TDWG Standards Metadata

Title: Biodiversity Information Standards (TDWG) Standards Metadata

Date Version Issued: 2021-02-01

Date Created: 2017-10-10

Part of TDWG Standard: Not part of any standard

This version: http://rs.tdwg.org/index/2021-02-01

Latest version: http://rs.tdwg.org/index

Previous version: http://rs.tdwg.org/index/2020-02-03

Abstract: This repository contains the source CSV files containing the metadata necessary to generate human- and machine-readable representations of the various components of Biodiversity Information Standards (TDWG) standards in accordance with the TDWG Standards Documentation Specification). This document represents the human-readable representation of the TDWG Standards data catalog.

Contributors: Steve Baskauf (TDWG Technical Architecture Group, TDWG Audubon Core Maintenance Group, TDWG Darwin Core Maintenance Group)

Bibliographic citation: Biodiversity Information Standards. 2021. Biodiversity Information Standards (TDWG) Standards Metadata http://rs.tdwg.org/index

Table of Contents

1 Metadata model for TDWG standards
2 IRI patterns
2.1 Patterns for current resources in the standards hierarchy
2.2 Patterns for versions of resources in the standards hierarchy
3 About directories in this repository
3.1 Relationship of parts of this repository to the metadata model
3.2 Files contained in current resources directories
3.3 Files contained in versions directories
3.4 Retrieving machine readable metadata from the datasets
4 Relationships of directories to resources in the TDWG Standards model
4.1 Metadata about ratified TDWG Standards
4.2 Utility metadata not governed by TDWG Standards
4.3 Metadata about obsolete pre-standard versions of Darwin Core

1 Metadata model for TDWG standards

Fig. 1. TDWG Standards hierarchy model (image from Standards Documentation Standard GitHub repository)

The TDWG Standards Documentation Specification (http://www.tdwg.org/standards/147) defines a hierarchical model for components of TDWG Standards (Fig. 1). At the highest level (1st level) are Standards. All TDWG Standards are linked by virtue of a common publisher relationship with TDWG itself. Documents and Vocabularies (2nd level) are the parts of Standards. Vocabularies are composed of Term Lists (3rd level), which correspond roughly to namespaces that define sets of terms. The Term Lists are composed of Terms (4th level), which may be Properties, Classes, or Concepts.

Each of the levels in the standards hierarchy are linked to the level above by a isPartOf relationsip, and to the level below by a hasPart relationship.

Fig. 2. Version model used to describe standards-related resources (image from the Standards Documentation Specification)

Any resource in the hierarchy above can be considered to consist of an abstract resource that persists over time, referred to as a "current resource". In Fig. 2, the arrow represents a current resource named ex:resource. A current resource has a creation date, and a last modified date.

The state of current resources over time is documented by versions of that resource. The versions are "snapshots" of the resource at a particular instant in time. In Fig. 2, the vertical lines represent versions - for example the version named ex:resource-2009-07-18.

The state of most properties of a current resource at the present time are shared by the most recent version of that resource. The properties of a current resource may change when a new version is issued. The issued date of the new version becomes the modified date of the current resource.

A current resource is related to each of its versions by a hasVersion relationship. A version of a resource is related to its current resource by an isVersionOf relationship. A version is related to a previous version by a replaces relationship and to a subsequent version by an isReplacedBy relationship.

2 IRI patterns

2.1 Patterns for current resources in the standards hierarchy

The IRI denoting Biodiversity Information Standards (TDWG) as an organization is:

https://www.grid.ac/institutes/grid.480498.9

1st level: IRIs denoting TDWG standards

are in the form:

http://www.tdwg.org/standards/nnn

where "nnn" is a number unique to a particular standard. Example for the Darwin Core Standard:

http://www.tdwg.org/standards/450

2nd level: IRIs denoting vocabularies

are in the form:

http://rs.tdwg.org/vvv/

where "vvv" is a string unique to the vocabulary. For example, "dwc" is the string for the basic Darwin Core vocabulary and "ac" is the string for the Audubon Core vocabulary. Example for the Darwin Core basic vocabulary:

http://rs.tdwg.org/dwc/

2nd level: IRIs denoting standards documents

are in the form:

http://rs.tdwg.org/sss/doc/docname/

where "sss" is a sequence of alphabetic characters representing the standard and "docname" is a short series of alphabetic characters representing the doucment. IRI examples are:

http://rs.tdwg.org/ac/doc/structure/

for the Audubon Core Structure document and

http://rs.tdwg.org/pnbd/doc/specification/

for the specification document of the Plant Names in Botanical Databases standard.

