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Molecular hydrogen (H₂) is the second most abundant reduced trace gas (after methane) in the atmosphere, but its biogeochemical cycle is not well understood. Our study focuses on the soil production and uptake of H₂ and the associated isotope effects. Air samples from a grass field and a forest site in the Netherlands were collected using soil chambers. The results show that uptake and emission of H₂ occurred simultaneously at all sampling sites, with strongest emission at the grassland sites where clover (N₂ fixing legume) was present. The H₂ mole fraction and deuterium content were measured in the laboratory to determine the isotopic fractionation factor during H₂ soil uptake (&alpha;_soil) and the isotopic signature of H₂ that is simultaneously emitted from the soil (δD_soil). By considering all net-uptake experiments, an overall fractionation factor for deposition of &alpha;_soil = <i>k</i>_HD / <i>k</i>_HH = 0.945 ± 0.004 (95 % CI) was obtained. The difference in mean &alpha;_soil between the forest soil 0.937 ± 0.008 and the grassland 0.951 ± 0.026 is not statistically significant. For two experiments, the removal of soil cover increased the deposition velocity (<i>v</i>_d) and &alpha;_soil simultaneously, but a general positive correlation between <i>v</i>_d and &alpha;_soil was not found in this study. When the data are evaluated with a model of simultaneous production and uptake, the isotopic composition of H₂ that is emitted at the grassland site is calculated as δD_soil = (−530 ± 40) &permil;. This is less deuterium depleted than what is expected from isotope equilibrium between H₂O and H₂.