Chemical oxygen generators are used to furnish oxygen to the

What is an Environmentally Sustainable Society?

One that meets the current and future basic resource needs of its people in

a just and equitable manner without compromising the ability of the future

generations to meet their basic resource needs

Environmental Scientists

John Muir (1892) - created Yosemite National Parks

Created Sierra club

Eugene and Howard (1953) - wrote the first ecology textbook

Rachel Carson (1962) - wrote Silent Spring

Effects of DDT

Lois Gibbs (1980) - formed the Citizens Clearinghouse for hazardous

 waste, petition to Jimmy Carter

The town was called Love Canal

Theodore Roosevelt (1900) - created the United States Forest Service

 for Wildlife

Established 5 national parks

Antiquities Act

James Lovelock (1960s) - created the Gaia Theory

Aldo Leopold (1933) - "Father of Wildlife Management"

Wrote "A Sand County Almanac"

Forester, wildlife biologist  

Paul and Anne Ehrlich (1986) - wrote "The Population Bomb"

George Perkins Marsh (1864) - wrote "Man and Nature"

Deforestation can lead to Desertification

Edward O. Wilson (1996) - studied ants and their evolution; developed

 the theory "taxon cycle"

James Hansen (1941) - professor in the Department of Earth

and Environment

 Science at Columbia

Raised alarm bells about global warming

Coal and petroleum

Amory Lovins (1994) - Chief Scientist/Founder of Rocky Mountain Institute;

Advocated for energy-efficiency; In Time's Top 100 Most Influential People

 in 2009  - Promotes path to "soft-energy"

Something that is not harmful to the energy - Wind and solar energy

What is happening to tropical rainforests and what harmful effects result

from this?

Although they cover only about 2% of the earth’s land surface, studies

 indicate that they contain up to half of the world’s known terrestrial plant

and animal species

Scientists give 3 reasons why we would care that the tropical rain forests

are disappearing

Clearing these forests will reduce the earth’s vital biodiversity by destroying

 or degrading the habitats of many of the unique plant and animal species

that live in them, which could lead to the early extinction of these species

 and other species that depend on them

The destruction of these forests is helping to accelerate atmospheric warming,

and thus projected climate change

Large-scale rain forest losses can change regional weather patterns in ways

that can prevent the return of diverse tropical rain forests in cleared or

severely degraded areas

What 're 4 main spherical systems tht comprise earth’s “life support system”?

Atmosphere – a thin spherical envelop of gases surrounding the surface

Troposphere – inner layer which extends about 17 km (11mi)

above sea level at the tropics about 7 km (4mi) above the earth’s

north and south poles

Stratosphere – reaching from 17 to 50 km (11-31 mi) above the earth’s surface

Hydrosphere – made up of all the water on or near the earth’s surface

Found as water vapor in the atmosphere, as liquid water on the

surface and underground, and as ice-polar ice, icebergs, glaciers, and

ice in frozen soil-layer called permafrost

Geosphere – consists of the earth’s intensely hot core, a thick mantle

composed mostly of rock, and a thin outer crust

Crust’s upper portion contains soil chemicals that organisms need in

order to live, grow, and reproduce (nutrients), as well as nonrenewable

fossil fuels- coal, oil, and natural gas- and minerals that we use

Biosphere – consists of the parts of the atmosphere, hydrosphere, and

geosphere where life is found

An important goal of environmental science is to understand the key

interactions that occur within this thin layer of air, water, soil, and organisms

