=Paper=
{{Paper
|id=Vol-1944/paper1
|storemode=property
|title=Food Security Goal Analysis using Multi-Objective Reasoning: Treated Sewage Water Case Study
|pdfUrl=https://ceur-ws.org/Vol-1944/paper1.pdf
|volume=Vol-1944
|authors=Amal Aldababseh,Davor Svetinovic
}}
==Food Security Goal Analysis using Multi-Objective Reasoning: Treated Sewage Water Case Study==
https://ceur-ws.org/Vol-1944/paper1.pdf
Food Security Goal Analysis using Multi-Objective
Reasoning: Treated Sewage Water Case Study
Amal Aldababseh Davor Svetinovic
Water and Environmental Engineering Electrical Engineering and Computer Science
Masdar Institute of Science and Technology Masdar Institute of Science and Technology
Abu Dhabi, United Arab Emirates Abu Dhabi, United Arab Emirates
aaldababseh@masdar.ac.ae Email: dsvetinovic@masdar.ac.ae
Abstract—Food security, the ability to access safe, sufficient, individuals. In arid and semi-arid regions, like the UAE,
and healthy food, is fundamental for governments to ensure limited water resources, high population growth, harsh weather
societies’ healthy lifestyles and the well-being of all citizens. conditions and climate change have contributed to limit the
Food sovereignty is one of the vital requirements to achieve food
security at a national level. Societies have introduced different options to increase food production and put the farmers and the
mechanisms to increase their national food production. The use governments under high pressure to achieve food security [3],
of treated sewage effluent in irrigated agriculture sector is one [4]. The use of non-conventional water resources, e.g., treated
of the main adaptation mechanisms. Governments encourage municipal wastewater, also known as treated sewage effluent
the use of this new source by providing technical and financial (TSE), was introduced as a key adaptation measurement to
support and subsidizing the price of water. However, farmers
are hesitant to benefit from the subsidies as they do not have climate change and drought. Since then, the use of TSE to
access to the required information or they come across conflicting overcome the limited water resources in irrigated agriculture,
information from different resources. These barriers prevent and to minimize the impact of wastewater disposal on the en-
many farmers from using treated sewage effluent on their farms, vironment was successfully demonstrated in several countries
which leads to either using desalinated water, that is expensive [5], [6]. However, the adoption of this measurement at large
and energy intensive, or decreasing agriculture activities, which
subsequently decrease local crops productivity and thus increase scale and in many countries, including the UAE, is still facing
country reliance on food imports. several constraints including public and farmers acceptance
This paper defines information requirements for farmers, [7], [8], health risks [9], [10], and potential environmental
based on a case study of farmers’ use of treated sewage effluent in impacts [11], [12].
irrigated agriculture in Abu Dhabi. The multi-objective reasoning It is important that farmers understand the added value
with constrained goal models was used to define constraints and
optimization goals over multiple objective functions, refinements of using TSE in irrigated agriculture. In the case of UAE,
and their numerical contributes. Several interviews were con- wastewater is being treated to tertiary level. Which means
ducted, with those who have used treated sewage effluents for that the quality of water produced is suitable for direct use in
irrigation, to validate the generated model, and help in defining irrigated agriculture. The UAE treats around 265 MCM/year
how farmers can also contribute to defining information needs (around 39% of the produced wastewater)[3] out of which
to maximize the use of treated sewage effluent in agriculture.
Index Terms—Goal-oriented requirements engineering; sus- 159 MCM (around 60%) is reused per year [3]. This figure
tainability; food security; social acceptance shows that the use of TSE in irrigated agriculture is still limited
despite the Government technical and financial support to help
I. I NTRODUCTION farmers in using this non-conventional water resource. This
Food security was introduced in 1974 at the World Food might be related to the limited knowledge on how to use TSE
Conference with emphasis on food supply. It was further in a safe manner, the type of crops to produce in terms of its
developed over time to cover several aspects including food suitability to the climate (drought resilience and salt-tolerant),
supply, food availability, and affordability. The latest and most and the TSE suitability to agriculture.
commonly used definition of food security was introduced Researchers and technical teams look always for the best
by the State of Food Insecurity in 2001 as “a situation that technology to enhance the quality and quantity of TSE, and
exists when all people, at all times, have physical, social how to eliminate the environmental impacts of using the
and economic access to sufficient, safe and nutritious food effluent in irrigated agriculture [13]. However, limited studies
that meets their dietary needs and food preferences for an focus on farmers’ knowledge requirements to encourage the
active and healthy life” [1]. The four main components of use of TSE [14], [15].
food security as identified by the United Nations Food and Engaging farmer is a critical element in encouraging broader
Agriculture Organization are availability, access, use, and use of TSE in irrigated agriculture. A good example to be
stability [2]. investigated is that of Abu Dhabi. In 2012/2013, Environment
Under the current climate change conditions, food avail- Agency-Abu Dhabi launched an innovative program, with the
ability and stability become major concerns for nations and objective of introducing the TSE in irrigated agriculture to in-
crease crops production and minimize the use of groundwater already reached in 2006, along with Kuwait, Gaza Strip, Qatar,
in irrigated agriculture. The project managed to treat almost Saudi Arabia, Maldives, and the Bahamas.
