Water quality notes

General Types of General Types of Water PollutionWater Pollution

Water Quality NotesWater Quality Notes

Chapter Overview QuestionsChapter Overview Questions What pollutes water, where do these What pollutes water, where do these

pollutants come from, and what effects pollutants come from, and what effects do they have?do they have?

What are the major water pollution What are the major water pollution problems in streams and lakes?problems in streams and lakes?

What causes groundwater pollution, What causes groundwater pollution, and how can it be prevented?and how can it be prevented?

What are the major water pollution What are the major water pollution problems affecting oceans?problems affecting oceans?

Chapter Overview Questions Chapter Overview Questions (cont’d)(cont’d)

How can we prevent and reduce How can we prevent and reduce surface water pollution?surface water pollution?

How safe is drinking water, and how How safe is drinking water, and how can it be made safer?can it be made safer?

Oil Spill Simulation LabOil Spill Simulation Lab

Water Treatment LabWater Treatment Lab

Water WebquestWater Webquest

Milk LabMilk Lab

Sewage CompetitionSewage Competition

Core Case Study: Using Nature to Core Case Study: Using Nature to Purify SewagePurify Sewage

Ecological Ecological wastewater wastewater purification by a purification by a l iving machineliving machine .. Uses the sun and a Uses the sun and a

series of tanks series of tanks containing plants, containing plants, snails, zooplankton, snails, zooplankton, crayfish, and fish (that crayfish, and fish (that can be eaten or sold can be eaten or sold for bait).for bait).

Figure 21-1Figure 21-1

DefinitionDefinition Excessive amounts of suspended Excessive amounts of suspended

soil particles that eventually settle soil particles that eventually settle out and accumulate on the bottom out and accumulate on the bottom of a body of water.of a body of water.

Sediment PollutionSediment Pollution

CausesCauses

Erosion of agricultural lands, forest Erosion of agricultural lands, forest soils exposed by logging, degraded soils exposed by logging, degraded stream banks, overgrazed stream banks, overgrazed rangelands, strip mines, and rangelands, strip mines, and construction.construction.

Environmental EffectsEnvironmental Effects Reduces light Reduces light

penetration, penetration, covering covering aquatic aquatic organisms, organisms, bringing bringing insoluble toxic insoluble toxic pollutants into pollutants into the water, and the water, and filling in filling in waterways. waterways.

Health EffectsHealth Effects Sediments adversely affect water Sediments adversely affect water

quality by carrying toxic chemicals. quality by carrying toxic chemicals. The sediment particles provide surface The sediment particles provide surface

area to which some insoluble, toxic area to which some insoluble, toxic compounds adhere; when the compounds adhere; when the sediments enter the water, so do toxic sediments enter the water, so do toxic chemicals. chemicals.

Disease-causing agents can also be Disease-causing agents can also be transported into water via sediments.transported into water via sediments.

SewageSewage

CausesCauses Release of Release of

waste water waste water from drains or from drains or sewers (toilets, sewers (toilets, washing washing machines, and machines, and showers) and showers) and include human include human wastes, soaps wastes, soaps and detergents.and detergents.

Environmental EffectsEnvironmental Effects

Enrichment – the fertilization of Enrichment – the fertilization of a body of water, caused by the a body of water, caused by the presence of high levels of presence of high levels of plants and algal nutrients like plants and algal nutrients like nitrogen and phosphorusnitrogen and phosphorus

Health EffectsHealth Effects

Oxygen – dissolved oxygen is Oxygen – dissolved oxygen is needed by organisms, like fish, but needed by organisms, like fish, but when sewage enters an aquatic when sewage enters an aquatic ecosystem, the micro-organisms ecosystem, the micro-organisms bloom, leaving less oxygen for the bloom, leaving less oxygen for the fish, etc., and then they diefish, etc., and then they die

Sewage carries disease-Sewage carries disease-causing agents.causing agents.

DefinitionDefinitionInfectious organisms that cause Infectious organisms that cause

disease.disease.

Disease-Causing AgentsDisease-Causing Agents

Environmental EffectsEnvironmental Effects Municipal wastewater contains bacteria, Municipal wastewater contains bacteria,

viruses, protozoa, parasitic worms, and viruses, protozoa, parasitic worms, and other infectious agents that cause human other infectious agents that cause human or animal diseases.or animal diseases.

CausesCausesComes from the wastes of infected Comes from the wastes of infected individuals.individuals.


Typhoid, cholera, bacterial Typhoid, cholera, bacterial dysentery, polio and infectious dysentery, polio and infectious hepatitis are some of the more hepatitis are some of the more common bacteria or viruses that common bacteria or viruses that are transmitted through are transmitted through contaminated food and water.contaminated food and water.

Major Water Pollutants Major Water Pollutants and Their Effectsand Their Effects

Water quality and dissolved oxygen Water quality and dissolved oxygen (DO) content in parts per million (ppm) (DO) content in parts per million (ppm) at 20at 20°C.°C. Only a few fish species can survive in Only a few fish species can survive in

water less than 4ppm at water less than 4ppm at 2020°C.°C. Figure 21-3Figure 21-3

Chemicals such as nitrogen and phosphorus Chemicals such as nitrogen and phosphorus that stimulate the growth of plants and algae. that stimulate the growth of plants and algae. Read “The Dead Zone” Raven, page 517.Read “The Dead Zone” Raven, page 517.

Inorganic Plant and Algal NutrientsInorganic Plant and Algal Nutrients

CausesCauses Nitrates and phosphates come from Nitrates and phosphates come from

sources such as human and animal sources such as human and animal wastes, plant residues, wastes, plant residues, atmospheric deposition and atmospheric deposition and residential land.residential land.

