RIC-3531 Primary Science - Book D (Digital)

Changes to the Local Environment
Changes in the Local Environment – Activity 4
Lesson Focus
Outcomes
Earth and Beyond
2.2 Describes changes
that occur in the local
environment.
Indicators
• Reads and analyses
information about land
clearing and the effects it
has on farming.
• Evaluates an area of soil
that is degrading. Devises
a plan to improve the
condition of the soil.
Skills Focus
• Compares
• Analyses
• Conducts investigation
Background Information
Clearing the land has caused
a number of problems. When
trees and plants are cleared
for farming, the soil begins
to erode from wind and rain.
Plants help to keep the soil
in good condition with their
roots, allowing oxygen to
move through the soil. The
roots of the trees and plants
help to keep the soil together
and prevent it from being
blown away.
Because of land-clearing and
destructive farming methods,
the Earth now has large areas
of soil that are useless to the
environment.
Some farmers cause problems
for soil conservation by
overgrazing their land. This
occurs when too many animals
graze on too small an area
of land. All of the grass and
shrubs are eaten, leaving the
soil loose and easily blown
away by water and wind or
carried away by water.
Before the Lesson
Materials Needed
Pictures of farming equipment used at the turn of the century and the machines
used today. An area of the school grounds where the soil is in poor condition.
Preparation
• Walk around the school and find areas in the school grounds where the soil
appears to be in poor condition. These areas may be where students walk or play,
or near a tap or water fountain.
The Lesson
Stimulus
• Show the students a loaf of bread. Ask them where it comes from. Talk to them
about wheat and the process of farming it. This includes ploughing, seeding,
fertilizing and finally harvesting. Explain that to grow crops such as wheat, the
condition of the soil must be good. Ask the class what might make the soil poor.
Make a list.
What to Do
• Read the passage about farming. Show the students the pictures and photographs
of the farming machinery. Compare them. Ask the students what the main
differences would be when using them. Talk about time and how important it is
during harvest for the crops to be collected before the wet season. (This is due to
the wheat swelling and barley becoming stained.)
• Students compete Question 1 (a) of the blackline; 1 (b) may need pair, group or
class discussions to be completed. Discuss overgrazing with the students as another
cause of soil degradation.
• Explain to the students that they are going to be studying an area in the school
grounds where the soil is in poor condition.
• Walk around the grounds and find an area or areas that the students can study in
small groups. Students complete Question 2 of the blackline.
• Posters are designed and displayed to make the school aware of the degraded soil.
Each week, the soil can be checked by students, who report back to the class on its
condition. Through the effort of the class, the areas should start improving.
After the Lesson
Answers
1. (a) Teacher check
(b) Plant trees and native vegetation to improve the quality of the soil. Make sure
they don’t overgraze the land by moving the sheep or cows from paddock to
paddock and limiting stock numbers.
2. Answers will vary.
Additional Activities
• Study other areas in the school grounds with soil degradation. Have different
groups looking after the areas. Make weekly reports on any changes. Compare
each site and discuss the cause and possible solution to the damage.
• Research the farming methods at the turn of the century. Present the information
as a poster with facts, diagrams and a time line.
Display Ideas
• Display the pictures and photographs of past and present farming machinery with
explanations of the difference and the progression.
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38 PRIMARY SCIENCE ~ R.I.C. Publications ® ~ www.ricpublications.com.au
ISBN 978-1-925660-54-8