Name: Date: Chapter 1 Notes Science and the Environment Section 1 Understanding Our Environment What is Environmental Science? (p. 5) Environmental science = the study of the,, and surrounding an organism or a community, which ranges from a small area to Earth s entire biosphere. It includes the study of how interact with the. Everything is connected to everything else! The Goals of Environmental Science (p. 6) A major goal of environmental science is to understand and solve. To accomplish this goal, environmental scientists study two main types of interactions between humans and their environment: 1. The use of. 2. How our alter our environment. Many Fields of Study (p. 6) Environmental science is an science, which means that it involves many fields of study. Important to the foundation of environmental science is. Ecology = the study of how things interact with each other and with their environment. Examples of other fields of study that contribute to environmental science include: Our Environment Through Time (p. 9) Wherever humans have,, or, they have changed the environment. 1
Example: the immense environmental change on Manhattan Island over the last 300 years was just a blink in human history. Hunter-Gatherers (p. 9) Hunter-gatherers are people who obtain food by collecting and by hunting wild or scavenging their remains. Hunter-gatherers affected their environment in many ways. Examples include: Native American tribes hunted. The tribes also set to burn prairies and prevent the growth of trees for ease in hunting bison. In North America, a combination of rapid and by hunter-gatherers may have led to the disappearance of some large species. The Agricultural Revolution (p. 10) Agriculture = the raising of and for food or for other products that are useful to humans. The practice of agriculture started in many parts of the world over years ago. The change had such a dramatic impact on human societies and their environment that it is often called the. The agricultural revolution Allowed human to grow at an unprecedented rate. o As populations grew, they began to concentrate in areas, placing increased pressure on environments. Changed the we eat. Evolved wild into the plants we grow and eat today. Destroyed many, such as grasslands, forests, and wetlands, and replaced them with farmland. o Caused soil loss, floods, and water shortages. o Much of the farmland was poorly farmed and no longer. o The technique was one of the earliest ways that land was converted to farmland. 2
The Industrial Revolution (p. 11) The Industrial Revolution (beginning in the mid 1700s) involved a shift from sources, such as animals and running water, to, such as coal and oil. Fossil fuel use changed society and greatly increased the efficiency of,, and. Improving the Quality of Life (p. 11) The Industrial Revolution introduced many positive changes: productivity increased, and,, and care vastly improved. It also introduced many new environmental problems, such as and. In the 1900s, modern societies began to use substances in place of raw animal and plant products. o As a result, we now have materials such as,, and. These products made life easier, but we do not fully understand the environmental problems they present. Spaceship Earth (p. 12) Earth can be compared to a spaceship traveling through space that cannot dispose of its or take on new. Earth is essentially a. o The only thing that enters the Earth s atmosphere in large amounts is and the only thing that leaves in large amounts is. o This type of closed system has some potential problems: Some resources are limited, and as the population grows, the resources will be used more. Possibility of producing more quickly than we can dispose of them. 3
Environmental problems can occur on different scales: Population Growth (p. 13) The agricultural revolution, the Industrial Revolution, modern medicine, and sanitation all allowed the human population to grow faster than it ever had before. In the past 50 years, nations have used vast amounts of to meet the world s need for food. Producing enough food for such a large population has environmental consequences, such as and. Most scientists think that the human population will almost in the 21 st century before it begins to. We can expect the on the environment will continue to increase as the human population and its need for food and resources grows. What are Our Main Environmental Problems? (p. 14) Environmental problems can generally be grouped into three categories: 1. 2. 3. Resource Depletion (p. 14) Natural resources = any natural materials that are used by humans (e.g., water, petroleum, minerals, forests, animals). They are classified as either renewable or nonrenewable resources. o o Renewable resources can be relatively quickly by natural processes. Nonrenewable resources form much than they are consumed. Renewable Resources Nonrenewable Resources 4
Resources are said to be when a large fraction of the resource has been used up. Once the supply of a nonrenewable resource has been used up, it may take of years to replenish it. Renewable resources, such as, may also be depleted, causing in some areas. Pollution (p. 14-15) Pollution = an undesired change in the natural environment (air, water, or soil) that affects the health, survival, or activities of humans or other organisms. Much of the pollution that troubles us today is produced by and the of. There are two main types of pollutants: Biodegradable pollutants, which can be broken down by processes. o Includes human sewage and newspaper. o Degradable pollutants are a problem only when they faster than they can be broken down. Nondegradable pollutants, which be broken down by natural processes. o Includes mercury, lead, and some plastics. o Do not break down easily; can build up to levels in the environment. Loss of Biodiversity (p. 15) Biodiversity = the number and variety of species that live in an area. The organisms that share the world with us can be considered. We depend on them for, the we breathe, and for many other things. Only a fraction of all the species that once roamed the Earth are alive today, and many are. Extinction is a natural process, and several large-scale extinctions (or extinctions) have occurred throughout Earth s history. 5