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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Towards designing an ontology encompassing the environment-agriculture-food-diet-health knowledge spectrum for food system sustainability and resilience.</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Ruthie Musker</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Matthew Lange</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Allan Hollander</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Patrick Huber</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Nathaniel Springer</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Courtney Riggle</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>James F. Quinn</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Thomas P. Tomich.</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>University of California</institution>
          ,
          <addr-line>Davis Davis, California</addr-line>
          ,
          <country country="US">USA</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>- Feeding 9 billion people is not solely a matter of food, health, nutrition, and the environment. Promoting human health by increasing the sustainability and resilience of food systems requires integrating information from a broad range of disciplines from human nutrition/health systems and agricultural/natural systems to social, financial, physical and political systems. Ontologies serve to specify common terminologies for critical concepts and relationships within these systems, however very few ontologies have been developed with this interdisciplinary focus. Biological ontologies, whether focused on human physiology, soil quality, or nutritional value are only part of the story when it comes to determining linkages throughout the food system that help determine human health and wellbeing. We seek to build an ontology of food and food systems that encompasses the relevant sustainability issues in their entirety. We have already built an ontology of sustainable sourcing of agricultural raw materials issues and indicators, but aim to expand our ontology to include attributes of resilience, and other issues along the environment-agriculture-food-diet-health knowledge spectrum. Additionally, we aim to create this ontology with the intention of quick usability for the food system decisionmaker.</p>
      </abstract>
      <kwd-group>
        <kwd>food systems ontology development</kwd>
        <kwd>food system sustainability</kwd>
        <kwd>food system resilience</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>I. INTRODUCTION</title>
      <p>Ontologies are becoming increasing essential for synthetic
research and statistical analytics where data from one
scientific community is transformed through sequential
models (a scientific workflow) to address problems typically
posed by different communities accustomed to different
terminologies for overlapping concepts. Important early
efforts to formalize ontological frameworks include in
biomedicine (NIH, OBO), agriculture (AGROVOC), and
environmental biology (TDWG, NBII, GBIF), jointly
characterized by rich vocabularies for names of chemical
compounds, soils, species and varieties, and complex
interactions. However, despite wide agreement that
environmental quality is an important driver of sustainable
food systems, which in turn promote health, the ontological
efforts to date do not span the range of linked analyses
needed to research the indirect but powerful connections
that interact in these systems.</p>
      <p>While increased understanding of the linkages between
food, diet, sustainability and health offer solutions from
individual to global health improvement, optimization, and
maintenance; it would be shortsighted to decouple
knowledge and information about food and the food system
from the community that produces and utilizes it. Thus, our
research is divided into two components. The first is to
provide a practical, open access information platform that
will bring coherence to a comprehensive array of food and
health systems information. The second is to ensure that the
information platform will sufficiently serve the
environment-agriculture-food-diet-health system community
it is meant to benefit.</p>
      <p>By creating this ontology, we aim to help decision-makers
access reliable data and metadata, observe justifications of
relationships between concepts, and quickly see which other
actors are interested in similar issues. The end goal of our
ontology is three-fold:
1.
2.
3.</p>
    </sec>
    <sec id="sec-2">
      <title>Our ontology will provide decision-makers with</title>
      <p>access to data discovery and clearly show data
that applies to their region of interest, what
metadata exists, how to aggregate or disaggregate
available data, how interoperable the data are based
on data sources, etc.</p>
      <p>Our ontology will focus on conceptual linkages
among actors/concepts and the
justifications/validations for those conceptual
linkages. We believe that multiple linkages may
exist between two issues due to various contexts,
such as region, scale, commodity, and social
structure.</p>
    </sec>
    <sec id="sec-3">
      <title>Any framework covering this range of disciplines</title>
      <p>must have mechanisms to link to standardized
usages (e.g., the Linked Data universe) and have
mechanisms for cross-referencing identical or
closely related concepts in standard use by
different communities of practice.</p>
      <p>
        These goals will in a format that is flexible based on the end
users needs. This infrastructure, which supports
standardsbased loosely-coupled yet interoperable linked data will
collapse time to cross-disciplinary insight and discovery,
concomitantly accelerating food and health innovation.
