming?

  Where Sufficient food is provided for the farmers immediate family & their community
• What is Agribusiness?

  Involves large corporate organisation of farming. Farms are run for profit maximisation & Economies of Scale
• What is Extensive Farming?

  Small inputs of labour/money in relation to the size of farmland
• What are Cash Crops?

  Crops grown for sale rather than personal use
• What are the Positives of Cash Crops?

  • Provide economic benefits for LICS - Vietnam is 2nd biggest coffee producer, 500,000 hectares of plantations, & 500,000 jobs (2% of workforce). Provided $2 billion annual export value
• What are the Negatives of Cash Crops?

  • Bad for environment - deforested 74k hectares of rainforest in Pac Lac Province. caused erosion of topsoil, reduction of biodiversity, extinction of the Javan Rhino
  • Creates monoculture - 1 disease wipes out everyone, i.e. MLND wiping out maize crops in Kenya. Puts farmers in 'poverty traps' where they have to sell necessities to survive = risky
  • Monoculture = changing price demands, i.e. Edwina Curry and salmonella gate caused issues for chicken providers i.e. Eastern Europe
• Ways to increase food security:

  • Jamie Oliver healthy school meals = promotes healthy eating & standardises nutritious food
  • Diversify = use local farmers & international exports
  • Research to know where there are inequalities i.e. between Western Tanzania (Lakes with malaria) & Eastern (developed)
  • Target demographics e.g. obesity rates in USA are 1/5 population but especially in Southern States & Black Populations
• Describe the distribution of Semi-Arid climates?

  • 15 N & S of the Equator, fringes of Sahara
  • Simpson Desert caused by Continentality & Gobi Desert caused by Rain Shadow Effect
• Describe the distribution of Mediterranean climates?

  • West Coasts e.g. Santiago, Chile and South Europe
  • 30-40 N & S of Equator.
• Mediterranean Climate Type: Location

  • Found mostly on the Western Side of continents due to upwelling (when nutrient rich, cold water rises up & gets heated by parallel prevailing winds)
  • Occurs in North California due to Santa Ana Winds
  • On 2.2% of land but accounts for 16% of biodiversity
• Mediterranean Climate Type: Characteristics

  • Temperature: Around 20C with diurnal temperature range of 15C
  • Rainfall: Around 500mm
  • Cool, rainy winters & hot, dry summers
  • Types of common vegetation: Small & drought-resistant (chapparal vegetation), such as citrus fruits, seaweed, figs etc
• Mediterranean Climate Type: Farming Systems

  • Intensive Viticulture (Wine) - California produces 90% of American Wine
  • Aquaculture (Kelp & Fish) - California earned $200 million in 2020
  • Has long growing seasons & upwelling, which causes nutrient rich seas
  • ISSUES:

  1. Invasive Species - European Black Mustard in California Hills
  2. Wildfires - longer dry season (semi-arid conditions) & shifted climate belt
  3. 40% of mediterranean land has been destroyed to build cities or agricultural land
• Mediterranean Climate Type: Changes over Time

  • Climate change will intensify extreme weather & decrease winter rain, so aquifers aren't replenished
  • Population Increase from 150 million -> 700 by 2100
  • Exotic Invasive Plants (European Black Mustard overwhelms California Hills)
  • Global Warming may increase dry season & intensive rainfall = longer growing season for wine
  • Viticulture provides 325k Jobs in California
  • Tourism is a huge industry for LIC/NEE (Santiago, Chile or South Europe)
• Semi-Arid Climate Type: Location

  • Found mostly on the fringes of Deserts (Arid or Hyper-Arid)
  • Cold, semi-arid environments often found at higher latitudes
  • Examples = Australian Outback
• Semi-Arid Climate Type: Characteristics

  • Temperature: Hot Semi-Arid = 18C mean
  • Rainfall: 250mm - 500 per year
  • Distinct Dry & Wet Seasons
  • Vegetation is 'zone of Transition' = Savannah, Acacia, Shrubs etc
  • Wildfires in dry season causes vegetation to have ephemeral adaptations
• Semi-Arid Climate Type: Farming Systems

  • Pastoral Farming mainly - either Sedimentary or Nomadic
  • Soil is not appropriate for vegetation, suits nomadic lifestyle
  • ISSUES:

  1. Less than 6% of crops irrigated
  2. Food insecurity in the Sahel Region
  3. Desertification (already affected 36 million km2)
  4. Overcultivation / Overgrazing causes ^^
  5. Reduction of Soil Quality or Structure
• Semi-Arid Climate Type: Changes over Time

  • Population Growth of x3.4 in 45 years, increases resource demand
  • Global Warming intensifies Hazards & Desertification
  • Drip Irrigation, conserves water whilst increasing yield 400% & is an appropriate technology
  • 'Green Climate Fund' 2010 to benefit LICs adapt to climate change
  • Great Green Wall utilises GIS data
  • 12k educated on conservation in Kenya
• What are zonal soils?

  • Soils that have been forming for long periods of time under the influence of climate & vegetation
  • They have clear divisions between horizons and well-defined features
  • Consist of rock, organic matter, water, & air
• Soil Horizons:

  • O = Organic Layer. Uppermost layer made of decomposed animals & plants. Intense biological activity
  • A = Topsoil. Leached minerals with high content of organic matter
  • B = Zone of accumulation, of fine minerals
  • C = Partly weathered rock & rock fragments
  • R = Hard bedrock

  
• Characteristics of Podsol Soil:

  • Around 1m deep
  • High acidity (low pH)
  • Low levels of nutrients
  • Clearly defined horizons
  • Dark A & O horizons (humus layers - high amounts of decay)
  • Hardpan layer in B/C horizon due to acidity mixing with oxides, which waterlogs the soil