IB ESS REVISION (EXAM) NOTES
TOPIC 1: Systems and Models
Systems:an assemblage of parts and their relationship forming a
functioning entirety or wholeo Open systems: exchanges matter and
energyo Closed systems: exchanges only energyo Isolated systems:
neither matter nor energy and is theoretical
Laws of thermodynamicso 1st: energy is neither created nor
destroyed, only changes formso 2nd: the entropy of a closed system
increases; when energy is transformed into work, some energy is
always lost as waste heat
EquilibriumoSteady-state: in open systems, continuous inputs and
outputs of energy and matter, system as a whole remains in a
constant state, no long term changes.o Static: no change over time;
when the state of equilibrium is distributed, the system adapts a
new equilibrium; cant occur in living systemso Stable: the system
returns to the same equilibrium after disturbanceso Unstable:
system returns to a new equilibrium after disturbances
Feedbacko Positive: results in a further decrease of output and
the system is destabilized and pushed into a new state of
equilibriumo Negative: tends to neutralize or counteract any
deviation from an equilibrium and tends to stabilize
systemsTransfers and transformationso Transfers:- The movement of
material through living organisms- Movement of material in
non-living process- The movement of energyo Transformations- Matter
to matter- Energy to energy- Matter to energy- Energy to matter
The Gaia modelo Views earth as a living organismo The earth has
a disease
TOPIC 2: Ecosystems
Definitions: Biotic factors: living components Abiotic factors:
non-living physical and chemical components Species: a particular
type of organism Population: a group of individuals of the same
species living in the same area at the same time Habitat: the
environment where a species normally lives Ecological niche: how an
organism makes a living Community: a group of populations living
and interacting with each other in a common habitat Ecosystem: a
community of independent organisms (biotic factors) and the
physical environment (abiotic factors) which they inhabit Biome: a
collection of ecosystems sharing common climatic conditions
Respiration: a process of breaking down food in order to release
energy Photosynthesis: a process of producers making their own food
(glucose) and producing oxygen from water and carbon dioxide
Biomass: the living mass of an organism or organisms but sometimes
refers to dry mass Gross Productivity: the total gain in energy or
biomass per unit area per unit time o GPP: by producers o GSP: by
consumers Net Productivity: the total gain in energy or biomass per
unit area per unit time after allowing for losses to respiration o
NPP: by producers o NSP: by consumersBiomes: climate latitude
(distance from equator) altitude (height above sea level) wind and
water currents P/E ratio (precipitation over evaporation
ratio)latent heat: heat that is either taken in or produced when
water changes from state to stateDifferent Biomes: Tropical
Rainforest hot and wet areas with broadleaved ever green forest.
Within 50 north or south of the equator. High rainfall and high
temperature, high insolation as near equator. There are amazingly
high levels of biodiversity, many species and many individuals of
specie. There are very large evergreen trees, small shrubs,
orchids.It is estimated that tropical rainforest produces 40% of
NPP of terrestrial ecosystems. But the problems it has, are that
50% of human population live near the equator, so they damage the
biome, they are exploited for human economical needs.
Desert dry areas which are usually hot in the day and cold in
the night, there are tropical, temperate and cold deserts. It
covers 20-30% of earths surface, about 300 of north or south of the
equator. Water is limited in the deserts. There are few species and
very low biodiversity, there are only the ones who adapted to the
conditions. Soil can be rich, because the nutrients are not washed
away from the water. NPP is low because the amount of plants and
animals are limited, because of the water. Desertification is the
human activity. Temperate Grassland fairly flat areas, that are
covered with grass, they are located 400 600 from the equator,
either north or south. The net productivity is not very high,
because its only grass that grows on the land, nothing else. And
with that the animals that are growing are small size as well.
Humans use grass lands for the crops. Temperate Forest -mild
climate and deciduous forest. Located 400 600 north or south of the
equator, it has 4 seasons, there also are fewer species than
tropical rainforest, it has the second highest NPP after the
tropical rainforest. Much of the temperate forests, have been
cleared because of human activities. Arctic Tundra Tree less plain
with permafrost, cold and very low precipitation, dark nights. It
is 10% of lands surface, it is located on the arctic cap. Water is
limiting but the fire can stop the climax community forming. There
are no trees but there Is a thick mat, covered by mosses and
grasses. It has very low biodiversity, and soil is poor. With that
the NPP is very low, humans use it for mining.Ecosystem
Structure:
Food chains and trophic levels food chain: shows a flow of
energy from one organism to the next food web: shows a complex
network of interrelated food chains trophic level: a position that
an organism or a group of organisms in a community occupies in a
food chain producers or autotrophs: which manufacture their own
food from inorganic substances consumers or heterotrophs: which
feed on autotrophs or other heterotrophs to obtain energy
decomposers: consumers that obtain energy from dead organisms
detritivores: consumers that derive their food from detritus or
decomposing organic materialEcological pyramids o pyramid of
numbers: shows the number of organisms at each trophic level in a
food chain advantages: o easy method of giving an overview o good
for comparing changes in population numbers over different times
disadvantages: o all organisms included regardless of their size o
numbers can be too great to represent accurately o pyramid of
biomass: contains the biomass at each trophic level advantages:
overcomes the problems of pyramids of numbers disadvantages: only
uses samples from populations, so its impossible to measure biomass
exactly organisms must be killed to measure dry mass o pyramid of
productivity: contains the flow of energy through each trophic
level; shows the energy being generated and available as food to
the next trophic level during a fixed period of time advantages:
shows the actual energy transferred and allows for rate of
production disadvantages: very difficult and complex to collect
energy data as the rate of biomass production over time is required
o bioaccumulation and biomagnification bioaccumulation: increase in
concentration in one organism over time biomagnification: increase
in concentration with the increase in trophic levels o trophic
efficiency: only 10% of the energy is transferred to the next, so
the trophic efficiency=10%
Population Interactions A population is a group of organisms of
the same species living in the same area at the same time and
capable of interbreeding. Population density is the average number
of individuals in a stated area.
Competition Competition between members of the same species
isIntra-specificcompetition. Individuals of the different species,
competeting for the same resource is calledInter-specific
competition. The other outcome is that one species may totally
outcompete the other, this is the principle of Competitive
exclusion.
Predation happens when one animal, the predator, eats another
animal, the prey.Herbivory is defined as an animal eating green
plant.Parasitism - is a relationship between two species in which
one species lives in or on another gaining its food from
it.Mutualism- s a relationship between two or more species in which
both or all benefit and none suffer.
