Principles of Soil Science

Colin Robins,
Claremont McKenna, Pitzer, and Scripps Colleges


Soils are complex features that reflect both past and present environmental conditions. This course is an intensive survey of the properties, genesis, and spatial distribution of soils, emphasizing key applications of soils data to ecology, environmental science, sustainable agriculture, land management, and climate change research.

Course Size:

Course Format:
Students enroll in one course that includes both lecture and lab. The lecture and the lab are both taught by the professor.

Institution Type:
Private four-year institution, primarily undergraduate

Course Context:

This is an upper division Environmental Science elective, with prerequisites of one year of introductory college-level chemistry (or accelerated equivalent) and one year of introductory college-level biology (or accelerated equivalent). Students taking this course will typically be majors in Environmental Analysis, Biology, Geology, or a related discipline.

Course Content:

This course, with laboratory, is an intensive introduction to the properties and genesis of soils, and to the expression of soils across landscapes past and present. Topics include soil morphology, soil physical and chemical properties, clay mineralogy, a survey of soil biology & ecology, effects of soil acidity and alkalinity, and the biogeochemical cycles of C, N, and other elements. Crucial applications of soils to environmental science, ecology, geology, agriculture, and/or archaeology, will also be addressed depending on student interests! Indoor laboratory activities entail physical, chemical and instrumental study of soil properties, while field sessions train students in the description, sampling,
and mapping of soils for a variety of research needs.

Course Goals:

  • Conduct a complete soil profile description using professional terminology
  • Demonstrate basic understanding of USDA NRCS soil orders
  • Learn where to find and how to apply existing soil science data resources & research to real world scientific challenges or land management issues
  • Explain the implications of specific soil properties for local Earth history, land use, or other purposes
  • Discuss, in detail, key global issues relevant to modern soil science (including carbon sequestration, paleoclimate analysis, soil salinization, soil erosion, and sustainable food production) and suggest avenues of targeted research that could improve our understanding of these topics.

Course Features:

Course goals are met through lecture, lab, discussions and written critiques of scientific papers, exams, and a capstone project. In the final, multi-week capstone project, students work in teams to address a soil science research question or soils-related environmental science problem, and present their results to their peers.

Course Philosophy:

This design provides students with a structured, safe, venue in which they are shown which topics or processes are most critical (class) and helped to discuss them. Real-world field experience forces students to apply the theoretical concepts they've learned to the characterization of naturally variable features and to the interpretation of carefully acquired chemical data. The capstone project is meant to help students use higher level thinking to apply their knowledge and training to real world problems of interest to them.


Assessment includes regular, quantitative and qualitative instructor feedback and successive, iterative development of critical thinking skills in laboratory and on critiques of scientific studies. Assessment also includes written examinations (for factual knowledge). Assessment of the final project is based on written and oral work, as well as on the improvement of the final project from an earlier, peer-reviewed draft.


Robins Soils Syllabus (Acrobat (PDF) 41kB Apr25 13)

Teaching Materials:

References and Notes:

Brady, N.C., & Weil, R.R., 2007. The Nature and Properties of Soils.
It is the most comprehensive, detailed text available, and is appropriate for both advanced and introductory students. Other texts were either incomplete, contained more errors, or were geared more specifically towards soil genesis or geography.

Students will read a range of papers from scientific journals - these vary year to year, and are chosen based on students' professed interests. Past topics have included carbon sequestration, urban soils, soil pollution, rare soils, and agroecology.