27 million liters of water a day to a standard good enough for In response to this global, regional, and national water
agricultural use. It was used on 220 farms across the emirate stresses, mitigation, and adaptation measures were introduced
[16]. at all levels to cope with climate change impacts and to
This paper intends to define the goals and requirements for mitigate its occurrence. As agriculture sector consumes around
maximizing farmers’ use of TSE. It analyzes and reports the 70%-76% of the total water [20], [22], one of the main
initial results of Abu Dhabi’s experimental study by applying introduced mitigation and adaption measures to help cope with
the CGM and its reasoning tool CGM-Tool introduced in the water stresses is the reuse of TSE in irrigated agriculture
[17]. The Constraints Goal Model (CGM) which considers [20]. It is estimated that around 200 million farmers, at the
multi-objectives while helps in maximizing the benefits, and global level, farming at 20 million ha, use treated, or partially
the adoption of stakeholders’ participatory approach, offer a treated, or untreated wastewater [22].
substantial potential to not only achieve the required level of Farmers are the key actors in the agriculture sector. The
TSE use in irrigated agriculture but also in achieving end-user use of TSE in irrigated agriculture depends on farmers’
engagement among other preferential goals. understanding and acceptance of the idea. However, if farmers
The advantage of using this model is to enable users refining are not fully aware of the benefits and constraints of using TSE
goals, expressing preferences between the goals and their in irrigated agriculture, then the use of this resource can prove
refinements, as well as associating numerical attributes to goals inadequate in many ways, including limited use of TSE by
and their refinements. This helps in optimizing goals over farmers [15], wasting a valuable source that can increase the
multiple objective functions and their numerical attributes and vegetation cover while adapting to climate change [20], [14],
in defining the constraints as well as the motivation of farmers and functional requirements for the TSE not being provided
(i.e. maximize preferences) who chose to use TSE. to farmers who might be unhappy with the use of TSE in their
The main research questions will focus of eliciting farm- farms [14].
ers’ requirements for using TSE, especially their information A study by Mizyed [14] in arid and semi-arid areas identi-
needs: fied the main challenges for TSE use; those include the limited
RQ1. What encourages farmers to use TSE in irrigated knowledge available and shared with farmers concerning the
agriculture? socio-economic, and the legal and political considerations of
RQ2. What information have farmers received, or would using the treated effluent. Furthermore, he confirmed that
like to receive, to enable them to take an informed decision? farmers who received technical training, information and
What other information should be shared? knowledge on the proper use of TSE were happy and reported
Interviews with five farmers who accepted to use TSE in a high level of satisfaction of using TSE in their farms.
their farms were conducted. The aim of the interviews was
to validate the model and understand the type of information A. Goal-Oriented Requirement Engineering
farmers have received, and what kind of information farmers
The literature in the irrigation field area suggests that
have been looking for in order to define the minimum required
knowledge of constraints and opportunities associated with
information and knowledge.
the use of TSE in irrigated agriculture is very crucial to
guide policy formulation and provide a better understanding
II. BACKGROUND AND R ELATED W ORK
of the limitations as well as the trade-off, to inform better
Climate change imposes threats to human’s ability to decisions making process [20]. Van Lamsweerde [23] indi-
achieve sustainable development. It further threatens ecosys- cates that systems could fail if their requirements are not
tems and natural resources sustainability. Climate change has adequately identified and analyzed. Therefore, knowledge is
generated different climate-induced disasters (e.g., drought, very crucial to encourage farmers using TSE in their farms to
flash floods, heat-waves, and sea-level rise). It is estimated that ensure achieving food security and release pressure on water
climate change will contribute to 250,000 deaths every year resources.
between 2030 and 2050 [18]. It will also decrease the amount The stakeholders of the reuse of TSE need to obtain the
of available water resources in some regions including the minimum knowledge requirements to enable them to take in-
Middle East by more than 10% [19]. As of 2006, around 11% formed decisions. However, no specific efforts have been made
of the total world population lived under chronic water scarcity to define the needed requirements. Sharing of unnecessary
threshold as defined by the UN, which is 1000 m3 /capita.year; information and requirements may jeopardize stakeholders’
moreover, this percentage is projected to increase to 38% ability to take right decisions as this may lead to confusion,
by the year 2025 [20]. However, there are huge disparities and unnecessary investments in money, time, and efforts [24].
between regions and countries. According to the IPCC report, Requirement Engineering (RE) could be used to define the
by the year 2025 the Middle East region will be suffering minimum requirements and information needs to maximize the
the most and reaching the 100 m3 /capita.year [21]. This is use of TSE in irrigated agriculture. RE facilitates elicitation,
the minimum survival level that the United Arab Emirates has evaluation, specifications, and analyses processes, as well as
Copyright © 2017 for the individual papers by the papers' authors. Copying permitted for private and academic purposes. This volume is published and copyrighted by its editors.
the evolution of the objectives of a system, its functionality, in investigating the usability and replicability of the new model
and the constraints a system might face [23], [25]. and its associated tool in a different domain. The advantage of
RE helps in examining and understanding the relationships using this model, as stated by [17] is to enable users refining
among the system’s social actors [26]. It leads to the de- goals, expressing preferences between the goals and their
velopment of the conceptual framework for modeling and refinements, as well as associating numerical attributes to goals
analyzing processes that involve multiple stakeholders as well and their refinements. This helps in optimizing goals over
as fulfilling the intention [27]. multiple objective functions and their numerical attributes.
