Eutrophication Eutrophication means growth in plant primary production. Eutrophication happens both in water and on land, land ecosystem eutrophication manifesting itself in increased forest growth and changes in vegetation. Forest growth accelerated in the last century as a result of increased nitrogen precipitation and higher levels of carbon dioxide in the atmosphere. In waterways, eutrophication causes cloudiness, an increase in aquatic plant life, excessive growth in phytoplankton and filamentous algae, and a dearth or absence of oxygen on the bottom.
Eutrophication changes the species composition, usually also causing a reduction in species numbers.
This can also have a negative impact on human and animal health, and on recreational use of waterways. Eutrophication also impedes fishing and prevents industrial or domestic use of the water. The most important water eutrophicants are phosphorous and nitrogen. Most of the phosphorous comes from scattered agricultural and domestic sources. Nitrogen emissions are mostly from agriculture and traffic.