A changing landscape Chapter 6 Section 1

The Effect of Human Activity How do our daily activities affect the environment? What happens when a growing human population does not adequately manage natural resources that are both vital and limited?

Living on Island Earth We affect our environment when we obtain food, eliminate waste products, and build places to live. These effects, along with noticing limited resources, can be most obvious on islands such as Hawaii because anything not locally available must be imported. Today, human activity has used or altered roughly half of all the land that’s not covered with ice and snow, so we cannot readily find more resources as easily as we could a century ago.

Living on Island Earth Humans affect regional and global environments through agriculture, development, and industry in ways that have an impact on the quality of Earth’s natural resources, including soil, water, and the atmosphere.

Agriculture One of the most important inventions in human history. Modern practices have enabled farmers to double world food production over the last 50 years. Monoculture: practice of clearing large areas of land to plant a single highly productive crop year after year (like soybeans). This impacts natural resources, including fresh water and fertile soil. Fertilizer production and farm machinery also consume large amounts of fossil fuels.

Development/Industrial Growth The growth of cities and suburbs is tied to the high standard of living that Americans enjoy, but those come with environmental effects. Dense human communities produce a lot of waste, which, if not disposed of properly, affect air, water, and soil resources. Society was transformed by the Industrial Revolution of the 1800s, providing conveniences from clothing to electronic devices. These, of course, require a lot of energy—we get most of this energy by burning fossil fuels. Not only are these affecting the air, but waste gets dumped into water and soil as well.

Ecosystem Goods and Services Some ecosystem goods---like breathable air and drinkable water—are so basic that we take them for granted. In many places, drinkable water is provided naturally by streams, rivers, and lakes, but if that water is polluted or damaged, cities and towns must pay for mechanical or chemical treatment to provide safe drinking water.

Renewable/Nonrenewable Resources Renewable resource: can be produced or replaced by a healthy ecosystem. Ex: A single southern white pine can grow in place of an old tree that dies or is cut down. Nonrenewable resource: cannot be replenished by natural processes within a reasonable amount of time. Ex: Fossil fuels are formed from buried organic materials over millions of years. When existing deposits are depleted, they’re essentially gone forever.

Sustainable Resource Use Ecological science can teach us how to use natural resources to meet our needs without causing long-term environmental harm. Using resources in such an environmentally conscious way is called sustainable development. What should sustainable development look like?

Sustainable Development 1. It should cause no long-term harm to the soil, water, and climate on which it depends. 2. It should consume as little energy and material as possible. 3. It must be flexible enough to survive environmental stresses like droughts, floods, and heat waves/cold snaps. 4. Finally, it must take into account human economic systems as well as ecosystem goods and services. It has to do more than just help people survive—it has to help them improve their situation.