Soil is a fundamental resource for human life on our planet, Earth. More than 90% of the goods we need come directly or indirectly from the soil. However, it is under threat, dangerously eroded, its productive capacity severely tested, and we are witnessing a fall in food production, for which it is mainly involved. This drop in production is caused by the deterioration of the soil's characteristics, which constitute its fertility. At this turning point in history, with demographic growth accompanied by increasing food requirements, humanity faces the challenge of feeding all this population. It has become imperative for mankind to concern itself with the fate of the soil. The lives of all living beings, plants and animals, including humans, depend on this resource. Agricultural activity, which is nourishing, depends on the soil. It's up to the agronomist, the essential agent of agriculture, to better understand the soil in order to make better use of it. That's why this book, aimed at agronomy students, is so important and such a useful tool.