Chapter 1: Introduction Environmental Problems, Their Causes, and Sustainability

Earth Rise

Environmental Science Understand how natural world works Understand how human systems interact with natural system Accurately determine environmental problems Develop and follow a sustainable relationship with natural world

Themes Sustainability: A process can continue indefinitely without depleting resources used *no sacrifice to future generations* Stewardship: Caring for something that does not belong to you Science: Use the scientific method and question authority Ecosystem Capital: Essential goods and services like food, water, and fuel Policy and Politics: Human decisions determine what happens to the natural world Globalization: The interconnectedness of human activities, ideas, and cultures

Rachel Carson was a scientist who wrote Silent Spring in It addressed the growing use of pesticides (DDT) and their unpredicted effects on song birds. Original users of pesticides did not know that the poisons used to kill insects would accumulate in other living things and kill them too. BIOACCUMULATION

Talking Points (pg.3 Raven) Environmental sustainability is based (in part) of what key ideas? Understanding effects of our action on health and well-being of all natural systems. Earth’s resources are finite. Understand ALL costs to environment/society associated with what we consume. We must all share the responsibility of environmental sustainability.

Evidence We are not Operating Sustainably 1.Using non-renewable resources as if in infinite supply. 2.Using renewable resources faster than they can replenish. 3.Introducing toxins faster than Earth can absorb them. 4.Population growth continues to rise, despite finite resources.

World Population Graph

Environmental Science Humanities relationship between: 1.Other living organisms and 2.Our nonliving physical environment.

IPAT Model I = P X A X T I = Impact to environment P = population A = affluence/amount of resources consumed T = environmental effect of technology used to obtain and consume the resource

Endocrine Disruptors Industrial/agricultural chemicals that mimic or interfere with the endocrine system (hormones) in people and wildlife. Examples: DDT, dioxine, heavy metals, kepone, dieldrin, chlordane, endosulfan and plastics (phthalates).

Hormones Hormones are chemical messengers that regulate growth, reproduction and other biological functions. Endocrine disruptors mimic, estrogen (F), androgen (M) and many thyroid hormones.

Juvenile Alligators Lake Apopka Lake contaminated in 1980’s with DDT and agricultural chemicals Feminization of males 40% hatch rate, ½ die within 10 days

Georges Bank Fishery Closed In 1994, US Department of Commerce closed two large sections of the 16, 500 km 2 fishery off the coast of New England due to overfishing.

Georges Bank Fishery Closed

Easter Island Home Page and Music

Map of Easter Island Area km2 In the 4 th century A.D there were approximately 10,000 people living here

Use of resources Natural Resources Fresh water Trees Fish Brought by settlers Chickens Sweet potatoes Taro Yams Used for: Building houses Food Clothing Technology –Stone statues (moai) –Needed many trees to move the statues

Moai There are 887 moai on Easter Island Average Height: feet (4.05 meters) some are more than 20 feet (6 meters) Average weight: tons

Dutch explorers arrive in people left Constant war Few of the natural resources left What happened!

4 Global trends: A.Population growth and economic development B.Decline of ecosystems C.Global atmospheric changes D.Loss of biodiversity

A. Human population growth More than 6.6 billion people currently We are adding 76 million people per year increase pop → increase need for resources Note: This graph is from These predictions are based on a faster growth rate. Carrying capacity is higher in this graph.

Different lifestyles have different demands on the environment Developed (industrialized) countries like America hot running water more than one car per family -VS- Developing countries like Tanzania hunting/gathering Firewood for heat and cooking 1 billion + people live in poverty

B. Soil degradation Demand for food destroys the soil –erosion –minerals in soil are depleted –salinization –increased use of pesticides –overuse of fresh water

C. Global Atmospheric Changes Global Warming –CO 2 produced from fossil fuel burning acts like a blanket around the earth. –Plants take CO 2 out of the atmosphere through photosynthesis 6CO 2 +6H 2 O => C 6 H 12 O 6 Ozone depletion –Chemicals released from the surface of the earth destroy our ozone shield. –No stratospheric ozone, no protection from the UV rays of the sun.

Carbon Dioxide Levels

Ozone

D. Loss of Biodiversity Habitat destruction leads to a loss of many species starting with the plants exact # of species lost is unknown because not all species are identified strong ecosystems need biodiversity % of all prescription drugs from natural resources Wild species keep domestic species vigorous Aesthetics

A sustainable future is possible Nutrition levels and life expectancy are rising Population growth rates are falling It is cool to be “green” YOU are taking this class