8.E.1 Understand the hydrosphere and the impact of humans on local systems and the effects of the hydrosphere on humans. 8.E.1.3 Predict the safety and potability of water supplies in North Carolina based on physical and biological factors, including: Temperature, Dissolved oxygen, pH, Nitrates and phosphates, Turbidity, Bio-indicators 8.E.1.4 Conclude that the good health of humans requires: Monitoring of the hydrosphere, Water quality standards, Methods of water treatment, Maintaining safe water quality, Stewardship

Two Types of Pollution One is easier to control than the other!

Types of Water Pollution The Environmental Protection Agency (EPA) sets the guidelines for what qualifies as a healthy body of water. Potable – Describes water that is safe to drink https://www.youtube.com/watch?v=Z3IeS0gFH1M https://www.youtube.com/watch?v=8h2mhn35DhM

Two Types of Pollution One is easier to control than the other! Point Source Pollution Non Point Source Pollution

Two Types of Pollution One is easier to control than the other Point Source Pollution any single identifiable source of pollution from which pollutants are discharged, such as a pipe, ditch, ship or factory smokestack. Factories and sewage treatment plants are two common types of point sources.

Nonpoint Source Pollution Pollution discharged over a wide land area, not from one specific location. Non-point source pollution is contamination that occurs when rainwater, snowmelt, or irrigation washes off plowed fields, city streets, or suburban backyards. As this runoff moves across the land surface, it picks up soil particles and pollutants, such as nutrients and pesticides.

Identify each of the following as point source or nonpoint source pollution: 2. 3. 4. 5. 6. Runoff

103 Freshwater Y Chart Physical Biological Chemical

Physical variables include temperature, turbidity. The health of a water system is determined by the balance between physical, chemical, and biological variables. Physical variables include temperature, turbidity.

Chemical variables include dissolved oxygen and other gases, pH, nitrates and phosphates. Both natural and man-made forces are constantly changing these variables.

Biological variables are living organisms. Bio-indicators are living organisms that require specific conditions in order to survive. Their presence in waters, or lack of presence, is an indicator of the health of a water system.

Water Quality Indicator Notes Turbidity Description: Murkiness of water due to suspended particles Levels: Ideal = 1NTU High = 5o NTU+

Turbidity Causes: Erosion from construction urban run off disturbance of stream beds from bottom feeders/livestock increased algal growth septic system leaks decaying plant matter flooding

Turbidity Increase temperature Decrease in DO Results: Increase temperature Decrease in DO Clogs gills in some aquatic organisms

Temperature Amount of kinetic energy Description: Levels: Low: cannot be tolerated below 00C High: only rough fish can tolerate temperatures above 350C

Temperature Causes: Loss of shade from removal of vegetation Thermal Pollution: industry discharge seasonal temp changes Results: Decreased levels of DO increased bacterial levels, increased algae growth

pH Description: How acidic the water is Levels: 06 is acidic 7 is neutral 814 is basic Surface Freshwater: 6.0 9.0

pH Cause: Acid rain minerals in soils Results: Death of sensitive bio-indicators Death or damage to plants

What is pH? 0-6 water is acidic 7 water is neutral 8-14 water is basic Slide 20. Abiotic Factors-pH pH is usually a number on a unitless scale, from 0 – 14. 0 being most acidic and 14 being most basic. A pH of 7 is considered neutral, with equal amounts of hydrogen and hydroxide ions. 0-6 water is acidic 7 water is neutral 8-14 water is basic

What is the optimum freshwater pH? Slide 21. Abiotic Factors-pH The pH of rain depends on the amount of industrialization in the rainfall area. Air pollution from emissions from industry often produce carbonic, sulfuric and nitric acids which lower the pH. The water which drains a limestone area high in bicarbonates can raise the pH of the water as high as 8.5. Aquatic organisms are VERY sensitive to changes in pH. Rainfall: 5 – 6.5 Most freshwater systems: 7 - 8 Most aquatic organisms: 6.5 – 8.2

Dissolved Oxygen Description: Oxygen gas dissolved in water O2 enters water through photosynthesis and churning water Levels: 4-5 ppm optimal to support life  

Dissolved Oxygen Cause: Increased Temp Decaying plant material Effect: Less diversity of bio-indicators fish-kills

Nitrates & Phosphates Description: Excess nutrients Level: Nitrates above 1 ppm unhealthy Phosphates above .003 ppm unhealthy

Nitrates & Phosphates Cause: Fertilizer run off Animal waste Leaking septic systems Manure pits (hog farms, etc) Average Level: Eutrophication – overgrowth of algae (pond scum) Low DO

EUTROPHICATION FLOW CHART Excess Nutrients  Algal Bloom (pond scum)  darkness below surface  photosynthesis stops  decomposers & other organisms use up oxygen  DEATH (gradual buildup of dying plant matter the pond becomes a meadow)

Bio-Indicators Description: Macro-invertebrates living in water that are sensitive to pollution Level: Large numbers and diversity

Bio-Indicators Cause: Increased levels of pollution Result: Less diversity of organisms Fewer organisms

Hardness Description: The amount of calcium and magnesium in the water These elements are needed for plant walls and shells/skeletons of aquatic organisms Levels: Hard water has high levels of Ca & Mg Soft water has low levels of Ca & Mg

Hardness Cause: Water dissolves these minerals out of soil and rocks. Ground water tends to be harder than surface water Result: Low levels of Ca support only a small amount of plant and animal life High levels can contribute to algae problems