Succession Succession is the change in species composition in an
ecosystem over time It may occur on bare ground where soul
formation starts the process or where no soil has already formed,
or where the vegetation has been removed. Early in succession, GPP
and respiration are low and so NPP is high as biomass
accumulates.
To see the stages of primary succession go to page 266. Table
14.1
Primary succession involves the colonization of newly created
land by organisms.See Fig. 14.1 on page 266.
Primary succession starts on dry land is called axerosere. A
succession in water is ahydrosere.See Fig. 14.2 on page 267
Succession progresses in stages from pioneer species, that are
adapted to live in limiting environments, to stable developed
community. This final community is termed a climax community.
To see the secondary succession process in time, go to page 268
and find Fig. 14.3
Secondary succession occurs on souls that are already developed
and ready to accept seeds carried in by the wind. Also there are
often dormant seeds left in the soil from previous community. This
shortens the number of seral stages the community goes through.
Changes occurring during a succession (refer to Fig. 14.4 on
page 268) the size of organisms increases energy flow becomes more
complex soil depth, humus, water-holding capacity, mineral content
and cycling increase Biodiversity increases and then falls as the
climax community is reached NPP and GPP rise and then fall
Production: respiration ratio fallsSpecies diversity in
successions
Early stages of succession: few species Species diversity
increases with the succession Increase continues until a balance is
reached between possibilities for new species to establish,
existing species to expand their range and local extinction
TOPIC 3: Human Population, Carrying Capacity and Resource
Use
Population dynamics
Exponential growth or geometric growthWhen the population is
growing, and there are no limiting factors slowing the growth.
Density-dependent limiting factors (biotic factors when effects
depend on the population density) Negative feedback mechanism- lead
to stability of the populationInternal factors act within species1.
Limited food supply lead to intraspecific competition2. Lack of
suitable territory3. Survival of the fittestExternal factors act
between different species (predation and disease)1. Predation pray
animals increase, predators increase -> pray decreases and the
predators decrease2. Disease at high populations spreads
fastS-curvesThe visual picture of the curves
Start with exponential growth Then the growth slows down Finally
constant sizeOther facts: Consistent with carrying capacity of the
environment Environmental resistance
Density-independent limiting factors (abiotic factors when
effects do not depend on the population density) Climate Weather
Volcanic eruptions Floods
J- curves Boom and bust population grows exponentially and
suddenly collapses The collapse is referred to as overshoot The
sudden collapse usually caused by abiotic factors The J-curves
usually occur in:1. Microbes2. Invertebrates3. Fish4. Small
mammals
K-and r-selected species
K-selected species
Long life Slower growth Late maturity Fewer large offspring High
parental care and protection High investment in individual
offspring Adapted to stable environment Later stages of succession
Niche specialists Predators Regulated mainly by internal factors
Higher trophic level Trees, albatrosses, humans
r-selected species
Short life Rapid growth Early maturity Many small offspring
Little parental care or protection Little investment in individual
offspring Adapted to unstable environment Pioneers, colonizers
Niche generalists Prey Regulated mainly by external factors Lower
trophic level Examples: annual plants, flour beetles, bacteria
K-and r-selected species are extremes of a continuum. Many
species are mixture of both characteristics.
Demographics study of the dynamics of the population
change.Human Development Index measure:1. Life expectancy2. Well
being3. Standards of living4. GDP
MEDC- industrialized nations with high GDPs.LEDC- less
industrialized nations with lower GDP
Population growth effects on the environmentMore people- more
recourses- more waste- greater impact
Factors that affect population size:
Crude birth rate number of births per thousand individuals in
population per yearCrude death rate the number of deaths per
thousand individuals in a population per year. Immigration
EmigrationNatural increase rate(crude birth rate crude death rate)
/ 10, which, gives the natural increase rate as a percentage. It
excludes the effects of migration.Total fertility rate the average
number of children each woman has over her lifetime.Fertility rate
the number of births per thousand women of childbearing age. In
reality,replacement fertilityranges from 2.03 in MEDCs to 2.16 in
LEDCs because of infant and childhood mortality. (Fertility is
sometimes considered a synonym for the birth rate)
Human population growthDemography is the study of the
statistical characteristics of human populations, e.g. total size,
age and sex composition ad changes over time with variations in
birth and death rates.
Carrying capacity the maximum number of a species or load that
can be sustainably supported by a given environment, without
destroying the stock Populations remainstable when birth rate =
death rate The size of the population is depended on the wealth of
the population Demand for and the exchange of the resources effects
the size All of the abovediffers in MEDCs and LEDCs
Population growth and food shortages
There are two main theories relating to population growth and
food supply, from Malthus and Boserup
Malthusian theory
Thomas Malthus English clergyman and economist (1766 to 1834)
Published an essay on the principle of population in 1798 Claimed
that food supply was the main limit to population growth Believed
that human population increases geometrically, whereas food
supplies grows arithmetically, and as a result, there are much more
humans than food supplies
Limitations of Malthusian theory
Too simplistic Shortage of food is just one possible explanation
for the slowing in population growth It is only poor who go hungry
Globalization is something Malthus could not have expected
Boserup theory
Ester Boserup, a Danish economist (1965) Increase in population
would stimulate technologists to increase food production Rise in
population will increase the demand for food and so act as an
incentive to change agrarian technology and produce more food
Belief that necessity is the mother of invention
Limitations of Boserups theory
Too simplistic view Like Malthus, his idea is based on the
assumption of a closed community. Emigration and immigration are
not considered Overpopulation can lead to unsuitable faming
Family sizes
Appears that decision to have children is not correlated with
GNP of a country nor personal wealth: High infant and childhood
mortality Security in old age Children are an economic asset in
agricultural societies Status of women Unavailability of
contraception
The ways to reduce the family size are to:
Provide education Improve health Provide contraception Increase
family income Improve resource management
Population Pyramids
These pyramids show how many individuals are alive in different
age groups (five-year cohorts) in a country for any given year.
They also show the frequency of males and females. In the pyramids,
population numbers are on the x-axis and the age groups on the
y-axis.
The shapes of the pyramids are following:
Expanding (stage 1) high birth rates; rapid fall in each upward
age group due to high death rates; short life expectancy.
Expanding (stage 2) high birth rates; fall in death rates as
more living to middle age; slightly longer life expectancy.
Stationary (stage 3) declining birth rate; low death rate more
people living to old age.
Contracting (stage 4) low birth rate; low death rate; higher
dependency ratio; longer life expectancy.
Demographic transition model:
Demographic transition model describes the pattern of decline in
mortality and fertility (natality) of a country as a result of
social and economic development.
This model can be described as a five-stage population model,
which can be linked to the stages of the sigmoid growth curve.The
stages are:Pre- industrial society: High birth rate due to no birth
control; High infant mortality rates; Cultural factors encouraging
large families. High death rates due to disease, famine, poor
hygiene and a little medicine.LEDC: Death rate drops as sanitation
and food improve, Disease is reduced so lifespan increases. Birth
rate is still high so population expands rapidly Child mortality
falls due to improved medicine.Wealthier LEDC: Birth rats fall due
to access to contraception. Improved health care, education and
emancipation of women. Population begins to level off and desire
for material goods and low infant death rates mean that people have
smaller families.MEDC: Low birth rates Low death rates
Industrialized countries Stable population sizesMEDC: Population
may not be replaces as fertility rate is low. Problems of aging
workforce.
Food Resources
Undernourishment, malnourishment Lack of essential nutrients
like proteins, vitamins, minerals.
Agriculture
Types of farming systems
Subsistence farming the provision of food by farmers for their
own families or the local community
Cash cropping- growing the food for the market
Commercial farming- large, profit- making scale maximizing
yields per hectare. (monoculture)One type of crop or animal is
produced.
Extensive farming more land with lower density of stocking or
planting and lower inputs and corresponding outputs.
Intensive farming using the land more intensively with high
levels of input and output per unit area.
Pastoral farming raising animals on a land which is not suitable
for crops.
Arable farming is sowing crops on good soils to eat directly or
to feed to animals
Mixed farming has both animals and crops and is a system in
itself where animals waster is used to fertilize the crops and
improve soil structure.
Farmings energy budget
A system with inputs, outputs, storages and flows = marketable
product sold by weight
Energy balance in farming = fuel, labor, any other energy, soil,
sow the seed, harvest the crop, prepare and package, transport,
energy cost of dealing with waster products.
Grain equivalent the quantity of wheat grain that would have to
be used to produce one kg of that product.
Rice Production in Borneo
Traditional, extensive rice production in Indonesian Borneo- Low
inputs of energy and chemicals, high labor intensity and a low
productivity.- No fertilizers and pesticides used- Rice yield is
only output (no pollution)
Intensive rice production in California- high inputs of energy
and chemicals, low labor intensity and a high productivity- diesel
and petrol- fertilizers (N, P) Pesticides (insecticides and
herbicides)- More energy input than output- More pollution
Fisheries industrial hunting
According to FAO more than 70% of the worlds fisheries are fully
exploited, in decline or seriously depleted.The global fish catch
is in decline even though technology has improved.Demand is high
and rising but fisherman cannot find or catch enough fish because
they are no longer there
The tragedy of the commons - Tension between the common good and
the needs of the individual and how they can be in conflict.
Exploitation of the oceans is the tragedy of the commons
The Grand Banks off the coast of Newfoundland were once among
the richest fishing grounds on Earth. Since 1400s its been depleted
by various countries.
The United Nations Convention on Law of the Sea (UNCLOS)
international agreement written over decades that attempts to
define the rights and responsibilities of nations with respect to
the seas and marine resources.
Maximum Sustainable Yield (MSY)
Sustainable Yield increase in natural capital
Sustainable yield of the aquifer is the amount that can be taken
each year without permanently decreasing the amount of water
stored.
SY = annual growth and recruitment annual death and
immigration
Harvesting MSY leads to population decline and thus loss of
resource base and an unsustainable industry or fishery.
Optimal Sustainable Yield (PSY) half the carrying capacity.
Safety margin than MSY ut still may have an impact on population
size with other environmental impacts.
Resources- Natural CapitalNatural Capital - Natural resources,
services that support life, natural processes. The Goods and
services that are not manufactured but have value to humans.
Natural Income (yield, harvest, services) Yield from the natural
capital.Renewable Resources living resources that can replace or
restock themselves. (Alternative energy resources)Non-renewable
resources- exist in finite amounts on Earth and are not renewed or
replaced after they have been used or depleted. (Minerals and
fossil fuels)Replenishable Resources replaceable but take long
period of time. (Groundwater)Sustainability living within the means
of nature, on the interest or sustainable natural income generated
by natural capital.
Tragedy of commons- many individuals who are acting in their own
self-interest to harvest a resource may destroy the long-term
future of that resource so there is none for anyone.Resource
Values
Economic marketable goods and services Ecological- life-support
services Scientific/technological - applications Intrinsic
aesthetic, cultural, spiritualUrbanization the drifts from the
countryside to urban life. Urbanization might eventually encroach
on or degrade natural habitats of the cities.Globalization- Every
society on Earth is connected and unified into a single functioning
entity. (Global trade) Globalization often leads to westernization.
Globalization has facilitated the process of global agreements on
global issues.
Human Carrying Capacity Maximum number or load of individuals
that an environment can sustainably carry or support.
Ecocentric - reduce the use of non-renewable resources and
minimize their use of renewable ones.
Technocentric human carrying capacity can be expanded
continuously through technological innovation and development.
Conventional Economists trade and technology increase the
carrying capacity.Ecological Economists technological innovation
can only increase the efficiency with which natural capital is
used.Reuse- object is used more than once. (Drink bottles, second
hand cars)Recycling objects material is used again to manufacture a
new product. (Aluminium)Remanufacturing objects material is used to
make a new objects of the same type. (Plastic bottles)Absolute
Reductions use fewer resources (energy, paper)Ecological footprint
area of land that would be required to sustainably provide all of a
particular populations resources and assimilate all its wastes.
Population dynamics
Exponential growth or geometric growthWhen the population is
growing, and there are no limiting factors slowing the growth.
Density-dependent limiting factors (biotic factors when effects
depend on the population density) Negative feedback mechanism- lead
to stability of the populationInternal factors act within species1.
