Regulatory aspects
been formalized yet. Some regulatory boundaries concerning fishing activities can also be shown. But because of the limitations imposed by cartographic representation, and the choice of legibility to preserve maritime safety, it is advisable to retain only the jurisdictional information
relevant to the navigator. The Shom has started digitizing ali the data
at its disposal but their formats and current forms restrict operational
use. In many cases, only the boundaries are available, rather than the zones,
although the latter are essential in analysis work. The electronic version
of marine charts (ECDIS) is starting to be set up. A study concerning
marine reference product definition has been undertaken (Allain et al.,
1999a).
As a result of the limitations mentioned above, and of the different
role of these charts in national law, sea charts do not include the main
French administration data at sea. For the time being, there is no systematic production of these data in georeferenced form.
The description of these boundaries in textual form is still widely
dispersed, not updated sufficiently and some boundaries remain
ambiguous. The high and low watermarks are not available in digital
form or are inadequate.
Sea farming leases cartography, which was conducted in a sectoral manner
by using relative positionings, is in the process of being digitized. Data
about parcels are destined for restricted use. At present there is no plan
to disseminate marine culture zoning which is nevertheless of vital
importance in many applications. The digitizing of boundaries relative
to the sanitary classification of production zones is programmed.
Leisure activities imply very precise boundaries which are continually
changing. These limits are often defined m terms of distance and can
be implemented in the field (buoys...). They are not necessarily displayed on georeferenced documents. The administrative and regulatory
data also suffer from the general problems linked to data collected in
the marine environment which are often fragmented, incomplete,
incompatible and difficult to access (Info-Coast'99, summary report).
In sectoral management, the use of maps established on different scales
and projections, as well as imperfections in terms of positioning, were
accepted before. But today, as data integration in the form of functional
and coherent geographical entities can be incorporated within a GIS,
which cancels the limitations of cartographic representation and offers
very broad analytical possibilities, a much more rigorous approach is
necessary.
A logical analysis of the modalities of construction
of georeferenced entities
In order to evaluate the pitfalls and coherence problems as regards
jurisdictional boundaries and zones, it was necessary to examine more
closely the modalities of construction of georeferenced units by returning
to the legal texts which define them. The inventory took into consideration the boundaries, or the zones, designed for the application of
jurisdictional or regulatory measures (navigation, resource exploitation,
273
been formalized yet. Some regulatory boundaries concerning fishing activities can also be shown. But because of the limitations imposed by cartographic representation, and the choice of legibility to preserve maritime safety, it is advisable to retain only the jurisdictional information
relevant to the navigator. The Shom has started digitizing ali the data
at its disposal but their formats and current forms restrict operational
use. In many cases, only the boundaries are available, rather than the zones,
although the latter are essential in analysis work. The electronic version
of marine charts (ECDIS) is starting to be set up. A study concerning
marine reference product definition has been undertaken (Allain et al.,
1999a).
As a result of the limitations mentioned above, and of the different
role of these charts in national law, sea charts do not include the main
French administration data at sea. For the time being, there is no systematic production of these data in georeferenced form.
The description of these boundaries in textual form is still widely
dispersed, not updated sufficiently and some boundaries remain
ambiguous. The high and low watermarks are not available in digital
form or are inadequate.
Sea farming leases cartography, which was conducted in a sectoral manner
by using relative positionings, is in the process of being digitized. Data
about parcels are destined for restricted use. At present there is no plan
to disseminate marine culture zoning which is nevertheless of vital
importance in many applications. The digitizing of boundaries relative
to the sanitary classification of production zones is programmed.
Leisure activities imply very precise boundaries which are continually
changing. These limits are often defined m terms of distance and can
be implemented in the field (buoys...). They are not necessarily displayed on georeferenced documents. The administrative and regulatory
data also suffer from the general problems linked to data collected in
the marine environment which are often fragmented, incomplete,
incompatible and difficult to access (Info-Coast'99, summary report).
In sectoral management, the use of maps established on different scales
and projections, as well as imperfections in terms of positioning, were
accepted before. But today, as data integration in the form of functional
and coherent geographical entities can be incorporated within a GIS,
which cancels the limitations of cartographic representation and offers
very broad analytical possibilities, a much more rigorous approach is
necessary.
A logical analysis of the modalities of construction
of georeferenced entities
In order to evaluate the pitfalls and coherence problems as regards
jurisdictional boundaries and zones, it was necessary to examine more
closely the modalities of construction of georeferenced units by returning
to the legal texts which define them. The inventory took into consideration the boundaries, or the zones, designed for the application of
jurisdictional or regulatory measures (navigation, resource exploitation,
273