Aquatic bryophytes as biofilters and resource regenerators in Bioregenerative Life Support Systems: the moss on Mars project

Bioregenerative Life Support Systems (BLSSs) are closed-loop systems that rely on biological processes, primarily involving plants, algae, andmicrobes, for sustaining long-term space missions by regenerating essential resources and recycling waste. To reduce dependency on resupply from Earth,these systems require highly efficient biological components capable of performing multiple ecological functions in constrained environments.However, research on potential BLSS components has so far focused predominantly on higher plants and algae, with aquatic bryophytes largely overlooked despite their physiological resilience, simple cultivation, and multifunctional ecological roles. This gap limits the diversification of biological components available for optimizing BLSS efficiency.. Here, we investigate for the first time the potential This study investigates the potential introduction of aquatic bryophytes (mosses),specifically Taxiphyllum barbieri, Leptodictyum riparium, and Vesicularia montagnei, as biofilters and resource regenerators in BLSSs. Known for their adaptability, simplicity of growth, and high surface-to-volume ratio, mosses are promising candidates for controlled-environment applications. This paper characterizes mosses' performance considering gas-exchange, chlorophyll fluorescence, antioxidant activity, and biofiltration efficiency under two different controlled temperature and light conditions (24°C and 600mmolphotons m-2s-1, 22°C and 200mmol photons m-2s-1) to determine the most suitable species for the above mentioned purposes