1. Water pollution
Chapter 11

2. water pollution
Any contamination of water that lessens its value to humans and other species, aquatic and non aquatic. Classification: By the source By the chemical

3. Pollution routes Surface water Ground Water
Bodies of water that have direct contact with the atmosphere
Ground Water
Water found in the ground, either in saturation or deep deposits

4. Point source Well defined location (a point)
Sewage treatment or factory/plant waste
Discharges straight into surface or ground water

5. Nonpoint source Do not come from distinct points
Comes from farmland area where pesticides and artificial fertilizer are used
Chemicals can drain/leach into ground water or into surface water

6. Chemical type classifications
Sediment
Inorganic nutrients
Thermal pollution
Disease-producing microorganisms
Toxic organic chemicals
Heavy metals
Oxygen-demanding organic wastes

7. sedimentation
Sand, silt, and clay eroded from soils and washed from roadways
0.9 billion metric tons of soil are washed into our aquatic systems in the US annually
The Mississippi River carries 210 million metric tons into the Gulf of Mexico each year

8. Where does sediment come from
Natural stream bank erosion
Wind erosion
Farmland
Construction sites
Timber harvesting
Strip Mining

10. Harmful effects of soil erosion
Sediment will damage turbines in hydroelectric plants
Harbors and river channels must be dredged periodically
Soil can often times carry chemicals and pesticides
Suspended solids block sunlight which kill algae
Reduces oxygen
Kills bacteria

11. Contour farming
Plowing, seeding, cultivating and harvesting at a right angle to the direction of the slopes
Jefferson practiced this method
Most farming years ago went up and down slopes

13. Strip cropping
Growing crops that different types of tillage (one row crop alternated with one cover crop)
Crops are sown along contours or across the prevailing wind direction to decrease soil erosion by water & wind
Example:
Row crop (corn, potatoes, tobacco)
Cover crop (hay, soybeans)

15. Terracing Practiced by Incas and Peru and by the ancient Chinese
Limited land space due to populations
Tilled into the mountains
Allows the whole surface to be farmed
Benched terraces can allow water to stay on a surface
Rice fields

17. Gully reclamation
Gullies are erosion channels too large to be erased by ordinary farming operations
They are active when their walls are free of vegetation
Must be plowed and seeded at first notice

18. Conservation tillage
Plowing with different types of blades to reduce soil erosion
No till practices
Leave at least 30% of the crop residue
Farmers are encourage to practice this method