Some Darwin Core documents have legacy IRIs that do not follow this IRI pattern.

3rd level IRIs denoting term lists

are in the form:

http://rs.tdwg.org/vvv/sss/

where "sss" is a string representing the term list that is unique within vocabulary "vvv". IRI examples are:

http://rs.tdwg.org/dwc/iri/

for Darwin Core IRI-value Terms and

http://rs.tdwg.org/ac/terms/

for terms defined by Audubon Core.

4th level IRIs denoting vocabulary terms

are in the form:

http://rs.tdwg.org/vvv/sss/ttt

where "ttt" is the local name of a term defined as part of the term list http://rs.tdwg.org/vvv/sss/. IRI examples are:

http://rs.tdwg.org/dwc/iri/recordedBy
http://rs.tdwg.org/dwc/ac/caption

Term IRIs are not followed by a trailing forward slash. The "namespace" corresponding to the defining term list can be abbreviated to form a compact IRI (CURIE). Since dwciri: abbreviates http://rs.tdwg.org/dwc/iri/ and ac: abbreviates http://rs.tdwg.org/dwc/ac/, the two term IRIs given as examples above can be expressed as the CURIEs dwciri:recordedBy and ac:caption.

2.2 Patterns for versions of resources in the standards hierarchy

1st level: Standards

A standard with IRI in the form

http://www.tdwg.org/standards/nnn

has versions with IRIs in the form

http://www.tdwg.org/standards/nnn/version/yyyy-mm-dd

where yyyy-mm-dd represents the issued date of the version, using the lexical space of an XML schema date datatype (without timezone indicator). Example for the Darwin Core Standard:

http://www.tdwg.org/standards/450/version/2015-03-27

2nd level: Vocabularies

A vocabulary with IRI in the form

http://rs.tdwg.org/vvv/

has versions with IRIs in the form

http://rs.tdwg.org/version/vvv/yyyy-mm-dd

with yyyy-mm-dd as described for standards. Example for the Darwin Core basic vocabulary:

http://rs.tdwg.org/version/dwc/2014-12-23

2nd level: Standards Documents

A document in the form:

http://rs.tdwg.org/sss/doc/docname/

has version IRIs in the form

http://rs.tdwg.org/sss/doc/docname/yyyy-mm-dd

with yyyy-mm-dd as described for standards. Example for the Standards Documentation Specification:

http://rs.tdwg.org/sds/doc/specification/2017-04-25

3rd level: Term Lists

A term list with IRI in the form

http://rs.tdwg.org/vvv/sss/

has versions with IRIs in the form

http://rs.tdwg.org/vvv/version/sss/yyyy-mm-dd

Example for the Darwin Core IRI-value term list:

http://rs.tdwg.org/dwc/version/iri/2015-03-27

4th level: Terms

A term with IRI in the form

http://rs.tdwg.org/vvv/sss/ttt

has versions with IRIs in the form

http://rs.tdwg.org/vvv/sss/version/ttt-yyyy-mm-dd

Example for a version of dwciri:recordedBy:

http://rs.tdwg.org/dwc/iri/version/recordedBy-2015-03-27

3 About directories in this repository

3.1 Relationship of parts of this repository to the metadata model

Each directory in this repository contain metadata for a group of resources at some level in the hierarchy. The data described in each directory can be considered a dcat:dataset as described by the W3C Data Catalog Vocabulary (DCAT).

Directories whose names do not end in "-versions" contain metadata about current resources. Directory names ending in "-versions" contain metadata for versions of the current resources described in the corresponding folders that do not end in "-versions".

3.2 Files contained in current resources directories

Within each current resource directory there is a file whose name corresponds to the containing directory, plus the ".csv" file extension. That file contains the primary metadata about the resources described in that folder. For example, in the terms directory, the file terms.csv is the primary metadata file. The corresponding file with name ending in "-column-mappings.csv" maps the columns in the primary metadata file to standard metadata properties (similar in function to the meta.xml file of a Darwin Core Archive). Example: terms-column-mappings.csv.

