Investigation on growth of peat moss Sphagnum palustre L. in different photobioreactors

Sphagnum founder material used for the restoration of rewetted bogs and installation of Sphagnum paludiculture areas can be provided by submerged cultivation in photobioreactors (PBRs). This study represents the first investigation of the photoautotrophic cultivation of Sphagnum palustre L. in different PBRs at laboratory scale. One commercially available reactor - a 60 L flat-panel bioreactor - along with three self-developed PBRs - a 3 L wave-bag bioreactor, a 10 L bottle bioreactor and a 50 L tank bioreactor - were used. Using an inorganic Sphagnum medium , artificial light, and CO 2 enriched air, the moss morphology, biomass productivity, specific power input and specific light availability were determined. The results suggest that the wave-bag bioreactor is not suitable for Sphagnum cultivation, while for the bubble columns, a minimum superficial gas velocity u g and specific power input ( P G /V L ), as well as specific light intensity ( I spec ), are decisive process parameters. Submerse, photoautotrophic production of Sphagnum palustre L. in a bubble column PBR is highly feasible (0.14 ± 0.03 g L −1 d −1 ), and this reactor type shows potential for Sphagnum founder material production for peatland rewetting due to its simplicity and low pneumatic power input (9.9 W m −3 ). Investigation on growth of peat moss Sphagnum palustre L. in different photobioreactors • Four photobioreactors for the production of Sphagnum palustre • 0.14 ± 0.03 g L −1 d −1 dry biomass productivity under photo-autotrophic condition • Power input, gas transfer, light availability and photoconversion efficiency data • Comparison of Sphagnum palustre morphologies from different photobioreactors