APES Intro Lecture. World’s Population Population Size Population Size Growth Characteristics (exponential, logistic) Growth Characteristics (exponential,

APES

Intro Lecture

World’s Population Population Size Growth Characteristics (exponential, logistic)

• Growth Rate• Doubling Time – Rule of 70

Population Distribution• Developed Countries• Developing Nations

Resource Distribution• Developed Countries• Developing Nations

Overpopulation• People • Resource

Population Growth MDC v LDC

Natural Resources

Perpetual Renewable Nonrenewable

• Fossil fuels• Mineral

Metallic Non metallic

• Strategic minerals

Some Sources Are Renewable and Some Are Not

Natural Resource• Anything we obtain from the

environment to meet our needs• Some directly available for use: sunlight• Some not directly available for use:

petroleum

Perpetual resource• Solar energy

Some Sources Are Renewable and Some Are Not (2)

Renewable resource• Several days to several hundred years

to renew• E.g., forests, grasslands, fresh air, fertile

soil

Sustainable yield• Highest rate at which we can use a

renewable resource without reducing available supply

Some Sources Are Renewable and Some Are Not (3)

Nonrenewable resources • Energy resources• Metallic mineral resources• Nonmetallic mineral resources

Reuse

Recycle

Ecological Footprints: A Model of Unsustainable Use of Resources

Ecological footprint: the amount of biologically productive land and water needed to provide the people in a region with indefinite supply of renewable resources, and to absorb and recycle wastes and pollution

Per capita ecological footprint

Unsustainable: footprint is larger than biological capacity for replenishment

Total Ecological Footprint (million hectares) and Share of Global Biological Capacity (%)

Per Capita Ecological Footprint (hectares per person)

United States 2,810 (25%) United States 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

2.5Unsustainable living2.0

1.5Projected footprint1.0

Nu

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0.5

Ecological footprint Sustainable

living

1961 1970 1980 1990 2000 2010 2020 2030 2040 2050

Year

0

Points of View

Neo malthusian Cornucopian Anthropocentric Biocentric Ecocentric Stewardship Environmental Justice

Different Views about Environmental Problems and Their Solutions

Environmental ethics: what is right and wrong with how we treat the environment

Planetary management worldview• We are separate from and in charge of nature

Stewardship worldview• Manage earth for our benefit with ethical

responsibility to be stewards Environmental wisdom worldview

• We are part of nature and must engage in sustainable use

Principles

Sustainability• Carrying Capacity• Ecological Footprint

Spaceship Earth Tragedy of the Commons (Hardin) Basic Law of Ecology Gaia Hypothesis Precautionary Principle - When there is a great threat of

serious environmental damage, we should not wait for scientific proof before taking precautionary steps to prevent potential harm

Feedback / Feedback Loops Feedback- when one part of the system changes

Those changes affect another part of the system Which affects the first change

Negative feedback- an increase in output leads to a later decrease Self-regulating, or stabilizing

Positive feedback- an increase in output leads to a further increase in the output Destabilizing

Example

Scientific Method

Observation Hypothesis / Prediction (If ….., then…..) Experimental design

• Step by step• Relates to the hypothesis• Clearly identify variables

Control Independent (manipulated) Dependent (responding)

Data Collection - Quantitative Repeatability Data Analysis Error Analysis Conclusions

Energy

Energy = ability to do work Types of Energy KE, PE, Solar, Nuclear, Chemical, Electrical,

Mechanical, Thermal, etc. Heat = total energy Temperature = proportional to the average kinetic energy Power = rate of doing work; rate of energy consumption Energy Quality

• High• Low

Energy Efficiency• Simple : [(Eout)/(Ein)] * 100 (% efficiency)

• Net Energy : (Eout) – ALL energy inputs (mining resource, processing, transportation, losses in use)

Productivity• GPP – gross primary productivity• NPP = GPP – R (R = respiration) Net primary productivity

Laws / Concepts Relating to Energy Flow

First Law of Thermodynamics – Law of Conservation of Energy• Conservation of Energy implies conservation of matter (b.c.)• E = mc2 (Einstein)

Second Law of Thermodynamics – Law of Degradation of Energy – Entropy No conversion of energy is 100% efficient

Maximum Power Principle the system that gets the most energy and uses it most efficiently will survive in competiton with others (Nature tends to shorten the food chain)

Thermal gradient heat flows, spontaneously, from warmer to cooler.

Possible or Impossible?

Ways to Transmit Energy

Conduction Convection Radiation

Basic Chemistry Concepts

Atom – fundamental particles Nucleus – dense, positively charged center

• Protons positively charged• Neutrons neutral

Electrons outside the nucleus (orbit the nucleus); negative charge- Atomic number = number of protons Mass Number = number of protons + neutrons Isotope = same atomic number, different mass number Allotrope = more than one form is stable (O2, O3) Ions = charged particles; lost or gained electrons

Radioactive Isotopes• Uses• Half-life• Emissions

a – alpha least penetrating, equivalent to a helium nuclei b – beta equivalent to an electron g – gamma most penetrating

Nuclear Reactions• Nuclear Fission – larger particles to smaller particles• Nuclear Fusion – smaller particles to larger particles• Nuclear Waste

High level Low level

Chemistry Con’t

Bonding• Ionic – metals + non metals; transfer electrons• Covalent – non metal + non metal; share electrons, form bonds• Hydrogen bonding – intermolecular force; N, O, and F only

Compounds• Inorganic• Organic• Diatomic – H, O, N, F, Cl, Br, I• Biologically Important Organic Compounds

Carbohydrates Lipids Nucleic Acids Proteins

• Acids / Bases pH scale generally 0 – 14 pH = -log [H+]

pH Calculations

Logarithm Calculations (base 10)Log10(x) = Y 10Y = x

pH = -log[H+]If the [H+] = 10-3, the pH = -log[10-3] = 3