The visible boundary: more than just a line between coordinates

Within land administration, boundaries of people’s land plots (or parcels) are a key component. From a legal-societal perspective, a boundary is where one person’s interests in land end and the next person’s interests begin. In most conventional contexts, this ‘surface’ is depicted by the infinitesimally thin line where this surface intersects the earth’s surface. This line is often manifested physically by visible artefacts like hedges, stone walls, ditches, or land use changes.
In 19th and early 20th centuries, during cadastral and land granting activities, simple surveying technologies were used (e.g. plane tables) and associated precisions available were accepted. Later, equipment became more advanced, and so did the accuracy with which the line could be determined. The question is whether the neighbours, and society, can – and should – bother indicating this line with an ever increasing precision. Whereas ground survey methods (incl. GNSS) have continued to be more and more precise, aerial and space based approaches also emerged: these cover large areas faster, but have not (yet) caught up in precision. In any case, visible boundary features are by default not infinitesimally thin.
The above issue manifests itself in the ‘coverage over accuracy’ debate. In several (first) land registration projects, like Thailand, St. Lucia and Rwanda, aerial images were successfully used. The approaches are said to support recording the ‘70% of the word’s land parcels that are not yet mapped’ and meet FIG and WB’s “fit-for-purpose land administration” ideals (FIG/WB, 201 (FIG/WB, 2014).
We argue that ‘visible’ boundaries actually fit the greater majority of land management and land information system purposes, perhaps with the exception of reconstructing boundaries between conflicting parties, and natural phenomena that we wish to apportion property rights (or protections) to, but are beyond human scales (e.g. migratory routes). An analysis of the societal and land right holder benefits is presented as a contribution to support ‘fit-for-purpose land administration’.