Publisher's Synopsis
This book is intended as a reference for chemists and environmentalists who find that they need to analyze soil, interpret soil analysis, or develop analytical or instrumental analysis for soil. Soil scientists will also find it valuable when confronted by soil analyses that are not correct or appear to be incorrect or when an analysis does not work at all. There are two themes in this work: (1) that all soil is complex and (2) that all soil contains water. The complexity of soil cannot be overemphasized. It contains inorganic and organic atoms, ions, and molecules in the solid, liquid, and gaseous phases. All these phases are both in quasi-equilibrium with each other and constantly changing. This means that the analysis of soil is subject to complex interferences that are not commonly encountered in standard analytical problems. The overlap of emission or absorption bands in spectroscopic analysis is only one example of the types of interferences likely to be encountered.Soil is the most complicated of materials and is essential to life. It may be thought of as the loose material covering the dry surface of the earth, but it is much more than that. To become soil, this material must be acted on by the soil forming factors: time, biota, topography, climate, and parent material. These factors produce a series of horizons in the soil that make it distinct from simply ground-up rock. Simply observing a dark-colored surface layer overlying a reddish lower layer shows that changes in the original parent material have taken place. The many organisms growing in and on soil, including large, small, and microscopic plants, animals, and microorganisms also differentiate soil from ground-up rock. There are other less obvious physical changes constantly taking place in soil. Soil temperature changes dramatically from day to night, week to week, and season to season. Even in climates where the air temperature is relatively constant, soil temperatures can vary by 20 degrees or more from day to night. Moisture levels can change from saturation to air dry, which can be as low as 1% moisture on a dry-weight basis. These changes have dramatic effects on the chemical reactions in the soil. Changes in soil water content alter the concentration of soil constituents and thus also their reaction rates.