RE defines the needs of a system and its users [24],
[26]. The relationships between actors in the domain usually A. Research Questions
lead to intentionality. This can be better described using the The main research questions focus of eliciting farmers’
Goal-Oriented Requirement Engineering (GORE) approach, requirements to maximize TSE use in irrigated agriculture,
which involves the understanding of why a system function especially their information needs.
is required, and how those functions can be implemented RQ1. What encourages farmers to use TSE in irrigated
[23]. Furthermore, there are several advantages for using agriculture?
GORE approach; those include: it allows for scalability of To define the requirements, it is crucial to understand what
the application domain based on assumptions, provides a encourages farmers to use TSE in irrigated agriculture (e.g.,
rationale for requirements, provides traceability, and provides save money by using a cheaper resource, increase productivity
assignment of responsibilities [25]. of crops as TSE has more nutrients, conserve fresh water
GORE approach uses goals for all RE processes: eliciting, by relying on TSE, maximize profit by decreasing the ex-
evaluation, negotiation, structuring, documentation, analysis, penditures and increasing the profit). However, are farmers
and evolution [23], [25], [26]. Goals are statements of intent aware of the environmental and health associated impacts? Are
that the system should satisfy through the collaboration of its farmers familiar with how to implement the needed monitoring
agents [23], [25], [28], while agents are the players who define programs? Are farmers aware of the positive environmental
the scope of the system [23], [26], [27]. consequences of using TSE? Will farmers’ information re-
During the past two decades, several GORE modeling tech- quirements vary from those who rejected to use TSE in their
niques have been established and advanced. The most popular farms?
methods among those are Keep All Objects Satisfied (KAOS) RQ2. What information have farmers received, or would
[23], [29], [30], i* [26], NRF Framework [25], TROPOS [27], like to receive, to enable them to take an informed decision?
[31], and GRL [28]. However, those modeling techniques What other information should be shared?
do not have clear means to track or respond to continuous To define the requirements, the information shared with
changes in real systems, therefore, lack of optimization goals farmers needs to be identified, as well as sharing frequency,
and scalable reasoning facilities are the common limitation and the preferred methods. This helps in determining the
among GORE methods. sufficiency of the communicated information, the advanta-
In response to these common limitations, Nguyen et al. geous frequency, and the effectiveness of the used methods.
[17] have proposes a new expressive extended goal-oriented The use of TSE in agriculture is a complex process as it
modeling language, named constrained goal model (CGM). has pros and cons that farmers must be aware of before
In addition, a set of automated reasoning functionality over taking decisions. For example, would farmers need to know
this model was developed in a tool named CGM-Tool. The how to calculate the cost-benefit and how and when will
newly developed model, CGM, has the following advantages be the return on their investment? What are the trades-off
as explained in [17]: between environmental health risks, price, and sustainability
• Goals and goals refinements: CGM makes explicit the and how are these shown? Is it also critical to understand if the
notion of goal refinement. information communicated with farmers is easy to understand?
• Domain: the model provides an explicit representation How did this information influence farmers’ decision-making
of domain assumption, allows for expressing preferences process? In addition, how to present all these factors in one
between goals and refinements. single, simple graph that captures the requirements and their
• Constraints: the model associates numerical attributes to relationships?
goals and refinements for defining constraints. B. Case Description: Use of TSE in irrigated agriculture in
• Optimization: the model defines optimization goals over
Abu Dhabi
multiple objective functions, refinements, and their nu-
merical attributes. In 2012–2013, an innovative program was launched by the
Environment Agency of Abu Dhabi, with the objective of
III. R ESEARCH M ETHOD introducing TSE in irrigated agriculture to maximize crops
Engaging farmers in defining goals and requirements could production and minimize the use of groundwater in irrigated
be a critical element in encouraging and maximizing TSE use agriculture. This case study is used to:
in irrigated agriculture. Applying the newly developed CGM • Validate the developed CGM model: the outcomes of the
model and tool on the use of TSE in irrigated agriculture helps interviews and meetings help in validating the designed
goal models to maximize the use of TSE in irrigated Setting preferences in the CGM and checking well formed-
agriculture. Discussions focus on how farmers currently ness:
receive information, and why this information should Once the first two steps mentioned above are done, the next
be enhanced and effectively communicated, the expected step is setting preferences in the CGM and running the CGM-
benefits, the constraints they have faced as well as the Tool to generate all possible realizations:
benefits of using TSE based on their experiences in the • First, the check well-formedness function is used to
program. test and verify the formedness and the validity of the
constrained goal model by analyzing Empty Diagram,
C. Data collection
Invalid Goal Node, Refinement Validity Check, and Un-
We reached out to the program’s teams to provide access to declared Variable. A CGM model is well-formed if all
the program details and current beneficiaries (the farmers). The of these elements and their relations are modeled and
main data collection method for this research is the literature interconnected correctly [32]. The test is performed by
review (observations from the literature help in portraying the calling the Check well-formedness function, and then
full picture of the model), case studies analyses (enrich data calling the Run Analysis function
collection and knowledge generation), and semi-structured • Second, the model is generated by calling the Generate
interviews with the stakeholders, mainly the farmers who have Scenario function. The model checks for consistency first,
accepted using TSE in irrigated agriculture. and then produces the scenarios. Produced scenarios are
Questions of the semi-structured interviews are of open- saved under the Scenarios Folder (under the developed
ended style, to enable stakeholders to share details they feel model).
