World Soil Information Service (WoSIS) - Procedures for standardizing soil analytical method descriptions

N.H. Batjes, A.J.M. van Oostrum

Research output: Book/ReportReportProfessional

Abstract

This report describes general principles for standardizing soil properties/observations that are served from WoSIS (World Soil Information Service) as ‘wosis_latest’. Data for nominally similar soil properties, collated from disparate sources, are grouped according to major features of the corresponding analytical methods; that is, the properties are grouped according to ‘operational
definitions’. For example, major features for defining soil pH, for example, are the sample pretreatment, extractant solution (water or salt solution), and in case of salt solutions the salt concentration (molarity), as well as the soil/solution ratio. A further descriptive element may be the type of instrument used for the actual laboratory measurement.
Currently, the following list of chemical and physical properties is standardized:
a) Chemical properties: organic carbon, total carbon, total carbonate equivalent, total nitrogen, phosphorus (extractable P,total P and P retention), soil pH, cation exchange capacity, and electrical conductivity.
b) Physical properties: soil texture (sand, silt, and clay), bulk density, coarse fragments, and water retention.
Full data harmonization in a global context, the ultimate objective of WoSIS, will first become feasible once results of extensive proficiency testing programmes become freely available and a common set of ’international’ reference methods has been accepted as the common standard by the international soil community; such would provide the basis for method validation between laboratories with their actual/adjusted method.
Original languageEnglish
PublisherISRIC
Number of pages46
DOIs
Publication statusPublished - 15 Oct 2023

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