Limited food supply lead to intraspecific competition2. Lack of
suitable territory3. Survival of the fittestExternal factors act
between different species (predation and disease)1. Predation pray
animals increase, predators increase -> pray decreases and the
predators decrease2. Disease at high populations spreads
fastS-curvesThe visual picture of the curves
Start with exponential growth Then the growth slows down Finally
constant sizeOther facts: Consistent with carrying capacity of the
environment Environmental resistance
Density-independent limiting factors (abiotic factors when
effects do not depend on the population density) Climate Weather
Volcanic eruptions Floods
J- curves Boom and bust population grows exponentially and
suddenly collapses The collapse is referred to as overshoot The
sudden collapse usually caused by abiotic factors The J-curves
usually occur in:1. Microbes2. Invertebrates3. Fish4. Small
mammals
K-and r-selected species
K-selected species
Long life Slower growth Late maturity Fewer large offspring High
parental care and protection High investment in individual
offspring Adapted to stable environment Later stages of succession
Niche specialists Predators Regulated mainly by internal factors
Higher trophic level Trees, albatrosses, humans
r-selected species
Short life Rapid growth Early maturity Many small offspring
Little parental care or protection Little investment in individual
offspring Adapted to unstable environment Pioneers, colonizers
Niche generalists Prey Regulated mainly by external factors Lower
trophic level Examples: annual plants, flour beetles, bacteria
K-and r-selected species are extremes of a continuum. Many
species are mixture of both characteristics.
Demographics study of the dynamics of the population
change.Human Development Index measure:1. Life expectancy2. Well
being3. Standards of living4. GDP
MEDC- industrialized nations with high GDPs.LEDC- less
industrialized nations with lower GDP
Population growth effects on the environmentMore people- more
recourses- more waste- greater impact
Factors that affect population size:
Crude birth rate number of births per thousand individuals in
population per yearCrude death rate the number of deaths per
thousand individuals in a population per year. Immigration
EmigrationNatural increase rate(crude birth rate crude death rate)
/ 10, which, gives the natural increase rate as a percentage. It
excludes the effects of migration.Total fertility rate the average
number of children each woman has over her lifetime.Fertility rate
the number of births per thousand women of childbearing age. In
reality,replacement fertilityranges from 2.03 in MEDCs to 2.16 in
LEDCs because of infant and childhood mortality. (Fertility is
sometimes considered a synonym for the birth rate)
Human population growthDemography is the study of the
statistical characteristics of human populations, e.g. total size,
age and sex composition ad changes over time with variations in
birth and death rates.
Carrying capacity the maximum number of a species or load that
can be sustainably supported by a given environment, without
destroying the stock Populations remainstable when birth rate =
death rate The size of the population is depended on the wealth of
the population Demand for and the exchange of the resources effects
the size All of the abovediffers in MEDCs and LEDCs
Population growth and food shortages
There are two main theories relating to population growth and
food supply, from Malthus and Boserup
Malthusian theory
Thomas Malthus English clergyman and economist (1766 to 1834)
Published an essay on the principle of population in 1798 Claimed
that food supply was the main limit to population growth Believed
that human population increases geometrically, whereas food
supplies grows arithmetically, and as a result, there are much more
humans than food supplies
Limitations of Malthusian theory
Too simplistic Shortage of food is just one possible explanation
for the slowing in population growth It is only poor who go hungry
Globalization is something Malthus could not have expected
Boserup theory
Ester Boserup, a Danish economist (1965) Increase in population
would stimulate technologists to increase food production Rise in
population will increase the demand for food and so act as an
incentive to change agrarian technology and produce more food
Belief that necessity is the mother of invention
Limitations of Boserups theory
Too simplistic view Like Malthus, his idea is based on the
assumption of a closed community. Emigration and immigration are
not considered Overpopulation can lead to unsuitable faming
Family sizes
Appears that decision to have children is not correlated with
GNP of a country nor personal wealth: High infant and childhood
mortality Security in old age Children are an economic asset in
agricultural societies Status of women Unavailability of
contraception
The ways to reduce the family size are to:
Provide education Improve health Provide contraception Increase
family income Improve resource management
Population Pyramids
These pyramids show how many individuals are alive in different
age groups (five-year cohorts) in a country for any given year.
They also show the frequency of males and females. In the pyramids,
population numbers are on the x-axis and the age groups on the
y-axis.
The shapes of the pyramids are following:
Expanding (stage 1) high birth rates; rapid fall in each upward
age group due to high death rates; short life expectancy.
Expanding (stage 2) high birth rates; fall in death rates as
more living to middle age; slightly longer life expectancy.
Stationary (stage 3) declining birth rate; low death rate more
people living to old age.
Contracting (stage 4) low birth rate; low death rate; higher
dependency ratio; longer life expectancy.
Demographic transition model:
Demographic transition model describes the pattern of decline in
mortality and fertility (natality) of a country as a result of
social and economic development.
This model can be described as a five-stage population model,
which can be linked to the stages of the sigmoid growth curve.The
stages are:Pre- industrial society: High birth rate due to no birth
control; High infant mortality rates; Cultural factors encouraging
large families. High death rates due to disease, famine, poor
hygiene and a little medicine.LEDC: Death rate drops as sanitation
and food improve, Disease is reduced so lifespan increases. Birth
rate is still high so population expands rapidly Child mortality
falls due to improved medicine.Wealthier LEDC: Birth rats fall due
to access to contraception. Improved health care, education and
emancipation of women. Population begins to level off and desire
for material goods and low infant death rates mean that people have
smaller families.MEDC: Low birth rates Low death rates
Industrialized countries Stable population sizesMEDC: Population
may not be replaces as fertility rate is low. Problems of aging
workforce.
EnergyResources
Source sun. Fossil fuels are sources of stored energy from the
sun Oil is the economys largest source at the moment, supplying 37%
of all the energy we use. Coal is the next largest, supplying 25%
Natural gas supplying 23%
How much longer for fossil fuels?
The common estimates include: Oil 50 years Natural gas 70 years
Coal - 250 years Will eventually run out, as they are non-renewable
energy sources.
Depends on: Our rate of use Technologies Efficiency of humans
How successful humans are at finding new sources How successful
humans are at finding and extracting more. If the wealth of humans
increase The population of humans Demand increase or decrease
Evaluation of energy sources and their advantages and
disadvantages
Non-renewable
Coal (fossil fuel)
From Fossilized plants laid down in the carboniferous period
Mined from seams of coal which are in strata between other types of
rock May be open cast mined (large pits) or by tunnels underground.
Burnt to provide heat directly or electricity by burning to
turbines in power stations.
