Silicon in aquatic vegetation
Faculty of Sciences. Biology
Functional ecology / British Ecological Society. - Oxford
, p. 1323-1330
University of Antwerp
Silicon (Si) use by plants has not always received the research attention of other elements. Yet today, the importance of Si for plant functioning is slowly becoming better understood. Si is a crucial element for many terrestrial plant species (especially grasses), yet a recent surge of research has shown that some species of aquatic plants contain significant amounts of Si too. We argue that degree of Si accumulation is a functional trait in aquatic vegetation, with plants adapting to environmental conditions. Aquatic vegetation can show apparent plasticity regarding Si uptake, adaptive to water and wind dynamics, light interception, herbivory and nutrient stress. Beyond a plant physiological viewpoint, high Si uptake results in high BSi in plant litter, which can impact on aquatic decomposition processes. Si content in aquatic vegetation shows intriguing relations with other strength components such as cellulose and lignin. Si content has also been linked to fungal and microbial community, litter stoichiometry and invertebrate shredders: all factors that potentially influence organic turnover in aquatic sediments. Uptake of Si by aquatic vegetation is thus not only an important transient sink for Si in the global biogeochemical Si cycle, it can also affect carbon turnover in aquatic ecosystems. Experimental and field studies should be conducted to elucidate controls on aquatic plant Si uptake, especially focusing on interactive effects of multiple biotic and abiotic factors. This review provides an overview of the state-of-the-art knowledge on silicon in aquatic vegetation.