Chapter 6

Overview

Diversity & Conservation

• Importance to nature

• Importance to people– Oxygen– Diet– Medicines

Loss of Diversity

• Threatened Species

• Endangered Species

• Extinction of Species

•Alabama -- 115 listings •Alaska -- 11 listings •Arizona -- 60 listings •Arkansas -- 29 listings •California -- 300 listings •Colorado -- 33 listings •Connecticut -- 19 listings •Delaware -- 20 listings •District of Columbia -- 3 listings •Florida -- 111 listings •Georgia -- 66 listings •Hawaii -- 317 listings •Idaho -- 25 listings •Illinois -- 28 listings •Indiana -- 29 listings •Iowa -- 14 listings •Kansas -- 15 listings •Kentucky -- 47 listings •Louisiana -- 26 listings

•Maine -- 15 listings •Maryland -- 26 listings •Massachusetts -- 24 listings •Michigan -- 21 listings •Minnesota -- 13 listings •Mississippi -- 38 listings •Missouri -- 25 listings •Montana -- 17 listings •Nebraska -- 13 listings •Nevada -- 38 listings •New Hampshire -- 12 listings •New Jersey -- 23 listings •New Mexico -- 42 listings •New York -- 26 listings •North Carolina -- 63 listings •North Dakota -- 8 listings •Ohio -- 26 listings •Oklahoma -- 20 listings •Oregon -- 54 listings

•Pennsylvania -- 17 listings •Rhode Island -- 17 listings •South Carolina -- 42 listings •South Dakota -- 12 listings •Tennessee -- 96 listings •Texas -- 91 listings •Utah -- 47 listings •Vermont -- 8 listings •Virginia -- 71 listings •Washington -- 41 listings •West Virginia -- 21 listings •Wisconsin -- 16 listings •Wyoming -- 18 listings •American Samoa -- 4 listings •Guam -- 12 listings •Northern Mariana Islands -- 13 listings •Puerto Rico -- 75 listings •Virgin Islands -- 13 listings •Outlying Caribbean Islands -- 0 listings •Outlying Pacific Islands -- 0 listings

Endangered Species/State

2004 Data

Threats to Biodiversity

• Habitat Loss• Habitat Fragmentation

– Biotic Issues– Abiotic Issues

• Habitat Degradation– Air Pollution– Water Pollution– Land Pollution

Exotic Species• Non-native

organisms that “move-in” to a particular area

• There can be a lack of competitors = exponential growth

• Can take over the niches of native species

Example: Page 124

Conservation• Sustainable use:

– Use what you need, but don’t damage the ecosystem

Is this a good example of sustainable use?

Humans & The Environment

• Pest Control– Benefits vs. Problems– EX: DDT

Humans & The Environment

• Ozone (O3) Depletion

– O3 forms a “good layer” around the Earth

– CFC release is breaking down the protective ozone layer

– UV rays increase skin cancers & other cell mutations to plants & animals!

How is Acidity Measured?• When we observe acid

rain, acidity is measured in units called pH.

• The pH scale is from 0 to 14– pH 7 indicates neutral– higher pH numbers =

alkalinity (base)– smaller numbers = acid

• We’ll do more on pH in the “Biochemistry” chapter

Natural Acid Precipitation• CO2 combines with

water to form a weak acid H2CO3 (carbonic acid)

• But we are adding to the problem…– by adding nitric and

sulfuric acids

Look at the “clean rain” – it’s already slightly acidic???

Effects of Acid Precipitation• In Japan, rain which registers pH 5.6 or less is considered acid rain; some 80-

90% of the rain that falls in Japan in a year is acid rain. • In Japan, acid rain with acidity equal to lemon juice has been observed at

Mount Tsukuba in 1984 (pH 2.5) and at Kagoshima in 1987 (pH 2.45). • The problem is even more serious in N. America and Europe.

– In those regions, forests are withering and lakes becoming uninhabitable to fish, and stone structures such as buildings and bronze statues are being damaged by corrosion.

1970 1985

Humans & The Environment

• Global Warming– “The Greenhouse Effect”

– Fossil fuels give off lots of CO2

– This builds a blanket around the earth– It is predicted that the Earth temp. will

increase ~50C before 2050 = Ice age????

Carbon Dioxide Increase

• Carbon dioxide levels fluctuate seasonally

• The average level is steadily increasing

• Burning of fossil fuels & deforestation are

contributing to the increase

Greenhouse Effect

• Greenhouse gases impede the escape

of heat from Earth’s surface

Global Warming

• Long-term increase in the

temperature of Earth’s lower

atmosphere

Other Greenhouse Gases

• CFCs - synthetic gases used in plastics

and in refrigeration

• Methane - produced by termites and

bacteria

• Nitrous oxide - released by bacteria,

fertilizers, and animal wastes