Fresh Water Studies:
Water
Quality & Living Organisms
Part 1:
Biotic Indicators
Tuckahoe Swamp
Aquarium
Types of
aquatic
habitats
River/Stream
Swamp
Aquarium
Tap water
(drinking)
Trout? Dragonflies?
Spirogyra (algae)?
Minnows?
E. coli (bacteria)?
Best Quality for life
Abiotic Factors
Abiotic Factors
•
“abiotic”- without life
Refers to those environmental
factors that are not alive, the
non-living components of the
environment.
Abiotic Factors
1. Temperature
Abiotic Factors
Factors that Affect Water Temperature
Air Temperature
exposure to
sunlight
exposure to
sunlight
Low
Medium
Amount of shade
Low
High
Which water will be warmer?
Soil erosion increasing turbidity
4. Thermal pollution from human activities
Temperature increases from human activities
Photo: Dominion Virginia Power – North Anna Power Station
Confluence of streams
Photo: Virginia Academy of Science
Abiotic Factors
1. Temperature
Effects of Water Temperature
• Solubility of dissolved oxygen
• Rate of plant growth
• Metabolic rate of organisms
• Resistance in organisms
Abiotic Factors
1. Temperature
2. Oxygen (Dissolved)
Abiotic Factors
1. Temperature
2. Oxygen (Dissolved)
Where does the oxygen come from?
How does it get into the water?
Diffusion from atmosphere
Aeration as water moves over rocks and debris
Aeration from wind and waves
AND
Photo: NOAA
Photosynthesis from aquatic plants
Factors that affect DO levels are:
• Temperature of water
• Decaying plants in the water
• Flow Rate
• Human activity
• Altitude and atmospheric pressure
Abiotic Factors
1. Temperature
2. Oxygen (Dissolved)
3. pH
What is pH?
0-7 water is acidic (more H+ ions, less OH- ions)
7 water is neutral (equal number of H+ and OH- ions)
7-14 water is basic (less H+ ions, more OH- ions)
What is the optimum freshwater pH?
Rainfall: 5 – 6.5
Most freshwater systems: 7 - 8
Most aquatic organisms: 6.5 – 8.2
Abiotic Factors
1.
2.
3.
4.
Temperature
Oxygen (Dissolved)
pH
Turbidity
Turbidity- An optical property of water
based on the amount of light reflected
by suspended particles. –USEPA, 1999
Secchi Disk
Abiotic Factors
1.
2.
3.
4.
5.
Temperature
Oxygen (Dissolved)
pH
Turbidity
Total Dissolved Solids (TDS) from
hard water, fertilizer, urban runoff,
acid rain, tidal mixing
Abiotic Factors
1.
2.
3.
4.
5.
6.
Temperature
Oxygen (Dissolved)
pH
Turbidity
TDS
Stream Flow
Stream Flow
The volume of water that moves through
a specific point in a stream during a
given period of time.
Stream Flow
The volume of water that moves through
a specific point in a stream during a
given period of time.
Factors influencing water
speed.
Factors influencing water
volume
1. Depth of the water channel
1. Weather or climate
2. Width of the water channel
2. Seasonal changes
3. Roughness of the stream
bottom
3. Merging tributaries
4. Slope or incline of the
surrounding terrain.
4. Human impact
Conclusion
• Water quality is determined by conducting physical and chemical
measurements of the ABIOTIC factors of a freshwater environment.
• ABIOTIC factors include temperature, dissolved oxygen, pH,
turbidity, total dissolved solids, and stream flow.
• ABIOTIC factors determine the BIOTIC factors (what can live) in the
freshwater environment.
Photo credits-used with Permission
1.
R.B.Elder
2.
M.B. Elder
3.
M.B. Elder
4 - 9*
10.
M.B. Elder
11.
Dominion Virginia Power
-North Anna Power Station
12.
Virginia Academy of Science
13 - 15 *
16.
National Oceanographic
& Atmospheric
Administration
(NOAA)
17 & 18 M.B. Elder
19 - 22 *
23 & 24 M.B. Elder
25 - 30 *
* Background slide - R.B. Elder
rights reserved)
(all