## 5 Conclusions  
As summarized in Figure 7, the integrated metagenomic and biochemical evidence presented in this study characterized a mechanism for H\({}_{2}\)-based irrigation function in strawberry yield improvement, possibly achieved by the alteration of rhizosphere microbial communities and the increased plant nutrient uptake capacity. The contribution of microbe-mediated soil C, N, and P cycles was elucidated as well. However, it should be noted that the microbial effects achieved by H\({}_{2}\) might be influenced by plant species and environmental conditions. Since the possibility that the potential negative effects of H\({}_{2}\) on soil ecosystems are not easily ruled out, the agricultural application of H\({}_{2}\) requires the large-scale and long-term field trials. Overall, the results of this study will not only widen our basic knowledge of hydrogen biology but very likely also improve our understanding of low-carbon H\({}_{2}\)-based agriculture that may increase crop (including horticulture, etc.) yield in a sustainable manner. **Supplementary Materials:** The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/plants13131723/s1](https://www.mdpi.com/article/10.3390/plants13131723/s1)]([https://www.mdpi.com/article/10.3390/plants13131723/s1](https://www.mdpi.com/article/10.3390/plants13131723/s1)), Figure S1: Hydrogen-based irrigation improves strawberry growth; Figure S2: Changes in soil available nitrogen (SAN; A), soil available phosphorus (SAP; B), soil available potassium (SAK; C), and soil organic matter (SOM; D) contents after HNW irrigation without/with fertilizers; Figure S3: Analysis of similarities (ANOSIM) based on Bray-Curtis dissimilarity at the genus level; Figure S4: Relative abundances of rhizosphere degrees; Figure S5: Photographs of strawberry field and representative plants were taken on 14 January 2021 (A) and 14 February 2023 (B); Figure S6: The monthly maximum and minimum temperature and total precipitation during strawberry planting. Table S1: Strawberry yield in response to hydrogen-based irrigation; Table S2: Results of one-way analysis of variance (ANOVA) and \(t\)-test between treatments for Figure 2D; Table S3: Relative abundances (%) of dominant genera (Top 30) of bacterial community; Table S4: Results of \(t\)-test between treatments for Figure S4; Table S5: Results of \(t\)-test between treatments for Figures 3 and 4; Table S6: Results of Pearson's correlation among carbon, nitrogen, and phosphorus cycling genes for Figure 5A; Table S7: Results of Pearson's correlation among genes related to carbon, nitrogen, and phosphorus cycling, yield and soil properties for Figure 5B; Table S8: Overview of soil metagenome sequencing and annotation results; Table S9: Primers used for qPCR. **Author Contributions:** Conceptualization, L.L. and W.S. ; investigation, K.J. ; data curation, L.L. and K.J. ; writing--original draft preparation, L.L. ; writing--review and editing, L.L., W.S., H.H., Z.J., Y.Z., D.P. and X.C. ; supervision, D.P. and X.C. ; project administration, W.S. and Y.Z. ; funding acquisition, W.S. All authors have read and agreed to the published version of the manuscript. **Funding:** This work was financially supported by Jiangsu Province Agricultural Science and Technology Independent Innovation Project (CX(22)3155), Air Liquide (China) R&D Co., Ltd. and Shanghai Key Laboratory of Hydrogen Science, Center of Hydrogen Science, Shanghai Jiao Tong University, China. Figure 7: An overall schema illustrating the contribution of microbe-mediated soil carbon, nitrogen, and phosphorus cycles and plant nutrient uptake capacity in strawberry yield improvement by hydrogen-based irrigation. The colors of genes denote alterations in abundance or expression in rhizosphere microbial communities or strawberry roots achieved by hydrogen nanobubble water (HNW), compared to the corresponding control, respectively. Red indicates a significant increase; blue indicates a significant decrease; and gray indicates no significant difference.