Although recognition has been paid to creating an ontology
of sustainability, the Sustainable Development Goals
Interface Ontology (SDGIO), this ontology was built based
on an already established conceptualization of sustainability
goals, and rarely mentions “food” outside of “food
security”. Our approach builds from the inside-out,
understanding that inclusivity of information, concepts,
linkages, and data eliminates disciplinary boundaries and
allows all food system stakeholders the ability to help create
and use our ontology. Evidence shows that the “co-creation”
of transdisciplinary research can improve credibility,
relevance, and legitimacy, ultimately helping overcome
social, administrative, and political boundaries and, thereby,
improving chances for development of innovative strategies
with better prospects for successful implementation [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ][
        <xref ref-type="bibr" rid="ref2">2</xref>
        ].
      </p>
    </sec>
    <sec id="sec-4">
      <title>II. CURRENT ONTOLOGY</title>
      <p>
        The ontology proposal builds upon the work of Springer et
al. (2015) [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], and the conference paper of Musker et al.
(2015) [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. Foundational work at University of California,
Davis by the Agricultural Sustainability Institute and the
Information Center for the Environment screened
international sustainability assessments, livelihoods
assessments, and published food industry sustainability
policies to identify a comprehensive set of food system
sustainability issues and indicators, providing a starting
point for environmental and food production portions of a
food-and-health ontology. Springer et al. (2015) discuss the
development of an ontology to express the relationship
between environmental indicators, issues, conceptual
frameworks, and data and reference sources
(https://github.com/ICFOODS/asi_sustainability/blob/master/ontology/sustsource.
owl). This ontology contains classes for two conceptual
frameworks, four sets of sustainability capital groups, and
44 integrated issues and describes relationships between
indicators and issues using the SKOS schema.
      </p>
      <p>
        Another approach to our current ontology takes a DPSIR
framework approach [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] and determines structured linkage
relationships between the Drivers, Pressures, States, Impacts
and Responses (Figure 1). Each issue from Springer et al.
(2015) could be placed in one of these categorizations,
therefore creating a basic standardized ontology of the food
system at the issue-to-issue level (Fig 1). Furthermore, we
developed a structured typology of indicators to characterize
the linkages between issues and indicators to determine
where condition assessment, warning signal, threat
identification, trend monitoring, or performance indicators
would be most appropriate.
      </p>
      <p>
        Fig 1. Issue-to-issue triples in a DPSIR framework.
Musker et al. (2015) incorporates the concept of resilience
into Springer et al. 2015’s sustainability ontology. The
concept of resilience in food systems may assist with
understanding both the current state of the food system and
potential methods and strategies to increase food and
nutrition security worldwide [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. Our current conceptual
ontology utilizes attributes of resilience [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] to discover
strategies to alter the nature of a relationship or linkage
through building resilience (Fig 2). For example: How can
the relationship be strengthened? Reduced? Changed in
direction? What capacity needs to be built to achieve the
correct (or most sustainable) directionality of the
relationship? How do you measure these capacities?
Fig 2. Building resilience as discovering strategies to change
nature of relationships between issues.
      </p>
      <p>We have described the Springer et al. (2015) and Musker et
al. (2015) ontology in terms of RDF triples; however, our
issues and concepts within our ontology can be expressed
using OWL. The main concepts are Classes, Properties
(subdivided into Object Properties and Data Properties) and
Individuals. Springer et al. 2015 represented this
information in the form of a web, however using Protégé, it
is possible to translate this web of relationships into formal
logical assertions. Since the component issues are expressed
using terms from FAO’s AGROVOC thesaurus, we have
connected the URI of the term to our ontology. Currently,
our ontology process is unconstrained, meaning any concept
can be connected to any other concepts.</p>
    </sec>
    <sec id="sec-5">
      <title>III. NEXT STEPS IN ONTOLOGY DEVELOPMENT</title>
      <p>Our food systems ontology will assist in classifying the
communities of practice who will use the ontology, what
kind of information they gather and types of information
they seek. This information would be freely available to
other actors, reducing unnecessary repetition in research,
while assisting the creation of partnerships. Information,
data, and results could be reviewed by others for
decisionmaking processes to be transparent, and open access.
