Key points are not available for this paper at this time.
Acknowledgements 2. Prologue 3. Soils in the Field Mineral Particles - the Soil Framework 4. Organic Materials - Alive and Dead 5. The Arrangement of Particles and Pores - Soil Structure 6. Water in Soils 7. Air in Soils - Supply and Demand 8. Particle Surfaces and Soil Solutions 9. Soil Acidity and Alkalinity 10. The Availability of Plant Nutrients - Potassium, Calcium and Magnesium 11. Phosphorous and Sulphur 12. Nitrogen in Soils 13. The Availability of Water in Soils 14. Soil Fertility 15. Salinity and Sodicity 16. Pesticides and Metals 17. Epilogue 18. Appendices 19. References
A 1994 study studied this question.