appropriate and relevant. Questions cover the main reasons to • Third, by using the Launch reasoner function, the model
get involved in the program, the expected benefits, constraints, generates all possible realizations after defining optimiza-
environmental motivations, sustainability concerns, availability tion priorities. The selection of the most reasonable one
of needed information, at any stage of the program develop- is based on the stakeholders’ preferences. However, this
ment farmers were engaged, and do they share their feedback third step is not performed under this research due to time
with government officials, how and how often. A list of the constraints and data accessibility limitations. To use the
interview questions is provided in the Appendix. Launch reasoner, SMT variables and global constraints
D. Modeling and Data Analyses need to be identified by the stakeholders. Stakeholders
can express preferences on the requirements, constraints,
The modeling follows five main steps presented in [17]: refinements, and tasks [17]. Preferences are expressed
Define and model the CGM goals, refinements, and domain in CGM-Tool by attributing penalties and rewards for
assumptions: requirements and tasks, using numerical objectives to
Goals, requirements, functional and non-functional require- optimize, and introducing binary preference relations
ments are defined based on literature review and best practices between elements and refinements.
and modeled using the CGM-Tool. A functional requirement
is the MaximizeTSEUtilization in irrigated agriculture. Non- IV. R ESULTS AND D ISCUSSION
functional requirements include ImproveLivingStandards, Pro-
A. Constrained Goal Model
tectEnvironment, and NetPositiveRevenue.
According to [17], elements and refinements can be enriched The results of modeling the minimum requirements for
by user-defined Boolean constraints. This can be expressed in maximizing the use of TSE in irrigated agriculture using
three different methods (i) graphically as relation edges, (ii) the CGM-Tool show that it is possible and practical to in-
textually as Boolean formulas, and (iii) as user assertions. The clude the functional requirement MaximizeTSEUtilization in
relation edges and user assertions are both used to develop the irrigated agriculture, as well as non-functional and optional
CGM model. requirements ProtectEnvironment, ImprovingLivingStandards,
In CGM-Tool, users can interactively mark/unmark every and NetPositiveRevenue, as shown in Figure 1.
goal, task, or domain assumption as satisfied (i.e. true), Figure 1 presents the overall model with no specific realiza-
or unsatisfied (i.e. false). Marking requirements as satisfied tion. It is presented here to show the main requirements and
makes them mandatory. Unmarking requirements means they relations between them in order to maximize the use of TSE
are “nice-to-have” or “preferable.” MaximizeTSEUtilization is in irrigated agriculture:
asserted as satisfied to make it mandatory. • Requirements: round-corner rectangles in Figure 1 are
Realization of the Constrained Goal Model: root goals, representing stakeholders’ requirements. Ac-
After defining the CGM backbone, and the constraints, cording to [11], farmers are interested to use TSE in
MaximizeTSEUtilization is proposed as the only satisfied their farms to maximize their profit, by either increasing
(marked) based on users’ assertion. Different realizations can their production or decreasing the cost. It was identified
be generated by the CGM-Tool. Those different realizations in [33], [34], [35] that governments’ main objective is
represent alternative ways of refining mandatory requirements to minimize the impact on environment by maximizing
in line with the user-defined constraints and assertions. the use of treated wastewater in irrigated agriculture.
Fig. 1. The constraint goal model of the maximizing TSE use in irrigated agriculture in UAE
The main aim of the constrained goal model, presented achieve the UseSuitableCrop. Refinements are labeled, so
in Figure 1 is to achieve the main requirement, Maxi- it is easier for stakeholders to review and revise those
mizeTSEUtilization, which is mandatory. MaximizTSEuse relationships as necessary.
has one refinement (R1), consisting of six sub-goals: Pro-
tectGroundWater, MinimizeSocialImpacts, ProtectProp- B. Relation Edges
ertyValue, SelectProperCrop, ProtectPublicHealth, and In the developed model, the elements and refinements were
ProtectSoil. Since R1 is the only refinement of the re- enriched by user-defined constraints, which were expressed
quirement, all these sub-goals should be satisfied in order graphically as relation edges. In their work [17], they used
to satisfy it. However, there might be one more one way relation edges in addition to Boolean and SMT formulas.
to refine an element. For example, MinimizeSocialImpacts In this paper, the focus is on using relation edges and user
is further refined either by R12 into the single goal assertions.