Our team is building upon the current ontology and
including already existing ontologies, the Sustainable
Development Goals Interface Ontology, Food On,
Environment Ontology (ENVO), and National Center for
Biomedical Ontology (NCBO), and will expand greatly to
incorporate food, diets, eating, exercise and the human
microbiome. This work will involve collaboration among
academic and industry experts to ensure accuracy in our
ontology development.</p>
      <p>The boundaries of this ontology will focus on food and food
systems, agricultural supply chains, ecosystem health,
nutritional status of the global population, and the
technology available to supply data about these knowledge
domains.</p>
    </sec>
    <sec id="sec-6">
      <title>IV. USER-FOCUSED ONTOLOGY</title>
      <p>While ontologies are indeed conceptually interesting; the
power lies in the ontology’s ability to facilitate information
discovery and retrieval for the decision-maker. Due to this
fact, it is crucial while building ontologies to consider the
audience who requires the information, and could make the
most use out of the ontology. We seek to understand the
communication requirements necessary to allow the
information discovered by ontology development to be
useful quickly buy the target user group. Outlined are five
ways that our ontologies will enable decision-makers to
assess the information efficiently and effectively.
1.</p>
    </sec>
    <sec id="sec-7">
      <title>COMMUNITIES OF PRACTICE</title>
      <p>
        Our platform seeks to be useful to all communities of
practice, within the
environment-agriculture-food-diethealth knowledge spectrum. Communities of practice are
defined as “groups of people who share a concern or a
passion for something they do and learn how to do it better
as they interact regularly” [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. We define these communities
of practice as any stakeholder whose decisions positively or
negatively affect the sustainability of the food system and
include food manufacturing companies and corporations,
academic researchers, consumers, policy makers, producers,
etc. A successful platform may help the individual actor
reconcile the different languages and conceptual
assumptions of the multiple communities of practice within
the food system in order to achieve something synthetic
across the whole chain of causality.
      </p>
    </sec>
    <sec id="sec-8">
      <title>2. SEMANTICS</title>
      <p>Currently, throughout the communities of practice,
semantics create a real barrier to progress. Very different
terminology is used for indicators, metrics, and fundamental
issues. Development of semantics will simplify information
and data discovery and can lead to indicator selection that is
usable by all actors throughout agricultural supply chains
and health systems. Our platform will greatly reduce this
confusion by creating a library of health and food system
terms, assessing where and how they are used and who uses
them, that will allow the communities of practice to not only
understand each other, but collect and share interoperable
data. We will take advantage of existing vocabularies, such
as CABT, AGROVOC, NALT, GEMET, and others to
provide a foundation for semantic standards and
development.</p>
      <p>3.</p>
    </sec>
    <sec id="sec-9">
      <title>COMPLETENESS</title>
      <p>Although communities of practice may use different
language to describe the issues they care about, perceive
different relationships among those issues, and use different
indicators to measure them, there exists totality of
sustainability issues that can be addressed by each
community of practice.</p>
      <p>However, the necessity of completeness could depend on
the communities of practice and how they perceive
boundaries. One option is, across these communities of
practice, a linked global network of this sustainability
information could act as a boundary of all the possible
issues any given community could consider. Communities
of practice can use such a global list to ensure that they are
representing the complete list of issues for their cases. In
this case, our ontology could demonstrate a large list of
issues that must be taken into account in order to achieve a
sustainability goal.</p>
      <p>The second option takes the belief that completeness is not
an achievable goal, and communities of practice exist in part
because they are defined by conventions on what
concepts/entities are intrinsic actors (state variable) and
which are extrinsic drivers and there are no explicit
boundaries on how far one could pursue a sequence of
individually informative links. For this second option, a
wide-ranging ontology like ours does the opposite – one can
query on what kinds of nodes and edges are (say) one or two
steps from those included in an analysis or decision tree,
look at the list, and ask what important processes/entities
have been excluded and how much one cares about those
sources of incompleteness.</p>
      <p>
        At the same time, such a comprehensive list can be
unwieldy to sort through, especially with key differences
depending on semantics, scale, scope, sector, commodity
focus, etc. One way of minimizing the amount of
information needed to represent all key issues while
simultaneously assuring completeness is to apply an
optimization algorithm to the information set defined by the
stakeholder group to solve the “minimum covering set”
(MCS) problem. Such an algorithm selects the minimum set
of indicators from a broader set of known indicators
required to represent the set of issues that are deemed
important by the a particular community. Different
algorithms can be used to solve the MCS problem, including
a heuristic minimization approach [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] and an integer
programming method [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. Regardless, communities of
practice can use such a tool to consistently ensure
completeness and consideration of tradeoffs while selecting
indicators to represent the issues they care about.