Environmental EffectsEnvironmental Effects Inorganic plant and algal nutrients Inorganic plant and algal nutrients

encourage excessive growth of algal encourage excessive growth of algal and aquatic plants. This causes and aquatic plants. This causes problems, including enrichment and bad problems, including enrichment and bad odor.odor.

CausesCauses Chemicals that contain carbon atoms. Chemicals that contain carbon atoms.

Most of the thousands of organic Most of the thousands of organic compounds found in water are synthetic compounds found in water are synthetic chemicals that are produced by human chemicals that are produced by human activities; these included pesticides, activities; these included pesticides, solvents, industrial chemicals and solvents, industrial chemicals and plastics, and seepage from landfills.plastics, and seepage from landfills.

Organic CompoundsOrganic Compounds


Hundreds of synthetic organic Hundreds of synthetic organic compounds are toxic and some of compounds are toxic and some of these have been shown to cause these have been shown to cause cancer or birth defects.cancer or birth defects.

Pollutes streams and Pollutes streams and groundwater.groundwater.


Inorganic Inorganic CompoundsCompounds

CausesCauses Chemicals are contaminants that Chemicals are contaminants that

contain elements other than carbon. contain elements other than carbon. Examples include acids, salts, and Examples include acids, salts, and heavy metals. Many inorganic heavy metals. Many inorganic chemicals find their way into both chemicals find their way into both surface water and groundwater from surface water and groundwater from sources such as industries, mines, sources such as industries, mines, irrigation runoff, oil drilling and urban irrigation runoff, oil drilling and urban runoff from storm sewers.runoff from storm sewers.

Environmental EffectsEnvironmental EffectsSome of these Some of these

inorganic inorganic pollutants are pollutants are toxic to toxic to aquatic aquatic organisms.organisms.

Health EffectsHealth Effects Lead and mercury are poisonous. Mercury Lead and mercury are poisonous. Mercury

exposure to developing fetuses in pregnant exposure to developing fetuses in pregnant women has been linked to a variety of women has been linked to a variety of conditions such as mental retardations, conditions such as mental retardations, cerebral palsy, and developing delays, cerebral palsy, and developing delays, causes kidney disorders and several causes kidney disorders and several damage the nervous and cardiovascular damage the nervous and cardiovascular systems.systems.Low levels of mercury in the brain cause Low levels of mercury in the brain cause

neurological problems such as headache, neurological problems such as headache, depression, and quarrelsome behavior.depression, and quarrelsome behavior.

Radioactive SubstancesRadioactive Substances

Contains atoms of unstable isotopes Contains atoms of unstable isotopes that spontaneously emit radiationthat spontaneously emit radiation

CausesCauses Radioactive substances get into water Radioactive substances get into water

from several sources like the mining from several sources like the mining and processing of radioactive minerals and processing of radioactive minerals such as uranium and thorium. such as uranium and thorium.

The nuclear weapons industry use the The nuclear weapons industry use the largest amounts.largest amounts.

Medical and scientific research Medical and scientific research facilities also use them.facilities also use them.

Health EffectsHealth Effects Mutations, birth defects, mental Mutations, birth defects, mental

retardation, genetic disease, leukemia, retardation, genetic disease, leukemia, cancer (breast, bone, thyroid, skin, cancer (breast, bone, thyroid, skin, lung), burns, cataracts, male sterility.lung), burns, cataracts, male sterility.

Pollutes air, water and soil.Pollutes air, water and soil.


CausesCauses

When heated water produced When heated water produced during certain industrial during certain industrial processes is released into processes is released into waterways.waterways.

Thermal PollutionThermal Pollution


Decomposition of wastes occurs Decomposition of wastes occurs faster, depleting the water of faster, depleting the water of oxygen; this affects aquatic life.oxygen; this affects aquatic life.

Typically affects animals, not Typically affects animals, not humans.humans.


WATER POLLUTION: SOURCES, WATER POLLUTION: SOURCES, TYPES, AND EFFECTSTYPES, AND EFFECTS

Water pollutionWater pollution is any chemical, biological, is any chemical, biological, or physical change in water quality that has a or physical change in water quality that has a harmful effect on living organisms or makes harmful effect on living organisms or makes water unsuitable for desired uses.water unsuitable for desired uses. Point sourcePoint source : specific location (drain pipes, : specific location (drain pipes,

ditches, sewer lines).ditches, sewer lines). Nonpoint sourceNonpoint source : cannot be traced to a single : cannot be traced to a single

site of discharge (atmospheric deposition, site of discharge (atmospheric deposition, agricultural / industrial / residential runoff) agricultural / industrial / residential runoff)

Point Source PollutionPoint Source Pollution

Water pollution that can be traced Water pollution that can be traced to a specific spot (such as a factory to a specific spot (such as a factory or sewage treatment plant) or sewage treatment plant) because it is discharged into the because it is discharged into the environment through pipes, sewers environment through pipes, sewers or ditches.or ditches.

Non-Point Source PollutionNon-Point Source Pollution

Pollutants that enter bodies of Pollutants that enter bodies of water over large areas rather than water over large areas rather than being concentrated at a single point being concentrated at a single point of entry. Ex. Agricultural fertilizer of entry. Ex. Agricultural fertilizer runoff and sediments from runoff and sediments from construction.construction.

Table 21-2, p. 495

AgricultureAgricultureFertilizers, animal wastes, etc.Fertilizers, animal wastes, etc.

Sources of PollutionSources of Pollution

Sewage, fertilizers, dumping Sewage, fertilizers, dumping into drainage ditches, etc.into drainage ditches, etc.

Municipal WasteMunicipal Waste

Industrial WasteIndustrial WasteChemicals left over from Chemicals left over from manufacturing, waste products, etc.manufacturing, waste products, etc.

