11
Soil degradation
1. SHORT SUMMARY
• Total duration of this lesson: 45 minutes
• What will the students learn?
o What the causes of soil degradation are.
o What solutions can delay/stop soil degradation and help the enrichment of soil
fertility.
• What will the students do during this lesson?
o Watch videos, get to know sustainable agricultural entrepreneurs and companies
and participate in a practical experiment, which will demonstrate the importance
of soil cover for the prevention of soil erosion and nutrient run off.
• What skills are the students going to improve?
o Analysis and synthesis of information
o Empathy and emotional intelligence
o Digital competence and Internet research skills
o Teamwork skills
o Holistic thinking and system thinking
o Responsibility
o Presentation and discussion skills
o Sustainability mindset
o Business analysis skills
o Reading comprehension
• Cross-curricular links:
o Biology
o Entrepreneurship / economics
o Geography
o Philosophy
o Information technologies
o English language
• Materials needed:
o Multimedia projector
o Laptop / computer with speakers
o Internet connection in the classroom (if there is no Internet in your classroom,
you can download the online videos in this lesson in advance and bring them on
a flash drive, or alternatively you can ask students to form groups and use their
smartphones/tablets in order to watch the videos)
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Soil degradation
Tell the students that the soil is the top layer of the Earth’s crust which is a medium of support
and nourishment of cultivated and self-sown plants, and is necessary for the circle of life on planet
Earth as it contributes to the growth of plants.
Taking into consideration these facts, as well as that only 10% of the soil is arable in combination
with its key role for the food chain, it is important to study the natural and anthropogenic causes
which lead to its degradation. Equally important is to give suggestions/solutions on an individual
and on a collective level that can lead to a reduction of this phenomenon and even to enrichment
of the soil fertility. Soil is the cornerstone of food security and agricultural development, thus its
restoration and conservation should become a major global priority.
You can use the photo below to illustrate what degraded soil looks like. You can either display it on
the multimedia projector or print it out in large format and place it on a visible place in the classroom.
Source: http://www.un.org/News/dh/photos/large/2011/October/20-10-2011-drylandcommunity.jpg
Ask the students:
• Do you know of any soils in your area that are degraded? (They might not look so severely
degraded as the photo above but that doesn’t mean they do not suffer from some form of
degradation.)
• What do you think might be the causes and consequences of soil degradation for people
and biodiversity?
• How important do you think is the quality of the food we eat for our health?
After collecting several answers and recording them on the whiteboard, proceed to the next section.
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(3 min.)
CORE
2. INTRO – THE GIST OF IT
Lesson 11
(10 min.)
CORE
3. THE THEORY
You can choose to present this section in one of two ways – through showing a video which will
develop students’ listening comprehension skills or through providing a text which will develop
students’ reading comprehension skills. Either way, the theory presented is one and the same.
1) Option 1: The theory through reading comprehension
Tell the students that they are going to read a text about soil degradation, which is available here:
http://greenfieldgeography.wikispaces.com/Soil+and+change. Ask them to read it individually and
to note down answers to the following questions, while reading:
• What is the definition of soil degradation?
• What are the different ways soil can get degraded?
• What does the map of soil degradation show?
• Why is soil important?
• Which human activities cause soil degradation?
• What are the natural causes of soil degradation?
• What are the consequences and problems caused by soil degradation?
• Which are two of the possible solutions of soil degradation which you think will be most
effective?
2) Option 2: The theory through listening comprehension
Tell the students that they are going to watch a video on soil degradation. Tell them to pay attention
to the following questions (which you may have written down on the whiteboard / flipchart):
“The Value of Soil”: https://www.youtube.com/watch?v=403sT9CGRl0 (4:45 min.)
• Why is productive land becoming scarce? (Because a lot of land is being used for the breeding of animals and for the production of crops for bio-fuels.)
• What are the reasons for soil degradation? (We try to extract the maximum yield from soil,
not being aware of how to take care of it properly. We overuse land and cultivate unsuitable land. Other reasons are cutting down forests, overgrazing, monocultures, salination,
overuse of fertilizers and chemicals, and farming on sloping ground leading to soil erosion.
