Chapter 1 The Environment and Sustainability
1.1 What are some key concepts of sustainability
1.1A Life one earth has been sustained for billions of years by solar energy, biodiversity and
chemical cycling
1.1B Our lives and economies depend on energy from the sun and on natural resources and
ecosystem services provided by the earth
1.1C We could live more sustainably by following six principles of sustainability
Environment: Everything around you (living and unliving)
Environmental Science: A study of connections nature. Study of (1) how the earth works and
has survived and thrived, (2) how humans interact with the environment, (3) how we can live
more sustainably
Ecology: focuses on living organisms and how they interact with their environment
Species: group of organisms having a unique set of characteristics
Ecosystem: a set of organisms within a defined area
Environmentalism: Social movement to protect the earth
Three scientific principles of sustainability (lessons from nature)
• Dependence on solar energy: gives plants energy to survive
• Biodiversity: variety of genes, species, ecosystems and ecosystem processes. Keeps
population from growing to large, provides ways for species to adapt to environmental
changes and replaces species wiped out
• Chemical cycling: circulation of chemicals or nutrients needed to sustain life from the
environment through various organisms and back to the environment. Waste becomes
a useful resource through the process.
Types of resources:
Inexhaustible resource: expected to last for at least a billion years (sun)
Renewable source: can be replenished. Highest rate at which people can use this indefinitely
without reducing its available supply is its sustainable yield
Non-renewable: exist in fixed amount, we can use them faster than nature can replace them
Ecosystem services: natural services provided by healthy ecosystems that support life and
human economies at no monetary cost to us (e.g. forests help purify air and water)
Our lives and economies are sustained by energy from the sun and by natural resources and
ecosystem services
Human activities can degrade natural capital by using renewable sources faster than nature
can restore them and by overloading the earth’s normally renewable air, water and soil with
pollution and wastes.
Additional principles of sustainability
• Full-cost pricing: including environmental and health costs in market pricing à gives
consumers info about the effects
• Win-win solutions: based on cooperation and compromise to benefit the largest number of
people as well as the environment
• Responsibility to future generations: we should leave the planet’s life-support systems in a
condition that is as good as or better than it is now
For these principles we should use biomimicry as a major tool for learning how to live more
sustainably.
More developed countries (industrialized nations) with 17% of the world’s population use about
70% of the earth’s natural resources (US about 30%), while less developed countries with 83%
of population uses only 30% of the world’s natural resources
,1.2 How are our ecological footprints affecting the earth?
1.2A Humans dominate the earth with the power to sustain, add to, or degrade the natural
capital that supports all life and human economies
1.2 As our ecological footprints grow, we deplete and degrade more of the earth’s natural
capital that sustains us
Environmental degradation: we waste deplete and degrade much of the earth’s life sustaining
natural capital.
Human activities directly affect 83% of the earth’s land surface (excluding Antarctica). This
land is used for urban development, food production etc.. Human activities have overused
about 60% of the ecosystem services provided by nature, mostly since 1950. There are
scientific, economic and political solutions to these problems that could be implemented within
a few decades.
Some renewable resources are not always owned by anyone and can be used by almost
anyone (e.g. atmosphere, ocean). Others can be less open but shared resources (e.g.
grasslands, forests, streams and aquifers). Many of these resources have been degraded →
Tragedy of the commons (Garrett Hardin)
One way to deal with this difficult problem is using these resources at a rate well below its
estimated sustainable yield> This can be done by mutually agreeing to use less of the
resource, regulating access or both.
Other way: convert shared resources to private ownership (not really possible)
Ecological footprint: harmful environmental impact- the amount of biologically productive land
and water needed to supply a population in an area with renewable resources and to absorb
and recycle the wastes and pollution such resource use produces.
Biocapacity: The ability of its productive ecosystems to regenerate renewable resources used
by a population and to absorb the resulting wastes and pollution indefinitely.
If the ecological footprint > the biocapacity a country has an ecological deficit
We need 1.5 planet earths to sustain the world’s 2012 rate
Everything in nature is connected → everything we do to it, we do to ourselves
Environmental impact model IPAT:
IPAT shows that the environmental impact (I) of human activities is the product of three factors:
population size (P), affluence (A) or resource consumption per person, and the beneficial and
harmful effects of the technologies (T).
I=PXAXT
T can be harmful or beneficial
Since prehistoric hunter-gatherers ages three major cultural changes
1. Agricultural revolution: humans learnt how to grow and breed plants and animals for
food clothing and other purposes
2. Industrial-medical revolution: people invented machines for large-scale production of
food and goods. People moved from villages to cities. Learnt to get energy from fossil
fuels and how to grow large quantities of food efficiently. Medical advances such as
living longer and healthier
3. Information-globalization revolution: developed new technologies for gaining rapid
access to all kinds of information and resources on a global scale.
All cultural changes contributed to population growth, greater resource use which expanded
our ecological footprint
Some technologies have also led us to decrease this (e.g. LED lights). This could lead to a
fourth revolution: The Sustainable revolution
, 1.3 What causes environmental problems and why do they persist?
