Sodium triphosphate (due to hydrolysis), no studies have been carried out to date concerning the chronic effects of STPP on these aquatic organisms. Predicted no-effect concentrations were therefore calculated for the aquatic environment and sediments on the basis of the acute aquatic ecotoxicity results. Detergents containing phosphorus contribute, together with other sources of phosphorus, to the eutrophication of many fresh waters. Eutrophication is an increase in chemical nutrients—typically compounds containing nitrogen or phosphorus—in an ecosystem. It may occur on land or in water. The term is, however, often used to mean the resultant increase in the ecosystem's primary productivity (excessive plant growth
Plant nutrition Plant nutrition Plant nutrition is the study of the chemical elements and compounds necessary for plant growth, plant metabolism and their external supply. In 1972, Emanuel Epstein defined two criteria for an element to be essential for plant growth: This is in accordance with Justus von Liebig's law of the minimum. The essential plant nutrients include carbon, oxygen and hydrogen which are absorbed from the air, whereas other nutrients including nitrogen are typically obtained from the soil (exceptions include some parasitic or carnivorous plants). There are seventeen most important nutrients for plants. Plants must obtain the following mineral nutrients from