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  <front>
    <journal-meta>
      <issn pub-type="ppub">1613-0073</issn>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>Towards Preserving Biodiversity using</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Albin Ahmeti</string-name>
          <email>albin.ahmeti@semantic-web.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Jan-Kees Schakel</string-name>
          <email>jankees.schakel@sensingclues.org</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Robert David</string-name>
          <email>robert.david@semantic-web.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Artem Revenko</string-name>
          <email>artem.revenko@semantic-web.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Semantic Web Company</institution>
          ,
          <country country="AT">Austria</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Sensing Clues Foundation</institution>
          ,
          <country country="NL">Netherlands</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Vienna University of Technology (TU Wien)</institution>
          ,
          <country country="AT">Austria</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Preserving biodiversity, encompassing species and their habitats, is gaining significant attention and becoming a central concern, alongside the focus on climate change. Climate change directly impacts biodiversity and is a prominent aspect of Environmental, Social, and Governance (ESG) criteria. At the EU level, designated areas called Natura 2000 sites have been established for protection and conservation, aimed at safeguarding habitats and species. However, the data regarding these sites, habitats, and species is currently dispersed and isolated, resulting in limited usefulness. To address this issue, we introduce our work on a Knowledge Graph (KG) for biodiversity, known as Nature First KG. This KG aims to connect various data silos, including information about sites, species, and habitats, through cross-references called crossovers. Combining it with a digital twin, we empower recommender use cases such as: preventing human-wildlife conflicts, facilitating species reproduction, and combating illegal poaching to name a few.</p>
      </abstract>
      <kwd-group>
        <kwd>knowledge graphs</kwd>
        <kwd>biodiversity</kwd>
        <kwd>data integration</kwd>
        <kwd>linked open data</kwd>
        <kwd>FAIR</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>CEUR
ceur-ws.org</p>
    </sec>
    <sec id="sec-2">
      <title>1. Introduction</title>
      <p>
        Climate change is one of the main challenges that has preoccupied mankind in the recent
decades. The efects of climate change have critically altered ecosystems and biodiversity all
around the world, changes in ecosystem range and distribution, ecosystem composition, local
species extinctions or mass mortality events of plants and animals have been observed [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ].
Human-induced land cover change has led to environmental impacts such as the decline of
biodiversity and other ecosystem services1. Similar negative results have been observed with
anthropogenic change of land use, i.e., replacing nature with architectural buildings for humans
to live in enclosed spaces, as reported in this survey [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. In order to tackle the issue – in the
broad level of climate change – the United Nations (UN) have identified a number of goals to be
achieved on the topic of Environmental, Social and Governance (ESG).
      </p>
      <p>Furthermore, at the European Union (EU) level, designated areas called Natura 2000 sites
CEUR
Workshop
Proceedings
have been established for protection and conservation, aimed at safeguarding habitats and
species. However, the data regarding these sites, habitats, and species is currently dispersed
and isolated, resulting in limited usefulness. Data is provided by diferent organizations and
classification systems such as EUNIS2 and IUCN 3 in diferent structure, format and completeness;
with IUCN reporting mainly on threatened species aka. “Red List Species.” The problem is
further exacerbated due to existence of diferent versions of habitat taxonomies alongside
habitat names and codes that have changed over time but in fact are equivalent, namely habitat
“Subarctic and alpine dwarf Salix scrub” with code S21 in EUNIS ver. 2021 versus “Subarctic and
alpine dwarf willow scrub” with code F2.1 in EUNIS ver. 2012. Domain experts have created
spreadsheets maintaining the relationships between habitats – describing how one habitat
maps to another using crossovers, i.e., if they are equivalent (=), superset (&gt;), subset (&lt;) or
overlap (#) to the designated habitats in other versions. Despite those eforts, the data is not
linked and contextualized to a larger context, and the semantics of such relations are only
known to those experts. In addition, the occurrences of species that are known to exist in
habitats are written using latin names as strings (Ursus arctos), without further connection
to the source of truth species URIs for looking up and dereferencing them as things (https:
//eunis.eea.europa.eu/species/1568). Similarly, data about sites have connections to habitats
and species, and are also of spatial form that are provided in shapefiles along with geometric
coordinates. This opens new challenges in terms of querying and performing geo-calculations
with polygons, in addition to having relations to habitats and species as triple patterns by using
GeoSPARQL. For a better presentation, we have summarised all the discussed problems and
challenges in Table 1.</p>
      <p>In this paper, we present our work towards a Knowledge Graph (KG) for biodiversity in
the context of Nature FIRST research project4—dubbed Nature FIRST KG—that connects
silos of data, namely sites, species and habitats by using cross-references, so-called crossovers.