Cultural EutrophicationCultural Eutrophication EutrophicationEutrophication : the natural nutrient : the natural nutrient

enrichment of a shallow lake, estuary or slow enrichment of a shallow lake, estuary or slow moving stream, mostly from runoff of plant moving stream, mostly from runoff of plant nutrients from the surrounding land.nutrients from the surrounding land.

Cultural eutrophicationCultural eutrophication : human activities : human activities accelerate the input of plant nutrients (mostly accelerate the input of plant nutrients (mostly nitrate- and phosphate-containing effluents) nitrate- and phosphate-containing effluents) to a lake.to a lake. 85% of large lakes near major population centers 85% of large lakes near major population centers

in the U.S. have some degree of cultural in the U.S. have some degree of cultural eutrophication.eutrophication.

DefinitionDefinition The enrichment of a lake or pond by The enrichment of a lake or pond by

inorganic plant and algal nutrients inorganic plant and algal nutrients such as phosphorus.such as phosphorus.

EutrophicationEutrophication

Because this gets into our water supply Because this gets into our water supply from runoff, etc., and is something that is from runoff, etc., and is something that is not normally in the water, it is considered not normally in the water, it is considered pollution.pollution.

Relation to PollutionRelation to Pollution

Cause/EffectCause/Effect Fertilizers, erosion, sewage, etc. get Fertilizers, erosion, sewage, etc. get

into water and the effect is high into water and the effect is high photosynthetic productivity. photosynthetic productivity.

Thus, the water is cloudy and usually Thus, the water is cloudy and usually resembles pea soup because of the resembles pea soup because of the algae and cyanobacteria that are algae and cyanobacteria that are supported by the nutrients.supported by the nutrients.

POLLUTION OF FRESHWATER POLLUTION OF FRESHWATER STREAMSSTREAMS

Flowing streams can recover from a Flowing streams can recover from a moderate level of degradable water moderate level of degradable water pollutants if they are not overloaded pollutants if they are not overloaded and their flows are not reduced.and their flows are not reduced. In a flowing stream, the breakdown of In a flowing stream, the breakdown of

degradable wastes by bacteria depletes degradable wastes by bacteria depletes DO and creates and DO and creates and oxygen sag curveoxygen sag curve ..

This reduces or eliminates populations of This reduces or eliminates populations of organisms with high oxygen requirements.organisms with high oxygen requirements.

Water Pollution Problems in Water Pollution Problems in StreamsStreams

Dilution and decay of degradable, oxygen-Dilution and decay of degradable, oxygen-demanding wastes and heat in a stream.demanding wastes and heat in a stream.


Fig. 21-4, p. 497

8 ppm

Biologicaloxygendemand

Dissolvedoxygen(ppm)

Types oforganisms

8 ppm

Recovery

ZoneSeptic ZoneDecomposition

ZoneClean Zone

Fish absent,fungi, sludgeworms,bacteria

(anaerobic)

Trash fish(carp, gar,leeches)

Clean Normal clean

water organisms

(Trout, perch, bass,

mayfly, stonefly)

Normal clean water

organisms

(Trout, perch, bass,

mayfly, stonefly)

Clean Zone

Trash fish(carp, gar,leeches)

POLLUTION OF FRESHWATER POLLUTION OF FRESHWATER STREAMSSTREAMS

Most developed countries have sharply Most developed countries have sharply reduced point-source pollution but toxic reduced point-source pollution but toxic chemicals and pollution from nonpoint chemicals and pollution from nonpoint sources are still a problem.sources are still a problem.

Stream pollution from discharges of Stream pollution from discharges of untreated sewage and industrial wastes untreated sewage and industrial wastes is a major problem in developing is a major problem in developing countries.countries.

Global Outlook: Stream Pollution Global Outlook: Stream Pollution in Developing Countriesin Developing Countries

Water in many of Water in many of central China's central China's rivers are greenish rivers are greenish black from black from uncontrolled uncontrolled pollution by pollution by thousands of thousands of factories.factories.


Case Study: India’s Ganges River: Case Study: India’s Ganges River: Religion, Poverty, and HealthReligion, Poverty, and Health

Religious beliefs, cultural traditions, poverty, Religious beliefs, cultural traditions, poverty, and a large population interact to cause and a large population interact to cause severe pollution of the Ganges River in India.severe pollution of the Ganges River in India. Very little of the sewage is treated.Very little of the sewage is treated. Hindu believe in cremating the dead to free the Hindu believe in cremating the dead to free the

soul and throwing the ashes in the holy Ganges.soul and throwing the ashes in the holy Ganges. Some are too poor to afford the wood to fully cremate.Some are too poor to afford the wood to fully cremate. Decomposing bodies promote disease and depletes Decomposing bodies promote disease and depletes

DO.DO.

Case Study: India’s Ganges River: Case Study: India’s Ganges River: Religion, Poverty, and HealthReligion, Poverty, and Health

Daily, more than 1 Daily, more than 1 million Hindus in million Hindus in India bathe, drink India bathe, drink from, or carry out from, or carry out religious religious ceremonies in the ceremonies in the highly polluted highly polluted Ganges River.Ganges River.


POLLUTION OF POLLUTION OF FRESHWATER LAKESFRESHWATER LAKES Dilution of pollutants in lakes is less effective Dilution of pollutants in lakes is less effective

than in most streams because most lake than in most streams because most lake water is not mixed well and has little flow.water is not mixed well and has little flow. Lakes and reservoirs are often stratified and Lakes and reservoirs are often stratified and

undergo little mixing.undergo little mixing. Low flow makes them susceptible to runoff.Low flow makes them susceptible to runoff.

Various human activities can overload lakes Various human activities can overload lakes with plant nutrients, which decrease DO and with plant nutrients, which decrease DO and kill some aquatic species.kill some aquatic species.

