Ng Charles Wang Wai, Wang Yu Chen
Department of Civil and Environmental Engineering, the Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR, China.
NPJ Microgravity. 2025 Jul 2;11(1):31. doi: 10.1038/s41526-025-00491-y.
Cultivating plants in outer space is crucial for bioregenerative life support systems in human space exploration. This study aims to investigate the effects of soil conditioning with biochar and hydrochar on the growth and production of Malabar Spinach in microgravity conditions. Peanut shell biochar and wood hydrochar were applied at a 3% dosage by mass. Two gravity conditions were considered, including 1 g and microgravity simulated by a Random Positioning Machine (RPM). After an 18-day plant growth period, microgravity reduced the fresh biomass accumulation of Malabar Spinach by up to 71%. This reduction was attributed to inhibited leaf and root growth, which decreased light interception and nutrient uptake. In microgravity, biochar was more effective than hydrochar in enhancing plant production, mitigating the growth inhibition caused by microgravity. In the presence of biochar, microgravity significantly enhanced the biosynthesis of chlorophyll a and carotenoids by up to 36%. Furthermore, biochar and hydrochar treatments in microgravity conditions significantly increased the nutrient contents, such as K and P, in Malabar Spinach leaves. These findings indicate that biochar and hydrochar are promising soil conditioners for enhancing plant development in low-gravity conditions.
在人类太空探索中，在外层空间种植植物对于生物再生生命支持系统至关重要。本研究旨在探究生物炭和水炭改良土壤对微重力条件下马拉巴菠菜生长和产量的影响。花生壳生物炭和木材水炭按质量比3%施用。考虑了两种重力条件，包括1g重力以及由随机定位机（RPM）模拟的微重力。在18天的植物生长周期后，微重力使马拉巴菠菜的鲜生物量积累减少了高达71%。这种减少归因于叶片和根系生长受到抑制，从而降低了光截获和养分吸收。在微重力环境下，生物炭在提高植物产量方面比水炭更有效，减轻了微重力对生长的抑制作用。在有生物炭存在的情况下，微重力显著增强了叶绿素a和类胡萝卜素的生物合成，增幅高达36%。此外，在微重力条件下生物炭和水炭处理显著增加了马拉巴菠菜叶片中的钾和磷等养分含量。这些发现表明，生物炭和水炭是在低重力条件下促进植物生长的有前景的土壤改良剂。
