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Name Definition
Data Type Multiplicity
label Name of the taxon e.g. ‘Allophanic Soil’.
String One
scheme Reference to the soil taxonomy that defined the
taxon. SO_SoilTaxonomy
One
9.2.1.9 SO_HorizonDesignation
A term to categorize the soil horizon according to certain physical criteria. Horizons may be defined as genetic, morphological, functional or diagnostic horizons to support
differentiation of soils into soil taxa.
Name Definition
Data Type Multiplicity
label A soil horizon designation.
String One
scheme The scheme from which the designation value is
taken. To be determined
One
9.2.2 Soil Sampling and Observations
The sampling and observation model Figure 6 has been designed to make extensive use of the OGC Observations and Measurements model [ISO 19156:2011]. The
sampledFeature or featureOfInterest will be a SO_Soil or SO_Horizon as defined in this model. Domain specific classes have been added for informative purposes to show how
concepts describing the sampling strategy, many of them not unique to the soil domain, map on to the OM model. The OM abstract specification provides a full description
of the model.
9.2.2.1 SamplingFeature
OM defines a sampling feature SamplingFeature as a feature which is involved in making observations concerning a domain feature. EXAMPLE Station, transect, section
or specimen.’ They may be spatially constrained SpatialSamplingFeature when ‘observations are made to estimate properties of a geospatial feature, in particular where
the value of a property varies within the scope of the feature...‘. Specimens are ‘a physical sample, obtained for observations normally carried out ex-situ, sometimes in a
laboratory.’
Four informative sub-types of a SpatialSamplingFeature were defined to show how it encompasses common artefacts of soil sampling strategies: the soil survey SO_Survey,
site SO_Site, plot SO_Plot and a simple marker locating a sampling event SO_Station. An additional subtype SO_Layer was added for circumstances where an
arbitrary layer of the soil with some lateral extent is sampled. An explicit distinction is made between these sampling layers and a layer within the soil, which is defined by some
environmental process, or other character of the soil, but is not a soil horizon. This later concept has not been modelled but could be defined as per the MaterialLayer class in the
ISOIUSS ‘Wageningen Proposal’.
Copyright © 2016 Open Geospatial Consortium.
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Figure 6 — Soil sampling and observation class model
The SO_Sample class highlights that the common use of the term ‘sample’ within the soil community is equivalent to a Specimen in ISO19156:2011.
Two informative properties were defined for soil sampling features to reinforce their importance to a description: depth the location of the sampling feature relative to the top
of the soil; and representativePoint a point marker used to locate a sampling feature, which itself may have a greater or more complicated extent – captured by the shape
property. These properties are not unique to the soil domain.