ByFarmers or by R11 into the single goal ByGovernment. The relationships between elements and refinements devel-
Similarly, ProtectGroundWater and ProtectPropertValue oped in this model are of four types:
+
have one and two possible refinements, respectively. • Contribution edges (presented as ! in Figure 1). Six
• The requirements that are not defined as mandatory are contribution edges are found in the model. For example,
+
optional “nice-to-have” requirements. Those represent de- ReduceGWUse ! ProtectEnvironment, means that if the
sired states of affair needed so the model can be achieved, source element ReduceGWUse is satisfied, then also the
e.g., ImproveLivingStandards, ProtectEnviornment, and target element ProtectEnvironment should be satisfied,
NetPositiveRevenue. but not the opposite.
-
• Intermediate goals: in their research, [22], [14] identified • Conflict edges between elements (presented as ! in
several intermediate goals to be achieved in maximizing Figure 1). Four conflict edges between elements are
-
use of TSE in irrigated agriculture. Those intermediate found, like StopUseTSE ! UseTSE.
goals presented as ovals in Figure 1, including those • Refinement bindings between two refinements (presented
six intermediate goals ProtectGroundWater, Minimize- as $ in Figure 1, is used to state that the two refinements
SocialImpacts, ProtectPropertyValue, SelectProperCrop, are bound. Only one refinement binding is identified,
ProtectPublicHealth, and ProtectSoil. However, since between R18 and R19. The refinements R18, R19 are
these intermediate goals need other goals to be achieved, bound; as such binding reflects that FindSuitableCrop $
9 other lower-level leaf goals (called here 1-lower-level PlantSuitableCrop are also bound. This means that they
goals) are developed under the main 6 intermediate goals. both represent two different illustrations but of the same
Furthermore, 3 of the 9 goals have more lower-level global choice [17].
++
goals. These are named here second low-level goals and • Bi-Contribution edges, presented as ! in Figure 1).
defined based on [20], [15], [14]. These goals are Control- ++
The SaveWater ! GWRecharge means that a binding
PathogenesInTSE, EvaluateRisks and UseSuitableCrops. positive refinement exists between the two elements. Two
The second lower-level goals for these three 1-lower level bi-contribution edges are identified in the model, both are
goals are five goals. related to water saving.
• Tasks present as hexagons in Figure 1. 31 tasks were iden-
tified under the intermediate goals (the first and second C. Result of Well-Formedness Analysis
level lower-level goals). Tasks include ApplyAmendments, The result of running check well-formedness analysis
ProtectFromChemical, SaveFreshWater, CutTransporta- showed that the diagram, goals nodes, refinement, and vari-
tionCost, EliminateTraditionalCrops, and ConsultFarm- ables were all identified as the analyses tasks were completed
ers, among others. without finding any errors.
• Domain Assumptions are propositions about the domain
that need to hold for a goal refinement to work. They are D. Scenario Generation
shown as rectangles in Figure 1. Five domain assumptions To generate scenarios, one can set MaximizingTSEUtiliza-
were identified, NoImpact, HighCropYield, NoProblems, tion as the only mandatory requirement, and running the
SuitableCropsKnown, and FarmersUseTSE, according to Generate Scenario function, the developed CGM model would
[14], [34]. have more than 36 different realizations.
• Refinements represent the alternatives of sub-elements The results of presenting the developed CGM model to
that are necessary to be achieved. They are numbered farmers are summarized below under the two main research
black bullets at the merging points of the edges connect- questions. The following paragraphs depict main points of
ing a group of source elements to a target element. For discussion and findings, based on farmers feedback:
example, (SuitableCropKnown and PlantSuitableCrop) RQ1. What encourages farmers to use TSE in irrigated
R19
! UseSuitableCrop, while R19 denotes the refine- agriculture?
ment’s label. This means that the SuitableCropKnown and The model involves a large number of goals, intermediate
the PlantSuitableCrop are both necessary alternatives to goals, tasks, and domain assumptions. The model also shows
how complex the relationships between the different elements
to maximize TSE use. This makes the work to maximize the shared information was “limited to the cost, quantity of TSE
use of TSE in irrigated agriculture a complex process with allowed per hectare, and how to get access and be a part
different tasks to be accomplished. of the TSE use program.” Furthermore, the farmers indicated
In this model, MaximizeTSEUtilization is identified as the that they had many questions that went unanswered like who
only mandatory requirement to be achieved. However, farmers is responsible to monitor the quality of the used TSE. Addi-
expressed different opinions concerning the nice-to-achieve tional unanswered questions included: Is there any guarantee
goals. Although the government might be interested in max- from the government that water is safe and has no negative
imizing the use of TSE, farmers are interested in increasing impacts on crops? Will the use of TSE negatively affect crops’
net positive revenue, or improving their living standards, or consumption? What kind of crops should be irrigated by TSE?
protecting the environment, mainly water resources (only one As such, the awareness of the pros and cons of using TSE in
farmer expressed his interest in protecting the environment). irrigated agriculture supported by the needed details should be
One farmer stated that he frequently asked critical questions articulated and considered.
as he is “interested in using TSE for economic reasons” It was also observed during the discussion with the stake-
and that he does not “use much fertilizers in the farm when holders that in order to reflect stakeholders’ opinion and make
using TSE for irrigation as the use of TSE would provide the CGM model very practical and flexible, it is necessary
the needed nutrients.” Another farmer, however, had more to define the impacts of positive and negative constraints.