Advantages Plentiful supply Easy to transport and solid Needs no
processing Relatively cheap to mine and convert to energy by
burning Up to 250 years of coal leftDisadvantages
Non-renewable energy source Cannot be replaced once used (same
for oil and gas) Burning releases carbon dioxide which is a
greenhouse gas Some coals contain up to 10% sulfur. Burning sulfur
forms sulfur dioxide which causes acid deposition Particles of soot
from burning coal produce smog and lung disease. Coal mines leave
degraded land and pollution. Lower heat of combustion than other
fossil fuels (less energy released per unit mass)
Oil (fossil fuel)
From Fossilized plants and micro-organisms that are compressed
to a liquid and found in porous rocks Crude oil is refined by
fractional distillation to give a variety of products from lighter
jet fuels and petrol to heavier diesel and bitumen. Extracted by
oil wells. Many oil fields are under the oceans so extraction is
dangerous Pipes are drilled down to the oil-bearing rocks to pump
the oil out. Most of the world economy runs on oil either burnt
directly in transport and industry or to generate electricity
Advantages High heat of combustion Many uses Once found is
relatively cheap to mine Easily converted into energy
Disadvantages Only a limited supply May run out in 20-50 years
Gives off carbon dioxide when burned Oil spill danger from tanker
accidents. Risk of terrorism in attacking oil pipes Greenhouse gas
effect
Natural gas (fossil fuel)
From Methane gas and other hydrocarbons trapped between seams of
rock Extracted by drilling like crude oil Often found with crude
oil Used directly in homes for domestic heating and cooking
Advantages Highest heat of combustion Lot of energy gained from
it Ready- made fuel Relatively cheap form of energy Cleaner fuel
than coal and oil
Disadvantages Only limited supply of gas but more than oil About
70 years left (according to current usage) Gives off carbon dioxide
but only half as much per unit of energy produced as coal
Nuclear fission
From Uranium is the raw material. This is a radioactive and is
split in nuclear reactors by bombarding it with neutrons As it
splits into plutonium and other elements, massive amounts of energy
are also released Uranium is mined Australia has the most known
reserves Canada exports the most Other countries have smaller
amounts About 80 years worth left to mine at current rates Could be
extracted from sea water
Advantages Raw materials are relatively cheap once the reactor
is built and can last quite a long time Small mass of radioactive
material produces a huge amount of energy No carbon dioxide
released nor other pollutants (unless there are accidents)
Disadvantages Extraction costs high. Nuclear reactors are
expensive to build and run Nuclear waste is still radioactive and
highly toxic Big question of what to do with it Needs storage for
1000s of years May be stored in mine shafts or under the sea
Accidental leakage of radiation can be devastating. Accidents are
rare but worst nuclear reactor accident at Chernobyl, Ukraine was
in 1986 Risk of uranium and plutonium being used to make nuclear
weapons
Renewable
Hydroelectric power (HEP)
From Energy harnessed from the movement of water through rivers,
lakes and dams to power turbines to generate electricity
Pumped-storage reservoirs power turbines
Advantages High quality energy output compared with low quality
energy input Creates water reserves as well as energy supplies.
Reservoirs used for recreation, amenity Safety record is good.
Disadvantages Costly to build Can cause the flooding of
surrounding communities Dams have major ecological impacts on local
hydrology Silting of dams Downstream lack of water Risk of flooding
if dam bursts
BiogasFrom Decaying organic plant or animal waste are used to
produce methane in biogas generators or burnt directly as
dung/plant material More processing can give oils which can be used
as fuel in vehicles instead of diesel fuel = biofuels
Advantages Cheap Available If the crops are replanted, biogas
can be a long-term, sustainable energy source
Disadvantages May be replacing food crops on a finite crop land
and lead to starvation When burnt, it still gives off atmospheric
pollutants, including greenhouse gases. If crops are not replanted,
biomass is a non-renewable resource.
Wood
From Felling or copping trees. Burnt to generate heat and
light
Advantages Cheap Available If the crops are replanted, biogas
can be a long-term, sustainable energy source
Disadvantages Low heat of combustion Not much energy released
for its mass When burnt, it gives off atmospheric pollutants,
including greenhouse gases If trees are not replanted wood is a
non-renewable resource. High cost of transportation as high
volume.
Solar photo volcanic cells
From Conversion of solar radiation into electricity via chemical
energy
Advantages Infinite energy supply Safe Low quality energy
converted to high.
Disadvantages Manufacture and implementation of solar panels can
be costly. Need sunshine, do now work in the dark
Solar-passive
From Using buildings or panels to capture and store heat
Advantages Minimal cost if properly designed.
Wind
From: Can be found singly, but usually many together in wind
farms
Advantages Clean energy and supply once turbines made Little
maintenance required
Disadvantages Need the wind to blow Often windy sites not near
highly populated areas Manufacture and implementation of wind farms
can be costly Noise pollution Some local people object to on-shore
wind farms, arguing that it spoils countryside Question of whether
birds are killed or migration routes disturbed by turbines
Tidal
From: The movement of sea water in and out drives turbines A
tidal barrage is built across estuaries, forcing water through gaps
In future underwater turbines may be possible out at sea and
without dam
Advantages Should be ideal for an isolated country such as the
UK Potential to generate a lot of energy this way Tidal barrage can
double as bridge, and help prevent flooding
Disadvantages Very costly Few estuaries are suitable Opposed by
some environmental groups as having a negative impact on wildlife
May reduce tidal flow and impede flow of sewage out to sea
Wave
From The movement of sea water in and out of cavity on the shore
compresses trapped air, driving a turbine
Advantages Should be ideal for an island country These are more
likely to be small local operations Can be done on a national
scale
Disadvantages Construction can be costly May be opposed by local
or environmental groups. Storms may damage them
Geothermal
From It is possible to use the heat inside the Earth in volcanic
regions. Cold water is pumped into the Earth and comes out as steam
Steam can be used for heating or to power turbines creating
electricity.
Advantages Infinite energy supply Is used successfully in some
countries, such as New Zealand.