Importance of the Importance of the Ocean Ocean EnvironmentEnvironment

Marine EcologyMarine Ecology

AreaArea

Saltwater covers about 71% of Saltwater covers about 71% of the earth’s surfacethe earth’s surface

Life:There are 250,000 known species of marine plants and animals, many are food for other organisms, like us.

TemperatureTemperature Solar heat is distributed by ocean currents & Solar heat is distributed by ocean currents &

as ocean water evaporates. as ocean water evaporates. The oceans are major players in the earth’s The oceans are major players in the earth’s

climate & are a gigantic reservoir for carbon climate & are a gigantic reservoir for carbon dioxide; therefore they help regulate the temp. dioxide; therefore they help regulate the temp. of the troposphereof the troposphere..

Zones of the Marine Zones of the Marine EnvironmentEnvironment

Two major zones that break Two major zones that break up into smaller zones – up into smaller zones –

coastal and the open seacoastal and the open sea

Intertidal or Beach Intertidal or Beach ZoneZone

Broken up into five areasBroken up into five areas

Lower ShorefaceLower ShorefaceThe deepest part of the beach; The deepest part of the beach;

farther into the water, before the farther into the water, before the breaker bar that forms wavesbreaker bar that forms waves

Upper ShorefaceUpper ShorefaceShallow zone where the waves Shallow zone where the waves

begin to formbegin to form

ForebeachForebeachContains the swash zone – Contains the swash zone –

place where the waves crash.place where the waves crash.

BackbeachBackbeachOnly under water during high tideOnly under water during high tide

Fore-Island DunesFore-Island DunesSand dunes; doesn't flood often, Sand dunes; doesn't flood often,

except during hurricanes, etc. except during hurricanes, etc. Constantly changing due to the windConstantly changing due to the wind

EstuaryEstuary

Where fresh water and salt Where fresh water and salt water meetwater meet

An estuary is a coastal body of water, partly surrounded by land, with access to the open ocean and a large supply of fresh water from a river

CharacteristicsCharacteristics

SalinitySalinity

Salinity fluctuates with tidal cycles, Salinity fluctuates with tidal cycles, the time of year, & precipitation. the time of year, & precipitation. The organisms that live here must The organisms that live here must be able to tolerate these conditionsbe able to tolerate these conditions

Fertility of EstuariesFertility of Estuaries

Estuaries are the most fertile Estuaries are the most fertile ecosystems in the worldecosystems in the world

Greater productivity than either the Greater productivity than either the adjacent ocean or the fresh water adjacent ocean or the fresh water upriverupriver

Reasons for High FertilityReasons for High Fertility Nutrients are transported from the land into Nutrients are transported from the land into

rivers that flow into the estuaryrivers that flow into the estuary Tidal action circulates nutrients and helps Tidal action circulates nutrients and helps

remove wastesremove wastes A high level of light due to shallow waterA high level of light due to shallow water Many plants provide an extensive Many plants provide an extensive

photosynthetic carpetphotosynthetic carpet

DifficultiesDifficulties Sandy beach – Life must deal with a shifting Sandy beach – Life must deal with a shifting

environment that threatens to engulf them & no environment that threatens to engulf them & no protection against wave action. Most animals protection against wave action. Most animals bury into the sand. They move with the tides, bury into the sand. They move with the tides, so they’re always underwater & don’t dry out. so they’re always underwater & don’t dry out.

Difficulties (Continued)Difficulties (Continued) Rocky shore – high Rocky shore – high wave action at high tide; drying wave action at high tide; drying

out & temperature changes during low. Animals out & temperature changes during low. Animals have a way of sealing in moisture like a shell & have a way of sealing in moisture like a shell & find a way to cling to the rocks so they don’t get find a way to cling to the rocks so they don’t get washed away with waves.washed away with waves.

PelagicPelagic

The open ocean environment; The open ocean environment; divided into neritic (open ocean divided into neritic (open ocean from the shoreline to a depth of from the shoreline to a depth of 200m) and oceanic provinces 200m) and oceanic provinces (depths > 200m).(depths > 200m).

The Open Ocean

Euphotic ZoneEuphotic ZoneLots of light. Lots of light.

From 0 - 200 From 0 - 200 meters. meters. PhotosynthesiPhotosynthesis takes place s takes place here.here.

Bathyal ZoneBathyal Zone

The dimly lit The dimly lit part of ocean. part of ocean. From 200 - From 200 - 1500 meters.1500 meters.

Benthic Characteristics (ocean floor)Benthic Characteristics (ocean floor) The ocean floor consists of sediments The ocean floor consists of sediments

(mostly sand and mud) (mostly sand and mud) Many marine animals, like worms and Many marine animals, like worms and

clams, burrow clams, burrow Bacteria are common & can go down 500 Bacteria are common & can go down 500

meters below ocean floor. The Benthic meters below ocean floor. The Benthic environment extends from the shore to the environment extends from the shore to the deep.deep.

Sea Grass BedsSea Grass BedsFlowering plants that have adapted to Flowering plants that have adapted to

complete submersion in salty water.complete submersion in salty water.

Location of sea grassLocation of sea grass

Found in shallow water to depths of Found in shallow water to depths of 10 meters where they can 10 meters where they can photosynthesize. Sea grasses are photosynthesize. Sea grasses are found in quiet, temperate, tropical, found in quiet, temperate, tropical, and subtropical waters; not in polar and subtropical waters; not in polar waters.waters.

Eel, turtle, and manatee grass.Eel, turtle, and manatee grass.ExamplesExamples

Ecological ImportanceEcological Importance

Reduce surface erosion, provide Reduce surface erosion, provide food, & provide habitats for many food, & provide habitats for many marine organisms.marine organisms.

