Eutrophication — Definition

Definition

Eutrophication is enrichment of a water body with nutrients that can stimulate excessive growth of algae and aquatic plants. Nitrogen and phosphorus are central to many such processes. The concern is not simply that algae exist: they are normal producers.

Excess growth can reduce light, increase organic material requiring decomposition and contribute to low dissolved oxygen. Human nutrient inputs can accelerate enrichment, although nutrient accumulation can also occur naturally.

Eutrophication should be distinguished from every form of water pollution, and an algal bloom should not automatically be described as toxic. The mechanism and the observed effects must be identified separately.