Unit C - Section 2 Flashcards
5 uses of water
- human drinking water
- recreation
- livestock drinking water
- irrigation
- protection of aquatic life
Microbiological indicators
Microscopic organisms such as bacteria can cause serious health issues.
Aquatic invertebrates
Water with a large number of harmful bacteria that causes illness
What indicates unsafe water
Water that shows affect of pollution
Invertebrates
Animals without backbones (insects, crustaceans, worms and mollusks)
What are invertebrates used for
Used for monitoring because different invertebrates prefer different living conditions
What can affect these types of organisms
Water temperature and pH
Aquatic environment
If the pH of the wafer is below 5.0 you will not find many fish there
Why does the diversity decrease
Because it’s acidity that increases and its dissolved oxygen decreseases
What is monitored in water quality
- dissolved oxygen
- acidity
- heavy metals
- plant nutrients (nitrogen and phosphorus)
- pesticides
- salts such as sodium chloride
Ppm
Parts per million or milligrams per litre
Ppb
Parts per billion
How many times do you move the decimal if it’s ppm
You move the decimal 6 times to the right
How many times do you move the decimal if it’s ppb
You move the decimal 9 times to the right
Why is dissolved oxygen essential
For the health if aquatic life such as fish, insects and micro organisms
What does the level of dissolved oxygen depend on
- temperature
- turbulence due to wind or the speed of moving water
- the amount of photosynthesis by plants and algae in the water
- the number of organisms using up the oxygen
What do the white dots represent
Number of bacteria
What does a clean lake have
Contains a variety of organisms. (Fish, mayfly nymph, stonefly nymph, midge larvae and worms).
What does the second stage have
Added plant nutrients from treated sewage or runoff from fields causes more algae. Fewer fish can live in these conditions
Third stage
Some plants die. The population of bacteria increases. The lake is no longer a place where fish and insects can live in
Acidic deposition
Major problem because the soil and water lack natural bases to neutralize acidic precipitation
What is Spring acid shock
When the snow melts the acid meltwater flows into aquatic systems.
What concentration does this create
Of acid that can lower pH of the water in a pond, lake or river for a short time
Why is Spring acid shock dangerous
Affects the eggs of aquatic organisms
Toxiticy
Describes how poisonous a substance is
What do toxins produce
Produce serious health or death
What is LD50
Used to compare toxins
What does LD stand for
Lethal dose
What does the 50 represent
50%