HYDRUS Model Data From 2022 Finkenbiner Study On Soil Isotope Separation

Brief Summary:
Soil physics simulations showed water isotope ratios can differ among drainage, mobile and immobile storages due to transport processes alone, but effects were smaller than field data implying unrepresented processes underly ecohydrologic separation.

Manuscript Abstract:
Field measurements of hydrologic tracers indicate varying magnitudes of geochemical separation between subsurface pore waters. The potential for conventional soil physics alone to explain isotopic differences between preferential flow and tightly-bound water remains unclear. Here, we explored physical drivers of isotopic separations using 650 different model configurations of soil, climate, and mobile/immobile soil-water domain characteristics, without confounding fractionation or plant uptake effects. We find simulations with coarser soils and less precipitation led to reduced separation between pore spaces and drainage. Amplified separations were found with larger immobile domains and, to a lesser extent, higher mobile-immobile transfer rates. Nonetheless, isotopic separations remained small (<4‰ for d2H) across simulations, indicating that contrasting transport dynamics generate limited geochemical differences. Therefore, conventional soil physics alone are unlikely to explain large ecohydrological separations observed elsewhere, and further efforts aimed at reducing methodological artifacts, refining understanding of fractionation processes, and investigating new physiochemical mechanisms are needed.

Dataset Information:
This dataset contains HYDRUS model output used to create four figures in a study by C. Finkenbiner of the ability of soil physics models to represent isotopic separation. Within the four provided folders are model output files with filenames describing their contents. Simulations were ran for 300 days, with the last 100 days used for analysis provided here. Output files are csv files that contain H2 isotope ratios, soil moisture, or soil drainage values across 10 simulations, denoted pv1 - pv10. Simulations were configured to have high, low or zero fractions of immobile soil pore space, denoted as Hf, Lf, and 0f respectively in filenames. Simulations with immobile pore spaces were also configured to have high and low transfer coefficients, denoted as Hw and Lw in file names. For more information please see Finkenbiner et. al. 2022 in Nature Communications (DOI: 10.1038/s41467-022-34215-7) or contact Stephen Good at Oregon State University.

简要概述：
土壤物理学模拟表明，仅因传输过程，排水、移动和不可移动储存中的水同位素比可能存在差异，但效果小于实地数据，暗示在生态水文分离中存在未被表征的过程。

手稿摘要：
水文示踪剂实地测量表明，地下孔隙水中存在不同程度的地球化学分离。仅凭传统土壤物理学来解释优先流和紧密结合的水之间同位素差异的可能性尚不明确。在此，我们通过使用650种不同的土壤、气候和移动/不可移动土壤-水域特征模型配置，探讨了同位素分离的物理驱动因素，同时排除了混合分离或植物吸收效应的干扰。我们发现，土壤质地较粗、降水量较低的模拟导致孔隙空间和排水之间的分离度降低。在较大的不可移动域和一定程度上的移动-不可移动转移率较高的情况下，分离度得到了增强。然而，模拟中的同位素分离仍然较小（d2H小于4‰），表明对比的传输动力学产生了有限的地球化学差异。因此，仅凭传统土壤物理学无法解释在其他地方观察到的较大生态水文分离，需要进一步的努力来减少方法学上的伪象，细化对混合过程的理解，并研究新的物理化学机制。

数据集信息：
本数据集包含用于创建C. Finkenbiner研究中的四个图表的HYDRUS模型输出，以探究土壤物理学模型在表征同位素分离方面的能力。在提供的四个文件夹中包含模型输出文件，文件名描述了其内容。模拟进行了300天，最后100天用于此处提供的数据分析。输出文件是csv文件，包含10个模拟的H2同位素比、土壤水分或土壤排水值，分别标记为pv1 - pv10。模拟配置为具有高、低或零不可移动土壤孔隙空间比例，分别用文件名中的Hf、Lf和0f表示。具有不可移动孔隙空间的模拟还配置了高和低转移系数，分别用文件名中的Hw和Lw表示。更多详细信息请参阅Nature Communications（DOI: 10.1038/s41467-022-34215-7）中的Finkenbiner等人的2022年文章或联系俄勒冈州立大学的Stephen Good。