Climate change also contributes to soil degradation, and soil degradation in turn worsens
climate change – remember the negative feedback loops from system theory.)
• How fast does top soil “grow”? (2000 years are needed to generate 10 cm of topsoil.)
• What are the consequences of soil degradation? (We can’t benefit from the many ecosystem services that healthy soil provides, degraded soil makes us vulnerable. Climate change
is also worsened because degraded soil can store less CO2. For example, Niger loses 8% of
its GDP because of excessive grazing and salinity of soils in rice fields. There are also environmental and humanitarian disasters caused by degraded soil – dust storms, water shortages and yield shortages – which can lead to famine, forced migration and conflict.)
• How can the problem be prevented? (We need to start calculating the true costs of our inaction – we need to include the value of ecosystem services provided by healthy soils and
the cost of degraded soils in our calculations. Use sustainable land management practices.
Use a system thinking approach and take into account the views of all stakeholder groups.)
Collect several answers from volunteers.
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Soil degradation
We suggest that you organize this one practical activity (a scientific experiment) because it will illustrate in practice how soil erosion is enforced on bare soils and is prevented on soils covered with
vegetation.
To set up the activity you will need to do some preliminary preparation and obtain the necessary
materials. Please, follow the steps which are very clearly shown in the video. Bring the prepared
materials to the classroom and conduct the experiment in front of the students. You can have 1
person come in as a volunteer to water the three types of soil.
(15 min.)
CORE
4. PRACTICAL ACTIVITY
“Erosion and Soil”: https://www.youtube.com/watch?v=im4HVXMGI68 (7:35 min.). Use this video
only for your personal preparation. Do not play the video in class.
After the experiment is done ask the following questions to the students and initiate a discussion:
• Was there any difference between the water coming out of each of the three plastic pots
into the plastic collectors? What was the difference? Which was the cleanest water?
• Why was the soil that had plants on it capable of preventing soil flow out into the container
together with the water? (You can take out the soil in the third plastic bottle together with
the vegetation to illustrate how it stays together.)
• What do you think this means for agricultural systems? How should agriculture look like if
soil erosion is to be prevented?
5. CASE STUDIES
You can choose among the case studies below and present one of them to the class. You can also
divide the class into groups and assign a different case study to each group. Let each group report
to the others after they complete their research.
1) Option 1: Slow Food vs. Fast Food
Ask the students if they have heard of Slow Food and if they know what it is. Tell them that Slow
Food is an international movement which began in Italy in 1986. Slow Food’s mission is to prevent
the disappearance of local food cultures and traditions, counteract the rise of fast life (Slow Food is
the opposite of Fast Food) and combat people’s decreasing interest in the food they eat, where it
comes from and how our food choices affect the world around us. Slow Food believes that through
our food choices we can collectively influence how food is cultivated, produced and distributed,
and as a result bring about great change.
Let the students explore the Slow Food website http://www.slowfood.com/ and find answers and
form an opinion on the following questions:
• What are the principles of Slow Food? (http://www.slowfood.com/about-us/our-philosophy/)
• How important do you think small farmers and peasants for the global food production
system are?
• Which do you think is better for the soils and for us as food consumers – farms where only
one crop is grown on huge fields or farms where a variety of crops are grown?
• Do you know of places in your community where you can get access to food that was produced in keeping with the Slow Food principles? (Students can even search for a while on
the Internet and try to locate such grocery shops, farmers markets or restaurants.)
Collect several answers to the questions.
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(12 min.)
OPTIONAL
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2) Option 2: Greening the desert through intelligent design and permaculture
Ask the students if they have ever heard of permaculture - a philosophy of working with, rather
than against nature, a system of agricultural design principles centered on simulating or directly
utilizing the patterns and features observed in natural ecosystems. Tell the students that they are
now going to watch a video featuring one of the leading world experts and practitioners of permaculture design – Geoff Lawton from Australia, a person who has been credited with turning deserts
and dry areas into productive food systems around the world.
