From Earth to Man: a Journey Into Rocks and Soils to Discover the Elements Useful for Life

The states of matter: solid, liquid, gas. Classification of matter based on composition: elements, compounds, mixtures. The periodic law and the periodic table of elements. Introduction to the topic of rocks; distinction between clasts - crystals; description of rocks of different nature; discussion on environments and formation processes. From atoms to molecules: the concept of chemical bonding. Representation of compounds: chemical formulas and molecular models. Non-bonding interactions: molecular recognition as a tool for building complex structures. Non-metals essential to life: C, N, O, S, and P fundamental for the construction of proteins, sugars, lipids, and nucleic acids. The functioning of the soil system in natural environments and the factors governing its development. Soil genesis through rock transformation and dynamics of organic matter in natural soils: processes and factors of pedogenesis, with particular emphasis on the biotic factor. How ongoing climate change influences the composition of soils and rocks, altering the availability of minerals, metals, and other elements. The impact of humans on the earth: ancient origins of a balance at stake today. Agronomic management of soils to meet crop needs, with particular reference to fertilization. What cultivated plants need: the need for cultivation techniques that allow these needs to be met. Management of cultivated soil: mention of soil tillage and fertilization. Fertilization to meet the needs of essential elements by crops. Mineral fertilizers. Brief mention of organic fertilizers. Starting from the six necessary elements present in the human body, we will move on to illustrate which other elements are indispensable for life, from the most abundant ones like calcium, potassium, magnesium, iron, and sodium, to those present in traces like copper, zinc, cobalt, nickel, and manganese. The origin and production processes of synthetic fertilizers: the nitrogen, phosphorus, and potassium cycle in nature and the role played by human intervention. The Haber-Bosch process for the production of synthetic nitrogen. Phosphate and potassium mineral deposits. Cartographic analysis of real earthquake, volcano, topography, and oceanic crust age data; distribution of useful/critical elements; accessibility and recharge. Distribution of useful elements in rocks and on the planet.