1. ENS501 Introduction to Environment
Week 1

2. Environment The environment is everything around us.
“Environment is everything that isn’t me” – Albert Einstein
Environment includes all living and nonliving things (air, water, and energy) with which an organism interacts.
We are dependent on the environment for clean air and water, food, shelter, energy, and everything else we need to stay alive and healthy.

3. Environmental Science
Environmental science is an interdisciplinary study of how humans interact with living and nonliving parts of their environment.
It integrates information and ideas from natural sciences, social sciences and humanities.
The three goals of environmental science:
To learn how life on the earth has survived and thrived
To understand how we interact with the environment
To find ways to deal with environment problems and live more sustainably.

4. Ecology Ecology – a key component of environmental science
Ecology is the biological science that studies how organisms, or living things, interact with one another and with their environment.
Every organism is a member of certain species: a group of organisms that have distinctive traits (or characteristics) and, for sexually reproducing organisms, can mate and produce fertile offspring.

5. Ecosystem
An ecosystem is a set of organisms within a defined area or volume interacting with one another and with their environment of nonliving matter and energy.
For example, a forest ecosystem consists of plants (especially trees), animals, and mostly tiny micro-organisms that decompose organic materials and recycle their chemicals, all interacting with one another and with solar energy and the chemicals in the forest’s air, water, and soil.

6. Environmentalism
Environmentalism is a social movement dedicated to protecting the earth’s life-support systems for all forms of life.
Environmentalism is practiced more in the political and ethical arenas than in the realm of science.

7. Sustainability
Sustainability is the ability of the earth’s various natural systems and human cultural systems and economies to survive and adapt to changing environmental conditions indefinitely.
Nature has sustained itself for billions of years. The three over-arching science-based themes to the long-term sustainability of life on this planet: energy, biodiversity, & nutrient cycling.

8. Three Principles of Sustainability

9. 3 Principles of Sustainability (or Lessons from Nature)
Three principles of sustainability are solar energy, biodiversity, and nutrient cycling.
Solar energy warms the earth and provides energy for plants to produce nutrients, or the chemicals necessary for life. All life on earth depends upon solar energy.
Biodiversity (biological diversity) is the variety of organisms, the natural systems in which they live and the natural services that they provide.

10. 3 Principles of Sustainability (or Lessons from Nature)
Nutrient cycling is the circulation of nutrients, or chemicals from the environment (mostly from soil and water) through organisms and back to the environment is necessary for life.
Natural processes keep this cycle going.
This means there little waste in nature because the wastes of organisms become nutrient raw materials for other organisms.

11. Sustainability - key components
Natural capital—the natural resources and natural services that keep us and other forms of life alive and support our economies.
Our lives and economies depend on energy from the sun (solar capital) and natural resources & natural services (natural capital) provided by the earth.
Natural capital = Natural Resources + Natural Services

12. Natural Resources & Services
Natural resources are materials and energy in nature that are essential or useful to humans.
These resources are often classified as renewable (such as air, water, soil, plants, and wind) or nonrenewable (such as copper, oil, and coal).
Natural services are processes in nature such as purification of air and water, which support life and human economies.

13. Natural Capital = Natural Resources + Natural Services
Solar energy
Natural Capital = Natural Resources + Natural Services
Air
Renewable energy (sun, wind, water flows)
Air purification
Climate control
UV protection
(ozone layer)
Life
(biodiversity)
Water
Population control
Water purification
Pest control
Waste treatment
Figure 1.3: These key natural resources (blue) and natural services (orange) support and sustain the earth’s life and human economies (Concept 1-1a).
Nonrenewable minerals
(iron, sand)
Soil
Land
Soil renewal
Food production
Natural gas
Nutrient recycling
Oil
Nonrenewable energy
(fossil fuels)
Coal seam
Natural resources
Natural services
Fig. 1-3, p. 9

14. Natural Service (Nutrient cycling)
One vital natural service is nutrient cycling.
An important component of nutrient cycling is topsoil – a vital natural resource that provides food.
Without nutrient cycling in topsoil, life could not exist on the earth’s land.

15. Nutrient cycling

16. Natural Capital Degradation
Many human activities can degrade natural capital by using normally renewable resources faster than nature can restore them, and by overloading natural systems with pollution and wastes.
Natural capital degradation occurs when the natural resources and services are hurt.
Solutions are being found and implemented.

17. Natural Capital Degradation
Solutions to natural degradation, such as
reducing energy consumption
reducing resource use and
advocating a reduction in population growth,
may require economic changes and life-style modifications.
Sustainability begins at personal and local levels.

