There have been several published reports regarding the growth promoting effect of humic acids (HA) on vascular plants; however, the effect of HA on bryophytes is still unknown. Due to the ecological importance of mosses, which dominate the Antarctic flora, we assessed the effectiveness of HA as a biostimulant using three moss species: Antarctic Ceratodon purpureus KMA5038, Arctic Bryum sp. KMR5045, and Physcomitrella patens which inhabits temperate regions. Natural HA (KS1-3_HA) were extracted through acidic precipitation of alkaline extracts from Antarctic tundra soil. Spectroscopic structural properties of KS1-3_HA were characterized and determined to possess several functional groups such as hydroxyl (R–OH) and carboxyl (R–COOH), implying they could have a growth-related biological function. For two polar mosses, increasing HA concentrations correlated with increased growth and photosynthesis. The efficiency for temperate moss increased at lower concentrations tested, but rather began to reduce at the highest HA concentration, indicating that effective concentrations of HA vary depending on the moss species and habitat. Based on these results, Antarctic HA may have ecological role in enhancing the growth and photosynthesis of Antarctic mosses. We believe this is the first study to establish a positive physiological effect of HA on mosses and hope it may serve as a basis for studying the role of HA in preserving the terrestrial ecosystem of Antarctica.

关于腐殖酸（HA）对维管植物的生长促进作用，已有几篇已发表的报道。但是，HA对苔藓植物的作用仍然未知。由于苔藓，其中占主导地位的南极动植物的生态重要性，我们评估HA的有效性，使用三个苔藓物种生物兴奋剂：南极角齿藓KMA5038，北极真藓菌。KMR5045和Physcomitrella patens居住在温带地区。天然HA（KS1-3_HA）通过对南极冻原土壤中碱性提取物的酸性沉淀来提取。表征并确定KS1-3_HA的光谱结构性质具有几个官能团，例如羟基（R-OH）和羧基（R-COOH），这意味着它们可能具有与生长相关的生物学功能。对于两个极性苔藓，HA浓度增加与生长和光合作用增加相关。在较低的测试浓度下，温带苔藓的效率有所提高，但在最高的HA浓度下却开始降低，这表明HA的有效浓度取决于苔藓物种和栖息地。基于这些结果，南极HA可能在促进南极苔藓的生长和光合作用方面具有生态作用。