Disadvantages Can be expensive to set up Only works in areas of
volcanic activity Geothermal activity might calm down, leaving
power station redundant Dangerous underground gases have to be
disposed carefully
Nuclear fusion energy can be released by the fusion of two
nuclei of light elements
TOPIC 4: Biodiversity and Conservation
Background and Mass Extinctions background extinction rate-
natural extinction rate for species E. O. Wilson- a biologist at
Harvard, thinks that the current rate of extinction is 1000 times
the background rate and is caused by human activities hotspots-
areas where species are more vulnerable to extinction Biologists
thing: we are the sixth mass extinction called theHolocene
extinction eventTo see all 6 mass extinctions refer to the Table on
page 95
The Sixth Mass Extinction far greater than any in the past
already wiped out many large mammal and flightless bird species
humans alter the landscape on an unprecedented scale previous mass
extinctions were due to physical (abiotic) causes over long time
spans current mass extinction is caused by humans (biotic causes)
and is accelerating humans: otransform the environment ooverexploit
other species ointroduce alien species opollute the environment
Worldwide Fund for Nature produces periodic report called the
Living Planet Report omeasures trends in the Earths biological
diversity two phases to the sixth mass extinction o1. when modern
humans spread over the Earth about 100 000 years ago o2. when
humans became farmers 10 000 years agoHotspots some regions have
more biodiversity than others in hotspots there are unusually high
numbers ofendemic species- those only found in that place tend to
be nearer the tropics and are often tropical forests tend to have
large densities of human habituation nearbyKeystone Species species
that have a bigger effect on their environment than others act as
keystone in an arch, holding the arch together their disappearance
can have an impact far greater than and not proportional to their
numbers or biomass ocould destroy the ecosystem or imbalance it
greatly Example: elephants in the African savanna act as engineers,
removing trees, after which grasses can growTypes of Diversity
Biodiversity-the numbers of species of different animals and
plants in different places ocan be considered at three levels:
Genetic diversity-the range of genetic material present in a
species or a population Species diversity-the number of different
species within a given area or habitat Habitat diversity-the number
of different habitats per unit area that a particular ecosystem or
biome contains Simpsons diversity index- measure species diversity
in an area oSimpsons reciprocal index- in which 1 is the lowest
diversity
whereN =the total number of organisms of all species andn =the
total number of organisms of a particular species
How New Species Form Charles Darwin proposed the theory of
evolution which is outlined in The Origin of Species, published in
1859 The theory is summarized bellow oSpeciation-when species are
formed by gradual change over a long time owhen populations of the
same species become separated, they cannot interbreed and may start
to diverge if the environments they inhabit change oseparation may
have geographical or reproductive causes; humans speed up
speciation by artificial selection of plants and animals and by
genetic engineering oover time the population gradually
changes=natural selection othe survival of the fittest
Physical Barriers (examples of species and speciation) oLarge
flightless birds (e.g. emu, ostrich, rhea, cassowary) only found in
Africa, Australia, South America ocichlid fish in the lakes of East
Africa, Lake Victoria, Lake Tanganyika, Lake Malawi oLlamas and
camels (llamas in South America and camels in Africa and central
Asia) Land bridges:allow species to invade new areas Continental
drift:the movement of tectonic plates Plate tectonics:the study of
the movement of plates (continental drift) Plates may either slide
past each other, diverge, or convergeFactors that help to maintain
the biodiversity complexity of the ecosystem stage of succession
(lack of) limiting factors inertiaFactors that lead to loss of
biodiversity
Natural hazards loss of habitat fragmentation of habitat
pollution overexploitation introducing non-native (exotic species)
spread of disease modern agricultural practicesWhat makes a species
prone to extinction?
narrow geographical range small population size of reclining
numbers low population densities and large territories few
populations of the species a large body low reproductive potential
seasonal migrants poor dispersers specialized feeders or niche
requirements hunted for food or sport minimum viable population
size:that is needed for a species to survive in the wild is a
figure that scientists and conservationists considerSpecies
Examples (recovered, extinct, endangered) Recovered Species
oAustralian saltwater crocodile 18 out of 23 were once endangered
listed as protected species in Australia in 1971 overexploited for
skin (leather), meat and body parts through illegal hunting,
poaching and smuggling restored through ranching and closed-cycle
farming oGolden lion tamarin (GLT) recovered or not? small monkey
endemic to Atlantic coastal rainforests of Brazil omnivores only 2%
of their native habitat is left poachers earn US$20 000 for skin
captive breeding program some re-introduced to the wild but with
only 30% of success their future uncertain Extinct Species
oThylacine (Tasmanian tiger) life expectancy of 12-14 years
habitat: open forests and grassland competed with dingoes on the
mainland of Australia hunted by farmers whose stock of sheep was
the species prey hunting, poisoning, and trapping shooting parties
organized for tourists entertainment last one has been killed in
1930 now introduced dogs have taken over the ecological role of the
thylacine oDodo large flightless bird endemic to the island of
Mauritius ground-nesting bird 1505 Portuguese sailors ate dodo as a
source of fresh meat new species introduced that ate dodo humans
killed the birds for sport destruction of habitat extinct by 1681
fauna impoverished by its loss became an icon due to its apparent
stupidity Endangered species oRafflesia tropical parasitic plant in
the forests of South-East Asia single sexed pollination must be
carried out when the plant in bloom vulnerable because they need
specific conditions to survive deforestation and logging destroy
their habitat now there are Rafflesia sanctuaries
TOPIC 5: Pollution Management
Pollution: the addition of substances to the biosphere by human
activity, at a rate greater than could be rendered harmless by the
env-t
-Major sources of pollution (table on p. 277) Combustion of
fossil fuels Domestic waste Industrial waste Agricultural waste
-Point source pollution the release of pollutants from a single,
clearly identifiable site(e.g factory chimney, waste disposal pipe)
easier to locate easier to manage
-Non-point source pollution: the release of pollutants from
numerous, widely dispersed origins (e.g. vehicles, chemical spreads
on fields) Difficult to locate General restrictions could be put to
control it
Detection and monitoring of pollution
Indicator species: species that are only found if the conditions
are either polluted or unpolluted
-Biochemical oxygen demand (BOD) The measure of the amount of
dissolved oxygen required to break down the organic material in a
given volume of water through aerobic biological activity Indirect
pollution measurement Higher BOD more pollution
-Biotic index A 1 to 10 scale Gives a measure of the quality of
an ecosystem by the presence and abundance of the species living in
it Indirect method Used at the same time as BOD measurements
-Three-level model of pollution management a model for reducing
the impact of pollutants replace, regulate, restore model Refer to
figure 15.3 on page 282 Pollution management strategies (refer to
case study on p282-283)
-Domestic Waste (Solid domestic waste or municipal solid waste)
Makes up about 5% of total waste 3kg of solid waste per capita in
USA solid waste production has risen from 300kg per year in 1985 to
500
Strategies to minimize waste
-Recycling Collecting and separating waste materials and
processing them for reuse E.g. aluminum canso Only 5% of energy
needed to recycle ito Can be recycled indefinitely
-Disposal of waste: Landfill Waste buried in a suitable site
Lined with special plastic liner to prevent leachate (liquid waste)
from seeping out Produced methane could be used to generate
electricity
-Disposal of waste: Incinerators Burning of waste at high
temperatures Heat produced is used (heat-to-energy incineration)
Smaller land area used than in landfill Ash from incinerators could
be used in road building Expensive
-Disposal of waste: organic waste Could be composted or put into
anaerobic digesters Produced methane could be used as fuel
Eutrophication
The addition of excess nutrients to a freshwater ecosystem Could
be a natural process Usually nitrates and phosphates from:
detergents, fertilizers, sewage etc.
