Topic 2: The Protection of Soils


Once established, soils remain dynamic systems that are always at risk of some form of erosion. This may occur naturally, but often is related to anthropogenic activities. The initiation of erosion is often related to some form of disturbance, with the removal of the vegetation cover being by far the most significant. Erosion is greatest where there is the greatest amount of energy, which in the context of soil erosion is on slopes.

In this module, we will first look at some of the processes occurring on slopes and how these interact with anthropogenic activities. The movement of rock materials and soil downslope is known as mass wasting, and is very important for forestry. The material may accumulate at the base of the slope, or may enter the fluvial system and be removed by streams and rivers. In some cases, the slope system and the fluvial system are coupled – material may be eroded from a gully wall on the upper part of a steep slope, directly entering the fluvial system, or a landslide or debris flow may transport debris directly into a stream channel.

We will also examine the processes that lead to soil degradation. These vary from one forest area to another, but in some parts of the world are very important. Forestry activities may be particularly important, and can actually lead to some of the erosion processes found in the slope and fluvial systems. On the other hand, forestry activities can also help conserve soil and can help stabilize areas that are unstable for a number of different reasons (such as eroding slopes or moving sand dunes).

Video Lectures

3.2.1 Mass movements

3.2.2 Soil degradation

3.2.3 Reducing soil degradation

3.2.4 Desertification 1: Dryland forests and desertification

3.2.5 Desertification 2: Causes of desertification

3.2.6 Desertification 3: China’s response


Textbook Reading:

  • Chapter 6 of the course text:
    Innes, J., & Tikina, A. (Eds.). (2014). Sustainable forest management: From principles to practice. London: Earthscan Publications. ISBN: 1844077241

Further Reading:

Other sources:


Module III - Topic 2: Self-test

Quiz Description:

The following self-test quiz is designed to check your understanding of important learning concepts for this topic. The quiz contains ten multiple choice questions. There is no time limit for you to take the quiz and you may attempt to take it as many times as you like. After you click the Submit button, you will see your Grade, number of Correct Answers, your answers, and the Answer Key for each question.

Quiz Instructions:

While you are taking the quiz, we advise you not referring to any course materials. After you Submit your answers, you may self-reflect the missing points, review relevant contents as necessary, and retake the quiz again until you get the full points

Answer the following questions to see how well you have learnt in this topic: