Level: Master’s
Institution: Ardakan University
Faculty: Agriculture & Natural Resources
Role: Course instructor (lectures + field/lab)

Overview

This course provides an advanced foundation in soil genesis (pedogenesis) and soil classification, focusing on how soils form, differentiate, and can be systematically described and classified for scientific and applied purposes. Students learn the major concepts and processes controlling soil development, then apply this knowledge through two widely used classification frameworks: WRB (World Reference Base for Soil Resources) and USDA Soil Taxonomy.

A central part of the course is hands-on field and laboratory work, where students describe soil profiles using standard terminology, interpret diagnostic features, and perform soil classification based on observable properties and supporting measurements.

Learning objectives

By the end of this course, students will be able to:

• explain major soil-forming factors and processes and how they shape soil profiles
• interpret pedogenic processes such as eluviation–illuviation, calcification, salinization, gleying, and horizon differentiation
• identify and describe key diagnostic horizons, properties, and materials
• conduct structured soil profile description in the field using standard methods
• classify soils using:
  • WRB (Reference Soil Groups and qualifiers)
  • USDA Soil Taxonomy (orders → suborders → great groups/subgroups; introductory-to-intermediate depth)
• justify classification decisions using evidence from morphology, site conditions, and analytical results
• communicate soil information effectively through profile logs, classification reports, and map-relevant descriptions

Teaching format

1) Theoretical sessions

Topics include:

• pedogenesis: state factors, energy and material fluxes, profile evolution
• soil horizons and morphological indicators of soil-forming processes
• diagnostic concepts: horizons, properties, and materials used in classification
• overview and logic of soil classification systems:
  • principles and structure of WRB
  • principles and structure of USDA Soil Taxonomy
• interpretation and applications: land evaluation, soil mapping, and management implications

2) Field & lab practicals

Students gain practical competence through:

• site characterization (landscape position, parent material, vegetation/land use, drainage)
• excavation and documentation of soil profiles
• soil profile description (horizons, color, structure, consistence, roots/pores, redox features, carbonates/gypsum where relevant)
• sampling strategy for classification-supporting measurements
• step-by-step classification exercises using WRB and USDA Soil Taxonomy
• preparation of a final profile description + classification report

Key topics

• Soil-forming factors and pedogenic pathways
• Horizon development and diagnostic features
• WRB: Reference Soil Groups and qualifiers
• USDA Soil Taxonomy: hierarchy and diagnostic criteria
• Field description standards and soil profile interpretation
• Linking classification to land use, management, and mapping

Assessment (typical)

• written exam or oral presentation (theory)
• field/lab performance and profile description accuracy
• classification assignments (WRB + USDA)
• final report: complete soil profile description, interpretation, and classification

If you are a student in this course and need access to field sheets, classification keys, or report templates, please contact me.