and how we interact with the biosphere

Components of an Ecosystem

Organisms, populations, communities, ecosystems, and the biosphere

Food chains – a sequence of organisms, each of which serves as a

source of nutrients or energy for the next

Food webs – organisms in most ecosystems form a complex network of

interconnected food chains

Trophic levels – each of several hierarchical levels sin an ecosystem,

comprising organisms that share the same function in the food chain

and the same nutritional relationship to the primary sources of energy

Pyramid of energy flow – this energy loss for a simple food chain,

assuming a 90% energy loss with each transfer

Energy moving through biospheres

Gross primary productivity (GPP) – the rate at which an ecosystem’s

producers (usually plants) convert solar energy into chemical energy

stored in compounds found in their tissues

Net primary productivity (NPP) – the rate at which producers use

photosynthesis to produce and store chemical energy minus the rate

at which they use some of tis stored chemical energy through

aerobic respiration

Also, NPP measures how fast producers can make the chemical energy

that is stored in their tissues and that is potentially available to other

organisms (consumers) in an ecosystem

Cycles

Nutrient cycle (biogeochemical cycle) – the elements and

compounds that make up nutrients move continually

through air, water, soil, rock, and living organisms within

ecosystems, as well as in the biosphere in cycles

Hydrologic cycle (water cycle) – collects, purifies, and distributes

 the earth’s fixed supply of water

Carbon Cycle – various compounds of carbon circulate through

 the biosphere, the atmosphere, and parts of the hydrosphere.

Nitrogen Cycle – cyclic movement of nitrogen in different chemical

forms from the environment to organisms and then back to environment

Nitrogen cannot be absorbed and used directly as a nutrient plants

 or animals, but as a component of compounds such as ammonia

 (NH3) and ammonium ions (NH4+), it becomes a plant nutrient.

Phosphorus Cycle - compounds of phosphorus P circulate through

water, the earth crust, and living organisms in cycle dcs

As water runs over exposed rocks, it slowly erodes away inorganic

compounds that contain phosphate ions and carries these ions into

the soil where they can be absorbed by the roots of plants and by

other producers. Phosphate compounds are then transferred by

food webs from producers to consumers and eventually to detritus

feeders and decomposers.  

Sulfur Cycle – much of the earth’s sulfur is stored underground in

 rocks and minerals and in the form of sulfate salts buried deep

under ocean sediments

Sulfur also enters the atmosphere from several natural sources.

 Hydrogen sulfide (H2S) – a colorless, highly poisonous gas with

a rotten-egg smell – is released from active volcanoes and from

organic matter broken down by anaerobic decomposers in

flooded swamps, bogs, and tidal flats.

Chapter 11

Groundwater

Some precipitation infiltrates the ground and percolates downward

through spaces in soil, gravel, and rock until an impenetrable layer

of rock or clay stops it. The freshwater in these spaces underground

is groundwater which is a key component of the earth’s natural capital

Layers of Groundwater

Zone of saturation – below a certain depth these spaces are completely

filled with freshwater

Water table – the top of the groundwater zone

Point sources – discharge pollutants into bodies of surface water at

specific locations through drain pipes, ditches, or sewer lines

Examples – factories, sewage treatment plants (which remove some,

 but not all pollutants), underground mines, oil wells, and oil makers

They are fairly easy to identify, monitor, and regulate

Nonpoint sources – broad and diffuse areas where rainfall or snowmelt

washes pollutants off the land into bodies of surface water

Examples – runoff of eroded soil and chemicals such as fertilizers and

pesticides from cropland, feedlots, logged forests, urban streets,

parking lots, lawns, and golf courses

Streams can cleanse themselves

Flowing rivers and streams can recover rapidly from moderate levels

of degradable, oxygen-demanding wastes through a combination

of dilution and bacterial biodegradation of such wastes. But this

natural recovery process does not work when a stream becomes

overloaded with such pollutants or when drought, damming, or

water diversion reduces its flow.

In a flowing stream, the breakdown of biodegradable wastes by

bacteria depletes dissolved oxygen and creates an oxygen sg curve.

This reduces or eliminates populations of organisms with high oxygen

 requirements until the stream is cleansed of oxygen-demanding wastes.

How lakes and reservoirs are vulnerable to pollution

Lakes and reservoirs often contain stratified layers that undergo

 little vertical mixing

They have low flow rates or no flow at all. The flushing and changing

of water in lakes and large artificial reservoirs can take from 1 to

100 years, compared with several days to several weeks for streams.

As a result, lakes and reservoirs are more vulnerable than streams are

to contamination by runoff or discharges of plant nutrients, oil,

pesticides, and non-degradable toxic substances, such as lead, mercury,

and arsenic. Many toxic chemicals and acids also enter lakes and

reservoirs from the atmosphere.