conservative reasons for using TSE and stated that his previous Constraints can be integrated in the model using the Launch
farming practices were broadly using desalinated water, which reasoner function to optimize intended solutions, as the con-
is energy consuming and it was his “belief that using TSE straints’ impact might be a determinant factor in defining the
or other water resources is the only way to sustain the minimum requirements for framers to use TSE in irrigated
limited water resources in the UAE,” and that using such non- agriculture.
conventional water resource had the personal and social reward
of “more income and less damage and unsustainable use of V. VALIDATION
water resources.” However, two farmers indicated that “ethical Two techniques were used to validate the initial results. The
considerations are important to consider when using TSE in first technique was used to check if the model was built up
irrigation” as those are an influencing factor in the decision correctly and if it could be used in this domain, and performed
making process and it is essential to “inform our clients that by running Check Well-formedness Analysis function of the
those crops are irrigated by TSE.” Furthermore, the ethical CGM model. The result of the run confirmed that the model
considerations were also an influencing factor in taking the was well formed. This confirmed the replicability of the
decision to use TSE as farmers “believe its our responsibility CGM model and the possibility of using it for other technical
to conserve water and protect the environment.” domains than the computer systems as reported by [17]. The
The 32 identified tasks are very important for farmers to second technique was used to validate if the requirements and
be aware of, those are crucial to help farmers in deciding on refinements captured in the model based on domains experts,
whether to use TSE in their farms or not. The uncertainty are in line with the domain experts’ opinion (a group of
associated with these requirements, as well as the complexity farmers who have used TSE in irrigated agriculture in Abu
in terms of the number of goals and tasks and their connec- Dhabi). Participating farmers (5) agreed that the developed
tions made farmers a bit hesitant to use TSE. Furthermore, CGM model captures all requirements, however, what was
desalinated water is highly subsidized, and therefore, the use identified as a requirement in the model, was considered as
of clean desalinated water is considered an economic viable an ultimate goal for farmers. Farmers also confirmed that the
option, that is also socially acceptable. presented graph was easy to understand, mainly the way it
RQ2. What information have farmers received, or would presented the relationships between the goals and tasks, and
like to receive, to enable them to take an informed decision. the possible refinements. However, farmers recommended that
What other information should be shared? the model should be prepared using the local language, Arabic,
The main model and all related requirements, goals, tasks, as it would have been easier for them to understand.
and domain assumptions, as well as, the relations between Farmers expressed their concerns mainly when it came to
nodes were present in one single graph. Farmers indicated that the social attitude concerning the consumption of crops irri-
they are still not aware of the benefits of using TSE except gated by TSE. Therefore, farmers identified social acceptance
its reduced cost in respect to desalinated water. Furthermore, as the main concern and proposed to consider it as a mandatory
farmers indicated that the CGM model is a nice simple way to goal rather than a sub-goal. Three of the farmers indicated
present the pros and cons of TSE use in irrigated agriculture. that they would use TSE in irrigated agriculture if local
Framers indicated also that the soil pollution and groundwater communities would understand the requirements presented in
over exploitation aspects have never been discussed; hence, the scenario. Two farmers indicated that environmental and
farmers are not aware of the needed procedures to make sure water concerns should be highlighted as the main concerns
that soil and health are both safe after using TSE. to convince farmers using TSE in their agriculture. They
All interviewed farmers indicated that they had received stated that the subsidized price of desalinated water, makes
information about the benefits of using TSE. However, the it easier and safer for farmers to use without thinking of the
environmental consequences and the sustainability of ground- stakeholders and effectively obtain farmers’ feedback on the
water reserves. Two farmers indicated that the main reason use of TSE in irrigated agriculture.
for not using TSE before was the limited information they
had received. They were also not sure how much they are A PPENDIX
allowed to use, and what should be done to get TSE to their L IST OF I NTERVIEW Q UESTIONS
farms and how. The only issue they were aware of is the cost Introduction questions:
of TSE as the Government provided it with a subsidized cost.
• What is the size of your farm?
The main threats to the validity of the results are the
• What type of crops you are producing?
standard interview-based study threats and limitations. For
• What is(are) the typical planting period(s)?
example, some farmers were not available to meet with, thus
• What is the average crop production per year?
phone conversations were used instead of personal meetings.
• How do you normally finance your farm? Do you receive
Furthermore, the research faces a few external threats to
any governments incentives to establish the farm?
validity. These include the coverage (the sample was limited
• Do you have other sources of income?
to five farmers due to time constraints), and the low response
rates (the questionnaire was shared with a large sample by TSE use related questions:
email, handed to them as a hard copy, and using the phone), • Do you use TSE in your farm? If Yes, since when?
however only five responses were received. • What is the total amount you use? What is the total
amount you can use? Is there any restriction?
