002 - Agricultural Activities

Geographic Knowledge and Understanding

Environmental consequences of agricultural activities on water quality, to include pollution (eutrophication) and irrigation (salinisation).


Agricultural practices impact natural processes and therefore impact the quality of water in range of places.


  • To be able to describe and explain the environmental consequences of agricultural activities on water quality.

  • To be able to describe and explain eutrophication.

  • To be able to describe and explain salinisation.

  • To be able to use detailed examples to show your understanding of the above.

Key Terminology

            • Nitrate chemicals

            • Algal bloom

            • Aquifers

            • Intensive agriculture

            • Agribusiness

Define the key terms above by using the 'Useful Links' below.

Useful Links

Activity One - Describe and Discuss

This syllabus point is specifically asking you to look at the impact that farming has on the water quality of a river. So to do this we need to look at the different types of farming practices and the types of nutrients and waste that those practices cause.

      1. Using a search engine, find a series of images that show what a feedlot is.

      2. In what ways can farming cause pollution? The class will be divided into teams to write an A6 guide (or podcast) on the impact that farming has on water. Use the diagrams below, and the article in the 'Useful Resources' box to help you.

                  • Cropping systems

                  • Livestock production

                  • Aquaculture

                  • Nutrients

                  • Pesticides

                  • Salts

                  • Sediments

                  • Organic matter

                  • Pathogens

                  • Emerging pollutants (antibiotics, vaccines, growth promoters, hormones, etc)

      3. How are the pollutants transported to the river?

Activity Two - Eutrophication

We are now going to look specifically at the first-named impact that agriculture has on water quality. You will need to know what it is, how it occurs along with the issues that it has created in a specific area. We are going to focus on Lake Erie, USA.

      1. Watch the youtube clip below and describe what eutrophication is and how it occurs.

      2. Using the 'Useful Resources' below describe and explain the impact that eutrophication has had on Lake Erie.

Activity Three - Salinisation

Many of you were fortunate to see the impact that salinisation was having on farmland in the village of Tinfou in Morocco. This was the hard white stuff on the soil that was generally caused by flood irrigation in Tinfou. Now salinisation may not seem to be a particular problem but when it is scaled it has a dramatic impact on the environment. We are going to focus on the Murray-Darling basin in Australia as our detailed example.

      1. What is salinisation?

      2. How does salinisation occur?

      3. What impact does salinisation have on the quality of the water?

Exam Style Question

Explain two ways in which agriculture and/or irrigation on flood plains can affect water quality. [3 + 3 marks] May 2014

This lesson was development in collaboration with Richard Allaway from geographyalltheway. For more resources please visit www.geographyalltheway.com