The SmartSkeMa team at IfGI (University of Muenster) successfully submitted their sixth project deliverable, D3.6, titled Concept of extended LADM ontology. The deliverable report outlines how its4land’s SmartSkeMa system addresses the mismatch between informal, indigenous, or customary land tenure systems documented using custom Local Domain Models (LDM) and the Land Administration Domain Model (LADM). The solution reported in D3.6 specifies an extension of LADM through SmartSkeMa’s LDM-LADM adaptor model which translates three main types of information from concepts defined in an LDM into concepts of LADM (Figure 1 below):

  1. conceptual non-spatial information to model non-standard rights, restrictions, and responsibilities,
  2. qualitative spatial information as spatial references, and
  3. spatial artefacts, areas with underdetermined spatial boundaries.

Figure 1. Graphic representation of the LADM extension through the LDMs.

Why an Adaptor Model

Land tenure systems implementing the LADM international standard cannot directly handle non-standard land tenure information such as rights, restrictions or responsibilities which are dynamic, rely on additional conditions, or whose temporal aspect is not fixed. Standard land administration systems use parcels which are quantitatively defined with their boundaries as spatial reference, while data collected with sketch maps (as is the case for SmartSkeMa) relies on qualitative descriptions. Finally, standard land tenure systems cannot deal with land use rights referring to areas whose spatial extent is determined by the function, thus spatial boundaries cannot easily be determined (e.g. where grazing zones overlap or the extent of a wildlife migration corridor). The deliverable report details the technical implementation as well as the user interfaces implemented in SmartSkeMa to allow information from the standard (or official) and local (informal, indigenous, or customary) to be used together to obtain a richer land information (Figure 2 illustrates and example of an output displayed in SmartSkeMa).

Figure 2. Displaying non-standard land tenure relations as LADM concepts in SmartSkeMa.

Video recordings of SmartSkeMa in action can be viewed at

Download deliverable, D3.6, here: Concept of extended LADM ontology.