=Paper=
{{Paper
|id=Vol-3286/10_paper
|storemode=property
|title=Toward a Semantic Representation of Geoheritage (short paper)
|pdfUrl=https://ceur-ws.org/Vol-3286/10_paper.pdf
|volume=Vol-3286
|authors=Alizia Mantovani,Vincenzo Lombardo
|dblpUrl=https://dblp.org/rec/conf/aiia/MantovaniL22
}}
==Toward a Semantic Representation of Geoheritage (short paper)==
https://ceur-ws.org/Vol-3286/10_paper.pdf
Toward a semantic representation of geoheritage (short paper)
Alizia Mantovani1 and Vincenzo Lombardo1
1
University of Turin, Computer Science Department, Italy
Abstract
In this paper we address the semantic representation of the geoheritage. In literature,
geoheritage is defined as those elements of geodiversity that are outstanding for their
value/importance for humanity. It is part of the UNESCO heritage, included in the point
concerning the cultural aspect of natural features. The issue addressed in this paper is that the
concept of value and the lists of values are quite an open question: the concept of value is given
for granted in the geoheritage literature, and the lists of values are proposed in multiple
versions, by multiple authors in multiple application fields. The result is the incoherence in the
assessment of what is and what is not an element of geoheritage. In this paper we explore the
issue, presenting how a semantic approach may be an opportunity to reduce the level of
incoherence in the representation of the concept of geoheritage.
Keywords 1
Geoheritage, Geodiversity, semantics, ontology
1. Introduction
Our planet has a very rich ecosystem, based on the existence of many different living forms
(biodiversity), but also of non-living forms (geodiversity). The latter category, essential for the
existence of the first, encompasses all the geological formations, landforms and processes that are our
natural environment. Some of these geological elements are very relevant for the life on the planet and
the human society, considering both the supply and the cultural aspects, respectively. The cultural
aspects are summed up into the notion of geological heritage, or geoheritage. In literature, geoheritage
is defined by Sharples as “those elements of natural geodiversity which are of significant value to
humans for non-depleting purposes which do not decrease their intrinsic or ecological values” [1, p.11].
From this definition, we can extract two claims: first, the elements of the geoheritage are part of a wider
group of elements, i.e., the elements of geodiversity; second, what distinguishes a “regular” element of
geodiversity from an element that is worth considering geoheritage is that it has a particular importance,
or value for the humankind.
However, Sharples’ definition is only one of the many definitions in the literature, though the
concepts of geodiversity and value, respectively, are mostly recurrent. This paper explores these two
concepts and addresses a possible formalization. The aim is to reach a clarification about some core
aspects of the definitions, improving comparability and, possibly, consensus. Our starting point is the
definition of values. In fact, in literature, there are several lists of values to support the definition of the
geoheritage: a few values are common to all the lists, some values are partially shared, other values are
not shared at all. This aspect is clearly problematic: in acknowledging an element of geodiversity as an
element of geoheritage, we typically assign one specific value to that element, but what if that specific
value is not shared by all the definitions? For example, the Recreational value is one of the values that
is only partially shared: some authors consider acceptable a geological item that is relevant, e.g., for its
Proceedings Name, November, 2022, Turin, Italy
EMAIL: alizia.mantovani@unito.it (A. 1); vincenzo.lombardo@unito.it (A. 2)
ORCID: 0000-0001-5111-4882 (A. 1); 0000-0002-8166-9827 (A. 2)
© 2022 Copyright for this paper by its authors.
Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0).
1st Italian Workshop on Artificial Intelligence for Cultural Heritage (AI4CH22), co-located with the 21st International Conference of the Italian Association for Artificial
Intelligence (AIxIA 2022). 28 November 2022, Udine, Italy
capacity of attracting tourists, others do not consider it as a valid criterion for the assessment of
geoheritage.
Another problematic issue is the attribution of the value, i.e., what are the conditions to satisfy for
the attribution of a value to some item? Going back to the example cited above, is the capacity of
attracting tourists a valid and shared criterion for the attribution of the Recreational value? From this
point of view, and, considering that geoheritage is built on geodiversity, we aim to explore the
possibility to connect the values of geoheritage to the geosystem services, which can be recognized as
the goods and functions associated with geodiversity [2].
These are the issues explored in this paper, addressing their semantic representation to reduce the
level of subjectivity in the definition of the elements of the geoheritage. In the next sections, we will
explore the values of the geoheritage and of the geosystem services, respectively, and how they can be
related. A key for addressing this relationship comes from the analysis of the concept of value, deepened
by Perry [3], through the notion of interest.
