Human dependence on the ocean

Lesson overview

This lesson emphasises that humans depend on the natural environment for their wellbeing, and introduces them to the concept of Ecosystem Services, and in particular how this relates to the ocean environment. It focuses on the benefits that healthy ocean ecosystems provide to us all, but coastal communities in particular, providing protection, food, and livelihoods.

Students are introduced to the potential impacts on all humans, but in particular coastal communities, of both increasing Global Climate Change and ocean resource exploitation.

Students are asked to relate these themes sustainability and justice, and start to clarify their attitudes and values.

Learning outcomes
  • Understand how nature provides things we need ‘ecosystem goods and services’ with a focus on the ocean
  • Discuss human impacts on ocean ecosystem goods and services services
  • Examine the challenges faced by coastal communities due to these activities
  • Reflect on the fairness and sustainability of ocean resource exploitation
Lesson steps

1. Introduction to ecosystem goods and services (20 minutes)

Introduce the learning objectives to the class using slide 2. Then move on to the opening activity, asking students to come up with as many things that they need for a happy and healthy life, using the think-pair-share method. Use slide 4 to support this, creating a long list on the board. Then using slide 5 ask students which of these come from nature. Introduce the terms ‘natural capital’ and ‘ecosystem goods and services’ using slides 6 and 7,

Students should then work in small groups to create a mind map of the ecosystem services provided by nature. Provide a large piece of paper or a whiteboard for students to work on. Encourage students to categorise ecosystem services into different types, such as food, water, clean air, recreation, and more. Allow students to use visuals or drawings to illustrate their mind maps.

Once the activity is complete, have students present their mind maps to the class. Discuss the similarities and differences between the groups' ideas and emphasize the importance of natural capital and ecosystem services in our lives.

2. Ocean ecosystem services (10 minutes)

Use the slides 9 to 15 to introduce the specific ecosystem services provided by ocean environments. Discuss the importance of these services for human well-being. Students should then add any of these goods or services to their mind map that they have not already included.

3. Human Impacts on Ocean Ecosystem Services (10 minutes)

Use slides 17 and 18 to show students the value of the main ecosystem goods and services provided by the ocean. The figure of $74 trillion in value per year is 2.5 times as large as the US economy and roughly the same value as the GDP of the top 10 largest economies. The ocean value could be even greater, as the last systematic calculation was conducted using 2011 figures and published in 2014.

The graph breaks down the ecosystem services in more detail, and shows which type of ocean ecosystem provides these services. As an extension, ask students whether anything surprises them or needs clarifying. Students may ask what the figures mean, such as $20 trillion worth of waste treatment. This figure is an estimate of what it would cost for artificial equivalents. For waste treatment, this may be building sewage treatment plants, for erosion prevention this might be building sea defences.

Ask students what they think might happen to the value of these services if human activity affected ocean habitats.

Use the Student Sheet Impact on ocean ecosystem services to highlight some of the main areas of human impact on the ocean. Students will then work to summarise this content into a cause and effect diagram. A worked example is on slide 20. Depending on students’ knowledge also provide them with a summary of ocean ecosystem services on Student Sheet Ocean ecosystem services.

4. Coastal Communities: At the Sharp End (15 minutes)

Explain the dependence of coastal communities on ocean ecosystem services for their livelihoods and well-being. Then introduce case studies of coastal communities facing challenges due to the degradation of ocean ecosystems (tropical and polar examples). Students should work in groups to choose one of the two case studies (tropical or polar) and present their findings to the whole class. Prompt questions are included on the Student Sheets and this work can be continued as home learning.

5. Reflection: Fair and Sustainable Resource Exploitation (5 minutes)

The lesson ends with a plenary discussion asking students to reflect on their opinion about the fairness of marine resource exploitation from the perspective of coastal communities and, indeed, the whole of humanity. It is desirable to extend the discussion to consider non-human nature as well (i.e. do humans have the right to exploit the marine environment in ways that are damaging to other species and marine habitats and environments).