Animals that eat sea grass are Animals that eat sea grass are manatees, green turtles, parrotfish, manatees, green turtles, parrotfish, sturgeon fish, and sea urchins.sturgeon fish, and sea urchins.

Abyssal ZoneAbyssal Zone Completely dark. Completely dark.

Extends to a depth Extends to a depth of 4000 to 6000 of 4000 to 6000 meters (2.5 to 3.7 meters (2.5 to 3.7 miles). Water here miles). Water here is very cold & has is very cold & has little dissolved little dissolved oxygen.oxygen.

KelpKelp

The largest of the brown algae, many reach The largest of the brown algae, many reach lengths of 60 meters (200 feet). Common in lengths of 60 meters (200 feet). Common in cooler water & are found along rocky coasts. cooler water & are found along rocky coasts. Provide habitat for many animals like Provide habitat for many animals like tubeworms, sponges, clams, fish, & tubeworms, sponges, clams, fish, & mammals. Some animals eat the kelp.mammals. Some animals eat the kelp.

CharacteristicsCharacteristics Built from layers of calcium carbonate, Built from layers of calcium carbonate,

coral reefs are found in warm, shallow sea coral reefs are found in warm, shallow sea water. The living portions must grow in water. The living portions must grow in shallow waters where light hits. They are shallow waters where light hits. They are the most diverse of all marine ecosystems.the most diverse of all marine ecosystems.

Coral ReefsCoral Reefs

ExamplesExamples Many coral reefs are made of red coralline Many coral reefs are made of red coralline

algae that photosynthesize. algae that photosynthesize. Others have zooxanthellae (symbiotic algae) Others have zooxanthellae (symbiotic algae)

that live and photosynthesize in their tissues. that live and photosynthesize in their tissues. Not all corals have zooxanthellae, but only Not all corals have zooxanthellae, but only

those with it build reefs. those with it build reefs. Coral animals also capture food at night with Coral animals also capture food at night with

stinging tentacles that paralyze zooplankton stinging tentacles that paralyze zooplankton and small animals that drift nearby.and small animals that drift nearby.

Coral Reef WatersCoral Reef Waters

The waters where coral reefs are The waters where coral reefs are found are often poor in nutrients. found are often poor in nutrients. Yet, other factors are favorable Yet, other factors are favorable such as temperature, sunlight year such as temperature, sunlight year round, and zooxanthellae.round, and zooxanthellae.

GrowthGrowth

Coral reefs grow slowly; as one Coral reefs grow slowly; as one dies, another organism grows dies, another organism grows on it.on it.

Fringing ReefFringing Reef

The most common type of coral The most common type of coral reef. It is directly attached to reef. It is directly attached to the shore of a volcanic island or the shore of a volcanic island or continent.continent.

Types of Coral Reefs

Fringing Reef Bora Bora NASA JPL Satellite: Space Shuttle Sensor: SIR-C/X-SAR

AtollAtoll

A circular reef that surrounds a A circular reef that surrounds a central lagoon of quiet water. central lagoon of quiet water.

An atoll forms on top of the cone of a An atoll forms on top of the cone of a submerged volcanic island. submerged volcanic island.

More than 300 atolls are found in the More than 300 atolls are found in the Pacific and Indian Oceans.Pacific and Indian Oceans.

View of Midway Atoll from Space Shuttle

Atolls in The Maldives Landsat 7

Barrier ReefBarrier Reef

A lagoon of open water separates A lagoon of open water separates the land from the barrier reef. the land from the barrier reef.

The largest barrier reef is the Great The largest barrier reef is the Great Barrier Reef off the coast of Barrier Reef off the coast of Australia. Australia.

The second largest is off the coast The second largest is off the coast of Belize.of Belize.

Provides a HabitatProvides a HabitatProvides a habitat for a wide Provides a habitat for a wide

variety of marine organisms.variety of marine organisms.

Ecological Importance Ecological Importance of Coral Reefsof Coral Reefs

Coastline ProtectionCoastline Protection

Protects coasts from shoreline Protects coasts from shoreline erosion.erosion.

Benefits for HumansBenefits for Humans

Provides humans with seafood, Provides humans with seafood, pharmaceuticals, and pharmaceuticals, and recreational/tourism dollarsrecreational/tourism dollars

Coral Reef RisksCoral Reef Risks Of the 109 countries with large reefs, Of the 109 countries with large reefs,

90 are damaging them, and 27% of 90 are damaging them, and 27% of the coral reefs are at high risk, the coral reefs are at high risk, especially off the coast of especially off the coast of Southeastern Asia.Southeastern Asia.

In the western Atlantic, 30-50% of all In the western Atlantic, 30-50% of all coral species are either rare or coral species are either rare or endangered.endangered.

Coral Reef Risks Con’tCoral Reef Risks Con’t Silt washing from downstream has Silt washing from downstream has

smothered the reefssmothered the reefs High salinity from fresh water diversion, High salinity from fresh water diversion,

over-fishing, boat groundings, fishing over-fishing, boat groundings, fishing with dynamite or cyanide, hurricane with dynamite or cyanide, hurricane damage, disease, coral bleaching, land damage, disease, coral bleaching, land reclamation, tourism, and the mining of reclamation, tourism, and the mining of coral for building materials.coral for building materials.

©1997-2001 Jeffrey N. Jeffords

This bottle still shows a slightly burned fuse from its use to blow up the coral.

Protection ofProtection of

300 coral reefs in 65 countries are 300 coral reefs in 65 countries are protected as reserves or parks, and protected as reserves or parks, and another 600 have been another 600 have been recommended for protection.recommended for protection.

The good news is coral reefs can The good news is coral reefs can often recover from damage.often recover from damage.

Differences of OpinionDifferences of Opinion Oceans dilute, disperse, and degrade large Oceans dilute, disperse, and degrade large

amounts of raw sewage, sewage sludge, oil, amounts of raw sewage, sewage sludge, oil, and some types of industrial waste, especially and some types of industrial waste, especially in deep-water areas. in deep-water areas.

Marine life has proved to be more resilient than Marine life has proved to be more resilient than some scientists expected, some suggest it is some scientists expected, some suggest it is safer to dump sludge & other hazardous safer to dump sludge & other hazardous wastes into the deep ocean than to bury them wastes into the deep ocean than to bury them on land or burn them.on land or burn them.

Differences of OpinionDifferences of Opinion Other scientists disagree, pointing out Other scientists disagree, pointing out

that we know less about the deep that we know less about the deep ocean than we do about space. ocean than we do about space. They say that dumping waste in the They say that dumping waste in the ocean would delay urgently needed ocean would delay urgently needed pollution prevention and promote pollution prevention and promote further degradation of this vital part further degradation of this vital part of the earth’s life-support system.of the earth’s life-support system.

Oil SpillsOil Spills When a tanker accident happens, it gets lots When a tanker accident happens, it gets lots

of publicity. of publicity. But, more oil is released by normal operation But, more oil is released by normal operation

of offshore wells, washing tankers & from of offshore wells, washing tankers & from pipeline or storage tank leaks. pipeline or storage tank leaks.

One estimate says that oil companies spill, One estimate says that oil companies spill, leak, or waste per year an amount of oil leak, or waste per year an amount of oil equal to that shipped by 1000 huge Exxon equal to that shipped by 1000 huge Exxon Valdez tankers.Valdez tankers.

Floating OilFloating Oil

Oil coats the feathers of birds (especially Oil coats the feathers of birds (especially diving birds) and the fur of marine diving birds) and the fur of marine animals, destroying the animals’ natural animals, destroying the animals’ natural insulation and buoyancyinsulation and buoyancy

Many drown or die of exposure from loss Many drown or die of exposure from loss of body heat.of body heat.

Other InformationOther Information Oil is broken down by bacteria over time; Oil is broken down by bacteria over time;

slower in cold waters.slower in cold waters. Heavy oil components can smother bottom-Heavy oil components can smother bottom-

dwelling organisms such as crabs, oysters, dwelling organisms such as crabs, oysters, mussels, and clams, or make them unfit to eat.mussels, and clams, or make them unfit to eat.

Oil spills have killed coral reefs. A recent Oil spills have killed coral reefs. A recent study showed that diesel oil becomes more study showed that diesel oil becomes more toxic to marine life with the passage of time.toxic to marine life with the passage of time.

Mechanical MethodsMechanical Methods Floating booms contain the oil spill or keep it Floating booms contain the oil spill or keep it

from reaching sensitive areasfrom reaching sensitive areas Skimmer boats are used to vacuum up some of Skimmer boats are used to vacuum up some of

the oil into collection bargesthe oil into collection barges Absorbent pads or large feather-filled pillows Absorbent pads or large feather-filled pillows

are used to soak up oil on beaches or in waters are used to soak up oil on beaches or in waters that are too shallow for skimmer boatsthat are too shallow for skimmer boats

Chemical MethodsChemical Methods Coagulating agents cause floating oil to clump Coagulating agents cause floating oil to clump

together for easier pickup or sink to the bottom, together for easier pickup or sink to the bottom, where it usually does less harm.where it usually does less harm.

Dispersing agents break up oil slicks. Dispersing agents break up oil slicks. However, these can also damage some types However, these can also damage some types of organisms.of organisms.

Fire can also burn off floating oil, but crude oil Fire can also burn off floating oil, but crude oil is hard to ignite.is hard to ignite.

Reducing Water Pollution through Reducing Water Pollution through Sewage TreatmentSewage Treatment

Septic tanks and various levels of Septic tanks and various levels of sewage treatment can reduce point-sewage treatment can reduce point-source water pollution.source water pollution.



Primary and Secondary sewage treatment.Primary and Secondary sewage treatment.Figure 21-16Figure 21-16


Advanced or tertiary sewage treatment:Advanced or tertiary sewage treatment: Uses series of chemical and physical Uses series of chemical and physical

processes to remove specific pollutants left processes to remove specific pollutants left (especially nitrates and phosphates).(especially nitrates and phosphates).

Water is chlorinated to remove Water is chlorinated to remove coloration and to kill disease-carrying coloration and to kill disease-carrying bacteria and some viruses (disinfect). bacteria and some viruses (disinfect).


Raw sewage reaching a municipal sewage Raw sewage reaching a municipal sewage treatment plant typically undergoes:treatment plant typically undergoes: Primary sewage treatmentPrimary sewage treatment : a : a physicalphysical

process that uses screens and a grit tank to process that uses screens and a grit tank to remove large floating objects and allows settling.remove large floating objects and allows settling.

Secondary sewage treatmentSecondary sewage treatment : a : a biologicalbiological process in which aerobic bacteria remove as process in which aerobic bacteria remove as much as 90% of dissolved and biodegradable, much as 90% of dissolved and biodegradable, oxygen demanding organic wastes.oxygen demanding organic wastes.

Water TreatmentWater Treatment

PrimaryPrimary Removes suspended and floating Removes suspended and floating

particles, such as sand and silt, by particles, such as sand and silt, by mechanical processes such as mechanical processes such as screening and gravitational settling. screening and gravitational settling. The solid material that is settled out is The solid material that is settled out is called primary sludge.called primary sludge.

Bar screens, grit chambers, primary clarifiers, digesters and pre-aeration

SecondarySecondary Uses microorganisms to decompose Uses microorganisms to decompose

the suspended organic material in the suspended organic material in wastewater. Ex. trickling filters – where wastewater. Ex. trickling filters – where wastewater trickles through aerated wastewater trickles through aerated rock beds that contain bacteria and rock beds that contain bacteria and other microorganisms, which degrade other microorganisms, which degrade the organic material in the water. the organic material in the water.

