The MUSCLES project has the aim to collect macrophyte samples from all over the world. Samples will be primarily analyzed on their silica content. The University of Antwerp (Ecosystem Management Research Group – ECOBE) will try to answer research questions such as: Does cosmopolitan species have comparable silica concentrations? Are there differences between boreal, temporal and tropical species? Which species accumulate silicon the most? In a secondary study, strength molecules lignin and cellulose will be determined per species. Can silica content be linked to these molecules?