Science and the Environment Chapter 1

UNDERSTANDING OUR ENVIRONMENT Section one: UNDERSTANDING OUR ENVIRONMENT

Understanding the Environment The environment is everything around us. Nature Man made things Complex relationships that connect the world and us.

Understanding the Environment cont. Environmental Science is multidisciplinary. Involves many fields of study. Ecology Chemistry Geology Zoology/botany Paleontology Social sciences (economics, law, politics, etc).

Scientists and Citizens Many times, the science studied by professionals are the findings of everyday citizens. Three legged frogs of lakes in Minnesota were first discovered by middle school students.

Our Environment through time Environmental change is not a modern concept. Wherever humans hunt, grow food, settle, environmental change occurs. This is a painting of what Manhattan probably looked like 300 hundred years ago (A ‘blink’ in human history)

Our Environment through time For most of human history, people were hunter-gatherers. Small groups, migrated. Even today, they still exist in remote parts of the world. Modern hunter-gatherer group in New Guinea, island off the coast of Australia

Hunter-gatherers What are some ways that hunter- gatherers have impacted their environment? Hunting bison and other grazers May have lead to the disappearance of larger mammals. Helped to spread plants to areas where the plants didn’t exist. Set fires to prevent tree growth.

Agricultural Revolution Following the hunter-gatherer period. Collected seeds, domesticated animals. People stopped migrating and built farms. Population started to grow at an unprecedented rate. Grasslands, forests, and wetlands were replaced with farmland. Destroyed natural habitats.

Industrial Revolution Mid 1700’s the use of human and animal muscle and water power changed over to use of fossil fuels (coal, oil and natural gas). Greatly increased the efficiency of agriculture, industry, and transportation. Increased sanitation, nutrition and medical care. Populations grew Pollution increased Habitat loss increased In the 1900’s modern societies increased their use of artificial substances (plastics, fertilizers, pesticides)

Earth is a closed system Earth has a limited amount of resources. The only things that enter Earth’s atmosphere in large amounts are energy and the only thing to leave in large amounts is heat. Environmental problems can occur on different scales. Local, regional, or global.

The Agricultural and Industrial Revolutions Both allowed the human population to grow at a much faster rate then ever before. Development of modern medicine and sanitation systems perpetuated the problem of population growth. Before 1700 population stayed relatively constant. After 1700 human population grew at an exponential rate.

Human Population Growth

What are our main Environmental Problems? Resource depletion Renewable vs. nonrenewable resources. When does a resource switch from being renewable to non? Pollution What types are there? Biodegradable Pollutants- can be broken down by natural processes. Ex: Sewage and newspaper Nondegradable Pollutants- such as mercury, lead, some plastics Loss of biodiversity Number and variety of species. Where is the most/least biodiversity found on Earth?

THE ENVIRONMENT AND SOCIETY Section two: THE ENVIRONMENT AND SOCIETY

Tragedy of the Commons Discovered by Hardin He found that when animals were left to graze on common land, people tended to graze as many as possible which degraded land. He also found the opposite to be true: When common land was fenced off to individual owners, they only grazed as many animals as the land could support.

How do we share common goods? Hardin did not consider the point that humans are social beings. Together, we can plan, organize, consider scientific evidence, and propose solutions. What ever the solution, may override the needs of the individual, but will improve the environment for everyone in the long term.

Economics Supply and demand: Cost-benefits analysis: Risk assessment: The greater the demand for a limited supply of something the more that something is worth. What are some examples of supply and demand in today’s society? Cost-benefits analysis: Balances the cost of an action against the benefits one expects from it. Risk assessment: Depending upon who is evaluating the risk, the results may be different. Public views risk of nuclear power differently than the scientific communiy.

Developed vs. Developing Higher average incomes Slower population growth Diverse industrial economies Stronger social support systems US, Japan, countries of Western Europe… Lower average incomes Simple and agriculturally based incomes Rapid population growth Parts of Africa, India, middle East…

Population and Consumption Two root problems: Human population in some areas is growing too quickly for the local environment to support it. People are using up, wasting, or polluting many natural resources faster than they can be renewed. One way to express the differences in consumption between nations is an Ecological Footprint. Calculation of the amount of land and resources needed to support one person from a particular country.

Sustainability and Stewardship Sustainability: human needs are met in such a way that a human population can survive indefinitely. Stewardship: The careful and responsible management of something entrusted to one’s care (usually not at their own benefit).