Ask the students to pay attention to the following questions and collect several answers after you
play the video:
“Permaculture Principles in Application ‒ Geoff Lawton”: https://www.youtube.com/watch?v=N225HDyIUe8 (5:15 min.).
• What enabled Geoff’s farm to have a lot of water in the middle of the worst draught experienced in his area?
• At some point Geoff says “If you could live with this little bit of disorder in appearance, we
can live on this Earth forever and in a system we can be proud of”. Do you think his farm
looks disorderly?
• How is this system different from the way large-scale farming and agriculture is done nowadays?
• How much effort does it require to create a self-sustaining system like that?
• What can be the benefits of adopting the permaculture methods?
6. ENTREPRENEUR PROFILES
(12 min.)
OPTIONAL
You will find below several profiles of big and small companies that are striving to employ agricultural practices that regenerate soil rather than deplete it. You can divide the class into four groups
and assign each company to a different group to explore. Let them have the following questions in
mind when exploring and have each group make a short report after the end of their research (they
should appoint a spokesperson):
• What is the business idea?
• What problem is the company trying to solve?
• What is the guiding philosophy/principle of the company?
• Why would you buy a product from this company?
1) Neptune’s Harvest: http://www.neptunesharvest.com/. This is a company which produces
organic, non-chemical fertilizers out of valuable fish by-products.
2) Unilever: https://www.unilever.com/, https://www.unilever.com/sustainable-living/ and
https://www.unilever.com/sustainable-living/the-sustainable-living-plan/reducing-environmental-impact/sustainable-sourcing/our-approach-to-sustainable-sourcing/our-sustainable-agriculture-programme.html. This is a huge company, the world’s third largest
consumer products company – producer of about 400 different brands, ranging from soaps,
shampoos and detergents to ice creams. It is one of the most impressive cases of a transformation of a large company toward genuine sustainability through measurable steps to reduce its environmental impact and improve the livelihoods of small producers that depend
on it for their income.
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Soil degradation
3) Polyface Farm Inc.: http://www.polyfacefarms.com/. Polyface, Inc. is a family owned,
multi-generational, pasture-based, beyond organic, local-market farm and informational
outreach in Virginia’s Shenandoah Valley. The main products are: eggs, pork meat, turkey
meat, beef, etc.
4) Grove Garden: https://grovegrown.com/. An innovative, in-home garden inspired by nature
to help you grow your own fresh, delicious food year round.
You can ask the following questions to the whole class and collect several answers from volunteers.
Alternatively you could ask the students to fill in their answers individually in written form in the
worksheet provided:
• Is soil a renewable or non-renewable source, in your opinion?
• Is it possible to feed a growing population of about 9 billion people and maintain sustainable agricultural practices at the same time?
• Knowing about the dangers associated with industrialized large-scale agriculture, how likely are you to change your choices as a food consumer?
(5 min.)
CORE
7. REFLECTION
8. A LOOK INTO THE FUTURE
Tell the students that next time they will start a new chapter in the GREENT course where they will
gradually start learning a lot about sustainable development as a framework, way of thinking and
way of doing things that can contribute to finding the right balance that can secure a flourishing
future both for the environment and the human societies.
CORE
9. HOMEWORK
Choose one of the options for homework below and explain it to your students:
• Tell your students that for homework they will need to go online and take the sustainable
food quiz available here: http://environment.nationalgeographic.com/environment/greenguide/quizzes/sustainable-food/, as well as the green seasonal food quiz: http://environment.nationalgeographic.com/environment/green-guide/quizzes/seasonal-food/.
After
answering each question they will receive valuable information that will help them make
more informed and sustainable choices about the food they buy and eat, supporting farmers that care about the health of their land and animals.
• Play the online game “Third world farmer”. The game lets you experience some of the hardships of farming in a poor country. Will you prosper despite corruption and lack of basic
necessities? Or will endless wars, diseases, droughts, and unreliable markets perpetuate
your economic disadvantage and spell your ultimate doom? “3rd World farmer” is a serious
game, developed on a very slim budget by students from Denmark. It is not precise in all
details, but covers a wide range of topics. It is meant to be both educational and slightly
provocative, with the sole intent of making people think about these topics and, hopefully,
realize that each of us can make a difference in helping to end poverty. To play: http://3rdworldfarmer.com/.
