Aquatic Ecology

• ecology -> branch of biology that studies the relations of organisms to one another and to their physical surroundings
• Aquatic -> relating to water
• Aquatic Ecology -> is the study of ecology of water
• water is the number one substance on earth
• aquatic ecology includes all aquatic enviroments
• Marine Ecology

  • study of ecology in marine (ocean) environments
• Freshwater Ecology

  • study of ecology in freshwater environments
• What five things comprise freshwater?

  lakes, rivers, wetlands, groundwater, and glaciers
• glaciers make up the majority of freshwater
• lakes, rivers, and wetlands comprise 0.4% of freshwater
• Lake

  • large body of water surrounded by land
  • do not have consistent directional flow
  • size is subjective
• River

  • body of flowing water in a defined channel
  • water primarily moves in one direction (typically downstream)
• Wetlands

  • areas where water covers the soil, or is present either at or near the surface of the soil
  • water does not always have to be at the surface
• are lakes and rivers wetlands?

  yes
• Lakes, rivers and wetlands make up the surface waters
• the physical environment dictates the biological environment
• freshwater has the highest diversity of any ecosystem on earth
• freshwater is an essential resource to human society and terrestrial life
• freshwater is the most threatened ecosystem on earth
• water use can be consumptive or non-consumptive
• consumptive -> water lost -> cant be used again once used
• non-consumptive -> water is still available for future use (water dam)
• water reservoir -> has huge impact on water availability as it increases surface area which in turn increases evaporation (water loss)
• example of consumptive use?

  irrigation and evaporation
• What are the three main purposes of water use?

  domestic, agriculture, and industrial purposes
• Domestic Water Use

  • washing, drinking, watering
  • smallest % of water used in developed countries
  • ~8% of global water consumption
• Industrial Water Use

  • fabricating, washing, diluting, cooling
  • fairly large in canada
  • smallest % of water use in the most developed countries
  • 23% of global water consumption
• Agricultural Water Use

  • irrigation, livestock watering
  • biggest use across globe
  • 69% of global water consumption
• the water cycle replenishes freshwater supplies
• Steps to the water cycle

  1. evaporation of salty ocean water
  2. precipitation of freshwater
  3. runoff of freshwater back to oceans
• Runoff = water yeild
• runoff Is typically considered the portion of water that is renewable
• there are a lot of places around the world that do not have aquatic ecosystems because they do not have enough freshwater
• value of water is dependent on quality
• water use may require:

  high or low quality water
• example of high quality water is drinking water
• example of low quality water is power generation
• human activities often impair water quality
• water stress depends on availability and demand in a given area
• renewable freshwater is considered to be runoff portion of hydrologic cycle