Premium
Limitation of water hyacinth by nitrogen in subtropical lakes of the Paraná floodplain (Argentina)
Author(s) -
Carignan Richard,
Neiff Juan José,
Planas Dolors
Publication year - 1994
Publication title -
limnology and oceanography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.7
H-Index - 197
eISSN - 1939-5590
pISSN - 0024-3590
DOI - 10.4319/lo.1994.39.2.0439
Subject(s) - hyacinth , floodplain , subtropics , environmental science , hydrology (agriculture) , ecology , biology , geology , paleontology , geotechnical engineering
Low (0.1–0.7 µ mol liter −1 ) dissolved inorganic nitrogen concentrations are common in the floodplain lakes of the Paraná River, where the water hyacinth ( Eichhornia crassipes ) is the major primary producer. We tested the hypothesis that N supply could limit production of E. crassipes during the growth season by adding NH 4 + or PO 4 3− during 1 month to large in situ enclosures. Those enclosures amended with N produced twice as much biomass as the controls and P‐treated enclosures. The low and limiting N content (1.3% AFDW) of the control and P‐treated plants provide a first diagnostic value for N deficiency in the field for E. crassipes . N limitation in these lakes may be attributable to high P supply from Andean rivers, high losses of macrophyte N during floods, and the unstable nature of floodplain lakes.