Chapter 1 The cycling of Nitrogen and Sulphur in Ecosystems Chapter 2 Acidity Chapter 3 The Energetics of Life Processes Chapter 4 Biochemistry of Nitrogen Utilization Chapter 5 Biochemistry of Sulphur Utilization Chapter 6 The Regulation of Cell pH Chapter 7 Ionic Imbalances in Plans Chapter 8 Acid Soil Chapter 9 Impacts of Acid Soils Chapter 10 Acid rain Chapter 11 Impacts of Acid Rain Chapter 12 Estimation of Rates of Acidification Chapter 13 Neutralizing the Impacts of Acidification Appendix 1 Calculation of Work Potential and rH