Nutrients are chemical elements that all plants and animals require for growth. On the earth, there is a constant and natural cycle how these elements are incorporated when an organism grows, and degraded if an organism dies. The nutrients used in the largest amounts are the non-mineral elements, i.e. carbon (C), hydrogen (H) and oxygen (O). These elements are mainly taken up as carbon dioxide (CO2) from the air, and water (H2O) by the roots (JOENSSON et al. 2004). They make up 95-98% of the mass of all living beings (MAHENDRAPPA 2007). But they are, however, not sufficient for life to exist. Further elements are important to fuel life on earth: Nitrogen (N) and Phosphorus (P), Potassium (K) as well as Calcium (Ca) and Magnesium (Mg) are highly important, in particular for plant growth and agriculture. These elements are often referred to as macro nutrients. Their uptake is about 100 times that of micro nutrients. Further nutrients, that plants take up in a much smaller amount and that are essentially consumed by humans, include Boron (Bh), Copper (Cu), Iron (Fe), Chloride (Cl), Manganese (Mn), Molybdenum (Mo) and Zinc (Zn) and others. These are called micro nutrients (JOENSSON et al. 2004).
Submitted by admin on Mon, 12/04/2017 - 08:01