Survivability and Life Support in Sealed Mini-Ecosystems with Simulated Planetary Soils

Sato, T.; Abe, K.; Koseki, J.; Seto, M.; Yokoyama, J.; Akashi, T.; Terada, M.; Kadowaki, K.; Yoshida, S.; Yamashiki, Y. A.; Shimamura, T.

doi:10.1101/2023.11.02.565408

bioRxiv · 10.1101/2023.11.02.565408

Survivability and Life Support in Sealed Mini-Ecosystems with Simulated Planetary Soils

Sato, T.·Abe, K.·Koseki, J.·Seto, M.·Yokoyama, J.·Akashi, T.·Terada, M.·Kadowaki, K.·Yoshida, S.·Yamashiki, Y. A.·Shimamura, T.

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Abstract

Establishing a sustainable life-support system for space exploration is challenging due to the vast distances, costs, and differing environments from Earth. Using insights from the Biosphere 2 experiment, we introduced the "Ecosphere" and "Biosealed" systems in custom containers to replicate Earths ecosystems, suggesting feasible space migration through transplanting Earth-like biomes. Over four years, we gained deeper insights into these enclosed ecosystems. Moisture deficiency was a major obstacle to plant growth, which we addressed by incorporating a groundwater layer in the containers. We underscored the critical role of microorganisms in building and sustaining these ecosystems. However, temperature spikes from sunlight threatened stability. Our experiments confirmed fruit flies survival on plant-produced oxygen and photosynthetic bacteria. Interactions between plants, microbes, and simulated space soils were examined. Detailed analysis unveiled diverse microbes shaping both confined and simulated space environments. Major findings include the symbiotic relationship of plants with cyanobacteria, the potential of LED lighting in sun-limited missions, and challenges with ethylene gas and moisture. Microbial integration in rough soils holds promise for seed germination, but understanding their role in space soils is crucial. Our research offers a comprehensive foundation for future space life-support systems and underlines potential concerns about microbes affecting human health.

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Sato, T., Abe, K., Koseki, J., Seto, M., Yokoyama, J., Akashi, T., Terada, M., Kadowaki, K., Yoshida, S., Yamashiki, Y. A., Shimamura, T.. 2023-11-04. Survivability and Life Support in Sealed Mini-Ecosystems with Simulated Planetary Soils. https://doi.org/10.1101/2023.11.02.565408

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