Oligotrophic and Eutrophic bodies of water

Oligotrophic Lake – lake with a low supply of plant nutrients

Eutrophic Lake – Lake with a large or excessive supply of plant

nutrients, mostly nitrates and phosphates

Ocean becoming to pollution

Oceans help to provide and recycle the planet’s freshwater

through the water cycle

They also strongly affect weather and climate, help to

regulate the earth’s temperature, and absorb some of the

massive amounts of carbon dioxide that we emit into the atmosphere

80-90% of the municipal sewage from coastal areas of less-developed

countries is dumped into oceans without treatment

this often overwhelms the ability of the coastal waters to degrade the waters

by adding excessive amounts of nitrates and phosphates to the

ocean instead of recycling these vital plant nutrients to the soil,

this activity alters the nitrogen and phosphorus cycles and upsets marine ecosystem.

Reducing runoff from the land make a big difference

in ocean pollution

Farmers can reduce soil erosion by keeping cropland covered w/

vegetation + using conservation tillage and other soil conversation methods

Also, they can reduce the amount of fertilizer that runs off into surface

waters by using slow-release fertilizer, using no fertilizer on steeply sloped

land, and planting buffer zones of vegetation between cultivated fields

and nearby surface waters

How algal blooms occur and why they are bad

They occur annually in several hundred oxygen-depleted zones

 around the world, mostly in temperate coastal waters and in large

 bodies of water with restricted outflows, such as the Baltic and Black Seas

They are bad because they can release waterborne and airborne toxins

that poison seafood, damage fisheries, kill some fish-eating birds, and

reduce tourism. Each year, harmful algal blooms lead to the poisoning of

about 60,000 Americans who eat shellfish contaminated by the algae

What is a dead zone and why has one formed in the Gulf of Mexico?

A dead zone is a hypoxic zone are areas in the ocean of such low

oxygen concentration that animal life suffocates and dies

Water draining into the Mississippi River and its tributaries from

 farms, cities, factories, and sewage treatments plants in this huge

 basin contains sediments and other pollutants that end up in

 the Gulf of Mexico – a major supplier of the country’s fish and shellfish.

Each spring and summer, this huge input of plant nutrients, mostly

nitrates from crop fertilizers, enters the northern Gulf of Mexico.

Great Pacific Garbage patch

ocean debris is continuously mixed by wind and wave action and

widely dispersed both over huge surface areas and throughout

the top portion of the water column

“Living Machine” and how can I be used to purify wastewater?

A “living machine” an ecological approach to treat sewage

The purification process begins when sewage flows into a

passive solar greenhouse or outdoor site containing rows o

f large open tanks populated by an increasingly complex

series of organisms. In the first set of tanks, algae and microorganisms

 decompose organic wastes, with sunlight speeding up the process.

Water hyacinths, cattails, bulrushes, and other aquatic plants growing

in the tanks take up the resulting nutrients.

After flowing through several of these natural purification tanks, the

water passes through an artificial marsh made of sand, gravel, and

bulrushes, which filters out algae and remaining organic waste.

Next, the water flows into aquarium tanks, where snails and zooplankton

 consume microorganisms and are in turn consumed by crayfish,

 tilapia, and other fish that can be eaten or sold as bait. After 10 days,

the clear water flows into a second artificial marsh for final filtering

and cleansing. The water can be made pure enough to drink by treating

it with ultraviolet light or by passing the water through an ozone generator.

Chapter 2

Hubbard Brook Forest Experiment and its findings

Their goal was to compare the loss of water and soil nutrients from an area

of uncut forest (the control site) with one that had been stripped of its trees

(the experimental site)

They built V-shaped concrete dams across the creeks at the bottoms of

several forested valleys

The dams were designed so that all surface water leaving each forested

valley had to flow across a dam, where scientists could measure its

 volume and dissolved nutrient content

First, the researchers measured the amounts of water and dissolved

soil nutrients flowing from an undisturbed forested area in one of the

valleys (the control site). These measurements showed that an

 undisturbed mature forest is very efficient at storing water and retaining

 chemical nutrients in its soil.