4.
      </p>
    </sec>
    <sec id="sec-10">
      <title>WORKFLOWS AND PROCESSES</title>
      <p>
        Workflows are essential when utilizing data and information
that is traceable, transferable and interoperable among many
communities of practice. Such a process has been successful
in the conservation community at creating “best-practice”
decision-support systems for conservation projects
[
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. Information technology tools such as MIRADI
(https://miradi.org/) help conservation partners develop
boundaries, measurements, goals, and strategies for specific
uses that can be shared across user groups without a loss of
generality. If a certain process works well for a certain
communities, this process can be documented, maintained,
and utilized by other communities as well.
      </p>
      <p>
        New knowledge generated through scientific research,
cultural exchange, social development, and practical
experience is constantly revealing new issues as other issues
are addressed. Consistent approaches to identify
sustainability issues of importance and indicators to measure
them must be flexible enough to incorporate emerging
issues, insights, and data sources [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. We continue to
explore how explore directionality among concepts and
applications of scalability within, or complementary to, our
ontology.
      </p>
    </sec>
    <sec id="sec-11">
      <title>V. USE CASE</title>
      <p>Currently, the Agricultural Sustainability Institute at UC
Davis is working with the Sacramento Area Council of
Governments to determine conservation land use planning
potential. A wide range of stakeholders are involved,
including local government planners,
landowners/developers, federal and state resources
regulators, environmental advocacy organizations, and
agricultural groups/individual landowners. Many of the
stakeholders have similar concerns over specific issues and
desires for interoperable data but do not understand each
other’s needs or have a place to express these concerns. The
goal of this use case is to test our ontology of sustainability
to provide guidance on the collection of existing data and
modeling needed to underpin an effort to define regional
strategies for the conservation of natural resources and
support for management of those lands for environmental
and economic benefits.</p>
    </sec>
    <sec id="sec-12">
      <title>VI. CONCLUSION</title>
      <p>Our ontology will be hosted at the University of California,
Davis, at the new International Center Food Ontologies,
Operability, Data, and Semantics (IC-FOODS), and will
have support from the Agricultural Sustainability Institute,
Food Science and Technology, the Information Center for
the Environment, and the Innovation Institute for Food and
Health. Plans are underway to host the information facility
in the university digital library, in collaboration with the UC
Davis Data Science Initiative. We are hoping to bring
several communities of practices into our ontology
development, both in the ontology creation side, and the
user side. These communities of practice include regional
and national governments, academics, industry
professionals, non-profit organizations, and foundations,
with expertise from data security and curation to domain
expertise in human health and nutrition, agricultural supply
chains, and intellectual property.</p>
      <p>Questions we will be able to help communities of practice
answer:
1.</p>
      <p>What widely-measured variables documenting
human, social, and environmental health are
interconnected in a food system and nutritional
context? What processes, actors, and
measures/indicators definitively need to be
included in a conceptual framework for
understanding impacts of food system on health
and well-being, and where does one set defensible
system boundaries?
How can we classify and formalize terminology for
these connections to help relevant actors to
exchange and integrate information efficiently and
accurately, to make well-informed decisions
regarding economic, social, and environmental
dimensions of sustainability? What data does one
need, and where are the data gaps?
How can data be most effectively curated to
maintain the integrity of rigorous scientific
research surrounding human nutrition and health,
together with economic, social and environmental
sustainability, while ensuring that these data are
interoperability among disciplines, actors, sectors,
and scales?
Upon completion of our ontology, these are examples of
practical questions that users would be able to address:</p>
    </sec>
    <sec id="sec-13">
      <title>How to quantify sustainability of a food product (e.g., a chocolate bar) from a social, human nutrition, environmental and economic perspective?</title>
    </sec>
    <sec id="sec-14">
      <title>Which indicators could describe the current state of</title>
      <p>sustainability for, as an example, Switzerland’s
imported goods? Which indicators could be used to
identify potential shocks to Switzerland’s food
system and ways to monitor these vulnerabilities?</p>
    </sec>
    <sec id="sec-15">
      <title>How can existing data be used to understand the link between food prices, human health outcomes, and droughts?</title>
    </sec>
    <sec id="sec-16">
      <title>Which network of actors in the food system has the ability to make positive changes in the supply chain of a commodity in a specific production region, (e.g.: dairy milk in North America)?</title>
    </sec>
  </body>
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