what is meaning of eutrophication ?????? What is d meaning of bioconcentration ???????

Eutrophication is the enrichment of an ecosystem with chemical nutrients, typically compounds containing nitrogen, phosphorus, or both. eutrophication can be a natural process in lakes, occurring as they age through geological time.
Bioconcentration is the process of accumulation of water-borne chemicals by fish and other aquatic animals through non-dietary routes