Geoscience Reference
In-Depth Information
It is indeed widely acknowledged to be the basis of a healthy economy, and hence
the pertinence of such topic.
Current worldwide property cadastral registries use 2D parcels to register own-
erships rights, limited rights, and public law restrictions on land. In most cases this
is sufficient to give clear information about the legal status of property units. But
in cases of multiple use of space, with stratified property rights in land, the tradi-
tional 2D cadastre is not, or only in a limited way, able to reflect the spatial infor-
mation about those rights in the third dimension. As a matter of fact, the growing
density of land use in urban context is consequently increasing situations of ver-
tical demarcation between property units. Thus, 3D cadastre has been attracting
researchers through out the world for nearly a decade now to better register and
spatially represent real world overlapping situations.
As far as Portugal is concerned, a centralised distributed cadastral manage-
ment system, which implements a 2D cadastral model, has been conceived: the
so-called SiNErGIC. Nevertheless, its technical implementation is far from being
concluded mainly because most of surveyed geospatial data, referring to coordi-
nated cadastre, is still being acquired in the field and processed. Moreover, from
several experiences across the world it is known beforehand that a 2D model has
limitations for it is not capable of modelling and handling very well complex 3D
situations.
Every standard is generic in nature. Thus, the recently approved international
standard ISO 19152 (November 1st, 2012) should be adapted to Portugal's
cadastral reality. The standard model has to be conveniently applied in order to
incorporate Portuguese Cadastral Law. The ultimate goal should be the imple-
mentation of a 3D cadastral model capable of handling the overall cadastral
reality in Portugal. Ideally, further agreements between many stakeholders—
ranging from governmental bodies, research centres, to commercial parties—
should be achieved to assure optimal operability of such a model. As a result of
such a nationwide agreement, a 3D national standard for large-scale topography
should be set up.
1.3 Aim and Objectives
In the light of the above, an investigation of 3D cadastre aspects appears to be
pertinent both in the context of the Portuguese real estate law as well as in its geo-
metrical side. The main aim of this research is to discuss the pertinence of such an
investigation and launch its bases. Some objectives of this paper were identified as
follows:
• To start with, the review of both some historical circumstances and current sta-
tus of the Portuguese property cadastre
• In order to illustrate the pertinence of a 3D cadastre approach, the identiication
of some instances where the current 2D cadastral model in Portugal is clearly
limited