Reality → Life → Biochem → Elements
Hydrogen, oxygen, and carbon are the three key elements of life. In the human body, these elements account for 93 % of mass and 98 % of the number of atoms [1] . Other relatively frequent elements are nitrogen, calcium, and phosphorous, making up 5.5 % of the average person’s mass, while all other elements account for only 1.5 %. The bulk of our food is ultimately based on cultivated crops, which absorb carbon from air, hydrogen and oxygen from water, and basically all other elements from soil whose productivity has been greatly increased by the application of synthetic fertilizers [2] . The three most important fertilizer elements are nitrogen, phosphorous, and potassium. Nitrogen, an essential component of proteins, is the most important element to promote fast plant growth and high crop yields. Phosphorous is a key element in photosynthesis. Potassium is an essential element of many enzymes that catalyze metabolic processes. Other important elements of industrial fertilizers are calcium, magnesium, and sulfur. Calcium promotes root growth and is needed for compounds that build cell walls. Magnesium is a key element of chlorophyll. Sulfur, like nitrogen an essential component of proteins, is also involved in the formation of chlorophyll. Biologically important trace elements often enter the food chain through fertilizers. They include Iron, boron, zinc, manganese, molybdenum, copper, and chlorine.
Synthetic fertilizers, along with mechanization, improved irrigation, and use of pesticides/herbicides, led to the ‘green revolution‘ that supported an explosive growth of global population during the 20th century. Possibly the most important base of this revolution was the development of industrial ammonia synthesis, the catalytic combination of nitrogen and hydrogen (first industrial production in 1913 at BASF, Nobel prizes in 1918, in 1931, and even in 2007). The synthesized ammonia is processed into urea and ammonium nitrate, two common nitrogen-based fertilizers. Phosphorous-based fertilizers (superphosphates, ammonium phosphates) are produced by a process that recovers phosphoric acid from mined phosphate rock with sulfuric acid. Potassium-based fertilizer (sylvite) is recovered from mined potash, a mixture of potassium salts. The three fertilizer elements are often combined at varying ratios in NPK-fertilizers.