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Abstract
This lesson follows prior lessons that have focused on the
understanding of the interdependence of organisms. Extending those
understandings, this lesson directs students to investigate the
abiotic and biotic relationships in soil. Analysis of soil samples
from the student’s own yard will lead to an understanding of the
roles that nitrogen, potassium, and phosphorus play in the soil
environment. The teacher will discuss the "normal" level of these
elements found in the soil. A follow-up research assignment will
contrast those roles to potential hazards those chemicals pose in
the environment.
Lesson fundamental understandings:
Essential
Questions: A relationship exists between abiotic
and biotic factors in soil that humans, and other organisms, depend
on for survival.
Why is soil so important?
How do humans
impact the environmental balance in soil?
Standards
National Standards Life Science:
Interdependence of organisms Human beings live within the world's
ecosystems. Increasingly, humans modify ecosystems as a result of
population growth, technology, and consumption. Human destruction of
habitats through direct harvesting, pollution, atmospheric changes,
and other factors is threatening. Current global stability, and if
not addressed, ecosystems will be irreversibly affected. Technology
Standards: Technology research tools Information Literacy Standards:
Information literacy Social Responsibility
State Standards Florida: (SC.G.2.4.6)
The student knows the ways in which humans today are placing their
environment support systems at risk. Nebraska: (12.4.4) Investigate
and describe how humans modify the ecosystem as a result of
population growth, technology, and consumption.
Lesson
Prerequisite Skills
Understanding of biotic/abiotic classification;
understanding of the interdependence of organisms. The students
should also be familiar with the use of the dissecting microscope
and data collection techniques.
Teacher
Information/Situations/Setting/Time Time frame:
Three 45 minute periods
Materials:
Soil Analysis Lab
Soil test kits
Distilled water
Dissecting
microscopes/digital microscopes/video flex microscope
camera
Biology texts
Resources:
Rapitest kits
Soil Analysis Lab
http://molbio.nmsu.edu:81/hort100/organism.html
http://www.smartgardening.com/Soil_Organisms.htm
Pre-lesson
Preparation: From previous homework assignment, students should
bring a dirt sample from their own yard.
Assessment
Lab completion, class discussions, homework questions, and
research assignment allow the teacher to check for degree of
understanding.
Student Activity/Tasks Day One
1)
Engage students in this lesson with a class discussion regarding
soil: Generate a two-column list on board focusing on the uses of
soil and the organisms involved in those uses. Encourage students to
make the abiotic and biotic connections.
2) Using the samples
brought by the students, examine their soil under a dissecting
microscope (in groups of 3 or4). Instruct the students to identify
and draw as many organisms as possible. They may use their textbooks
or a Internet site for organism comparisons.
3) Using the text,
or a Internet site, students will list the roles each of their soil
organisms play in the production and maintainance of
soil.
Day Two
1) In groups of 3 or 4, the students will
test their soil samples using the Rapitest (or similar) kits (see
link under resources to found out about the Rapitest kit) , complete
the soil analysis lab. Students will answer questions (on lab) about
the roles of nitrogen, phosphorus, and potassium in soil while
waiting for test results.
2) Compile all results on a class data
table: Students should enter their results on this table as they
finish their lab.
3) Students should enter the class results on a
spreadsheet that they will print out to take home and analyze in the
following homework assignment:
a. What do the results tell you
about the soils? How different are they? Which ones have surpluses.
Which ones have deficiencies?
b. List some reasons that might
contribute to the surpluses or deficiencies in the soil
samples.
c. What have you learned about soils in this lab, that
helps you understand environmental issues that involve soil?
Day Three:
1) Class discussion regarding lab results:
Students will compare the surplus/deficiency results from their soil
samples. Ask students to share their hypotheses as to what could be
responsible for the differences.
2) Encourage students to
suggest solutions for the deficiencies. The discussion will likely
lead to the use of fertilizers. Discuss what is in fertilizers (ei.
N, K, & P.)
3) Research assignment: Using the Internet,
students will research the potential environmental hazards of N, K,
or P.
Enrichment/Alternate Activity:
1) Following the research assignment, students could write an
essay that focuses on the use of fertilizers in lawn care. They
should highlight the pros and cons of fertilizer use, then formulate
their own opinion about its use. 2) Students could organize a debate
that challenges the idea of governmental regulations of fertilizer
use.
Cross-Curricular:
Technology
Requirements/Tools/Materials
Internet access
Word processing program
Spreadsheet
software
Dissecting microscopes/digital microscopes/video flex
microscope camera
Acknowledgements:
Additional Resources
Main
URL:
Related Lessons
Related Resources
Copyright © 1997-2003
Career Connection to Teaching with Technology
USDOE Technology Innovation Challenge Grant
Marshall Ransom, Project Manager
All rights reserved.
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