Secondary (Cont.)Secondary (Cont.) Or activated sludge process – wastewater Or activated sludge process – wastewater

is aerated and circulated through bacteria-is aerated and circulated through bacteria-rich particles; the bacteria degrade rich particles; the bacteria degrade suspended organic material. After several suspended organic material. After several hours, the particles and microorganisms are hours, the particles and microorganisms are allowed to settle out, forming secondary allowed to settle out, forming secondary sludge.sludge.

Use aeration basins, settling tanks and Use aeration basins, settling tanks and sand filterssand filters

TertiaryTertiary This includes a variety of biological, chemical and This includes a variety of biological, chemical and

physical processes used to remove phosphorus physical processes used to remove phosphorus and nitrogen, the nutrients most commonly and nitrogen, the nutrients most commonly associated with enrichment. Tertiary treatment associated with enrichment. Tertiary treatment can also be used to purify wastewater so that it can also be used to purify wastewater so that it can be reused in communities where water is can be reused in communities where water is scarce. scarce.

Use chlorine as a disinfection and then chlorine is Use chlorine as a disinfection and then chlorine is removed by SO2 so it can be released into river.removed by SO2 so it can be released into river.


Sewage sludge can be used as a soil Sewage sludge can be used as a soil conditioner but this can cause health conditioner but this can cause health problems if it contains infectious problems if it contains infectious bacteria and toxic chemicals.bacteria and toxic chemicals.

Preventing toxic chemicals from Preventing toxic chemicals from reaching sewage treatment plants reaching sewage treatment plants would eliminate such chemicals from would eliminate such chemicals from the sludge and water discharged from the sludge and water discharged from such plants.such plants.


Natural and artificial wetlands and other Natural and artificial wetlands and other ecological systems can be used to treat ecological systems can be used to treat sewage.sewage. California created a 65 hectare wetland California created a 65 hectare wetland

near Humboldt Bay that acts as a natural near Humboldt Bay that acts as a natural wastewater treatment plant for the town of wastewater treatment plant for the town of 16,000 people.16,000 people.

The project cost less than half of the estimated The project cost less than half of the estimated price of a conventional treatment plant.price of a conventional treatment plant.

United StatesUnited States Groundwater contamination still occurs, Groundwater contamination still occurs,

especially due to non-point source especially due to non-point source pollution, but laws like the Safe Drinking pollution, but laws like the Safe Drinking Water Act, Clean Water Act, and Water Water Act, Clean Water Act, and Water Quality Act have helped in the U.S.Quality Act have helped in the U.S.

Water QualityWater Quality

Global ProblemsGlobal Problems According to the World Health According to the World Health

Organization, an estimated 1.4 billion Organization, an estimated 1.4 billion people still do not have access to people still do not have access to adequate sanitation systems. adequate sanitation systems. Worldwide, at least 250 million cases of Worldwide, at least 250 million cases of water-related illnesses occur each year, water-related illnesses occur each year, with 5 million or more of these resulting with 5 million or more of these resulting in death. Read Raven page 535-536.in death. Read Raven page 535-536.

Dissolved OxygenDissolved Oxygen The amount of oxygen gas dissolved in a The amount of oxygen gas dissolved in a

given volume of water at a particular given volume of water at a particular temperature and pressure.temperature and pressure.

Specific Water Quality MeasuresSpecific Water Quality Measures

Carbon DioxideCarbon Dioxide Enters aquatic systems from the Enters aquatic systems from the

atmosphere and from respiration by atmosphere and from respiration by animals.animals.

The concentration of CO2 varies at The concentration of CO2 varies at different depths because of different depths because of light/photosynthesis.light/photosynthesis.

NitrateNitrate Contaminates shallow groundwater Contaminates shallow groundwater

(100 feet or less) and usually comes (100 feet or less) and usually comes from fertilizers. It’s a concern in rural from fertilizers. It’s a concern in rural areas where 80-90% of the residents areas where 80-90% of the residents use shallow groundwater for drinking. use shallow groundwater for drinking. This harms humans because it reduces This harms humans because it reduces the blood’s ability to transport oxygen.the blood’s ability to transport oxygen.

SulfateSulfate

Problem because too much can Problem because too much can kill fish. Gets in water from kill fish. Gets in water from industrial processes and industrial processes and mining.mining.

IronIron

Causes problems because it Causes problems because it separates out of the water and separates out of the water and forms particulates (sediment), it forms particulates (sediment), it tastes bad if it gets in our water, tastes bad if it gets in our water, and can coat fish’s gills. and can coat fish’s gills. Groundwater problems in wells, Groundwater problems in wells, from natural minerals in rocks.from natural minerals in rocks.

PhosphatePhosphate

Plant nutrients that cause algae Plant nutrients that cause algae blooms. It comes from detergents, blooms. It comes from detergents, human wastes and fertilizers.human wastes and fertilizers.

ColiformColiform

General group of bacteria from General group of bacteria from animal wastes. It uses up animal wastes. It uses up available oxygen. Also causes available oxygen. Also causes e-coli disease.e-coli disease.

GiardiaGiardia

Organism (protozoa) that can Organism (protozoa) that can cause diarrhea if you drink cause diarrhea if you drink unchlorinated water. It is a natural unchlorinated water. It is a natural organism that lives in the guts of organism that lives in the guts of animals.animals.

ChlorideChloride

Part of salts, but too many can Part of salts, but too many can cause too much salt in the water. cause too much salt in the water. Too much is bad; a little is okay. It Too much is bad; a little is okay. It is naturally found in water, but can is naturally found in water, but can come from pollution.come from pollution.

pHpH

Too high/too low can be bad; Too high/too low can be bad; fish like 6.5-9.5; acid mine fish like 6.5-9.5; acid mine drainage can kill fish.drainage can kill fish.

HardnessHardness

Calcium and magnesium dissolved Calcium and magnesium dissolved in the water. A little is good (50-in the water. A little is good (50-400 ppm for fish is good), but very 400 ppm for fish is good), but very low or high is a problem. Low is low or high is a problem. Low is more of a problem. Affects fish more of a problem. Affects fish eggs, poor bone development.eggs, poor bone development.

DefinitionDefinitionCalcium and magnesium in the Calcium and magnesium in the

water. Can cause problems with water. Can cause problems with cleaning clothes. Soap doesn’t cleaning clothes. Soap doesn’t bubble as much.bubble as much.

Hard WaterHard Water

TurbidityTurbidity

Cloudiness/muddiness; blocks Cloudiness/muddiness; blocks the light; coats fish gills.the light; coats fish gills.

Ion ExchangeIon ExchangeSubstitute sodium for calcium and Substitute sodium for calcium and

magnesium. Water softeners magnesium. Water softeners usually do this.usually do this.

Methods of TreatingMethods of Treating

Reverse OsmosisReverse Osmosis

Membrane system that allows Membrane system that allows water to go through but calcium water to go through but calcium and magnesium cannot. and magnesium cannot.

Major Users – United States & globalMajor Users – United States & global

Agricultural users are the biggest Agricultural users are the biggest by volume, then industrial and by volume, then industrial and municipal.municipal.

Water UsageWater Usage

POLLUTION OF POLLUTION OF GROUNDWATERGROUNDWATER

Leaks from a number of sources have Leaks from a number of sources have contaminated groundwater in parts of contaminated groundwater in parts of the world.the world. According the the EPA, one or more According the the EPA, one or more

organic chemicals contaminate about 45% organic chemicals contaminate about 45% of of municipalmunicipal groundwater supplies. groundwater supplies.

By 2003, the EPA had completed the By 2003, the EPA had completed the cleanup of 297,000 of 436,000 cleanup of 297,000 of 436,000 underground tanks leaking gasoline, diesel underground tanks leaking gasoline, diesel fuel, home heating oil, or toxic solvents.fuel, home heating oil, or toxic solvents.

Case Study: Arsenic in Case Study: Arsenic in Groundwater - a Natural ThreatGroundwater - a Natural Threat

Toxic Arsenic (Toxic Arsenic (AsAs) can naturally occur at high ) can naturally occur at high levels in soil and rocks.levels in soil and rocks.

Drilling into aquifers can release Drilling into aquifers can release AsAs into into drinking water supplies.drinking water supplies.

According to WHO, more than 112 million According to WHO, more than 112 million people are drinking water with people are drinking water with AsAs levels 5- levels 5-100 times the 10 ppb standard.100 times the 10 ppb standard. Mostly in Bangladesh, China, and West Bengal, Mostly in Bangladesh, China, and West Bengal,

India.India.

Safe Drinking Water ActSafe Drinking Water Act It required the EPA to determine the maximum It required the EPA to determine the maximum

contaminant level, the max permissible amount contaminant level, the max permissible amount of any pollutant that might adversely affect of any pollutant that might adversely affect human health.human health.

Water LegislationWater Legislation

PREVENTING AND REDUCING PREVENTING AND REDUCING SURFACE WATER POLLUTIONSURFACE WATER POLLUTION

Most developed countries use laws to set Most developed countries use laws to set water pollution standards, but such laws water pollution standards, but such laws rarely exist in developing countries.rarely exist in developing countries. The U.S. Clean Water Act sets standards for The U.S. Clean Water Act sets standards for

allowed levels of key water pollutants and allowed levels of key water pollutants and requires polluters to get permits.requires polluters to get permits.

EPA is experimenting with a EPA is experimenting with a discharge discharge trading policytrading policy similar to that for air pollution similar to that for air pollution control.control.

Clean Water ActClean Water Act

Has two basic goals:Has two basic goals: To eliminate the discharge of pollutants in To eliminate the discharge of pollutants in

U.S. waterwaysU.S. waterways

To attain water quality levels that make these To attain water quality levels that make these waterways safe to fish and swim in.waterways safe to fish and swim in.

Water Quality ActWater Quality Act•controlling toxic pollutant discharges

•control non-point sources of pollution

•authorized $18 billion for wastewater treatment

•address problems such as coastal estuaries, the Great Lakes, and the Chesapeake Bay

Using Laws to Protect Drinking Using Laws to Protect Drinking WaterWater The U.N. estimates that 5.6 million Americans The U.N. estimates that 5.6 million Americans

drink water that does not meet EPA standards.drink water that does not meet EPA standards. 1 in 5 Americans drinks water from a treatment 1 in 5 Americans drinks water from a treatment

plant that violated one or more safety standard.plant that violated one or more safety standard. Industry pressures to weaken the Safe Drinking Industry pressures to weaken the Safe Drinking

Act:Act: Eliminate national tests and public notification of Eliminate national tests and public notification of

violations. violations. Allow rights to pollute if provider cannot afford to Allow rights to pollute if provider cannot afford to

comply.comply.

Is Bottled Water the Answer?Is Bottled Water the Answer? Some bottled water is not as pure as Some bottled water is not as pure as

tap water and costs much more.tap water and costs much more. 1.4 million metric tons of plastic bottles are 1.4 million metric tons of plastic bottles are

thrown away.thrown away. Fossil fuels are used to make plastic Fossil fuels are used to make plastic

bottles.bottles. The oil used to produce plastic bottles in the The oil used to produce plastic bottles in the

U.S. each year would fuel 100,000 cars.U.S. each year would fuel 100,000 cars.

Science

Water quality notes