Pollution Chapter 13 Water Pollution Types and Sources

Pollution Chapter 13

Water Pollution

Types and Sources of Water Pollution Ø #1 problem - Eroded soils Ø Organic wastes, disease-causing agents Ø Chemicals, nutrients Ø Radioactive stuff, heat

Point and Nonpoint Sources NONPOINT SOURCES Rural homes Cropland Urban streets Animal feedlot Suburban development POINT SOURCES Wastewater treatment plant Factory

Major Problem: Drinking Water Ø 1/2 of world’s people drink polluted water Ø Safe Drinking Water Act Ø EPA: Maximum contaminant levels (municipal, but not rural and private)

Pollution of Surface Water: Streams Ø D. O. , B. O. D. , fecal coliform bacteria count

Pollution of Surface Water: Lakes Ø Cultural eutrophication Ø Slow turnover ØAccumulation of nutrients, excessive plant growth, algae blooms

Case Study: The Great Lakes

Mississippi River Basin Ohio River Missouri River LOUISIANA Mississippi River Depleted Dead Zone Oxygen Gulf of Mexico

Suffocated fish Altered food web Low dissolved oxygen Decreased fish population Thermal Pollution

Groundwater Pollution: Sources Ø Cold temperatures Ø Low flow rates Ø Few bacteria Hazardous waste injection well Coal strip mine runoff Pesticides De-icing road salt Pumping well Waste lagoon Buried gasoline and solvent tank Cesspool septic tank Gasoline station Water pumping well Landfill Accidental spills Sewer ifer aqu Leakage from faulty casing Discharge r ate r w e h uif res Confined aquifer q f a r ed e t n i a f con shw Groundwater e n r U df e flow n nfi o C

Groundwater Pollution Prevention Ø Monitoring aquifers - expensive Ø Leak detection systems Ø Strictly regulating hazardous waste disposal Ø Protecting recharge areas - aquifer classifications

Ocean Pollution: dumping and oil

Oil Spills Ø Sources: offshore wells, tankers, pipelines and storage tanks Ø Effects: death of organisms, loss of animal insulation and buoyancy, smothering Ø Significant economic impacts Ø Short-term cleanup problems - beaches, wildlife Ø Long-term cleanup problem - persistence (decades)

Case Study: Chesapeake Bay Ø Largest US estuary Ø Relatively shallow Ø Slow “flushing” action to Atlantic Ø Major problems with dissolved O 2

Solutions: Preventing and Reducing Surface Water Pollution Nonpoint Sources Ø Reduce runoff Ø Buffer zone vegetation Ø Reduce soil erosion Point Sources Ø Water Pollution Control Act (1972) Ø Clean Water Act (1977) - set effluent standards - secondary treatment

Technological Approach: Septic Systems Ø Require suitable soils and maintenance

Technological Approach: Sewage Treatment Ø Mechanical and biological treatment

Technological Approach: Advanced Sewage Treatment Ø Removes specific pollutants

Technological Approach: Using Wetlands to Treat Sewage

Acid Deposition

Automobiles as a Source NO from cars

Widespread Secondary Air Pollution: Acid Deposition Ø Wet deposition Ø Dry deposition

Acid Deposition in the U. S.

Acid Deposition, Plants, and Soil

Acid Deposition, Plants, and Soil n n n Direct damage to forest tree foliage Erodes protective waxes from leaves, needles Leaches nutrients from leaves

Acid Deposition, Plants, and Soil n n Lowers soil p. H Affects mineral solubility Leach out positively charged ions (K, Mg, Ca) from clay particles Easily flushed away

Acid Deposition, Plants, and Soil n n n Increases concentration of potentially toxic minerals E. g. , aluminum Damages xylem - reduces ability to take in water, nutrients - die from lack of moisture, nutrients

Acid Deposition, Plants, and Soil n n Has resulted in loss of large stands of trees in many different regions around world Canada, New England, Smoky Mountains

Acid Deposition, Plants, and Soil

Acid Deposition, Plants, and Soil n n Nearly 70% of forests in Czech Republic have been destroyed Trees in nearly half of Germany’s Black Forest have been impacted

Acid Deposition, Plants, and Soil n n Switzerland has lost 10% of its forests Increased chance of avalanches

Acid Deposition, Plants, and Soil n Large portions of forests in Norway have been lost, especially in southern regions

Acid Deposition, Plants, and Soil n Correlation between dying forests and thriving ground layer of mosses

Acid Deposition, Plants, and Soil n n n Mosses are acidloving Thick layer holds do much moisture that surface soils become saturated Feeder roots, tree die from lack of oxygen (drown)

Acid Deposition, Plants, and Soil n n Mosses also may kill mycorrhizal fungi Reduce uptake of nutrients

Acid Deposition, Plants, and Soil n n Dense layer of mosses may further acidify water passing through them into soil Dissolve more toxic trace metals, leach more soil nutrients

