Impact of nutrient enrichment in a waterchestnut ecosystem at Takahama-iri Bay of Lake Kasumigaura, Japan

Abstract

Active degradation of a waterchestnut was experimentally observed for several days after the death of the plant. During this process, more than 30% of the organic matter in the dead waterchestnut was releases as organic solutes and microbial particles into the ambient water. The remaining metabolizable organic components were also converted into microbial cells and remained inside the dead plant. Cellulose and other slowly decaying compounds in the plant residues were then sedimented onto the lake bottom and formed not only the primary energy source of detrital food chain in the ecosystem but also one of the major organic components of ooze on the lake bottom.