Introduction

This website presents a thesaurus for the domain of cadastre and land administration, CaLAThe. The domain regards the surveying and mapping of land, more specifically the boundaries of land parcels and individually owned buildings and building parts (condominiums), as performed by the profession of surveyors. From a public point of view, the domain provides the administrative and technical base for taxation of land and buildings, and for land use planning; from a private point of view, the domain supports security in ownership and other land-related rights. 

The domain of CaLAThe spans technical issues: surveying and mapping and geoinformatics, as well as social science issues, including law and public administration.  Limited consensus exist on core concepts [1] and in order to improve the scientific basis for domain research, this Cadastre and Land Administration Thesaurus (CaLAThe) was developed and issued 2011. The development benefitted from standardization efforts within the domain, detailed below. However, the standardization efforts so far addressed only parts of land information management, and from different perspectives: database maintenance vs update processes. Thus, as of 2021, CaLAThe serves as a mediating platform, which could support an alignment of the standards, and hence data interoperability [2].

Standardization within the construction domain developed differently from standardization within the geospatial domain. Research is aiming at the integration of Building Information Modelling (BIM) and Geographic Information Systems (GIS). Approaches include applying semantic web technology with intermediate data schema(s), which refer to a shared ontology. CaLAThe may facilitate the development of such ontology, and thereby support e-government initiatives, and more generally recurrent overhaul of existing information systems.

CaLAThe is a semantic resource, a controlled vocabulary, which follows the W3C SKOS recommendation and - where possible - employs URIs of concepts and links to other Linked Open Data sources. It is one of the many semantic resources recorded in the Basic Register of Thesauri, Ontologies & Classifications (BARTOC).

Emergence of domain terms

The term Cadastre may be related to Venetian (1185) catastico ("list of citizens possessing a taxable property"), which through 18th century French developments was adopted into English meaning 1. a public survey of land for the purpose of taxation, and 2. a register of such surveys, showing details of ownership and value. The term Land Administration appears in a 1973 Seminar on Land Administration in Kuala Lumpur, Malaysia [3]. The UN/ECE in 1996 published Land Administration Guidelines with special reference to countries in transition [4], and authors of a textbook on Land Information Management in 1999 issued a renewed version with the title Land Administration [5].

Scientific reflection of this domain resulted in 2002 in a proposal for the development of a standardized Cadastral Core Domain Model, based on the geographic standards from ISO and OpenGIS (from 2004: Open Geospatial Consortium, OGC) and to be developed in cooperation with the International Federation of Surveyors, FIG [6,7]. The proposal was through further developments finally approved as the ISO 19152:2012 Land Administration Domain Model (LADM). The draft LADM standard made the base for preparation of the initial version of CaLAThe, which was related also to existing thesauri, primarily the GEMET thesaurus, the  AGROVOC thesaurus, and the STW Thesaurus for Economics, and issued September 2011. Version 3 was supplemented with terms from the OGC Land and Infrastructure Conceptual Model Standard (LandInfra), and version 4 added selected code lists names and values from both standards. Version 5 added Danish and Turkish terms, and version 6 added Malay terms.

Content

CaLAThe comprises about 250 concepts; a growing number of these have been defined, where possible following the genus-differentia type of definition.Thesaurus content may be accessed through term search, through alphabetical listing, and through graphical overviews of thesaurus term relations, which are rendered in the main term collections: Activity, Information, Land, Law, Party, and Survey, respectively. Finally, the development of CaLAThe is detailed in version overviews.