Next, they set up an experimental forest area in a nearby valley.

One winter, they cut down all the trees and shrubs in that valley,

left them where they fell, and sprayed the area with herbicides to prevent

 the regrowth of vegetation.

Then, for 3 years, they compared outflow of water and nutrients in this

experimental site with those in the control site

The scientists found that, with no plants to help absorb and retain water,

the amount of water flowing out of the deforested valley increased by 30-40%.

 As this excess water ran rapidly over the ground, it eroded soil and carried

 dissolved nutrients out of the topsoil in the deforested site.

Overall, the loss of key soil nutrients from the experimental forest was six

 to eight times that in the nearby uncut control forest.

Characteristics of reliable science

Reliable science consists of data, hypotheses, models, theories, and

laws that are widely accepted by all of most of the scientists who

are considered experts in the field under study

Difference between Positive and Negative feedback

A pos feedback loop causes a system to change further in same direction

A neg feedback loop is corrective, causing change in the opposite direction

“Ecological tipping point”

Point at which an environmental problem reaches a threshold level,

which causes an often-irreversible shift in the behavior of a natural system

Chapter 7

Factors that influence climate

Elevation or altitude, prevailing global wind patterns, latitude and angles

 of the sun rays, topography, effects of geography, and surface oft he earth

El Nino and their effects

El Nino-Southern Oscillation, or ENSO- is an example of the

 interaction of air and land.

Large-scale weather phenomenon occurring every few years

when prevailing winds in the tropical Pacific Ocean weaken

 and change direction

Above-average warming of Pacific waters can affect populations

 of marine species by changing the distribution of plant nutrients

Trade winds- winds that blow from east to west

How climate affects the nature and location of biomes on earth

Climate helps to determine where organisms can live

Precipitation and temperature lead to the formation of tropical (hot),

temperatre(moderate) and polar(cold) desesrts, grasslands, and forests

Climate and cegetation vary with latitude and elevation

Biomes are large regions, each characterized by certain types of

climate and dominant plant life

Biomes are not uniform. They consist of a mosaic of patches, each

with somewhat different biological communities but with similarities

typical of the biome

3 types of deserts

Tropical deserts such as the Sahara and the Namib of Africa are

hot and dry most of the year. They have few plants and a hard,

windblown surface strewn with rocks and sand.

In temperate deserts, daytime temperatures are high in summer

 and low in winter and there is more precipitation than in tropical

deserts. The sparse vegetation consists mostly of widely dispersed,

drought-resistant shrubs and cacti or other succulents adapted to

the dry conditions and temperature variations

In cold deserts, such as the Gobi Desert in Mongolia, vegetation is

 sparse. Winters are cold, summers are warm or hot, and precipitation is low.

In all types of deserts, plants and animals have evolved adaptions

that help them to stay cool and to get enough water to survive.

3 types of grassland

Tropical Grassland (or Savanna) is usually warm year-round with

alternating dry and wet seasons

Temperate grassland – winters can be very cold, summers are hot

and dry, and annual precipitation is sparse and falls unevenly though

the year and it contains the world’s most fertile soils

Examples: short-grass and tall-grass prairies

Cold Grasslands (or arctic tundra) are bitterly cold and treeless plains

Permafrost forms when frozen underground soil exists for more

than two consecutive years

3 types of forests

Tropical rain forests are found near the equator, where hot, moisture-laden

air rises and dumps its moisture

Dominated by broadleaf evergreen plants keep most of their leaves

year-round. There is little vegetation on the forest floor because the

dense tree-top canopy blocks most light from reaching the ground.