The current resource directory also contains two files that contain link tables that describe one-to-many relationships between the current resource and related resources. The file with name ending in "-replacements.csv" (example: terms-replacements.csv) links current resources to other current resources that replace them. The file with name ending in "-versions.csv" (example: terms-versions.csv) links versions to their corresponding current term.

There are other files in each directory that contain configuration information or other information necessary to generate the machine readable metadata for the resources described in that directory.

3.3 Files contained in versions directories

Within each folder describing versions, the primary metadata is in the file whose name corresponds to the containing directory, plus the ".csv" file extension. For example, in the directory terms-versions, the file terms-versions.csv is the primary metadata file. The file with name ending in "-column-mappings.csv" (example: terms-versions-column-mappings.csv) maps the columns of the primary version metadata file to standard properties. The file with name ending in "-replacements.csv" (example: terms-versions-replacements.csv) is a link table that links versions to versions that replace them. Other files in the directory contain configuration or other information needed to generate machine readable metadata for the versions described in the directory.

3.4 Retrieving machine readable metadata from the datasets

The IRI http://rs.tdwg.org/index denotes the TDWG Data catalog. When dereferenced with an Accept: header of text/html, this document should be served. When dereferenced requesting text/turtle, application/rdf+xml, or application/ld+json, the data catalog should be served in the RDF/Turtle, RDF/XML, and JSON-LD machine-readable serializations respectively. (The machine-readable data catalogs can be retrieved using the explicit IRIs http://rs-test.tdwg.org/index.ttl, http://rs-test.tdwg.org/index.rdf, and http://rs-test.tdwg.org/index.json.) Note that as of 2020-02-03 the JSON-LD representation does not conform completely to the JSON-LD specification and should not be relied upon as a source of machine-readable metadata. It can, however, be consumed as generic JSON.

The links in the machine-readable metadata can be followed to determine a dcat:downloadURL to retrieve a dump of each of the datasets included in the data catalog. The set download URLs can be dereferenced to obtain the complete set of TDWG standards metadata. The general form of a dataset dumpa is

http://rs.tdwg.org/dump/datasetname

where "datasetname" is the name of the directory containing the dataset.

For more information, see this blog post.