VI. F UTURE W ORK • Are you aware of the positive and negative impacts of
The future work will include defining different realizations the use of TSE in irrigated agriculture?
based on Launch Reasoner function. This would entail in- • What are the benefits of using TSE? Have you witnessed
volving stakeholders to define the values of different tasks in any?
terms of costs (reducing cost), work time needed (minimizing • What are the negative impacts of using TSE? Have you
time), and efforts (minimal efforts). Furthermore, penalty observed any?
could be assigned to tasks and rewards could be assigned to • How did you know about the TSE use in irrigated
intermediate goals to define quantitative values for tasks and agriculture?
goals to help in differentiating between different aspects of • Do you have any kind of monitoring program (monitor
maximizing TSE use in irrigated agriculture. Therefore, further the quality of the used TSE)?
investigation is still needed to understand the mutual influence • Is the government responsible for monitoring the quality
between requirements and constraints. of the TSE used?
Also, the interviewed sample was small due to the time • What is the optimal yield in your farm before and after
limitations, it is, therefore, necessary to expand the sample using TSE?
by involving a larger number of the interviewed stakeholders. • What is the average yield in your farm?
Finally, if the model is tested by a large sample, the full • Is your production totally irrigated by TSE? Do you use
statistical analysis could be done to provide a comprehensive other sources of water in your farms?
overview of the national minimum requirements to maximize • What is the average cost of production in your farm (total
the use of the TSE in irrigated agriculture, and test the CGM cost of using TSE vs. TSE with other water resources, if
model scalability. any)?
• How do you receive TSE? Are you connected by pipes
VII. C ONCLUSION to the source or do you buy using water tanks?
We used the goal modeling and reasoning tool in this • What are the main risks of using TSE for farmers’
research to define and model the goals and requirements to income? Did you face any issue?
maximize treated sewage effluent use in irrigated agriculture. • What are the main risks you have observed (social
The developed model consists of 61 goals that modeled the acceptance, TSE quality, TSE availability, etc.)?
importance and urgency of maximizing the use of treated • What are the health and environmental related risks you
sewage effluent. However, the potential use by farmers in have observed?
the agriculture sector, which account for high significant • If you have observed any risks, how have you managed
share of water use in the UAE, is still limited and faces them?
many challenges, due to a lack of common understanding • Did you receive sufficient information from the Govern-
of the requirements to maximize use. The model elucidated ment about the Program?
the minimum requirements to maximize the use of TSE in • How did you receive the info?
irrigated agriculture, and the required information was found • Do you think the shared information was enough?
to effectively communicate the goals to the farmers in order • What other sort of information you were hoping to get
to improve ultimate TSE use in irrigated agriculture in the or are still looking for?
UAE. This work also showed that CGM-tool can be used to • How do you judge if your production was affected by the
present the overall requirements model to the non-technical use of TSE?
R EFERENCES [23] A. Van Lamsweerde, Requirements engineering: From system goals to
UML models to software. Chichester, UK: John Wiley & Sons, 2009,
[1] FAO, “The state of food insecurity in the world. food insecu- vol. 10.
rity: when people live with hunger and fear starvation,” Report & [24] R. Ellis-Braithwaite, R. Lock, R. Dawson, and B. Haque, “Modelling the
http://www.fao.org/3/a-y1500e.pdf, 2001. strategic alignment of software requirements using goal graphs,” arXiv
[2] K. E. Charlton, “Food security, food systems and food sovereignty in the preprint arXiv:1211.6258, 2012.
21st century: A new paradigm required to meet sustainable development [25] D. F. X. Christopher and E. Chandra, “Goal oriented requirements engi-
goals,” Nutrition & Dietetics, vol. 73, no. 1, pp. 3–12, 2016. neering for non-functional factors,” International Journal of Computer
[3] O. Saif, T. Mezher, and H. A. Arafat, “Water security in the gcc coun- Applications, vol. 52, no. 7, 2012.
tries: challenges and opportunities,” Journal of Environmental Studies [26] K. Surendro and C. M. Asihwardji, “Hierarchical i* modeling in re-
and Sciences, vol. 4, no. 4, pp. 329–346, 2014. quirement engineering,” TELKOMNIKA (Telecommunication Computing
[4] S. I. Pirani and H. A. Arafat, “Interplay of food security, agriculture Electronics and Control), vol. 14, no. 2, pp. 784–790, 2016.
and tourism within gcc countries,” Global Food Security, vol. 9, pp. [27] P. Giorgini, J. Mylopoulos, and R. Sebastiani, “Goal-oriented require-
1–9, 2016. ments analysis and reasoning in the tropos methodology,” Engineering
[5] A. Murray and I. Ray, “Wastewater for agriculture: A reuse-oriented Applications of Artificial Intelligence, vol. 18, no. 2, pp. 159–171, 2005.
planning model and its application in peri-urban china,” Water research, [28] J. Hassine and D. Amyot, “A questionnaire-based survey methodology
vol. 44, no. 5, pp. 1667–1679, 2010. for systematically validating goal-oriented models,” Requirements Engi-
neering, vol. 21, no. 2, pp. 285–308, 2016.
