ESS Topic 4

• Water keeps us alive, sculpts the land, and is at the core of Earth's functioning
• Water removes wastes and dilutes them, and is part of the water cycle or hydrological cycle
• Renewable resource


  Can be used at a rate that is replenishable
• Non-renewable resource


  Cannot be used sustainably, using them reduces the natural capital's ability to regenerate
• Oceans can be considered a non-renewable resource, whereas the atmosphere (water particles) can be considered renewable
• Turnover time


  The time taken for water to completely cycle in the water cycle and return to a point
• Only 3% of Earth's water is freshwater, and around 70% of that is in ice caps or glaciers, so unavailable for use
• Water scarcity is a problem, with rivers running dry, lakes and seas shrinking, and water bodies being over-pumped at an unsustainable rate
• The water cycle


  1. Evaporation

  2. Condensation

  3. Runoff

  4. Precipitation
• Humans can impact the hydrological cycle through


  • Agriculture (pesticides and fertilizers)
  • Deforestation
  • Climate change
  • Over-pumping of aquifers
• Agriculture uses 70% of withdrawn water, industry uses 20%, and water distribution is uneven worldwide
• Most water withdrawal is done at an unsustainable rate, faster than the environment can withstand and replenish
• Sources of fresh water


  • Lakes
  • Rivers
  • Streams
  • Aquifers
• Aquifers


  Unsustainable non-renewable resource that takes 1,500 years to replenish
• Problems with water systems


  • Water scarcity
  • Water degradation
• Water scarcity


  • Lack of water, increased demand due to growing population, impact of climate change and agricultural practices, over-pumping of aquifers
• Water degradation


  • Contamination with arsenic, salts, and other minerals, use of fertilizers and pesticides causing eutrophication, releasing pollutants directly into waterways, salinization of topsoils due to climate change
• Solutions to water problems


  • Efficient domestic use
  • Rainwater recycling and harvesting
  • Drip irrigation and watering at night
  • Organic farming methods
  • Removing pollutants from wastewater plants
  • Legislation and regulation
• Eutrophication


  1. Excess input of nutrients (phosphates and nitrates) from fertilizers

  2. Excess growth of plants and phytoplankton

  3. Increased turbidity blocking light to submerged plants

  4. Accumulation of dead organic matter

  5. Decomposers using up oxygen leading to hypoxic waters

  6. Decreased biodiversity
• Solar power is generated by converting sunlight into electricity using photovoltaic cells or concentrated solar panels.
• Wind power is generated by using turbines that convert kinetic energy from moving air into mechanical energy.
• Secondary succession happens in areas where there is already soil, like after a forest fire.
• The main types of renewable energy are wind, solar, hydroelectricity, geothermal, tidal, wave, biomass, and biofuels.
• The main types of renewable energy are solar, wind, hydroelectricity, geothermal, tidal, wave, biomass, and biofuels.
• Renewables have the potential to replace fossil fuels as they can be replenished naturally over time.
• Pioneer species are the first organisms to colonize a barren environment during primary succession.
• Primary succession occurs in an area where no soil is present, such as after a volcanic eruption.
• Renewables have the potential to replace fossil fuels as they can be replenished naturally over time.