The paper is structured as follows. In section 2, we review the concept of value and the values of the
geoheritage and the geodiversity, respectively. In section 3, we illustrate the first steps of the connection
of values and services, followed by some formal representation. In section 4 we provide an example.
Finally, section 5 provides some conclusions and future steps.
2. State of the art
As introduced before, the knowledge of the concept of geoheritage is dependent on two main
knowledge domains: the knowledge on the values that characterize the geoheritage and the knowledge
about the geodiversity and geosystem services, as geoheritage is built on the geodiversity. In this section
we analyze these domains, to access further analysis.
2.1. The values of geoheritage
The assessment of an element of the geoheritage is strictly dependent from the attribution of one or
more value to that element. Despite the variety of definitions present in literature, the relation of the
elements of geoheritage to the concept of value is widely acknowledged. What is not shared, vice versa,
are the individual values that contribution to the assessment. For our study, we selected four lists of
values, published in different scopes and for different goals. The lists are from Sharples [1] and Brilha
[4], for what concerns a theoretical and more “academic” approach, and from Georgousis et al [5] and
the US National Park Service (NPS) [6], for what concerns a non-specialized public (such as, e.g.,
students and tourists). The variety of goals provides us a wide range of points of view about the
assessment of geoheritage.
The major difference concerns the values that are listed in the several approaches. As it is possible
to see in Figure 1, not all the values are shared by all the authors. In fact, only Aesthetic, Cultural,
Educational and Scientific values are in common, while the others are shared by 3 to 1 list. For instance,
the Economic value, for elements that are a resource for some area (such as, e.g., a mineral resource or
a touristic resort) is listed by all the authors except Sharples. The consequence is that an element with
this kind of value would be considered geoheritage by Brilha, Georgousis and the NPS, but not by
Sharples. Moreover, some other issues arise for the Economic value: in fact, the meaning associated to
the value are actually two, that is, the existence, in some area, of a natural resource that is directly
involved in the economy of the area (e.g., a mine), and the consequences of tourism in some area (e.g.,
hotels, museums, restaurants, are sources of earning for the local population), respectively. Hence, this
causes a different assessment of geoheritage if we apply different lists to the same item. E.g., Brilha [4]
presents as an example of the Economic value the Escondida mine, a very important copper mine in
Chile, which makes the country the number one exporter of copper in the world. This site has a
relevance that fits with the first of the two meanings of the value, which is encompassed by Brilha and
NPS [6]. Vice versa, Georgousis et al [5] see differently this value, then this site is not geoheritage
following their criteria (as well as of Sharples, who doesn’t even have that value).
In this paper, we address the systematization of the lists through a semantic approach that can
encompass all the information provided by the several accounts mentioned above.
Sharples Brilha Georgousis NPS
2002 2018 2021
Aesthetic YES YES YES YES
Cultural YES YES YES YES
Educational YES YES YES YES
Scientific YES YES YES YES
Ecological YES NO YES YES
Economic NO YES YES YES
Intrinsic YES YES NO NO
Recreational YES NO NO YES
Artistic NO NO NO YES
Functional NO YES NO NO
Figure 1: Comparison of the lists of values. In green the values shared by all the lists, yellow values in
three lists, blue two lists, purple one list [1,4,5,6].
2.2. The concept of value, a philosophical question
Before the formulation of a semantic approach, we must clarify the concept of value itself: this is a
very old question, explored in several literature domains. Here we address the definition provided by
Perry [3], who proposes an approach based on the interests that contribute the assessment of some
value. In fact, the question that the author explores concerns how the value forms and how it can be
satisfied. His answer leans on the idea that a value is the fulfilment of one or multiple interests, which
are subjective, i.e., dependent on some individual or community perspective. So, it is paramount to
define at least one interest that an item can have to possess a value. For example, “Recreational value”
may have many different interests, based on what people likes to do in their free time. For example,
some people like to sunbath on the beaches in their free time, so a place like Algarve, Portugal, has an
interest for those people (interest that satisfies the Recreational Value). Differently, some people like
to climb in their free time, so climb is another interest for the Recreational Value. Moreover, the interest
of climbing is multiple: different places are important as climbing site of different types. El Capitan,
Yosemite National Park, USA, is famous for the numerous (more than seventy) thousand-meter-long
multi-pitch climbing routes (climbing with ropes, quick draw, and other equipment) while
Fontainebleau, France, is well known for the bouldering activity (climbing of few-meter-high boulders,
with no equipment except for crash pads and climbing shoes). A different example concerns the
Educational value: the goal of an high school teacher can be instructing the young students in general
concept about nature and geosciences, as well as for “Sunday tourists”, so a glaciological path like the
one in Alagna Valsesia, Sesia Val Grande UNESCO Global Geopark, Italy, is perfect to show to a non-
specialized audience (e.g., undergraduate students, or tourists) the traces of the glacial processes. Vice
versa, outcrops like the one in Zumaya, Spain, famous in the geological world for the presence of the
GSSP (Global Stratigraphic Section and Point) marking the limit between Selandian and Thanetian,
two stages of the Geologic Time Scale, part of the Paleocene Age, can be useful for the instruction of
the geoscience students, who are learning about stratigraphy.
