Description of the unsaturated soil hydraulic database UNSODA version 2.0

Quantifying water flow and chemical transport in the vadose zone typically requires knowledge of the unsaturated soil hydraulic properties. The UNsaturated SOil hydraulic DAtabase (UNSODA) was developed to provide a source of unsaturated hydraulic data and some other soil properties for practitioners and researchers. The current database contains measured soil water retention, hydraulic conductivity and water diffusivity data as well as pedological information of some 790-soil samples from around the world. A first MS-DOS version of the database was released in 1996. It has been applied in numerous studies. In this paper, we describe the second version (UNSODA V2.0) for use with Microsoft Access-97®1. The format and structure of the new database have been modified to provide additional and more convenient options for data searches, to provide compatibility with other programs for easy loading and downloading of data, and to allow users to customise the contents and look of graphical output. This paper reviews the structure and contents of the database as well as the operations that can be performed on the different data types in UNSODA V2.0. The use and application of the new database are illustrated with two examples. The retrieval of data is briefly illustrated, followed by a more detailed example regarding the interpolation of soil particle-size distribution data obtained according to different national definitions of particle-size classes. The interpolation procedure, which is based on finding similar particle-size distribution curves from a large European data set, also performed well for soils that originate from other geographical areas.

[1]  Peter J. Shouse,et al.  Scaling Parameter to Predict the Soil Water Characteristic from Particle-Size Distribution Data , 1999 .

[2]  Walter J. Rawls,et al.  Estimating Soil Water Retention from Soil Physical Properties and Characteristics , 1991 .

[3]  Ken'ichirou Kosugi,et al.  General model for unsaturated hydraulic conductivity for soils with lognormal pore-size distribution. , 1999 .

[4]  Peter Finke.  Bodeminventarisatie - van gegevensverzameling tot informatieverstrekking , 1995 .

[5]  B. A. Stewart,et al.  Advances in Soil Science , 1986, Advances in Soil Science.

[6]  Alexandra N. Kravchenko,et al.  ESTIMATING THE SOIL WATER RETENTION FROM PARTICLE-SIZE DISTRIBUTIONS: A FRACTAL APPROACH , 1998 .

[7]  J. Sevink,et al.  Van bodemkaart tot informatiesysteem. , 1995 .

[8]  M. Schaap,et al.  Neural network analysis for hierarchical prediction of soil hydraulic properties , 1998 .

[9]  Anderson L. Ward,et al.  Innovations in Two-Phase Measurements of Soil Hydraulic Properties , 1999 .

[10]  Marcel G. Schaap,et al.  Improved Prediction of Unsaturated Hydraulic Conductivity with the Mualem‐van Genuchten Model , 2000 .

[11]  Km Rosenthal,et al.  WARIS - a computer based storage and retrieval system for soils and related data , 1986 .

[12]  Attila Nemes,et al.  Evaluation of different procedures to interpolate particle-size distributions to achieve compatibility within soil databases , 1999 .

[13]  Feike J. Leij,et al.  Closed‐Form Expressions for Water Retention and Conductivity Data , 1997 .

[14]  Walter J. Rawls,et al.  Pedotransfer functions: bridging the gap between available basic soil data and missing soil hydraulic characteristics , 2001 .

[15]  J. Wösten,et al.  Development and use of a database of hydraulic properties of European soils , 1999 .

[16]  Ole H. Jacobsen,et al.  PREDICTING SATURATED AND UNSATURATED HYDRAULIC CONDUCTIVITY IN UNDISTURBED SOILS FROM SOIL WATER CHARACTERISTICS , 1999 .

[17]  V. W. P. van Engelen,et al.  Global and national soils and terrain digital databases (SOTER): procedures manual. , 1993 .

[18]  Peter J. Shouse,et al.  Relationship between the Hydraulic Conductivity Function and the Particle‐Size Distribution , 2003 .

[19]  Marcel G. Schaap,et al.  Database-related accuracy and uncertainty of pedotransfer functions , 1998 .