challenges in the human environment

• what is a resource?

  a stock or supply of something that has value or purpose
• why is food globally significant?

  a poor diet can result in diseases and illnesses
• why is water globally significant?

  essential for drinking, vital for crops and can be used to produce energy
• why is energy globally significant?

  it is needed for light heat and power
• what global inequalities exist with food?

  malnutrition affects 2 billion and over 1 billion people do not get enough calories
• what global inequalities exist with energy?

  richer countries consume more energy than poorer countries , the middle east is a major oil supplier yet its consumption is low
• what global inequalities exist with water?

  variations in climate and rainfall affect supply , LICs have a water shortage and use the most water in agriculture
• why does the UK import 40% of its food?

  there is availability of cheaper food from abroad, there is a demand for more exotic foods and seasonal produce all year round and the UK's climate is unsuitable for the production of some foods
• why is it a bad idea to import food?

  it adds to our carbon footprint and conflict with a country which we import food from could mean that we would not have any food
• the north and west of the UK have a water surplus where supply exceeds demand
• the south and the east have a water deficit , where demand exceeds supply
• the environment agency manages water quality by: filtering water to remove sediment, purifying water by adding chlorine , imposing strict regulations
• water transfer: there is a growing need to increase water transfer to meet demand , there is opposition because of the effect on land and wildlife , high costs and the greenhouse gases released by pumping water over long distances
• what are the demands for water in the UK?

  almost 50% of the UK's supply is used domestically. Demand for water is increasing because of a rapidly growing population , more houses and an increase in the use of water intensive domestic appliances
• energy consumption has fallen in the UK in recent years , mainly due to the decline of heavy industry and energy conservation
• why has the UK's energy mix changed?

  about 75% of the UK's known oil and gas reserves have been used up , coal consumption has declined because of concerns about greenhouse gas emissions
• why are fossil fuels likely to still remain important?

  the UK's remaining reserves will provide energy for several decades , coal imports are cheap , shale gas deposits may be exploited in the future
• why is water consumption increasing?

  water is required for increasing energy production , increase in population so more water is needed , economic development results in higher consumption, changes in lifestyle and eating habits - more irrigation to produce food
• how does geology affect water availability?

  permeable rocks allow water to infiltrate which builds up groundwater supplies
• how does overabstraction lead to a lower water table?

  pumping water out of the ground quicker than it is replaced by rainfall causes wells to dry up and lowers water tables
• how does poverty affect water availability?

  Many poorer countries lack mains water or only have access to shared water supplies so their is lower availability
• how polluted is the river Ganges?

  over 1 billion litres of raw sewage enter the river Ganges daily , factories discharge 260 million litres of untreated waste water into the river each day
• advantages of dams

  control river flow by storing water in reservoirs , enables it to be transported and used for irrigation, used to prevent flooding
• disadvantages of dams

  expensive, can lead to the displacement of large numbers of people, may reduce the flow of the river downstream, in hot regions reservoirs can lose a lot of water through evaporation
• what is the Lesotho highland water project?

  huge water transfer scheme aiming to help solve the water shortage in South Africa , 40% of the Segu River in the Lesotho will eventually be transferred to the River Vaal in South Africa , involves the construction of dams, roads, pipelines , reservoirs
• advantages of the scheme to Lesotho

  provides 75% of lesothos GDP , sanitation coverage will increase from 15 - 20%
• disadvantages of the scheme for Lesotho

  building the first 2 dams displaced 300,000 people , corruption has prevented money reaching those affected by the construction , destruction of a unique wetland ecosystem
• advantages for south africa

  provides water to an area with regular droughts, provides safe water to an extra 10% of the population
• disadvantages for South Africa

  costs likely to reach 4 billion US dollars , 40% of water lost through leakages