-The process of eutrophication Fertilizers wash into a river or
lake High levels of phosphate allow faster algae growth Algal
blooms block the sunlight More algae more food for zooplanktonmore
food for fishless zooplankton Algae die and are decomposed Not
enough oxygen in waterfood chains collapseorganisms die Dead
organic material forms sediments on the river bed and turbidity
increases A clear blue lake is leftReduces biodiversity in
slow-moving water bodies, temporary reduction in biodiversity in
fast-moving waters
-Eutrophication management strategies (refer to table 15.4 on p.
287)
-Impacts of eutrophication Bad smell Rivers/lakes covered by
green algal scum and duckweed Anaerobic water (oxygen-deficient)
Loss of biodiversity and shortened food chains Death of higher
plants Death of aerobic organisms invertebrates, fish and
amphibians Increased turbidity
Introduction to ozone
Found in stratosphere, where it blocks UV radiation, and
troposphere
-Depletion of stratospheric ozoneThe ozone layero Reactive gas
mostly found between 20 and 40km altitudeo Made from oxygen (O2)o
UV radiation is absorbed in its formation and destructiono The
ozone layer absorbs more than 99% of UVC radiationDamaging effects
of UV radiationo Mutationo Damage to photosynthetic organismso
Damage to consumers of photosynthetic organisms
-The action of ozone depleting substances Liming lakes: adding
powdered limestone raises the pH but the effects are short-lived
Reducing emissions: reducing combustion of fossil fuelso
Precombustion: removing sulfur from the fuel before combustiono end
of pipe measures
TOPIC 6: The Issue of Global Warming
The greenhouse effect is a normal process which is necessary for
the maintenance of the Earths surface temperature. The effect is
caused by gases in the atmosphere reducing heat losses by radiation
back into space. They trap heat energy that is reflected from the
Earths surface, and reradiate some back into space some back to
Earth. Greenhouse gases absorb infrared radiation radiated from the
Earths surface and pass this heat to other atmospheric gases.
Incoming solar radiation is made up of visible light, ultraviolet
light, and infrared heat. About 45% of incoming light is absorbed,
scattered or reflected by the atmosphere and clouds before it
reaches the Earths surface. Of the 55% that reaches the surface 4%
is reflected and 51% is absorbed, which is used for photosynthesis,
heating the ground and seas, and evaporation. It is then released
back into the environment as longer wavelength infrared energy
(heat energy). Therefore if we had no greenhouse gases this energy
would be lost to space.
As humans increase emissions of some greenhouse gases, the
greenhouse effect is enhanced. Most scientists believe that this is
what is causing global warming and climate change. See Pg 136 Fig.
7.1 and 7.2. Human activities (anthropogenic activities) are
increasing the amounts of greenhouse gases in the atmosphere.
Greenhouse gases (GHGs) include not only carbon dioxide but also
water vapour, methane, and chlorofluorocarbons (CFC). CFCs are
chemicals made by humans which destroy the ozone layer when they
reach the stratosphere, but acts as GHGs in the troposphere. Water
vapour has the largest effect in trapping heat energy (about 36-66%
of greenhouse effect). Most GHGs are there through natural
processes but it is the increase, which is caused by anthropogenic
activities which is of concern.
CFCs have a very high global warming potential (GWP) higher than
carbon dioxide, which means it contributes the most per molecule to
the greenhouse effect and therefore global warming. Methane is also
increasing by about 1% per year due to human activities (about 60%
comes from human and 15% from cattle). Methane can be used as a
source of energy and many developed countries capture and pipe
methane to be used to generate electricity of for heat. Carbon
circulates through the atmosphere and is found in four main
storages: the soil; living things (biomass); the oceans; and the
atmosphere. Carbon sinks are stores of carbon found in soil,
biomass, and oceans. The biggest contributor of carbon to the
atmosphere is through the burning of fossil fuels. The amount of
carbon on the planet is finite and is called the carbon budget.
Human activity has disrupted the balance of the global carbon
cycle, through increased combustion, land use changes, and
deforestation.
Changes in the climate can be seen in a variety of ways: changed
temperatures and or rainfall patterns, more severe storms, ice
sheet thinning or thickening, and sea level rises.
There are five ways that the climate can change overtime due to
conditions on Earth and GHG levels changing: the more damage we do
the more change will occur; there may be a buffering action in
which climate change does not follow in a linear way (it is
resistant to change); climate change may respond slowly at first
but then accelerate until it reaches a new equilibrium; climate may
not respond but then tip over the threshold and change rapidly
until a new, much higher equilibrium is reached; in addition to the
threshold change it may get struck at the new equilibrium even if
factors causing the change cease to exist.
Effects on oceans and sea levels: Sea levels are rising due to
increased temperatures causing water to expand and ice to melt
which then runs off into the seas. The Greenland and Antartic ice
sheets are thinning, and, this and the thermal expansion of the
seas will mean that sea levels will rise even more. An increase of
between 1.5 and 4.5C could mean a sea level rise of 15-95cm (IPCC
data). If there is a threshold and this is exceeded then sea levels
could rise by metres. This could be disastrous for low-lying
countries like the Maldives, Kiribati, Tuvalu, and the Netherlands.
The oceans absorb carbon dioxide and this makes them slightly
acidic. They have become more acidic by 0,1 pH as they have
absorbed about half the carbon produced by anthropogenic
activities. This will obviously affect marine life. As they warm
they absorb less carbon dioxide which is a problem. Effects on
polar ice caps: Melting of land ice on Antarctica and Greenland
will cause sea levels to rise as it flows into the sea. Glaciers
are melting causing increased volumes of water. The Greenland ice
sheet could melt completely and slow down or even stop the North
Atlantic Drift (NAD) current by diluting the salt water. If the NAD
current and the Gulf Stream slow or even shut down, the climate of
the UK and Scandinavia would be much colderThe melting of the Artic
could open up trade routes and allow for exploitation of undersea
minerals and fossil fuel reserves. Methane clathrate is a form of
ice under the Artic ocean floor that traps methane. If it were to
melt and reach the surface, the release of methane might trigger a
rapid increase in temperatures. Effects on food production: Warmer
temperature should increase the rate of biochemical reactions so
photosynthesis should increase. But respiration will also increase
therefore there may be no increase in NPP. In Europe the crop
growing season has expanded. If biomes shift away from the equator,
there will be winners and losers. It depends on the fertility of
soils as well. For example if production shifts northwards from the
Ukraine with its rich black soils to Siberia with its thinner, less
fertile soils, NPP will decrease. In seas, a small increase in
temperature can kill plankton, the basis of many marine food webs.