18. Resources Humans depend on resources to meet our needs.
A resource is anything obtained from the environment to meet our needs and wants.
Solar energy, fresh air, fertile topsoil, wild edible plants are directly available for use.
Other resources such as petroleum, iron, underground water, and cultivated crops become useful to us only with some effort and technological ingenuity.

19. Resource Types
A perpetual resource is continuously renewed and expected to last (e.g. solar energy).
Solar energy is called a perpetual resource because it is renewed continuously and is expected to last at least 6 billion years as the sun completes its life cycle.

20. Renewable Resource
A renewable resource is replenished in days to several hundred years through natural processes as long as it is not used up faster than it is renewed.
Examples include forests, grasslands, fish populations, freshwater, fresh air, and fertile soil.
Sustainable yield of a renewable resource is the highest rate at which it can be used indefinitely without reducing its available supply.

21. Nonrenewable Resource
Nonrenewable resources, such as coal and oil, exist in a fixed quantity, or stock, in the earth’s crust and take millions to billions of years to renew.
We can deplete these resources much faster than nature can form them.
Exhaustible energy (coal and oil).
Metallic minerals (copper and aluminum).
Nonmetallic minerals (salt and sand).

22. Sustainable Solutions
Sustainable solutions: Reduce, reuse, recycle.
Recycling involves collecting waste materials and processing them into new materials, for example cans that are collected and reprocessed.
Reuse means using a resource over and over in the same form, for example glass bottles that are collected, washed, and refilled many times.

23. Sustainable Solutions
Recycling nonrenewable metallic resources uses much less energy, water, and other resources and produces much less pollution and environmental degradation than exploiting virgin metallic resources.
Reusing such resources has a lower environmental impact than recycling.
From an environmental and sustainability viewpoint: Reduce, reuse, recycle.

24. Rich and poor countries have different environmental impacts
The United Nations classifies the world’s countries as economically more developed or less developed based primarily on their average income per person.
High-income countries include the United States, Canada, Japan, Australia, New Zealand, and most countries of Europe.
Middle-income countries include China, India, Brazil, Thailand, and Mexico.
Low-income countries include Congo, Haiti, Nigeria, and Nicaragua.

25. ecological footprints

26. Environmental Degradation
Also known as natural capital degradation
It is occurring at an accelerating rate.
Environmental degradation is when the use of a renewable resource exceeds its natural replacement rate, causing the available supply to shrink.
Examples include climate change, soil erosion, aquifer depletion, decreased wildlife habitats, species extinction, and declining ocean fisheries.

27. Natural Capital Degradation
Degradation of Normally Renewable Natural Resources
Climate change
Shrinking
forests
Decreased wildlife
habitats
Air pollution
Species extinction
Soil erosion
Water pollution
Declining ocean fisheries
Aquifer depletion
Figure 1.5: These are examples of the degradation of normally renewable natural resources and services in parts of the world, mostly as a result of rising populations and resource use per person.
Fig. 1-5, p. 11

28. We are living unsustainably
According to the 2005 UN Millenium Ecosystem Assessment, about 60% of the earth’s natural or ecosystem services have been degraded.
“Human activity is putting such a strain on the natural functions of Earth that the ability of the planet’s ecosystems to sustain future generations can no longer be taken for granted”
Summary statement of the Report

29. Pollution
Pollution is contamination of the environment by a chemical or other agent, such as noise or heat, that is harmful to health, survival, or activities of humans or other organisms.

30. Pollution Types Point sources are single, identifiable sources
the smokestack of a coal-burning power or industrial plant
a factory drainpipe, or
the exhaust pipe of an automobile
Nonpoint sources are dispersed and often difficult to identify.
pesticides blown from the land into the air
the runoff of fertilizers, pesticides, and trash from the land into streams and lakes

31. Pollution Cleanup We can clean up pollution or prevent it.
Pollution cleanup involves cleaning up or diluting pollutants after they have been produced
for example, water filters used to clean contaminated groundwater.
Pollution cleanup is usually more expensive and less effective.

32. Pollution Cleanup Drawbacks
It is only a temporary bandage as long as population and consumption levels grow without corresponding improvements in pollution control technology.
Cleanup often removes a pollutant from one part of the environment only to cause pollution in another. For example, we can collect garbage.
Once pollutants become dispersed into the environment at harmful levels, it usually costs too much to reduce them to acceptable levels.

