Science & the EnvironmentSection 1: Understanding Our Environment

Miss Napolitano/Mrs. RodriguezEnvironmental Science

What is Environmental Science?

• Environmental science – the study of the air, water, & land surrounding an organism or a community, which ranges from a small area to Earth’s entire biosphere.

• Includes the study of the impact of humans on the environment

Many Fields of Study

• Envi Sci is interdisciplinary – involves many fields of study

• Includes:• Ecology – study of interactions of living organisms with

one another and with their environment

• Biology – the study of living things

• Chemistry – the study of chemicals and their interactions

• Physics – the study of matter and energy

Contributing Fields of Study

Scientists as Citizens, Citizens as Scientists• Studying the environment makes a healthy,

productive society

• Observations of nonscientists are the first steps toward addressing an environmental problem

Our Environment through Time• Humans change their environment!• Ex: Manhattan

news.nationalgeographic.com

First Impact: Hunter-Gatherers

• Hunter-gatherers – people who obtain food by collecting plants & hunting wild animals• Example: Native Americans• Hunted buffalo• Burned prairies to prevent tree growth

• May have led to disappearance of large mammal species in North America, including:• Giant sloths• Giant bison• Mastodons• Cave bears• Saber-toothed cats

The Agricultural Revolution

• Agriculture – raising of crops & livestock for food or other products useful to humans• Began 10,000 years ago• Caused populations to boom & concentrate in small

areas• Grasslands, forests, & wetlands replaced with farmland

using the slash-and-burn technique• Poorly farmed, soil is no longer fertile

• Caused soil loss, floods, & water shortages• Changed food that we eat• Wild plants – “nature plants”• Domesticated plants – selectively bred for certain qualities

Selective Breeding in Corn

The Industrial Revolution

• Shifted from natural energy sources to fossil fuels• Ex: Animals & running water coal & oil

• Increased efficiency of agriculture, industry, & transportation• Ex: motorized vehicles = cheap transportation over long

distances• Factories produced cheaper goods than goods made by

hand• Farm machines reduced human labor

• Caused populations to grow in urban areas

Improving the Quality of Life

• Improvements after the industrial revolution:• Agricultural productivity• Sanitation• Nutrition• Medical care

• New environmental problems:• Pollution• Habitat loss• Artificial substances replaced raw animal & plant products• Plastics, artificial pesticides, & fertilizers

Spaceship Earth

• Spaceship Earth – Earth is like a spaceship traveling through space• Cannot dispose of its waste or take in new supplies

• Earth = closed system• Large scale, the only thing that enters the atmosphere is

energy from the sun• Large scale, the only thing that leaves the atmosphere is

heat

Environmental Problems

• Local• New landfill in the community

• Regional• Polluted river 1000 miles away affecting the region’s water

• Global• Depletion of the ozone layer

• Main environmental problems:• Resource depletion• Pollution• Loss of biodiversity• Biodiversity – variety of organisms in a given area

Population Growth

• Humans are growing faster than ever before, thanks to the Industrial Revolution, modern medicine, & sanitation

• More humans = more food = problem!

• Human population expected to double before stabilizing