Freshwater Flashcards
(90 cards)
What does ‘potable’ mean?
Used for consumption
Define a lake.
Inland basin of fresh water, with a surface area of more than 1 hectare
What is a watershed?
Area of land where all water from precipitation drains to
Who is a limnologist?
Scientist that studies lakes
What are oligotrophic waters?
Lakes and ponds: low nutrient, high clarity, high oxygen conditions
What are eutrophic waters?
Lakes and ponds: high nutrient, low clarity, low oxygen conditions
What is freshwater defined as?
Less than 500mg salt per liter
What percentage of water on Earth is freshwater?
2.5%
Where is most freshwater found?
Most locked away in glaciers, groundwater; 1% on surface
What is the primary component of Earth’s water?
Ocean makes up 97.5%
What is the percentage of water usage in Canada for industry?
56%
What is the percentage of water usage in Canada for domestic purposes?
24%
What is the percentage of water usage in Canada for agriculture?
20%
What percentage of water does India use for agriculture?
87%
What is the global percentage of water usage for agriculture?
69%
What is the global percentage of water usage for industrial purposes?
23%
What is the global percentage of water usage for domestic purposes?
7%
How is water clarity measured?
Using a Secchi disk
What is thermal stratification in lakes?
Lakes divide into different layers of temperature and density
Name the three layers of lake stratification.
- Epilimnion: warmest, high O2
- Metalimnion: middle, thermocline
- Hypolimnion: cold dense water around 4C, often low to no oxygen
What is a thermocline?
Greatest temperature and density difference in a lake
What does anoxic mean?
Low to no oxygen
What is an amictic lake?
Permanent ice cover, no mixing
What is a monomictic lake?
Mixes once a year