Development and analysis of the Soil Water Infiltration Global database

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

Maintaining the hyper-arid forests of Abu Dhabi by sustainable irrigation using treated sewage effluent in conjunction with groundwater : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy (PhD) in Soil and Environmental Sciences, School of Agriculture and Environment, Massey University, Palmerston North, New Zealand

The late H.H Sheikh Zayed bin Sultan Al Nahyan, the founding President of the United Arab Emirates sought to ‘green the desert’ through planting of trees. These forests in the hyperarid desert of Abu Dhabi depend on irrigation with groundwater (GW). A wide range of valuable ecosystem services are delivered by the forests. In the 2017 State of the Environment Report, Environment Agency – Abu Dhabi (EAD) noted that “… considerable water resources are required to maintain these forests”. Over-consumption of GW, and the increasing salinity of the aquifers means that the GW of Abu Dhabi is under threat. To manage sustainably the GW resources, in 2016 the government of Abu Dhabi passed Law 5 on GW management and identified the requirement for limits to be placed on GW allocation for vegetation. The means to realise reductions in GW use are: minimised irrigation schedules for GW; and the replacement of GW with treated sewage effluent (TSE). To achieve this, a Government-to-Government partnership was established between EAD and the New Zealand Government. The NZ partners are Maven International and Plant & Food Research. This doctoral research was carried out under this larger partnership. The actual water uses, ETc, of the 3 major forest species of Al Ghaf, Al Sidr and Al Samr were measured by heat-pulse sapflow methods in trees irrigated with either GW or TSE. The impacts on ETc and tree health of the lower salinity TSE are detailed. The complex links between tree water-use, the reference ETo, and trees’ phenology are described. Relationships between the crop factor, Kc (=ETc/ETo), and tree canopy characteristics were inferred using a light-stick to measure the percentage light intercepted by the trees’ canopy. From this research, guidelines have been proposed for Law 5 for the water-allocation limits for these 3 species. These guideline values for GW are based on 1.5 ETc to account for a 25% factor-of-safety, and a 25% salt-leaching fraction. For TSE, there is no need for salt leaching. These recommendations will lead to GW savings of 35-70% compared to current practice. Eventually TSE should replace GW to sustain the forests

Development and analysis of the Soil Water Infiltration Global database

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

Development and analysis of the Soil Water Infiltration Global database

© Author(s) 2018. 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 76ĝ€% 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.status: publishe