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.

Soil organic matter is one of the largest stores of carbon and nitrogen in various ecosystems that can crucially improve plant nutrition. The present study was conducted to investigate the effect of organic matter sources on carbon and nitrogen mineralization and also the contemporary comparison of carbon and nitrogen mineralization and nitrogen immobilization in soils amended with different organic treatments. Accordingly, six types of organic amendments were applied to three types of soils, under a constant temperature and moisture at the laboratory scale. The treated soils were incubated 60 and 120 days for nitrogen and carbon mineralization study, respectively. Results showed two decomposition stages, an initial rapid increase in decomposition in the first 20 days followed by a slower stage reaching a steady state condition. The amount of mineralized carbon ranged from 980 to 6860 mg/kg of dry soil for soils incorporating with different types of organic matters. The carbon mineralization kinetic data was well fitted to a second-order kinetic model showing the differences in microbial decomposition resistance of residues contents. The kinetic of carbon and nitrogen mineralization fluctuated similarly but in different scales. Net ammonification of fertilizer group, sheep manure, cow manure, and vermicompost was decreased, whereas in plant residue group, plane tree leaves, corn leaves, and wheat straw was increased. Two nitrification periods (first 10 days and 35 to 60 days) and an immobilization period (10 to 35 days) were observed. After 60 days of incubation of amended clayey soil, the nitrification values in plane tree leaves, corn leaves, wheat straw, municipal waste vermicompost, cow manure, and sheep manure were − 13.98, 14.06, 13.22, 34.88, − 12.25, and − 12.15 mg kg −1 , respectively. The carbon and nitrogen mineralization trends fluctuated due to probably different resistance of substance components to microbial decomposition. Since the nitrate is the main part of inorganic N, therefore, net N mineralization had a similar trend as nitrification in different soils. Those organic residues with high ratios of C/N immobilized the mineral nitrogen, due to the presence of more carbon and a higher nitrogen decomposition rate, resulting in suppressed levels of nitrogen in the amended soil.

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Abstract. In this paper, we present and analyze a global database of soil infiltration measurements, the Soil Water Infiltration Global (SWIG) database, for the first time. 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 USA. In addition to its global spatial coverage, the collected infiltration curves cover a time span of research from 1976 to late 2017. Basic information on measurement location and method, soil properties, and land use were gathered along with the infiltration data, which makes the database valuable for the development of pedo-transfer functions 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 the land use is available for 76 % of 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 use by public domain only and can be copied freely by referencing it. Supplementary data are available at doi:10.1594/PANGAEA.885492. Data quality assessment is strongly advised prior to any use of this database. Finally, we would like to encourage scientists to extend/update the SWIG by uploading new data to it.