Abstract. In this paper, we present and analyze a novel global database of soil infiltration measurements, the Soil Water Infiltration Global (SWIG) database. In total, 5023 infiltration curves were collected across all continents in the SWIG database. These data were either provided and quality checked by the scientists who performed the experiments or they were digitized from published articles. Data from 54 different countries were included in the database with major contributions from Iran, China, and the USA. In addition to its extensive geographical coverage, the collected infiltration curves cover research from 1976 to late 2017. Basic information on measurement location and method, soil properties, and land use was gathered along with the infiltration data, making the database valuable for the development of pedotransfer functions (PTFs) for estimating soil hydraulic properties, for the evaluation of infiltration measurement methods, and for developing and validating infiltration models. Soil textural information (clay, silt, and sand content) is available for 3842 out of 5023 infiltration measurements (∼ 76%) covering nearly all soil USDA textural classes except for the sandy clay and silt classes. Information on land use is available for 76 % of the experimental sites with agricultural land use as the dominant type (∼ 40%). We are convinced that the SWIG database will allow for a better parameterization of the infiltration process in land surface models and for testing infiltration models. All collected data and related soil characteristics are provided online in *.xlsx and *.csv formats for reference, and we add a disclaimer that the database is for public domain use only and can be copied freely by referencing it. Supplementary data are available at https://doi.org/10.1594/PANGAEA.885492 (Rahmati et al., 2018). Data quality assessment is strongly advised prior to any use of this database. Finally, we would like to encourage scientists to extend and update the SWIG database by uploading new data to it.

Lysimeter experiments were conducted with sandy-clay-loam soil to study the efficiency of two amendments in reclaiming saline-sodic soil using moderately saline and SAR (sodium-adsorption ratio) irrigation water. Gypsum obtained from industrial phosphate by-products and reagent grade Ca chloride were applied to packed soil columns and irrigated with moderately saline (ECe = 2.16 dS m -1 ), moderate-SAR water (SAR = 4.8). Gypsum was mixed with soil prior to irrigation at application rates of 5, 10, 15, 20, 25, and 32 Mg ha -1 , and Ca chloride was dissolved directly in leaching water at application rates of 4. 25, 8.5, 12.75, 17.0, and 21.25 Mg ha -1 , respectively. The highest application rate in both amendments resulted in 96% reduction of total Na in soil. The hydraulic conductivity (HC) of soils receiving gypsum increased in all treatments. The highest HC value of 6.8 mm h -1 was obtained in the highest application rate (32 Mg ha -1 ), whereas the lowest value of 5.2 mm h -1 was observed with the control treatment. Both amendments were efficient in reducing soil salinity and sodicity (exchangeable-sodium percentage, ESP); however, Ca chloride was more effective than gypsum as a reclaiming material. Exchangeable Na and soluble salts were reduced with gypsum application by 82% and 96%, and by 86% and 93% with Ca chloride application, respectively. Exchangeable Ca increased with increasing amendment rate. Results of this study revealed that sodium was removed during cation-exchange reactions mostly when the SAR of effluent water was at maximum with subsequent passage of 3 to 4 pore volumes. Gypsum efficiently reduced soil ESP, soil EC, leaching water, and costs, therefore, an application rate of 20 Mg ha -1 of gypsum with 3 to 4 pore volumes of leaching water is recommended for reclaiming the studied soil.

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Fifteen soil profiles were taken from ArRamtha wastewater treatment plant, 65 km north of Amman. Twelve of them represent soil planted with barley and irrigated with wastewater for the past 2, 5, and 15 years. The remaining three profiles represented a control area that has been only rainfed. Soil samples were collected in four replicates from each depth in each soil profile. Field and laboratory experiments were conducted to study the effect of irrigation with treated wastewater on hydraulic properties of surface and subsurface vertisols. Soil infiltration rate (IR), hydraulic conductivity (HC), and water retention (at 33 kPa and 1.5 MPa) were measured. The application of wastewater for 2, 5, and 15 years reduced soil hydraulic conductivity, whereas the infiltration rate decreased for 2 and 5 years, compared with non-irrigated area. Sites irrigated for 15 years with treated wastewater are characterized by higher percentages of large cracks, therefore revealed the highest infiltration rate. Soil available water changed due to wastewater application in decreasing order of: control (rainfed), 15, 5, 2 years of wastewater application.