A Modified Waksman Procedure and its Applications to Soil Samples from Western Norway

Egil Alvsaker

Dr. philos. Thesis, Chemical Institute, University of Bergen, May 1949

Contents

Preface

Introduction

Description of the Soil Profiles

Various Lines of Organic-Chemical Humus Research

The Modified Waksman Procedure

Ether, Cold Water, and Alcohol Extraction

2 % HCl Extraction

Determination of Reducing Sugars

Determination of Furfural

Determination of Uronic Acids

12% HCl Extraction

72% H₂SO₄ Extraction

The Acid-Insoluble Humus Fraction

The Total Humus Content of the Soil

Ether-Water-Alcohol-Soluble Fraction

Acid-Soluble Fraction

Acid-Insoluble Fraction

Total Humus

Combined Water of Inorganic Origin

Description of the Analysis Method

The Distribution of the Humus in the Profile

The pH Values of the Profile Layers

The Chemical Composition of the Humus

Survey of the Humus Fraction Values

The Profile-Forming Processes

Decomposition Processes

The Ratio Between the Amount of Organic Matter Decomposed and Washed Down

Leaching Processes

Simplification of the Analysis System

General Summary

Literature

Tables

Figures