The imported data is heterogeneous, ranging from shapefiles to tabular data, which are then
mapped, integrated and consolidated in a KG; afterwards the entities in KG are linked using
relations based on crossovers, constituting Linked Open Data (LOD). The crossover relations are
based on SKOS relations with well-defined meaning, namely for habitat mapping e x a c t M a t c h ,
b r o a d M a t c h , n a r r o w M a t c h , or c l o s e M a t c h ; in other cases we use a bespoke OWL (object) property
e.g., h a s D i a g n o s t i c S p e c i e s specifying indicator species for a habitat. The relation from a site to
a habitat also contains the coverage information in percentage that has motivated us to use the
RDF*5 (RDF-star) data model for representing the percentages in the relation itself in a compact
way akin to property graphs. We summarize our contributions:
• Provide a KG that semantically links disparate information, allowing to traverse and get
new insights powering new use cases pertaining to biodiversity;
• Methodology for creating relations from crossovers in KG;
• Publish and Consume KG using LOD frontends, graph view and SPARQL endpoint to
comply with FAIR principles.
2European Nature Information System of the European Environment Agency (EUNIS/EEA), https://eunis.eea.europa.
eu/
3The International Union for Conservation of Nature, https://www.iucn.org/
4https://www.naturefirst.info/
5https://www.w3.org/2021/12/rdf-star.html</p>
      <p>Problem</p>
      <p>Silo-ed data
Dataset versions
String occurrences</p>
      <p>Shape files
Natura 2000 sites</p>
      <p>Authority sources
EUNIS/EEA, IUCN habitats &amp; species</p>
      <p>EUNIS/EEA habitats
EUNIS/EEA sites, habitats, species</p>
      <p>EUNIS/EEA sites
EUNIS/EEA sites</p>
      <p>Challenges
completeness, mapping
mapping, semantics</p>
      <p>entity extraction
GeoSPARQL computations
reified statements</p>
    </sec>
    <sec id="sec-3">
      <title>2. Methodology</title>
      <p>The data ingested in the KG comprises of habitats, species and Natura 2000 sites. There are
various data authorities when it comes to habitat and species data, such as EUNIS and IUCN.
The data sources are in diferent formats, schemas and completeness (c.f. Table 2). In addition,
within EUNIS there exist diferent version of habitats (ver. 2017, 2021) that map to a legacy one
(ver. 2012). The requirement is to consolidate the data into a KG, with each version having a
crossover link to the source of truth or legacy version. The advantage of this approach is that one
can report data that is already described using a taxonomy by specifying another taxonomy that
is interlinked. Each version has its own description, codes and granularity in terms of broader
relationships in the SKOS hierarchy. It is worth mentioning that Red List Species contained the
taxonomic rank (S p e c i e s - &gt; G e n u s - &gt; F a m i l y - &gt; O r d e r - &gt; C l a s s - &gt; P h y l u m - &gt; K i n g d o m ), whereas EUNIS
only contained ‘genus’ as a parent relationship. In both cases, s k o s : b r o a d e r relationships were
created in order to create the hierarchy.</p>
      <p>
        As seen from Table 2, some of the data is already in RDF, while others are non-RDF and
need to be transformed using ETL (Extract-Transform-Load). For the transformation, we used
UnifiedViews [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] tool that is able to do transformation of tabular data (CSV, XLS) using respective
Data Processing Units (DPUs). Each DPU contains a logic where one can configure the mappings
of how each column is mapped to a property in the ontology. Regarding the shapefiles, we
used GeoTriples [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] application that generates RML6 mappings from the provided Natura2000
shapefiles 7. We can distinguish three cases when building crossovers:
• EUNIS vs IUCN habitats, species resp. by using the common labels (latin names);
• EUNIS habitats with links to diferent versions by using the expert spreadsheet 8,
which uses codes such as =, &lt;, &gt; and #; A SPARQL query generates s k o s : e x a c t M a t c h ,
s k o s : n a r r o w M a t c h , s k o s : b r o a d M a t c h and s k o s : c l o s e M a t c h after mappings are run;
• Species mentioned only in latin name that we apply concept annotation via NLP
techniques to determine their URI (EUNIS Species taxonomy), using relations such as
: h a s D o m i n a n t S p e c i e s , : h a s D i a g n o s t i c S p e c i e s , or : h a s C o n s t a n t S p e c i e s .