Since interests are multiple and subjective, there can be many different interests based on the
individual/community needs and/or points of view: and this is not an easy task. Let’s however focus on
which are the interests of the human society for the elements of geoheritage.
As anticipated in the introduction of the paper, one of the common points concerning geoheritage is
the fact that every element of geoheritage is built upon an element of geodiversity. Hence, we can
explore the relevant characteristics of the elements of geodiversity to identify possible sets of interest.
A possible way, hence, is to explore the geosystem services, which are the benefits that the humankind
has from the existence of geodiversity. In the next section, we will deepen the topic, focusing on the
possibility to identify possible interests for the values of geoheritage.
2.3. Geodiversity and geosystem services
Geodiversity can be defined as “the natural range (diversity) of geological (rocks, minerals, fossils),
geomorphological (landform, physical processes) and soil features. It includes their assemblages,
relationships, properties, interpretations, and systems” [7].
Geodiversity makes our planet a house for many forms of life and provides the human society with
many resources for its wellness and development. All these benefits are represented with the geosystem
services paradigm, which is the abiotic correspondent of the Ecosystem Services, namely the goods and
functions of the ecosystems that society benefits of [8]. The geosystem services are inspired by the
ecosystem services and represent the benefits that the diversity of our planet brings to the environment,
to the life on earth, for the human society wellness and development. In the central part of Figure 2, we
represent the geosystem services: they are grouped into five categories, two concerning the processes
and the involvement in the use of the land by humans and other forms of life (marked as 1 and 2 in the
picture), one concerning the materials that humans use for feed and live (marked as 3), other two
concerning the intellectual part of the human society (culture and knowledge, 4 and 5 respectively).
Geodiversity plays a role essential in the existence of the services: for example, in our planet there
is diversity of soils, altitudes and climates, that are the reason for such a diversity in animals and plants,
hence food. Different vine plants grow in different geographical areas, and this has the consequence of
the existence of different wines, such as Brunello, from Montalcino area, Negramaro, from Salento
region, or Barbera, from Monferrato region.
3. Toward a semantic approach to the definition of geoheritage
To provide a semantic approach to the definitions of the values of the geoheritage, built upon the
geosystem services, we proceed through a formal alignment of the definitions, starting from different
lists of values. We go through a convergence of the meanings associated with the values enlisted for
the geoheritage and the geosystem services, respectively. First, we have carried out bibliographic
research, to collect all the information about the values and the services (namely, definitions and/or
examples and explanation); then, we have analyzed the lexicon used for the naming of the systems and
the values, respectively. Finally, we have designed a semantic representation from these findings.
Figure 2 represents a mapping between the values and the geosystem services (one value can be
connected to one or more services; vice versa, not necessary the services are connected to a value). In
the central part of the pictures there are the geosystem services [9], while on the lateral sections there
are some squares with the values, identified with different colors, plus some keywords extracted from
the definitions of the values. The arrows connect the whole value or singular keywords to the services.
This mapping is the result of a comparison between the definitions of the values and the examples
reported in the literature for the corresponding services, as they appear in the corresponding articles.
For example, the Ecological value, that appears in Sharples’, Georgousis’ and NPS’s lists, can be
assigned to those elements of geodiversity that have an essential role in the maintenance of the natural
ecosystem processes. For example, in the geosystem services, this is instantiated in some types of
processes, like the oceanic processes: the oceanic currents have an essential role in the climate
dynamics.
