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 nutrients a plant may be lacking. Many plants engage in symbiosis with microorganisms. Two important types of these relationship are Though nitrogen is plentiful in the Earth's atmosphere, relatively few plants harbour nitrogen-fixing bacteria, so most plants rely on nitrogen compounds present in the soil to support their growth. These can be supplied by mineralization of soil organic matter or added plant residues, nitrogen fixing bacteria, animal waste, through the breaking of triple bonded N molecules by lightning strikes or through the application of fertilizers. At least 17 elements are known to be essential nutrients for plants. In relatively large