      </p>
      <p>
        Regarding URI management — by following the Linked Data principles [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] — we reused source
authority URIs, e.g., http://eunis.eea.europa.eu/habitats/409 and in cases where we ought to
      </p>
      <sec id="sec-3-1">
        <title>6https://rml.io/specs/rml/</title>
        <p>7https://www.eea.europa.eu/data-and-maps/data/natura-14/natura-2000-spatial-data
8https://www.eea.europa.eu/data-and-maps/data/eunis-habitat-classification/eunis-habitat-classification-review-2017
generate the URI, we made sure that it conforms to our Linked Data frontend so that it becomes
dereference-able, e.g., https://sensingclues.poolparty.biz/HabitatClassificationScheme/237.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>3. Nature FIRST KG</title>
      <p>In Table 2 is shown the current snapshot of Nature First KG. Per each project (taxonomy) are
given the stats such as the input data, number of total concepts, the crossovers with respect to
other projects, and the total number of relations with respect to other projects. The relations
are only materialized in direct relationships without storing the inverse relations - as also seen
from the ‘no value’ (-) for #1 EUNIS Species.</p>
      <p>No # Project (Taxonomy)
1 EUNIS Species
2 EUNIS Habitats 2012
3 EUNIS Habitats 2017
4 EUNIS Habitats 2021
5 Habitats Annex I
6 General habitats
7 IUCN Species
8 IUCN Habitats
9 Natura 2000
10 Corine Land Cover</p>
      <p>Input data</p>
      <p>RDF
RDF
XLS
XLS
XLS
XLS
RDF</p>
      <p>CSV
CSV, shapefile</p>
      <p>RDF</p>
      <p>The Linked Data frontend can be used to browse the projects and is accessible here9, whereas
the SPARQL endpoint for a specific project, e.g. for ‘EUNIS Habitats 2012’ can be accessed
here10. Moreover, the graph visualisation for all the projects is accessible using GraphViews
application11. The aforementioned URIs ensure that the approach complies with FAIR.</p>
      <p>We created explicit g e o n a m e s : n e a r b y relationships between Natura 2000 sites that in
addition have relations to EUNIS species and ‘General habitats’ via the ontological relationships
: s i t e H a s S p e c i e s and : s i t e H a s H a b i t a t resp. Moreover, the percentage coverage has been
included to specify the percentage of habitat that the site contains using RDF*. We provide such
a query in the following that combines n e a r b y relations and percentage of habitats in RDF*,
which computes the TOP 5 largest habitats that are close to : A T 1 1 0 1 1 1 2 area12.
PREFIX geonames : &lt; h t t p s : / / www. geonames . o r g / o n t o l o g y # &gt;
PREFIX s i t e : &lt; h t t p s : / / s e n s i n g c l u e s . p o o l p a r t y . b i z / S i t e O n t o l o g y / &gt;
PREFIX : &lt; h t t p s : / / s e n s i n g c l u e s . p o o l p a r t y . b i z / N a t u r a 2 0 0 0 S i t e / &gt;
SELECT ? l a b e l (SUM ( ? p e r c e n t a g e ) a s ?sum ) ( g r o u p _ c o n c a t ( ? p e r c e n t a g e ) a s ? c n t )
WHERE
{
: AT1101112 geonames : n e a r b y ? s i t e s .</p>
      <p>&lt;&lt;? s i t e s s i t e : s i t e H a s H a b i t a t ? l a b e l &gt;&gt; s i t e : p e r c e n t a g e C o v e r ? p e r c e n t a g e .</p>
      <sec id="sec-4-1">
        <title>9https://sensingclues.poolparty.biz/</title>
        <p>10https://sensingclues.poolparty.biz/PoolParty/sparql/Habitats
11https://sensingclues.poolparty.biz/GraphViews/
12https://sensingclues.poolparty.biz/PoolParty/sparql/Natura2000Site
}
g r o u p by ? l a b e l o r d e r by d e s c ( ? sum ) l i m i t 5</p>
        <p>
          Similarly, one can exploit : s i t e H a s S p e c i e s relations in order to build recommender systems
that can predict Ursus arctos movement in respect to sites, based on preferred habitats and
species. On top of this, one can use SPARQL query federation using SERVICE keyword in order
to query diferent SPARQL endpoints and join results based on common variables. This system
combined with a digital twin [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ] is useful as it provides observations and reasoning that can be
leveraged in order to prevent a human-wildlife conflict.
        </p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>4. Conclusions &amp; Future work</title>
      <p>
        We have created a first version of Nature FIRST KG that can be used to power diferent use cases
that pertain biodiversity, addressing the problems reported in Table 1. We plan to enrich our
KG and ingest new sources that are related to site conservation, threats, treatment actions and
plans. Similarly, we are planning to add Ecological Networks [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] as a backbone to our KG in order
to perform diferent reasoning tasks. This infrastructure will be used to build recommender
systems that predict the movement of Ursus arctos and other relevant species in the context of
Nature FIRST research project. We will also study related knowledge graphs on biodiversity
such as Ozymandias13 and relevant parts of Wikidata, in order to reuse, link and query those
KGs in conjunction with the Nature FIRST KG.
      </p>
    </sec>
    <sec id="sec-6">
      <title>Acknowledgments References</title>
      <p>We thank Boris Hinojo and Emil Zegers for their assistance and constructive feedback.</p>
    </sec>
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