Exponential Growth – growth at a fixed percentage per unit time; why is it important?
Important because this predicts that populations will grow to enormous numbers à usingup resources and creating more pollution
The environment is the sum of the biotic (living) and abiotic (non-living) factors that affect an organism; what are some of the biotic and abiotic factors that affect you?
Biotic factors: plants and algae (producers: produce their own food), animals (consumers:get their food by eating plants or other animals), bacteria (decomposers: break downdead remains of plants/animals and recycles them into the soil or water for reuse)• Abiotic factors: water, air, nutrients, solar energy
Much of what we talk about in this class deals with _____, the science of relationships between living organisms and their environments (both biotic and abiotic components).
In this class we will deal mostly with renewable resources, certainly an important part of environmental science. Remember that _______ is not a science, it is a social movement, usually involving concerned activists working to pass legislation, enforce regulations, and find sustainable solutions to environmental problems, hopefully based on research by environmental scientists.
In the context used in the book, environmental science and natural resource conservation areone in the same; how nature works, how the environment affects us, how we affect theenvironment, and how we can live more _____ without degrading our life-supportsystem.
is the science of relationships between living organisms and their environments.
is not a science, it is a social movement, usually involving concerned activistsworking to pass legislation, enforce regulations, and find sustainable solutions to environmental problems.
is the ability of natural systems to adapt indefinitely; more specifically from a humanstandpoint, it is the ability of a system to provide resources to current populations without degrading the ability of those systems to provide resources for future generations.
Figures 1-3 and 1-4. The book emphasizes the path to sustainability and natural capital, which includes the resources and processes that support all living organisms on the planet. What kind of “trade-offs” do we make on this path? How do humans affect the quality and quantity of our natural capital?
- Trade-offs: ex: to provide wood for making paper, we can promote the planting of tree plantations in areas that have already been cleared or degraded
- Human effects on quality and quantity of natural capital: ex: clearing mature forests much faster than nature can re-grow them
– resource conservation, and the problems facing a growing human population, can easily be
visualized as a savings account...
- Lesson: protect your capital and live off the income it provides. Deplete waste, or squander your capital, and you will move from a sustainable to an unsustainable lifestyle
- We are living unsustainable by wasting, depleting, and degrading the earth’s natural capital at an exponentially accelerating rate
- Exponential growth of the human population – 2.6 people per second are currently being added to
- the world’s population!
Economic growth requires increasing levels of production and consumption, either by more people, or more per person. Can economic growth go on forever?
Economic growth: an increase in the capacity of a country to provide people with goods and services. Accomplishing this increase requires population growth (more producers and consumers), more production and consumption per person, or both.
The GDP (gross domestic product) is the measure of economic growth among nations – how is it calculated?
GDP is the annual market value of all goods and services produced by all firms and organizations, foreign and domestic, operating within a country
It is usually divided by population size to yield the per capita GDP so we can compare among nations. What is the GDP-PPP and why do countries differ in the world ranking of GDP and GDP-PPP?
GDP-PPP: Gross domestic product – purchasing power parity. GDP and GDP-PPP rankings differ because GDP-PPP accounts for differences in purchasing power for basic necessities
Figures 1.5 and 1.6 – What are the differences among developed and developing countries, both in terms of population characteristics and geographic distribution?
- Developed countries: smaller percentagen of world’s population, small percent of population growth, large percent of wealth and income, large percent of resource use, large percent of
- pollution and waste, small percent of increasing level of poverty
- Developing countries: large percentage of world’s population, larger percent of population growth, small percent of wealth and income, small percent of resource use, smaller percent of pollution and waste, larger percent of increasing poverty levels
- Increasing poverty levels: due to unfavorable climates, geological bad luck in terms of fertile soils, minerals, and fossil fuel supplies
Talk about the importance of this:
Doubling time can be calculated as 70 ÷ annual percentage growth rate; human population growth rates may seem low (0-4%), but doubling times show how these low rates can still result in huge population increases in a relatively short time
doubling times for human populations are important, but what is most important is not just how fast the human population is growing, but how fast we can find solutions to our environmental problems as our population grows.
What are examples of perpetual Resourses?
- Perpetual resources: essentially inexhaustible resource on a human time scale because it is renewed
What are examples of renewable resourses?
- renewable resources: resources that can be replenished rapidly (hours to several decades) through natural processes as long as it is not used up faster than it is replaced.
- Treesin forests
- Grasses in grasslands
- Wild animals
- Fresh surface water in lakes and streams
- Most groundwater
- Fresh air
- Fertile soil
- **if such a resource is used faster than it is replenished, then it can be depleted and converted into a non-renewable resource
What are some examples of non-renewable resourses?
- non-renewable resources: resources that exist in a fixed amount (stock) in the earth’s crust and have the potential for renewal by geological, physical, and chemical processes taking place over hundreds of millions to billions of years.
- **we classify these resources as exhaustible because we are extracting them at a much faster rate than they are formed
Sustainable yield is...
highest rate at which a potentially renewable resource can be used indefinitely without reducing its available supply
Environmental degradation is...
depletion or destruction of a potentially renewable resource such as soil, grassland, forest, or wildlife that is used faster than it is naturally replenished. If such use continues, the resource becomes nonrenewable (on a human time scale) or nonexistent (extinct)
How is sustainable yield related to environmental degradation? (Hint: think about the savings account)
RELATED BECAUSE: there is a fine line between the two. If we work within the sustainable yield usage frame, than we will not have environmental degradation. However, if we surpass the sustainable yield usage, then we will be environmentally degrading.
Common property is... give examples
- resource that people normally are free to use; each user can deplete or degrade the available supply. Most such resources are renewable and owned by no one.
- Clean air
- Fish in parts of the ocean not under the control of coastal country
- Migratory birds
- Gases of the lower atmosphere
- Ozone content of the upper atmosphere (stratosphere)
Explain the "Tragedy of the Commons"
- depletion or degradation of a potentially renewable resource to which people have free and unmanaged accessDepletion of commercially desirable fish species in the open ocean beyond areas controlled by
- coastal countries
Use of common property resources often results in the Tragedy of the Commons – why? One solution that has been proposed is to privatize resources, which assumes that owners will take care of
their property – why is this not necessarily a good idea?
- Use of common property resources often results in the tragedy of the commons because the use of the common property is unregulated therefore people are on their own to use as much of it as then want, leading to tragedy of the commons when the supply is gone
- Not a good idea to privatize resources because there will be those that will take perfect care of their resources, and others that will not.