Laboratory Manual for Soil Science: Agricultural and Environmental Principles (8Th Ed.)

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Laboratory Manual for Soil Science: Agricultural and Environmental Principles (8th ed.) by Stephen J. Thien and John G. Graveel, McGraw-Hill, 2003, 214 pages, spiralbound $54.38. This updated laboratory manual contains 15 exercises that investigate both agricultural and environmental aspects of nearly every fundamental physical, chemical, and biological soil characteristic. This edition follows earlier formats, but has not gone unimproved. The most unique feature of this particular manual may be the broad inclusion of multi-modal techniques for instruction of soil properties and soil management/conservation practices. Supported exercises use field tours/evaluations, movie viewing, physicochemical and biological laboratory procedures, and related resources for agricultural/environmental planning.

The first exercise introduces the systematic process of soil evaluation. Twenty-eight soil properties are listed by category, and further alphabetized for easy reference. Classification terminology and processes are defined, and implications to agricultural or other suitability are listed in well-organized formats. Whether using monoliths or soil pits, the straightforward 'Soil Profile and Site Evaluation Checklists' are likely to engage even the least enthusiastic undergraduate students. These tear-out worksheets list multiple-choices for soil biological, chemical, and physical properties of two horizons and provide an area to sketch the profile for later reference. Questions and tables prompt users for soil series or taxonomic classes and require appropriate soil surveys or access to the National Soil Survey Center's website (URL address is provided).

The following five exercises are devoted to instruction of soil physical properties and water relations. Exercises two, three, and four introduce the concepts of soil texture, particle size distribution (PSD), bulk density, and porosity. Lab procedures include the feel-method for soil textural class, the Bouyoucos and sieving methods for PSD, and the saran-coated clod and ring-sample methods for bulk density/porosity determination. Exercises five and six are concise guides to understanding soil water content and movement, respectively. Exercise five addresses effects of layering, horizon position, and texture on soil water content; and contains illustrations rivaling those found in modern textbooks. Exercise six is comprised of a video-observation activity; and capillary rise, pore column height, and soil aggregate-formation demonstrative procedures.

In Exercise seven, students are intimately introduced to the chemical processes of soil formation. Laboratory procedures illustrate effects of mineral weathering, hydrolysis, and biological soil carbonation and iron reduction. Though ominous at first read, the requisite procedures and methods are streamlined and repeatable.

In Exercises eight through 13, the manual continues its focus on soil chemistry. Exercise eight introduces fundamental mineralogy of clays, cation exchange capacity (CEC), and colloid physical behavior. Lab procedures employ mainly qualitative methods to illustrate cation adsorption, the lyotropic series, flocculation and dispersion of colloids, and shrinking and swelling tendencies of clay minerals. Exercise nine introduces active and reserve acidity of soils. Students use pH meters, displacing solutions, and a titration/neutralization reaction to quantify these properties. …