33. Pollution Prevention
Pollution prevention reduces or eliminates the production of pollutants
for example, air purifying technologies used on smoke stacks for cleaner exhaust.
But we need both pollution prevention (front-of-the-pipe) and pollution cleanup (end-of-the-pipe) solutions.
Pollution prevention is another key to a more sustainable future.

34. The tragedy of the commons overexploiting shared renewable resources
Many open-access renewable resources have been environmentally degraded
Atmosphere
Open Ocean & its fish population
In 1968, the biologist Garrett Hardin called the degradation of openly shared resources the tragedy of the commons.

35. The tragedy of the commons overexploiting shared renewable resources
Possible solutions:
Use a shared renewable resource at a rate well below its estimated sustainable yield
by using less of the resource
regulating access to the resource, or both.
To convert open-access renewable resources to private ownership
This is not practical for global resources such as the atmosphere and the oceans.

36. Ecological footprints our environmental impacts
Ecological footprint is the amount of biologically productive land and water needed to supply a person or country with renewable resources and to recycle the waste and pollution produced by such resource use.
Per capita ecological footprint is the average ecological footprint of an individual in a given country or area.

37. Ecological footprints our environmental impacts
Ecological deficit means the ecological footprint is larger than the biological capacity to replenish its renewable resources and absorb the resulting wastes and pollution.
Humanity is living unsustainably
By depleting their natural capital instead of living off the renewable supply or income provided by it.
Footprints can also be expressed as number of Earths it would take to support consumption.

38. Per Capita Ecological Footprint (hectares per person)
Total Ecological Footprint (million hectares) and Share of Global Biological Capacity (%)
Per Capita Ecological Footprint (hectares per person)
United States
United States
2,810 (25%)
9.7
European Union
2,160 (19%)
European Union
4.7
China
2,050 (18%)
China
1.6
India
780 (7%)
India
0.8
Japan
540 (5%)
Japan
4.8
2.5
Unsustainable living
2.0
Number of Earths
1.5
Projected footprint
1.0
Figure 1.8: Natural capital use and degradation.
These graphs show the total and per capita ecological footprints of selected countries (top). In 2008, humanity’s total, or global, ecological footprint was at least 30% higher than the earth’s biological capacity (bottom) and is projected to be twice the planet’s biological capacity by around Question: If we are living beyond the earth’s renewable biological capacity, why do you think the human population and per capita resource consumption are still growing rapidly? (Data from Worldwide Fund for Nature, Global Footprint Network, Living Planet Report See
Ecological footprint
0.5
Sustainable living
1961
1970
1980
1990
2000
2010
2020
2030
2040
2050
Year
Fig. 1-8, p. 14

39. Ecological footprints our environmental impacts
Country
Total Ecological Footprint
(million ha)
Share of Global Ecological Capacity
(%)
Per Capita Ecological Footprint
(ha per person)
United States
2810 25
9.7
Europe
2160 19
4.7
China
2050 18
1.6
India
780 7
0.8
Japan
540 5
4.8

40. Ecological footprints our environmental impacts
Per Capita Ecological Footprint (ha per person) in the US is 9.7 and in China is 1.6.
On average each person in the U.S. consumes a lot more than someone in China.
To indefinitely sustain the resource use of the current human population, we would need the equivalent of 1.3 planet earths. If we continue on our current path, by around 2035 we will need 2 planet earths.

41. IPAT environmental impact model
In the early 1970s, scientists Paul Ehrlich and John Holdren developed the IPAT model.
It is a simple model showing how population size (P), affluence or resource consumption per person (A), and the beneficial and harmful environmental effects of technologies (T) help to determine the environmental impact (I) of human activities.
I = P x A x T

42. I = P x A x T

43. IPAT environmental impact model
Some forms of technology increase environmental impact by raising the T factor
Polluting factories, coal-burning power plants, and gas-guzzling motor vehicles
Some other technologies reduce environmental impact by decreasing T factor
Pollution control and prevention technologies, wind turbines and solar cells that generate electricity without polluting, and fuel-efficient cars.

44. IPAT environmental impact model
While the ecological footprint model emphasizes the use of renewable resources, this model includes the per capita use of both renewable and nonrenewable resources.
In most developing countries, the key factors in total environmental impact are population size and the degradation of renewable resources as a growing number of poor people struggle to stay alive.

45. IPAT environmental impact model
In more-developed countries, high rates of per capita resource use and the resulting high per capita levels of pollution and resource depletion and degradation usually are the key factors determining overall environmental impact.