• Explore the website FoodMyths: http://foodmyths.org/. This is a project of Anna Lappe.
It was born out of the need for a project that could spread the real story of our food, debunking persistent myths about sustainable food and farming, through compelling media,
a new online information center, and grassroots events. Each of the mythbusting movies is
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Lesson 11
grounded in the best science and research out there, so be sure to check out the companion
reading guide and annotated transcript—with citations and sources for every assertion you
hear. You can even encourage your students to invite Anna to deliver a webinar for the class.
They can use the online form here and send a request to her: http://foodmyths.wpengine.
com/host-an-event/.
10. ADDITIONAL LINKS
These are additional resources that you as a teacher can use in order to prepare for the lesson
broadening your knowledge. You can also use these resources by assigning them to the students
as out-of-class reading/viewing.
• A video lesson on “Soil Conservation: Fighting Soil Erosion With Sustainable Soil Use”:
http://study.com/academy/lesson/soil-conservation-fighting-soil-erosion-with-sustainable-soil-use.html#transcriptHeader. A written transcript and a quiz are also available. Requires free registration to unlock the full content.
• “How to green the world’s deserts and reverse climate change | Allan Savory”: https://
www.youtube.com/watch?v=vpTHi7O66pI. “Desertification is a fancy word for land that
is turning to desert,” begins Allan Savory in this quietly powerful talk. And terrifyingly, it’s
happening to about two-thirds of the world’s grasslands, accelerating climate change and
causing traditional grazing societies to descend into social chaos. Savory has devoted his
life to stopping it. He now believes -- and his work so far shows -- that a surprising factor
can protect grasslands and even reclaim degraded land that was once desert.
• “Key Differences Between Organic & Sustainable Food”: https://www.thebalance.com/
difference-organic-sustainable-food-2538316. Although often used interchangeably, organic and sustainable are not the same.
• “Committing to sustainability with Unilever CEO Paul Polman”: https://www.youtube.
com/watch?v=nShlnBJko5s (4:03 min.). “The amount of resources we currently use is 1.5
times the world’s resource capacity. Is that sustainable? A billion people still go to bed
hungry. Is that sustainable? The richest 85 people have the same wealth as the bottom 3.5
billion. Is that sustainable?” In this interview with McKinsey’s Rik Kirkland, Paul Polman
discusses why capitalism must evolve, his company’s efforts to change, and how business
leaders are critical to solving intractable problems.
• “Unilever - not as clean as it claims”: https://www.youtube.com/watch?v=33Theeovq1c
(3:24 min.). Unilever, one of the world’s most successful and profitable companies, is
trying to change the existing workers’ pension scheme to one that will see thousands of
workers retire on a pension reduced by up to 40%. Workers have been fighting to save
their pensions, they held the first ever national strike at Unilever in December and are
continuing with further strikes across the UK this week.
• “Attention Food Lovers: Eco-Conscious Eating Isn’t All About Distance”: https://www.
nrdc.org/stories/attention-food-lovers-eco-conscious-eating-isnt-all-about-distance. Want
to make a real difference with your grocery money? Find out where and how your food is
produced.
• “Food Matters: Pesticides”: https://www.nrdc.org/stories/food-matters-pesticides. How
these toxic chemicals can do more harm than good.
• “Industrial Vs Sustainable Agriculture”: https://www.youtube.com/watch?v=7TRI7yeeYQQ (6:29 min.). Sustainable farms protect the soil and the health of farm workers and consumers much better than the industrial farm. But can it feed all the people in the world?
Research after research shows that this is possible. And we as consumers can help this
product with our choices about what we eat.
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Worksheet
Soil degradation
Lesson 11
Is soil a renewable or non-renewable source, in your opinion?
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
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Is it possible to feed a growing population of about 9 billion people and maintain
sustainable agricultural practices at the same time?
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
Knowing about the dangers associated with industrialized large-scale agriculture,
how likely are you to change your choices as a food consumer?
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________