A mass balance assessment of the contribution of floating-leaved macrophytes in nutrient stocks in an eutrophic macrophyte-dominated lake
Marion, L.; Paillisson, J.-M. (2003). A mass balance assessment of the contribution of floating-leaved macrophytes in nutrient stocks in an eutrophic macrophyte-dominated lake. Aquat. Bot. 75(3): 249-260. http://dx.doi.org/10.1016/s0304-3770(02)00177-8
In: Aquatic Botany. Elsevier Science: Tokyo; Oxford; New York; London; Amsterdam. ISSN 0304-3770; e-ISSN 1879-1522, more
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| Keywords |
Accumulation
Chemical elements > Nonmetals > Atmospheric gases > Nitrogen
Chemical elements > Nonmetals > Phosphorus
Cycles > Chemical cycles > Geochemical cycle > Biogeochemical cycle > Nutrient cycles
Nutrients (mineral)
Population characteristics > Biomass
Water > Shallow water
Water bodies > Inland waters > Lakes > Eutrophic lakes
Nymphaea alba; Nymphoides peltata; Trapa natans L. [WoRMS]
France, Pays de Loire, Grand-Lieu L. [Marine Regions]
Fresh water |
| Author keywords |
nutrients; floating-leaved macrophytes; shallow lakes; biomass |
| Authors | | Top |
- Marion, L.
- Paillisson, J.-M., correspondent
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| Abstract |
In this study we examine the contribution of three floating-leaved macrophyte species, Nymphaea alba, Trapa natans and Nymphoides peltata (covering about 700-750 ha), in the N and P stocks in a shallow eutrophic lake (4000-6300 ha) during a 3-year period (1995-1997). The monthly nutrient standing stocks in the above-ground structures of the plants were derived from biomass, nutrient content and area covered by each plant species during the growth period. These N and P quantities were compared to the net nutrient inputs of the lake waters from the catchment area recorded in the winter (water discharging phase), preceding the vegetation period. N and P contents reached high values for the three species (2.16-3.23% N and 0.29-0.68% P) showing the ability of the plants to accumulate large nutrient contents. Despite significant annual fluctuations in nutrient contents and biomass, not always in the same way for each floating-leaved macrophyte, and changes in the area they covered, the maximum monthly P stocks in the plants were globally uniform between the 3 years (7.10-8.85 tonnes). Maximum values for N ranged from 40.85 to 54.55 tonnes in summer. The vast beds of N. alba (until 75% of the total area in 1997), contributed largely to these annual nutrient stocks (50-72% and 46-70%, respectively, for N and P). Whereas the nutrient stocks estimated in the plants during the biomass peak represented little proportions of the annual net flux of N in the lake waters (3.35-5.00%), they reached high proportions for P sometimes exceeding the annual net loading of P in the lake according to years (16.80-156.25%). These results suggest that the nutrient-enriched sediments of the lake (6-53 and 2-6 times the net annual P and N inputs) probably compensate for annual variations in the external nutrient loading, notably for P, and floating-leaved macrophytes are likely not limited when the inputs from the catchment area are small. |
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