Plant nutrition of nutrient-rich water is pumped through the system to provide nutrients and water to the plant. 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).
Baltic Sea hypoxia lack of oxygen (anoxia) kills bottom-living organisms and creates dead zones. The rapid increase in hypoxia in coastal areas around the world is due to the excessive inputs of plant nutrients, such as nitrogen and phosphorus by human activities. The sources of these nutrients include agriculture, sewage, and atmospheric deposition of nitrogen containing compounds from the burning of fossil fuels. The nutrients stimulate the growth of algae causing problems with eutrophication. The algae sink to the bottom and use the oxygen when they decompose. If mixing of the bottom waters is slow, such that oxygen stocks are not renewed, hypoxia