The Environment - Soil Degradation (Lesson 1)

THEME : LIVING THINGS, LIFE PROCESSES AND THE ENVIRONMENT 

FOCUS QUESTION

How do environmental problems affect us?

SPECIFIC OBJS.

1.  Describe the factors that cause soil degradation

2.  Show concern for the impact of environmental problems on humans.

3. Be aware of their responsibility to carry out good environmental practices

CONTENT SUMMARY

Soil is a valuable resource. We need soil so that we can grow crops for our food and to feed animals. The plants that grow in soil can help[ reduce carbon dioxide in the atmosphere and protect us from high winds and waves. Many animals need soil in order to survive. Soil can easily be spoiled and this is called degradation. Soil that is damaged can easily be blown or washed away. This is called erosion.

Some causes of soil degradation include slash and burn, soil exhaustion, climate change, soil erosion, deforestation, chemical fertilizer and pesticide use.

There are many ways to solve the problem of soil degradation. These include terracing, drainage system,, contour farming, alternate crop rotation, agro-forestry, using compost from animals and plants as fertilizer.         

ENGAGE

Listen to a song which speaks of soil degradation (youtube video-“Soil degradation song), then discuss what message the song is conveying. Teacher led discussion will follow to generate a meaning for soil degradation.

Examine different soils depicted  below and describe their  appearance.

Will things planted come to maturity on these soil? 

How did all this happen?

 

EXPLORE

Watch this video entitled “Soil Degradation 2” to glean information on what soil degradation is, how it happens, and how humans contribute to it. As you listen, try to glean information to populate the table below.

WHAT IS SOIL DEGRADATION?
CAUSES OF SOIL DEGRADATION
EFFECTS OF SOIL DEGRADATION
COMBATTING /PREVENTING SOIL DEGRADATION

EXPLAIN

In groups, present the information gleaned in a form/media of your choice, ensuring that you state definition and the different causes of soil degradation.

EXTEND/ELABORATE

Students will use materials presented to do further research on the following: soil erosion, deforestation, slash and burn, soil exhaustion, chemical fertilizer and pesticide use as contributing factors to soil degradation. Classify them as human factors and natural factors.

EVALUATE

1.       Use the words below to fill the blank spaces. Use each word only once.

Human     ,     soil erosion    ,     quantity       , overgrazing ,      deforestation,

The decline of soil _____ or quality is referred to as soil degradation. Some ___ activities like _________ can contribute to soil degradation. ____ is also another factor that can cause soil degradation.

 

2. 

The following are factors contributing to soil degradation. Briefly explain what each is and how it can be solved.

 

(a)    Soil erosion: ____________________________________________________________________________________________________________________________________________________

                   Solution:                                                   ______________________________________________________________________

         ______________________________________________________________________________

(b)   Soil exhaustion: ______________________________________________________________________________________________________________________________________________________

Solution:_______________________________________________________________________________________________________________________________________________

(c)    Chemical fertilizer and pesticide use: ____________________________________________________________________________________________________________________________________________________Solution: __________________________________________________________________

1.       Examine the diagram below carefully. After analyzing, use it to determine if it supports or not support  the statements in the table that follows. Simply place a [ü] if it supports or not.

      

STATEMENTS	Supported by diagram	Not supported  by diagram
Rain is a human factor that causes erosion
Grazing livestock is a human factor that contributes to erosion.
Humans contribute to soil erosion
If it were not for humans, soil erosion would not exist.