Very high net primary productivity and an incredible high level of

biological diversity

Cover about 2% of the earth’s land surface but are estimated to

contain at least 50% of the earth’s known terrestrial plant and animal species

Temperate Deciduous forest

Broadleaf deciduous trees include oak, hickory, maple, aspen, and birch

Cool temperatures and slow decomposition result in a thick layer

of slowly decaying leaf litter which is a storehouse of nutrients (humus)

Northern Coniferous Forest (Boreal Forest/Taiga)

Winters are long and extremely cold

Plant diversity is low, decomposition is slow

Soils are acidic, nutrient-poor

Characteristics of the tundra

One outcome of the extreme cold is the formation of permafrost

which is the underground soil in which captured water stays

frozen for more than two consecutive years. Tundra soils are

usually nutrient poor and because of the short growing season,

tundra soil and vegetation recover very slowly from damage of disturbance

Characteristics of mountains

Mountains are steep or high-elevation lands where dramatic

changes in altitude, slope, climate, soil, and vegetation take

place over a very short distance. Many mountains are islands of

biodiversity surrounded by a sea of lower-elevation l

andscapes transformed by human activities

Important ecological roles include:

- Contain the majority of the world’s trees

- Provide habitats for endemic species

- Have sanctuaries for species that can migrate and surviving

in higher altitudes if they are driven from lowlands by human

activities or warming climate

- They serve as major storehouses of water

Characteristics of chaparral

Mild, wet winters, and hot dry summers

Most of the plants have small, hard leaves which hold moisture

Poison oak, scrub oak, Yucca Wiple and other shrubs, trees, and cacti

Characteristic of the polar zones

Harsh environments covered in snow and ice

Long winters and short summers

Snow storms and cold winds for much of the year

Difference between oligotrophic and eutrophic bodies of water

Oligotrophic (poorly nourished) lakes have small supply of

 plant nutrients, causing them to look crystal clear

Eutrophic (well-nourished) lakes have a large supply of

nutrients needed by producers, causing them have high

 productivity and look murky brown or green

Cultural eutrophication occurs when human inputs of nutrients

 from the atmosphere and from nearby urban and agricultural

areas accelerate eutrophication

Major types of wetlands

Inland wetlands are lands located away from coastal areas that

are covered with freshwater or part of the time- excluding lakes,

reservoirs, and steams

This includes marshes, swamps, bogs, prairie pothole, and fens

Some wetlands are covered with water year-round and other

remain under water for only a short time each year

Marine Ecosystems and how human activities are threatening them

Mainre ecosystems can be divided into

1. Coastal waters, 2. Open ocean, 3. Estuaries, and 4. Coral reefs

Great Pacific Garbage patch

*go back to Chapter 11 because it was already mentioned*

How climate change is impacting coral reefs and why it is occurring

Coral reefs are storehouse of biodiversity

Act as a natural barrier that help to protect 15% of the world’s coastlines

from erosion caused by waves and storms

Provide habitats for about 25% of all marine organisms

Produce about 10% of the global fish catch

Provide fishing and ecotourism jobs for some of the world’s poorest countries

Coral reefs are easily damaged because they grow slowly, are disrupted

easily and require specific water conditions

Coral bleaching occurs when stressed such as increased temperature

 cause the symbiotic zooxanthellae to die. Without food, the coral polyps

die, leaving behind a white skeleton of calcium carbonate. Ocean water is

becoming more acidic as it absorbs some of excess carbon dioxide from

 the atmosphere. The CO2 reacts with ocean water to from a weak acid,

which can slowly dissolve the calcium carbonate that makes up the corals

Chapter 4

Four components of biodiversity and why they are important

1. Species diversity, the number and variety of the species present

 in any biological community, is the most obvious component of biodiversity

2. Genetic diversity, the variety of genes found in a population or in a

 species, which enable the earth’s species to survive and adapt to

dramatic environmental changes

3. Ecosystem diversity – the earth’s variety of desert, grasslands,

forests, mountains, oceans, lakes, rivers, and wetlands- is another

major component of biodiversity

4. Functional diversity- the variety of processes such as energy

flow and matter cycling that occur within ecosystems as species

interact with one another in food chains and food webs

What are biomes and how they occur?

Biomes are a terrestrial region distinguished by the predominance

of certain types of vegetation and other forms of life

E.O. Wilson and his contributions to biodiversity

He became one of the world’s experts on ants and then steadily

widen his focus, eventually to include the entire biodiversity

published The Diversity Of Life, presenting the principles and practical

issues of biodivesity

What will happen if biodiversity continues to decrease?

