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The potential plant-available soil water is the difference between wilting point and field capacity (FC). Soil water content at FC is estimated using the approach developed by Assouline and Or (2014) that considers a dynamic definition of FC based on soil-specific matric potential values beyond which the soil water continuity is substantially reduced or disrupted. For calculations of soil water content at FC we use the van Genuchten soil water characteristic curves from Gupta et al., (2022). Furthermore, we introduce the climatic plant-available soil water that considers potential evaporation and the average number of consecutive dry days between rainfall events. The consecutive dry days were obtained from Bickel and Or (2021). This repository contains four global maps at 1km resolution per 1m soil depth: matric potential at FC [m] water content at FC [m3/m3] potential plant-available soil water [mm] climatic plant-available soil water [mm] For additional details and to cite this dataset please refer to: Gupta, S., Lehmann, P., Bickel, S., Bonetti, S., & Or, D. (2023). Global mapping of potential and climatic plant-available soil water. Submitted to Journal of Advances in Modeling Earth Systems. The study was supported by ETH Zurich (Grant ETH-18 18-1). References: Assouline, S., & Or, D. (2014). The concept of field capacity revisited: Defining intrinsic static and dynamic criteria for soil internal drainage dynamics. Water Resources Research, 50(6), 4787-4802. Bickel, Samuel, & Or, Dani. (2021). Dataset of global climatic soil water contents and consecutive dry days [Data set]. Zenodo.https://doi.org/10.5281/zenodo.5078258 Gupta, Surya, Papritz, Andreas, Lehmann, Peter, Hengl, Tomislav, Bonetti, Sara, & Or, Dani. (2022). Global maps of soil water characteristics parameters developed using the random forest in a Covariate-based GeoTransfer Functions (CoGTF) framework at 1 km resolution [Data set]. Zenodo. https://doi.org/ 10.5281/zenodo.6343570

Global land surface models use spatially distributed soil information for the parameterization of soil hydraulic properties (SHP). Parameters of measured SHP are correlated with easy‐to‐measure soil properties to construct general pedotransfer functions (PTFs) used to predict SHP from spatial soil information. Global PTFs are based on a limited number of samples yielding highly variable and poorly constrained SHP. The study implements a physical constraint, soil‐specific capillary length, to reduce unphysical combinations of SHP. The procedure fits concurrently soil water retention and capillary length using the same parameters. Results suggest that meeting the capillary length constraint has minor effects on the goodness of fit to soil water retention data. Constrained SHP were applied to represent 4 years of lysimeter fluxes yielding evapotranspiration values in close agreement with measurements relative to slight overestimation by unconstrained SHP. The procedure was applied for testing constraint SHP at a regional scale in New Zealand using the surface evaporation capacitance model and Noah‐MP for detailed simulations of land surface processes. The use of constrained SHP in both models yields higher surface runoff in agreement with observations (unconstrained SHP severely underestimated runoff generation). The concept of constrained SHP could be extended to include other physical constraints to improve PTFs, for example, by consideration of vegetation cover and soil structure effects on infiltration., Water Resources Research, 56 (4), ISSN:0043-1397, ISSN:1944-7973

Geophysical Research Abstracts, 21, ISSN:1029-7006, ISSN:1607-7962

AGU Fall Meeting Abstracts

Geophysical Research Abstracts, 19, ISSN:1029-7006, ISSN:1607-7962

Book, 3rd International SystemsX.ch Conference on Systems Biology

Book: 2016 International Symposium on Microbial Ecology (ISME 16)

Soil bacterial communities are central to ecosystem functioning and services, yet spatial variations in their composition and diversity across biomes and climatic regions remain largely unknown. We employ multivariate general additive modeling of recent global soil bacterial datasets to elucidate dependencies of bacterial richness on key soil and climatic attributes. Although results support the well-known association between bacterial richness and soil pH, a hierarchy of novel covariates offers surprising new insights. Defining climatic soil water content explains both, the extent and connectivity of aqueous micro-habitats for bacterial diversity and soil pH, thus providing a better causal attribution. Results show that globally rare and abundant soil bacterial phylotypes exhibit different levels of dependency on environmental attributes. Surprisingly, the strong sensitivity of rare bacteria to certain environmental conditions improves their predictability relative to more abundant phylotypes that are often indifferent to variations in environmental drivers., Scientific Reports, 9 (1), ISSN:2045-2322

Soil bacterial diversity varies across biomes with potential impacts on soil ecological functioning. Here, we incorporate key factors that affect soil bacterial abundance and diversity across spatial scales into a mechanistic modeling framework considering soil type, carbon inputs and climate towards predicting soil bacterial diversity. The soil aqueous-phase content and connectivity exert strong influence on bacterial diversity for each soil type and rainfall pattern. Biome-specific carbon inputs deduced from net primary productivity provide constraints on soil bacterial abundance independent from diversity. The proposed heuristic model captures observed global trends of bacterial diversity in good agreement with predictions by an individual-based mechanistic model. Bacterial diversity is highest at intermediate water contents where the aqueous phase forms numerous disconnected habitats and soil carrying capacity determines level of occupancy. The framework delineates global soil bacterial diversity hotspots; located mainly in climatic transition zones that are sensitive to potential climate and land use changes., Nature Communications, 11, ISSN:2041-1723