Chapter
5
Oceans and Coasts
By Susan Stempleski
This chapter outlines a 50-minute lesson that explores the present state of the world’s oceans and coasts and the important role that humans play in maintaining the life and health of oceans and coastal areas. The lesson begins with a warm-up activity in which students discuss the importance of saving the world’s oceans. Then, they listen to a reading and complete a task sheet about the state of the world’s oceans and coasts. Next, they review the reading and have a class discussion on causes and types of marine pollution. The lesson ends with an activity in which students list ways their own activities affect the oceans and then brainstorm actions they can take to reduce marine pollution.
Through listening, speaking, and reading activities centered on the topic of marine pollution, students improve their language skills by learning and using new vocabulary and concepts related to the topic. Some teachers may choose to present the activities described in the section on Classroom Applications in a single 50-minute lesson. Others may wish to combine the activities with some of the materials outlined in the section on Internet Resources to create a longer lesson or a more extensive unit of several related lessons.
State of the World’s Coasts
Most of the world’s coasts are polluted.
The two biggest and most serious causes of coastal pollution are sewage disposal, and sedimentation from land-clearing and construction projects.
Pollution is changing coastal habitats and destroying fish and other wildlife.
State of the World’s Oceans
The open ocean is cleaner than the world’s coastal areas because most pollutants come from land and remain in water near the coastal areas.
Pollution from litter and chemicals is present in all the world’s oceans, from coastal areas to the open ocean.
Most of the trash and pollutants produced by human activities end up in the world’s oceans. Sometimes these materials are directly drained or dumped into the ocean, either on purpose or, as in the case of oil spills, by accident. Some pollutants (e.g., chemicals in smoke) first enter the atmosphere and later end up in the ocean. A lot of marine pollution comes from rivers and streams that empty into the oceans. These rivers carry sewage, industrial waste, overflow from city streets, fertilizers and pesticides from farms, and sedimentation.
Types of Marine Pollution
There are six major types of pollution that affect the world’s oceans and coasts: sewage, litter, petroleum, synthetic chemicals, toxic metals, and radioactive materials.
SEWAGE dirties the water with organisms that cause diseases. People can become seriously ill from eating contaminated shellfish or by swimming in polluted water.
LITTER that people leave on land is the source of most of the plastic that ends up in coastal areas and oceans. Non-biodegradable plastics not only hurt fish, birds, seals, and other sea animals, but they also destroy the natural beauty of beaches.
PETROLEUM enters the oceans from oil spills or in the form of urban or industrial waste. This oil dirties beaches, kills animals, and causes problems for marine organisms.
SYNTHETIC CHEMICALS in the form of pesticides and industrial chemicals affect all forms of life in the oceans, causing tumors, birth defects and other damage.
TOXIC METALS are present in only small amounts, except in a few remote areas.
RADIOACTIVE MATERIALS are present everywhere. Most of these are natural, but a few are caused by the testing of nuclear weapons.