1.3A Basic causes of environmental problems are population growth, wasteful and
unsustainable resource use, poverty, avoidance of full-cost pricing, increasing isolation from
nature, and different environmental worldviews
1.3B Our environmental worldviews play a key role in determining whether we live
unsustainably or more sustainably
Exponential growth: quantity increases at a fixed percentage per unit of time
Human population has grown exponentially leading to greater resource use to sustain life for
more people on earth.
Higher incomes leads to higher affluence. Affluence can also lead to widespread and better
education about environment and makes more money available for developing technologies
to reduce pollution, environmental degradation and resource waste
Poverty: lack money to fulfil basic needs for food, water, shelter, health care and education
People in poverty are desperate for short-term survival, don’t take long term environmental
effects into account (degrading forests, topsoil and grasslands)
Some also plant and nurture trees and conserve the soil they depend on.
Environmental degradation can have health effects on the poor: malnutrition, illness due to
limited access to sanitation facilities and clean water. Result is that they get water from
environmentally bad sources.
Avoidance of full-cost pricing. Main objective is to maximise profits, so there is no incentive to
take environmental effects into account
Another issue are subsidies form the government to assist with using non-renewable resources
to run their businesses. Creates jobs but depletes environment.
Solutions: switching from unsustainable to sustainable subsidies, increase taxes on pollution
and reduce taxes on income and wealth we want more off.
Isolation from nature from nature. Most people live in cities, use electronic devices which
isolate people from the natural world. Research shows that experiencing nature improves
health, reduces stress, improves mental abilities and increases imagination and creativity. It
can also provide wonder and connection to the earth’s life-support.
Different views. Environmental ethics: study of varying beliefs about what’s right or wrong with
how we treat the environment. We have different beliefs is because we start with different
assumptions and moral, ethical or religious beliefs.
Three categories: 1. human-centred, 2. life-centred and 3. earth-centred
1. Natural world is the support system for human life. Planetary management worldview
and stewardship worldview. Both humans are separated from and in control of nature.
2. All species have value in fulfilling their particular role within the biosphere
3. We are part of and dependent on nature and its capital exists for all species
1.4 What is an environmentally sustainable society?
1.4A Living sustainably means living on the earth’s natural income without depleting or
degrading the natural capital that supplies it.
Protect your capital and live on the income it provides.
Living sustainably is living on natural income → renewable resources such as plants, animals,
soil, clean air and clean water provided by the earth’s natural capital.
Living sustainably is learning to live within limits. Doing this requires:
- Learning form nature
- Protecting natural capital
, - Not wasting resources
- Recycling and reusing non-renewable resources
- Using renewable resources no faster than nature can replenish them
- Incorporating harmful health and environmental impacts of producing and using goods and
services in their market prices
- Preventing future ecological damage and repairing past damage
- Cooperating with one another to fine win-win solutions to the environmental problems we face
- Accepting ethical responsibility to pass earth that sustains us on to future generations in a
condition as good or better than what we inherited
Chapter 2: Science, Matter, Energy and Systems
2.1 What do scientists do?
2.1.1 Scientists collect data and develop hypotheses, theories and laws about how nature
works.
Cause-and-effect patterns can be understood through observations, measurements and
experimentation. Scientists collect data to answer your question. From the data collected they
propose a scientific hypothesis.
Another way is to develop a model: approximate physical or mathematical simulation of a
system.
Scientific theory is a well-tested and widely accepted scientific hypothesis or a group of related
hypotheses. One of the most important results of science.
Scientists must be curious and sceptical. One important feedback is a peer review.
1. Think critically about everything u read or hear
2. Evaluate evidence and hypotheses using inputs and opinions from a variety of reliable
sources
3. Identify and evaluate your personal assumptions, biases and beliefs and distinguish
between facts and opinions before coming to a conclusion
Scientific law or law of nature: well-tested and widely accepted description of what we find
always happening in nature
Tentative science: preliminary scientific results without adequate testing and peer review
Limitations of science
- Science can never prove anything absolutely, there’s always some degree of uncertainty in
measurements, observations, models and the resulting hypotheses and theories → high
probability or certainty is the objective (90-95%)
- Scientists are human and not always free of bias, reduced personal bias due to peer reviews
- Many systems in the world involve a huge number of variables. Mathematical models are
used to deal with this
- Use of statistical tools
2.2 what is matter and what happens when it undergoes change?
2.2a matter consists of elements and compounds, which in turn are made up of atoms, ions or
molecules
2.2b whenever matter undergoes a physical or chemical change, no atoms are created or
destroyed (law of conservation matter)
Matter: anything that has mass and takes up space. Can be solid, liquid or gas (physical states)
and elements and compounds (chemical forms)
Element: (e.g. gold or mercury) has a unique set of properties and cannot be broken down into
simpler substances by chemical means.
Compounds: combinations of two or more elements held together in fixed proportions (H20)