However, these associations are subjective, made on some informal association between the
perceived meanings attributed across the papers. To overcome such subjectivity and build sound
relationships, we have then carried out a lexicographic study, to verify the associations between terms
and possibly search for other relationships.
The idea has been to check the lexical relationships between the terms used for the geosystem
services and for the values of geoheritage, respectively. This was made through the Wordnet resource
[10]. This online resource provides, for an entered word, all its synset, with the definition of the word
in the context and the listing of related words (such as synonyms, hypernyms, and hyponyms). We
analyzed each term used for the services and for the values, respectively, and looked for the
correspondences. For the analysis, we started from the list of geosystem services, and analyzed one by
one all the terms, willing to find some association with the values or, at least, the keywords extracted
from the definitions of the values.
Unfortunately, this brough no results, there are no lexical correspondences between the list of
services and the values of geoheritage, even if many concepts are very similar for a human reader.
An example of expected “easy” association was between the Recreational value and its keywords
(tourism and recreation) and “Geotourism and leisure”. Except for tourism and geotourism, which have
the same root, no correspondence has been found with leisure; in fact, except for the words that are re-
used (like tourism), no associations were possible. A similar work of lexical comparison was between
the list of services of Figure 2 [9] and the one proposed by Webber et al [11]. In this case, some
associations were successful, for example between “Environmental quality” [9] and “Better living
surroundings” [11]: in fact, environment and surroundings are marked as part of the same synset.
Figure 2: Association between values of geoheritage and geosystem services [9]
Hence, in Figure 2 there is a comprehensive representation of the alignments which are possible in
this moment; as discussed above, they are mostly based on the bibliographic research, more than the
lexical study, which brough few tangible results. The lack of some lexicographic relationship between
the elements in the value lists leads to the necessity of the definition of the values in terms of low-level
features, namely the notion of interest mentioned above. Perry describes the value as consisting “in the
fulfilment of bias or interest. An object would be said to possess value in so far as it fulfilled interest or
assumed the relation of fulfilment to the term interest, where fulfilment is used in a generalized sense
for the consummation of either liking or disliking” [3, p.150].
At the current stage of development, we have outlined the semantic representation of the geoheritage
elements through a UML schema and a prototype of ontology, that connects the notions of geoheritage
and geodiversity, respectively.
After this overview of the knowledge domains of geoheritage and geodiversity, we can conclude
that by one hand, they are very rich in information, and by the other, this information presents a high
level of vagueness and ambiguity. In particular,
the existence of many lists of values that contain terms that are only partially shared and without
a clear, unambiguous definition of the terms listed
the possible differences in the definitions of the values, as resulted from the informal analysis,
mostly concerning the Economic value.
Figure 3 sketches the overall design of the ontological concepts. In the green-background area, there
is the part concerning geoheritage and geodiversity. Geoheritage is a subclass of geodiversity, which
are geological items. Both are described by CodeLists, which are vocabularies coming from the domain
knowledge. For example, a CodeList is a list of “relator” terms, associated to definition and relation
with other agents [12]. The geological items that are which compose the geodiversity is well described
in the OntoGeonous ontology, an ontology for the geosciences [13,14,15,16,17]. A geodiversity
element, then, can be either a physical element, such as the Geologic Unit (a body of earth material with
precise physical boundaries [18]), the Geomorphologic Feature (feature describing the shape and nature
of the Earth's land surface [18]), but also non-concrete features such as their relations, represented, e.g.,
by the Geologic Structure (a configuration of matter in the Earth based on describable inhomogeneity,
pattern, or fracture in an earth material [18]).
In the green part of the picture there are also the CodeLists describing the GeodiversityElement
class, and the one for the Geoheritage class. They are the services and the values, respectively. To be
part of the Geoheritage class, an item must be an element of geodiversity (must belong to the
GeodiversityElement class) and be associated to one or more Value from the CodeList.
GeodiversityElement, vice versa, can have (please note “can”, it is not a mandatory condition) a relation
with the CodeList Service.
Figure 3: Representation of the main structure of the OntoGeonous ontology [13,14,15,16,17], on
white background, connection with geodiversity and geoheritage in green background
The compilation of the CodeLists is a work in progress process. This is because of the value-interest-
service connection that we aim to pursue, following the theory by Perry [3]: hence, there will be an
additional part to this schema, collecting the interests, based on the services, that will be the base for
the attribution of the value to a given element of GeodiversityElement class, allowing it to be included
in its Geoheritage subclass. For example, the climbing activity, cited in section 2.2, can be an interest
for the Recreational value. Our final goal is to encode similar connections, to better describe the values
of geoheritage. We are basing the encoding of new concepts on the pre-existing encoded knowledge
about geosciences, in the OntoGeonous ontology [13,14,15,16,17]. Moreover, this ontology has already
been applied to the geological mapping process [19], which gives a ready method for the spatial
description of the elements that are geoheritage (with useful consequences for institutions such as, e.g.,
geoparks).