Acid Deposition, Plants, and Soil n Even if trees somehow manage to survive all these problems, their growth is reduced substantially

Acid Deposition, Plants, and Soil

Acid Deposition, Plants, and Soil n Varying effects on crop productivity, but wide distribution of problem areas

Acid Deposition, Plants, and Soil n n Some evidence for direct damage Potatoes in Canada damage to foliage, potential uptake of toxins

Acid Deposition, Plants, and Soil n Coffee plants have shown damage to foliage in some areas

Acid Deposition, Plants, and Soil n Although much evidence points toward harmful effects from acid rain, some studies show the opposite

Acid Deposition, Plants, and Soil n n Helpful to crops where soil nutrients may be very low - nitrogenlimited Acidification may release nutrients, allow for greater uptake

Acid Deposition, Plants, and Soil n n Some evidence where crops show now effect of acid deposition, either negative or positive Balance each other out

Acid Deposition and Aquatic Systems Ø Fish, Invertebrates decline (<5. 0) Ø Undesirable species

Acid Deposition and Aquatic Systems n n Adirondacks - 25% of lakes too acidic for fish, 20% threatened EPA: 15, 000 U. S. lakes acidified or threatened

Acid Deposition and Aquatic Systems n 1/3 of Florida lakes acidic enough to cause harm to aquatic life

Acid Deposition and Aquatic Systems n 20, 000 lakes in Sweden are too acidic for fish

Acid Deposition and Aquatic Systems n n Salmon runs in most Norway rivers have been eliminated No egg production

Acid Deposition and Aquatic Systems n 20 famous salmonfishing rivers in Nova Scotia have lost or are near to losing the fish

Acid Deposition and Aquatic Systems n Half of Quebec’s 48, 000 lakes were acidified by year 2000, and more are becoming that way

Acid Deposition and Aquatic Systems n n During most seasons, acids are not direct problem, but they mobilize toxic metals: aluminum, lead, mercury Aluminum irritates gills of fish, causes mucus buildup, death from asphyxiation

Acid Deposition and Aquatic Systems n n Major problem season: snowmelt First 30% of meltwater contains virtually all the acid p. H 3. 0 -3. 5 Toxic to eggs, fish fry, adult fish

Global Carbon Cycle Human effects: fossil fuel combustion, cutting and burning of trees

Global Carbon Cycle

Global Carbon Cycle n Increasing atmospheric CO 2 has brought about a rise in global temperature

Greenhouse Effect n n CO 2 acts like glass in a global greenhouse Slows escape of infrared radiation from earth’s surface

Greenhouse Effect n n Many other gases are far more effective at trapping heat Methane, CFCs, nitrous oxide (N 2 O) 20 -270 X as effective CO 2 responsible for 2/3 of increase in greenhouse effect

Greenhouse Effect n n n CO 2 concentrations increased 21. 5% from 1870 -1990 Increasing consumption of fossil fuels, deforestation Doubling of CO 2 concentrations may occur with continued fossil fuel use over 50 -100 years

Greenhouse Effect n n CO 2 doubling may increase average global temperature by 2 -5°C Global temps have increased 0. 8°C over last century, 0. 6° of that in last 30 years

Major Climate Changes n n Worldwide change in patterns of precipitation, storms, winds, ocean currents Each 1°C increase pushes climatic zones 90 mi N in N. hemisphere

Major Climate Changes n n Variable effects worldwide, but greatest changes between 40 and 70°N, in N. Amer. and Eurasia Caused by both warmer temps and increased CO 2 (greater forest productivity)

Major Climate Changes n Polar ice sheets and glaciers have been melting, and changes would escalate

Major Climate Changes n n n Sea levels would rise due to melting ice, expansion of warming water 4°C increase would cause 0. 5 -1. 5 m rise worldwide Flood coastal wetlands, low-lying cities, agricultural lands

Major Climate Changes n n Frequency, intensity of weather extremes would increase Heat waves, drought, hurricanes

Major Climate Changes n n Speed up decay of organic matter Further increase CO 2 concentrations in atmosphere

Major Climate Changes n Warmer climates spreading northward would bring insect-borne diseases, more pests into areas currently protected by cold temperatures

Major Climate Changes n n Growth rates of many tree species would be lowered Ranges would have to shift northward At rate up to 10 X greater than they’ve ever done in the past Birch, sugar maple

Major Climate Changes n n Stress from pests, disease microorganisms would increase Adapt faster than tress to changing environments

Major Climate Changes n n n More frequent fires Forest and grassland Increased disturbance: decreased diversity?

Major Climate Changes n n n But are rising CO 2 concentrations really a concern? 3 -4 X higher 250 million years ago Regular cycling over past 400, 000 years

Major Climate Changes n n Rising global temperatures? 30 years ago there were signs that we were entering glacial cooling