4 Relationships of directories to resources in the TDWG Standards model

4.1 Metadata about ratified TDWG Standards

Level	Current resource IRI pattern	Directory	Version IRI pattern	Directory
Standard	http://www.tdwg.org/standards/nnn	standards	http://www.tdwg.org/standards/nnn/version/yyyy-mm-dd	standards-versions
Vocabulary	http://rs.tdwg.org/vvv/	vocabularies	http://rs.tdwg.org/version/vvv/yyyy-mm-dd	vocabularies-versions
Term List	http://rs.tdwg.org/vvv/sss/	term-lists	http://rs.tdwg.org/vvv/version/sss/yyyy-mm-dd	term-lists-versions
Document	http://rs.tdwg.org/sss/doc/docname/	docs	http://rs.tdwg.org/sss/doc/docname/yyyy-mm-dd	docs-versions
Document contributor roles	machine-readable links to contributors	docs-roles	N/A	N/A
Literal-value Darwin Core terms	http://rs.tdwg.org/dwc/terms/ttt	terms	http://rs.tdwg.org/dwc/terms/version/ttt-yyyy-mm-dd	terms-versions
Darwin Core IRI-value terms	http://rs.tdwg.org/dwc/iri/ttt	iri	http://rs.tdwg.org/dwc/iri/version/ttt-yyyy-mm-dd	iri-versions
dc: terms borrowed by Darwin Core	http://purl.org/dc/elements/1.1/ttt	dc-for-dwc	http://dublincore.org/usage/terms/history/#ttt-nnn	dc-for-dwc-versions
dcterms: terms borrowed by Darwin Core	http://purl.org/dc/terms/ttt	dcterms-for-dwc	http://dublincore.org/usage/terms/history/#ttt-nnn	dcterms-for-dwc-versions
Terms defined by Audubon Core	http://rs.tdwg.org/ac/terms/ttt	audubon	http://rs.tdwg.org/ac/terms/version/ttt-yyyy-mm-dd
dc: terms borrowed by Audubon Core	http://purl.org/dc/elements/1.1/ttt	dc-for-ac	http://dublincore.org/usage/terms/history/#ttt-nnn	dc-for-ac-versions
dcterms: terms borrowed by Audubon Core	http://purl.org/dc/terms/ttt	dcterms-for-ac	http://dublincore.org/usage/terms/history/#ttt-nnn	dcterms-for-ac-versions
Darwin Core terms borrowed by Audubon Core	http://rs.tdwg.org/dwc/terms/ttt	dwc-for-ac	http://rs.tdwg.org/dwc/terms/version/ttt-yyyy-mm-dd	dwc-for-ac-versions
EXIF terms borrowed by Audubon Core	http://ns.adobe.com/exif/1.0/ttt	exif-for-ac	versions not fully supported	dwc-for-ac-versions
IPTC terms borrowed by Audubon Core	http://iptc.org/std/Iptc4xmpExt/2008-02-29/ttt	Iptc4xmpExt-for-ac	versions not fully supported	Iptc4xmpExt-for-ac-versions
Music Ontology terms borrowed by Audubon Core	http://purl.org/ontology/mo/ttt	mo-for-ac	versions not fully supported	mo-for-ac-versions
photoshop terms borrowed by Audubon Core	http://ns.adobe.com/photoshop/1.0/ttt	photoshop-for-ac	versions not fully supported	photoshop-for-ac-versions
XMP terms borrowed by Audubon Core	http://ns.adobe.com/xap/1.0/ttt	xmp-for-ac	versions not fully supported	xmp-for-ac-versions
XMP rights terms borrowed by Audubon Core	http://ns.adobe.com/xap/1.0/rights/ttt	xmpRights-for-ac	versions not fully supported	xmpRights-for-ac-versions

4.2 Utility metadata not governed by TDWG Standards

Level	Current resource IRI pattern	Directory	Version IRI pattern	Directory
TDWG utility (dwcutility:) terms	http://rs.tdwg.org/dwc/terms/attributes/ttt	utility	http://rs.tdwg.org/dwc/terms/attributes/version/ttt-yyyy-mm-dd	utility-versions
Data catalog (DCAT) metadata	http://rs.tdwg.org/dump/datasetname	index	N/A	N/A
Executive decisions history	http://rs.tdwg.org/decisions/ttt	decisions*	N/A**	N/A
Darwin Core translations	multilingual labels (no IRIs)	dwc-translations	N/A	N/A

4.3 Metadata about obsolete pre-standard versions of Darwin Core

Level	Current resource IRI pattern	Directory	Version IRI pattern	Directory
Curatorial terms	http://rs.tdwg.org/dwc/curatorial/ttt	curatorial	http://rs.tdwg.org/dwc/curatorial/version/ttt-yyyy-mm-dd	curatorial-versions
Core terms	http://rs.tdwg.org/dwc/dwcore/ttt	dwcore	http://rs.tdwg.org/dwc/dwcore/version/ttt-yyyy-mm-dd	dwcore-versions
Geospatial terms	http://rs.tdwg.org/dwc/geospatial/ttt	geospatial	http://rs.tdwg.org/dwc/geospatial/version/ttt-yyyy-mm-dd	geospatial-versions
Type terms	http://rs.tdwg.org/dwc/dwctype/ttt	dwctype	http://rs.tdwg.org/dwc/dwctype/version/ttt-yyyy-mm-dd	dwctype-versions
ZooArchNet chronometric age terms	http://zooarchnet.org/dwc/terms/ttt	chrono-zooarchnet	http://zooarchnet.org/dwc/terms/version/ttt-yyyy-mm-dd	chrono-zooarchnet-versions
terms not in the tdwg.org subdomain	various IRI forms	dwc-obsolete	various IRI forms	dwc-obsolete-versions

* The decisions directory also contains a CSV file that links vocabulary terms with the decisions that affected them.

** It does not seem necessary at the present time to maintain versions of the decisions themselves, although there are versions of the decisions list. This could be changed in the future if necessary.