LUPANE STATE UNIVERSITY
Faculty of Agricultural Sciences
DEPARTMENT OF CROP AND SOIL SCIENCES
ASSS1203 Introduction to Soil Science
Course Synopsis
The course covers the history of soil science and concepts of a soil, and is a general
introduction to soil formation, soil classification, soil conservation, soil survey, study of
soil forming factors (climate, organisms, parent material, relief, and time), processes of
soil formation and soil profile morphology. Students are also introduced to mineralogy of
soils, chemical and physical properties of soils, soil water relationships, soil temperature,
soil organic matter, and plant nutrition and soil fertility. Human activities and their effect
on soil quality are also covered.
Course Structure
Lectures: 30 hours (One 2.5 hr session per week)
Practicals: 18 hours (One 3 hr session per fortnight)
Lecturer and Course Coordinator: Melusi Moyo email: memoyo@lsu.ac.zw,
melusim5@gmail.com cell: 0772 249259
Course Objectives
The course is intended to provide students with a comprehensive introduction to the field
of soil science. Students are expected to gain an understanding of the basic properties of
soils, their interrelationship, and how soils function as a dynamic system. A secondary
objective of this course is to help students to use this basic understanding of soils to
develop their problem solving abilities.
At the end of the course, students should:
1. Know the basic terms used for the description, study and management of soils.
2. Understand soil chemical and physical properties and processes important to
agriculture and non-agricultural soil uses.
3. Develop skills in determining soil properties and interpreting soils information
necessary for the productive use of soils.
4. Be able to apply knowledge of soils in maintaining and improving environmental
quality.
Course assessment
40% of the final course mark will come from continuous assessment comprising
a) Tests and quizzes
[50 %]
b) Laboratory practicals
[25 %]
c) Field practical (catena)
[25%]
60% of the final course mark will come from the final examination mark.
The final examination may include material covered under continuous assessment.
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Course outline (Lectures)
WEEK
TOPIC
1
INTRODUCTION
Functions of soils in the ecosystem.
PHYSICAL PROPERTIES OF SOILS
Soil morphology-colour; texture; structure; consistence.
2
Density; porosity; permeability and drainage.
Soil temperature
3
Soil horizons and profiles
SOIL FORMATION
Weathering of rocks and minerals; physical weathering; biochemical weathering.
4
Factors of soil formation-parent materials, climate and biota
relief (catena concept) and time
5
Processes of soil formation (R.W. Simonson’s model).
COLLOIDAL PROPERTIES OF SOILS
Properties and types of soil colloids,
6
Layer silicate clay structure, mineralogical organisation of silicate clays.
Structure of non-silicate colloids.
7 & 8 Midsemester break
9
Sources of charges; permanent and variable charges.
CHEMICAL PROPERTIES OF SOILS
Adsorption of ions, cation exchange capacity (CEC); anion exchange, total
exchangeable bases (TEB); base saturation (BS); exchangeable sodium percentage
(ESP); EC and SC values.
10
Soil sodicity and salinity
Acidification process, role of aluminium in soil acidity (speciation)
11
SOIL ORGANIC MATTER
Carbon cycle; decomposition and mineralization; organic matter and soil properties;
C/N ratio
SOIL ORGANISMS AND ECOLOGY OF THE SOIL
Soil organisms-their role in the soil system (mineralization, BNF)
12
SOIL WATER
Soil water content(available water, saturation, field capacity, permanent wilting
point) and flow (infiltration and percolation)
13
Irrigation concepts, moisture retention.
SOIL CLASSIFICATION AND MAPPING
Concepts of individual soil and overview of soil classification. The Zimbabwean Soil
Classification System -orders, groups and families
14
The Zimbabwean Soil Classification System-series.
Major soils of Zimbabwe- their use, constraints and management
2
Practical schedule
Date
Practical/Activity
Soil colour and texture (by feel) - lab
Parent materials
Particle size distribution -hydrometer method - lab
Pit description – local field trip
Examine a Catena – Field trip
Soil bulk density, particle density, moisture content - lab
FINAL EXAMINATIONS
Recommended Text
1. Brady, N.C. & R.R. Weil. 2002. The Nature and Properties of Soils. 13th Ed. Prentice
Hall Publishing Co. New York, USA. (Check with the lecturer for overnight access to
this book)
2. Foth, H.D. 1990. Fundamentals of Soil Science. 8th Ed. John Wiley and Sons New York,
USA. (available at LSU library)
3. Thompson J.G. and W. D. Purves. 1981. A Guide to the Soils of Zimbabwe. Zimbabwe
Agricultural Journal Technical Handbook No. 3 (check with lecturer for a copy of this
book)
4. Nyamapfene, K.W. 1991. Soils of Zimbabwe. Nehanda Press, Harare, Zimbabwe.(two
copies available at LSU library)
5. Bennet, J.G. 1985. A Field Guide to Soil and Site Description in Zimbabwe. Zimbabwe
Agricultural Journal Technical Handbook No. 6 (check with lecturer for a copy of this
book)
6. Fitzpatrick, E.A. 1986. Soils: their formation, classification and distribution. Longman,
UK. (available at LSU library)
7. Schaetzl, R and S. Anderson.2014. Soils: Genesis and Geomorphology. Cambridge Press.
6th edition. (available at LSU library)
8. Buol, S.W. et al.2003. Soil genesis and classification. Iowa State Press, Iowa, USA.
(available at LSU library)
9. SoilTrEC book on soil for secondary school, 12 factsheets,
Publications
http://eusoils.jrc.ec.europa.eu/projects/Soiltrec/Outputs.html
10. Krzic M., T. Naugler, S. Dyanatkar, and C. Crowley. 2010. Virtual Soil Lab Modules.
The University of British Columbia, Vancouver. [http://labmodules.soilweb.ca/]
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