Silica uptake in aquatic and wetland macrophytes: a strategic choice between silica, lignin and cellulose?
*Although silica (Si) is not an essential element for plant growth in the classical sense, evidence points towards its functionality for a better resistance against (a)biotic stress. Recently, it was shown that wetland vegetation has a considerable impact on silica biogeochemistry. However, detailed information on Si uptake in aquatic macrophytes is lacking. *We investigated the biogenic silica (BSi), cellulose and lignin content of 16 aquatic/wetland species along the Biebrza river (Poland) in June 2006 and 2007. The BSi data were correlated with cellulose and lignin concentrations. *Our results show that macrophytes contain significant amounts of BSi: between 2 and 28 mg BSi g(-1). This is in the same order of magnitude as wetland species (especially grasses). Significant antagonistic correlations were found between lignin, cellulose and BSi content. Interestingly, observed patterns were opposite for wetland macrophytes and true aquatic macrophytes. *We conclude that macrophytes have an overlooked but potentially vast storage capacity for Si. Study of their role as temporal silica sinks along the land-ocean continuum is needed. This will further understanding of the role of ecosystems on land ocean transport of this essential nutrient.
Department of Biology, Ecosystem Management Research Group, University of Antwerp, Universiteitsplein 1C, B-2610 Wilrijk, Belgium. jonas.schoelynck@ua.ac.be
Jonas
J
Schoelynck
Kris
K
Bal
Hans
H
Backx
Tomasz
T
Okruszko
Patrick
P
Meire
Eric
E
Struyf
D018533:Biomass; D002482:Cellulose / Q000378:metabolism*; D005843:Geography; D008031:Lignin / Q000378:metabolism*; D010944:Plants / Q000378:metabolism*; D011044:Poland; D012822:Silicon Dioxide / Q000378:metabolism*; D014867:Water; D053833:Wetlands
D014867:Water; D012822:Silicon Dioxide; D002482:Cellulose; D008031:Lignin