The earth’s biodiversity is a vital part of the natural capital on which

 we depend. We use the earth’s biodiversity as a source of food,

medicine, building materials, and energy.

Also, provides critical ecosystem services such as air and water

purification and the earth’s variety of species and ecosystems serve as

raw materials for the evolution of new species and ecosystem services

 in response to changing environmental conditions.

Native species, non-native species, indicator species, and keystone species

Native species – the species that normally live and thrive in a

particular ecosystem

Non-native species – immigrate into, or are deliberately or

accidentally introduced, into an ecosystem

Can threaten native species through competition for resources,

reducing the number of native species

Can spread rapidly if they find a favorable niche

Indicator species – species that provide early warnings of

environmental change in a community or an ecosystem

Some amphibian species are good indicator species – their

extinction in Central and South American tropical forests has

been tied to climate change

Keystone species – species whose roles have a large effect on

the types and abundance of other species in an ecosystem

May cause population crashes and extinction of dependent

species if drawn to extinction itself

Roles of sharks and alligators as keystone species

Alligators – the American alligator, a keystone species of

subtropical wetland ecosystems

Alligators dig deep depressions, or gator holes

These depressions hold freshwater during dry spells, serve

as refuges for aquatic life, and supply freshwater and food

 for fishes, insects snakes, turtles, birds, and other animals

The large nesting mound that alligators build provide nesting

 and feeding sites for some herons and egrets, and red-bellied

 turtles lay their eggs in old gator nests and they also eat large

numbers of gar, a predatory fish, which maintain populations

of game fish such as bass and bream that the gar eat

Almost hunted to extinction – so much that it was placed on

the endangered species list (today, it has recovered and been

 removed from the list)

Sharks that feed at or near the tops of their food webs

remove injured and sick animals from the ocean. Without

this free ecosystem service, the oceans would be teeming

 with dead and dying fish and marine mammals

Natural selection and how does it cause evolution

Natural selection explains how life on earth changes over

time due to changes in the genes of populations

In this process, individuals with certain genetic traits are

more likely to survive and reproduce under a particular set

of environmental conditions, and to pass these traits on to

 their offspring, than are individuals without these traits

Theory of evolution by natural selection

Explains how life on earth changes over time due to changes

in the genes of populations

Population evolution occurs through gene mutation

Gives individuals genetic traits that enhance their ability to

 survive and produce offspring

How mutations relate to evolution and natural selection

Some are random; often occur by exposure to radioactivity,

ultraviolet radiation, and chemicals (mutagens)

Genetic changes in reproductive cells are inherited by offspring (heritable traits)

Some heritable trains give individuals advantage that improve

 their ability to survive and reproduce (adaptive traits)

What genetic adaptions have helped humans become

such powerful species?

We have used artificial selection to change the genetic

 characteristics of populations with similar genes

In this process, we select one or more desirable genetic

 traits in the population of a plant or animal such as a

type of wheat, fruit, or dog

Then we use selective breeding, or crossbreeding, to generate

populations of the species containing large numbers of individuals

with the desired traits

How do new species form?

Speciation occurs when one species splits into two or more

different species

Species are considered different when individuals can no longer

breed and reproduce fertile offspring

What is extinction?

Extinction is complete disappearance of a species from the earth.

 It happens when a species cannot adapt and successfully reproduce

 under new environmental conditions, when a species evolves into

one or more new species, or when all the species’ individuals are

 killed off by forces in the environment

Endemic species and why they are so vulnerable to extinction

Endemic species are species that are found in only one area making

it difficult for them to migrate or adapt during rapidly changing

 environmental conditions

Many endangered endemic species are amphibians

Why is the rate of extinction increasing?

Large group of species (25-95% of all species) are wiped out,

primarily because of major, widespread environmental changes

Fossil and geological evidence indicate that there have been

at least three and probably five mass extinctions (at intervals of

20-60 million years) during the past 500 million years