4. Example: Yosemite National Park
To show how we intend to connect values and services through the interests, here we analyze an
example of a UNESCO heritage site, that encompass many of the described features. We will analyze
the Yosemite National Park, California, USA: with its altitude variation from 600 to 3997 meters, it is
rich in geological and geomorphological formations as well as a great variety of flora and fauna.
Moreover, it is the destination of many outdoor lovers, especially climbers, who wish to climb the
famous walls of El Capitan.
Let’s analyze the point brought by UNESCO for the park to be defined as a geoheritage element
[20]:
Criterion (vii): Yosemite has exceptional natural beauty, including five of the world's highest
waterfalls, a combination of granite domes and walls, deeply incised valleys, three groves of giant
sequoia, numerous alpine meadows, lakes, and a diversity of life zones.
Criterion (viii): Glacial action combined with the granitic bedrock has produced unique and
pronounced landform features including distinctive polished dome structures, as well as hanging
valleys, tarns, moraines, and U-shaped valleys. Granitic landforms such as Half Dome and the vertical
walls of El Capitan are classic distinctive reflections of geologic history. No other area portrays the
effects of glaciation on underlying granitic domes as well as Yosemite does.
The most salient points in this description are natural beauty, five outstanding waterfalls, best
showcasing in the world of the glacial action in the granitic rocks, giant sequoias, and diversity of life
zones (which likely refers to many habitats for plants and animals).
To provide an illustrative example, we address:
● Environmental quality, for the natural beauty of the area, among which the spectacularism of
the waterfalls
● Biodiversity and Habitat provisioning for the existence of the giant sequoia and many forms of
life, due to the high-altitude variation
● Earth history, as it is a perfect showcase of how the glacial erosion act in the granitic rocks: in
the area, the intense glacial activity caused the formation of many landforms which stands and
are highly representative
● moreover, Geotourism and leisure for the high number of visits for leisure or sport
The connection that we aim to underline is between the services cited above, seen as interests for
the example area, and the values of geoheritage that can be, consequently, associated to the area. In this
case, these services can be connected to the:
● Aesthetic value, typical of areas with wonderful landscapes
● Ecological value, for the areas that are involved in natural processes and protection of natural
species and equilibrium of the ecosystem
● Scientific value, for what concern elements that are important for the reconstruction of the
history of the earth
● Recreational value, because of the touristic frequentation
With this example, we want to demonstrate that to the same area, on the same description, we can
apply the geoheritage value association, as well as the geosystem services classification. However, they
are both the associations based on some specific conditions or elements of the park: these are the
interests. It is a specific case of the Yosemite Park, the existence of the groves of giant sequoia, or the
presence of the El Capitan climbing wall. These are interests of habitat provisioning and geotourism
and leisure respectively. Our goal is to identify exhaustive lists of these interests and assess a formal
relation between values, services, and interests. For example, the sequoias, are an interest for the
“Biodiversity and Habitat provisioning” service, that can be related to the Ecological value, because of
the importance of the existence of the sequoias for the global diversity in the flora.
5. Conclusions and expected solutions
In this paper, we have described the problem of the definition of the geoheritage elements, and we
have addressed how a sound approach can be built on a semantic approach that connects geoheritage
elements and geosystem services.
We aim to develop a thorough representation of the geosystem services and of the values till getting
to a formal representation through UML, and then through an ontological representation. With respect
to our ontology design, we aim at introducing the additional class of the interests, which will be in
relation with both values and services. In fact, a deep analysis of the geosystem services can provide
the categories for the interests, and the formalized description will connect with coherence the values
to the elements that might be or not geoheritage. A description organized like this would also respond
to the first issue explained at the beginning of the paper, i.e., the informal assignment of the title of
geoheritage to some feature: in fact, an element can be described in the system and go into some
geoheritage class (one or more) based on the values that it gets from the interests. In this way, we aim
at preserving most information referred to by the experts, each considered feature would have its set of
value-system-interest and be included (if worthy) into one or more classes of geoheritage.
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