Effects on biodiversity and ecosystems: Melting of tundra
permafrost would also release methane which is trapped in the
frozen soils. Animals can move to cooler regions plants can not.
The distribution of plants can shift as they disperse seeds which
germinate and grow in more favourable habitats. But this happens
very slowly and could be too slow to stop them from becoming
extinct. Species in alpine or tundra regions have no where to go,
neither up nor towards higher latitudes. Polar species could become
extinct in the wild. Birds and butterflies have already shifted
their ranges to higher latitudes. Plants are breaking their winter
dormancy earlier. Loss of glaciers decrease the salinity of marine
waters and changes to ocean currents alter habitats. If droughts
increase wildfires are more likely to wipe out other species. An
increase in temperatures of fresh and salt water may kill sensitive
species, and national parks and reserves could find their animals
dying. Pine forests in British Columbia (Canada), are being
devastated by pine beetle, which is not being killed off by
previously cold winters which have become milder. Effects on human
health: malaria, yellow fever, and dengue fever could spread to
higher latitudes. In a wetter climate fungal diseases will
increase. In a drier climate dust increases leading to asthma and
chest infections. Warmer temperatures in higher latitudes would
reduce the number of people dying from the cold each year and
reduce heating bills for households.Effects on human migration: If
people can not grow food or find water, they will move to regions
where they can. Global migration of millions of environmental
refugees is quite possible and this would have implications for
nation states, services and economic and security policies. The
IPCC estimates that a 150 million refugees from climate change in
2050. Effects on national economies: Some economies would suffer if
water supplies decrease or drought occurs. This could open up new
resources such as tar sands in Canada and Siberia, which have been
frozen under permafrost. If rivers dont freeze hydroelectric power
generation will be possible at higher latitudes. Agricultural
production may increase in higher latitudes but fall in the
tropics.
Carbon dioxide is responsible for two-thirds of anthropogenic
greenhouse effect. China is probably the most prolific emitter
having overtaken the U.S.A. According to the Earth Policy
Institute, carbon emissions from fossil fuel burning was 8.38 Gt
(109 tonnes)of carbon in 2006, 20% above the 2000 level and running
at an increase per year of about 3.1 %. Strategies to alleviate
climate changeThere are three strategies that we can adopt on this
issue: do nothing; wait and see; or take precautions now. Science
can not give us 100% certainty on the issue of global warming nor
predict with total accuracy what will happen. What it can do is
collect data and provide evidence. How that evidence is interpreted
and extrapolated will depend on individual viewpoints, scientific
consensus, economics and politics. Sceptics of the validity of
global warming and climate change and, its human cause, may adopt a
do nothing approach due to there consideration of it as a
non-threat. In addition to this they say that global warming is a
good thing and technology can manage its effects.
The wait and see approach is risky as it is a long slow process
to move the global economy away from fossil fuel usage. It could be
an unnecessary disruption of national economies. It is possible
however that we will reach the tipping point when our actions will
have little effect as positive feedback mechanisms change the
climate to a new equilibrium, which could be 8 degrees warmer than
it is now.
The precautionary strategy is the majority choice, which focuses
on acting now in case. Even if we found out that fossil fuel
burning is not the cause of global warming we know that these fuels
will run out and it makes sense to clean up the Earth and find
alternative fuel sources now before we run out. What we are seeing
in current national policies and international targets, are
precautions (carbon emission reduction, carbon-offset, lifestyle
changes) against increased climate change. These precautions can be
divided into three categories: international commitments (Kyoto);
national actions; and personal lifestyle changes.
Kyoto Protocol1997: signed by some 160 nations at the third
United Nation Framework Convention on Climate Change conference
(UNFCCC).The protocol calls for the first ever legally binding
commitments to reduce carbon dioxide and 5 other greenhouse gas
emissions to 2.2 % below 1990 levels before 2012. The US signed but
has not ratified the protocol. 2004: The Kyoto Protocol is still
ineffective. For the protocol to be effective at least 55 countries
have to ratify (fully adopt the commitments) and there must be
enough developed countries who together are accountable for more
than 55% of emissions according to 1990 levels. However the
percentage of developed countries is only 37.5%. 2005: Kyoto
Protocol goes into effect. Signed by major industrial nations
except US. Worked to slow emissions accelerates in Japan, Western
Europe, US regional governments and corporations.
TOPIC 7: Environmental Value Systems
Environmental philosophieso Ecocentric: life-centered, respects
rights of the nature and the dependence of humans on natureo
Technocentric/Anthropocentric: human-centered, humans are not
dependent on nature, but nature is there to benefit the human
kind
Technocentric worldviewso Cornucopians: people who see the world
having infinite resources to benefit humanity. Believe that the
env-tal problems could be solved with technologies, improving our
living standardso Env-tal managers(stewardship): believe that we
have an ethical duty to protect the nature. Support limited
limiting resource exploitation. Believe that if we look after the
planet, it looks after us
Nurturing vs. intervening or manipulative approaches=
environmental vs. technocentric worldviewsEcocentric worldviewso
Biocentric: all life has an inherent value, not just for humans.
Some philosophies believe that humans arent any more important than
other species.o Soft technologists: believe in small-scale local
community action and emphasize the role of individuals making a
differenceo Deep ecologies: put more value on nature than humanity.
Believe in biorights universal rights of all species and
ecosystems; advocate strong policy and population change
Various environmental worldviewso Communism and capitalism in
Germany- disregarding value of the environment and exploiting
resourceso Native American- Use low impact technologies and respect
nature- Polytheistic religion believes that animals and plants have
a spiritualityo Modern Western- view earth as a resource for
humanity.- Ecofeminists argue that it is the rise of male-dominated
species that has led to our view of nature as a foeo Buddhisms
view- believe that we are all dependent on each other and preaches
that all being are equal- believe that all living organisms share
the conditions of birth, old age, suffering and death
