Ch. 1 Environmental Problems, Their Causes, and Sustainability
Exponential Growth
The increase in growth of some” quantity” such as the human population
that increases at a constant rate per unit of time.
When plotted over time growth yields a “J” curve.
Between 1950 and 2004, the world’s population increased exponentially from
2.5 billion to 6.4 billion and is expected to increase somewhere between 8-12
billion by the end of this century.
Exponential Growth plays a key role in 5 interconnecting environmental
issues:
- population growth
- resource use and waste
- poverty
- loss of biodiversity
- global climate change
1.1Living More Sustainably
Environmental Science is interdisciplinary
-physical sciences
-biological sciences
-social sciences
Environmentalists study how the earth works, our interactions with the
earth and the methods/procedures used to deal with environmental
problems.
Environmentalism –
Solar Capital – Natural Capital
All life is dependent upon solar capital (solar energy) and natural capital
(Earth’s resources and ecological services)
“Capital” is wealth
Solar Capital:
- direct – sunlight (solar energy)
- indirect – renewable solar energy - wind power, hydropower
biomass – solar energy converted to organic compds. by autotrophs
Natural Capital:
- resources – air, water, soil, energy resources, minerals
- ecological services –pollution control, nutrient recycling, climate
control, pollution control, waste treatment, biodiversity, pest and disease control
The natural capital that nature provides is at no cost to us and can sustain the planet indefinitely as long as we do not deplete them.
What’s the underlying problem??
Man must protect our solar and natural capital and live off the resources they provide by eliminating waste and discontinuing the depletion and degradation of resources – we must become an environmentally sustainable society.
Living sustainably means protecting your capital and living off the income it provides.
1.2Population Growth
Economic Growth – an increase in the capacity of a country to provide people
with goods and services.
What is needed for growth? :- an increase in the population
- more production and consumption
per person
- or both
How is it measured? % change in a country’s Gross Domestic Product
GDP – the annual market value of all goods and services produced by
all firms and organizations operating within the country
Standard of living for a country is measured by per capita GDP (GPD/total population)
Economic development – the improvement of living standards by brought
about by economic growth
The classification of a nation is based on per capita GDP (degree of industrialization):
- Developed Countries ( 1.2 billion people)
US, Canada, Japan, Australia, New Zealand, Countries of Europe
- longer life expectancy – decreased infant mortality
- greater food production than food needs
- decreased pollution
- decreased poverty
2. Developing Countries (5.2 billion people)
Africa, Asia, Latin America
- poverty produces harmful environmental effects
- soil, water, and forest are depleted
- pollution levels are high
- infant mortality rate is 8X higher
- poor working conditions, very low wages
97% of projected increase in world population is expected to
take place in these countries
Globalization – world interconnectedness
Increasing exchanges of people, products, services, capital,
and ideas across international borders.
A sustainable community or country must recognize that we are a part of a larger global economy and ecological system that cannot be sustainable unless these larger systems are also sustainable.
1.3 Resources
Resource:
3 types:
- Perpetual –
- Renewable –
Works as long as the resource is not used up faster than it is
replaced.
Ex: Fresh air
Fresh water
Fertile soil
Plants and Animals
Sustainable yield:
Environmental degradation:
Ex: urbanization of productive land
Excessive topsoil erosionover grazing
Pollutionreduced biodiversity
Deforestationhabitat destruction
Ground water depletion
Tragedy of the Commons
Garrett Hardin, biologist in 1988, described the degradation
of freely available resources – no one owns these free access
resources
the cumulative effect of many people trying to exploit a free-
access resource eventually exhausts or ruins it.
Produces problems like ocean pollution, abuse of national parks,
air pollution, etc.
Possible solutions:
Limit access to resources, converting to private ownership
Ecological Footprint
The amount of biologically productive land and water needed
to supply each person or population with the renewable
resources they use and to absorb or dispose of wastes for
such resources used.
The average footprint per person is 15-20% higher than can
be sustained indefinitely. At the current rate, we
would need 4 planet Earths to sustain the consumption levels in
the U.S. This results in the environmental problems we face.
- Nonrenewable Resources
Include: fossil fuels (oil, natural gas, coal)
Metallic mineral resources (iron, copper, aluminum, etc.)
Nonmetallic mineral resources (clay, sand, phosphates, etc.)
Solutions:
Find more of the source
Recycle the resource, reuse the resource
Waste less
Use less
Develop a substitute for the resource
wait million of years for more to be produced
1.4 Pollution
Pollution:
Most pollutants are unintended by-products of useful activities such as burning coal to generate electricity, driving cars and growing crops.
2 types:
1. Point Sources:
Easier to control this type of pollution
Ex. smoke stacks, drainage pipe of factory, automobile exhaust,
- NonpointSources:
Ex. pesticides sprayed into air and blown by wind, runoff of
Fertilizers and pesticides from farmland and golf courses enter streams away from the source – hard to identify source
Unwanted effects: Degrade life support systems of any organism
Damage human health, wildlife and property
Produce nuisances in noise, smells, tastes, and sights
1.5 Environmental and Resource Problems: Causes and Connections
6 major causes of environmental problems:
1. Population growth
2. Wasteful resource use
3. Poverty
4. Bad environmental accounting
5. Ecological ignorance
6. Inadequate understanding of how the earth works
Affluenza:
Affluenza of developed countries can lead to environmental improvements
More money for technology
Compared to 1970, air and water are cleaner because $ was spent
Environmental quality is affected by interactions between population size, resource consumption, and technology. 3 Factor Model
1.6Is Our Present Course Sustainable?
Good and Bad news – strides have been made but there is much more to do
If degradation of the environment is not halted, sustainable development is not possible. Technological optimists say don’t worry
Environmental pessimists see the problem as hopeless
Present and future environmental problems:
- Poverty and malnutrition
- smoking and air pollution
- Aids
- Climate change and water shortages
- Decline in biodiversity
- Earth’s natural capital will be degraded so that we are at greater risks
To live more sustainably:
- identify how the earth has sustained itself
- apply this information to our lifestyles and economies
- use economic rewards to encourage more sustainable forms of economic growth
- use economic penalties to discourage unsustainable forms of economic growth
Change comes from dedicated, committed people – 5-10% of a population can bring
about major social change.
Guidelines for working with the earth:
- Never leave the earth worse than you found it.
- Take only what you need.
- Do no harm.
- Sustain diverse living organisms.
- Maintain earth’s capacity for self-repair and adaptation.
- Do not waste; do not pollute.
- Decrease population; reduce poverty.