[6] F. Pedrero, I. Kalavrouziotis, J. J. Alarcón, P. Koukoulakis, and T. Asano,
[29] W. Heaven and A. Finkelstein, “Uml profile to support requirements
“Use of treated municipal wastewater in irrigated agriculturereview of
engineering with kaos,” IEE Proceedings-Software, vol. 151, no. 1, pp.
some practices in spain and greece,” Agricultural Water Management,
10–27, 2004.
vol. 97, no. 9, pp. 1233–1241, 2010.
[30] A. Van Lamsweerde, R. Darimont, and E. Letier, “Managing conflicts in
[7] L. Raschid-Sally, R. Carr, and S. Buechler, “Managing wastewater
goal-driven requirements engineering,” IEEE transactions on Software
agriculture to improve livelihoods and environmental quality in poor
engineering, vol. 24, no. 11, pp. 908–926, 1998.
countries,” Irrigation and Drainage, vol. 54, no. S1, 2005.
[31] R. Ali, F. Dalpiaz, and P. Giorgini, “A goal-based framework for con-
[8] T. Asano and A. D. Levine, “Wastewater reclamation, recycling and textual requirements modeling and analysis,” Requirements Engineering,
reuse: past, present, and future,” Water Science and Technology, vol. 33, vol. 15, no. 4, pp. 439–458, 2010.
no. 10-11, pp. 1–14, 1996. [32] U. of Trento, “Constrained goal modeling and reasoning tool- user
[9] J. H. Ensink, W. Van Der Hoek, Y. Matsuno, S. Munir, and M. R. Aslam, manual for cgm-tool version 1.0.0,” 2016.
Use of untreated wastewater in peri-urban agriculture in Pakistan: Risks [33] W. K. Al-Zubari, “Towards the establishment of a total water cycle
and opportunities. IWMI, 2002, vol. 64. management and re-use program in the gcc countries,” Desalination,
[10] A. S. H. Al Amimi, M. A. Khan, and R. Dghaim, “Bacteriological vol. 120, no. 1, pp. 3–14, 1998.
quality of reclaimed wastewater used for irrigation of public parks in the [34] S. Y. Jasim, J. Saththasivam, K. Loganathan, O. O. Ogunbiyi, and
united arab emirates,” International Journal of Environmental Science S. Sarp, “Reuse of treated sewage effluent (tse) in qatar,” Journal of
and Development, vol. 5, no. 3, p. 309, 2014. Water Process Engineering, vol. 11, pp. 174–182, 2016.
[11] G. Al-Nakshabandi, M. Saqqar, M. Shatanawi, M. Fayyad, and H. Al- [35] H. Farzaneh, J. Saththasivam, K. Loganathan, O. Ogunbiyi, S. Sarp,
Horani, “Some environmental problems associated with the use of and G. McKay, “Reuse of treated sewage effluent (tse) in qatar and its
treated wastewater for irrigation in jordan,” Agricultural Water Man- impact on sustainability and the environment,” QScience Proceedings,
agement, vol. 34, no. 1, pp. 81–94, 1997. vol. 2016, no. 4, p. 40, 2016.
[12] N. Khouri, J. M. Kalbermatten, C. R. Bartone et al., Reuse of wastewater
in agriculture: A guide for planners. UNDP-World Bank Water and
Sanitation Program, World Bank, 1994.
[13] W.-W. Li, H.-Q. Yu, and Z. He, “Towards sustainable wastewater
treatment by using microbial fuel cells-centered technologies,” Energy
& Environmental Science, vol. 7, no. 3, pp. 911–924, 2014.
[14] N. R. Mizyed, “Challenges to treated wastewater reuse in arid and semi-
arid areas,” Environmental science & policy, vol. 25, pp. 186–195, 2013.
[15] D. J. Van Rooijen, T. W. Biggs, I. Smout, and P. Drechsel, “Urban
growth, wastewater production and use in irrigated agriculture: a com-
parative study of accra, addis ababa and hyderabad,” Irrigation and
Drainage Systems, vol. 24, no. 1-2, pp. 53–64, 2010.
[16] TheNational, “Treated wastewater being used to irrigate food
crops across abu dhabi, accessed online april 17, 2017. available
at http://www.thenatioanl.ae/news/uae-news/environment/treated-waste-
water-being-used-to-irrigate-food-crops-across-abu-dhabi,” 2013.
[17] C. M. Nguyen, R. Sebastiani, P. Giorgini, and J. Mylopoulos, “Multi-
objective reasoning with constrained goal models,” Requirements Engi-
neering, pp. 1–37, 2016.
[18] W. H. Organization et al., Quantitative risk assessment of the effects of
climate change on selected causes of death, 2030s and 2050s. World
Health Organization, 2014.
[19] S. Hagemann, C. Chen, D. Clark, S. Folwell, S. N. Gosling, I. Had-
deland, N. Hannasaki, J. Heinke, F. Ludwig, F. Voss et al., “Climate
change impact on available water resources obtained using multiple
global climate and hydrology models,” Earth System Dynamics, vol. 4,
pp. 129–144, 2013.
[20] B. Jiménez and T. Asano, “Water reclamation and reuse around the
world,” Water reuse: an international survey of current practice, issues
and needs. IWA, London, pp. 3–26, 2008.
[21] L. Bernstein, P. Bosch, O. Canziani, Z. Chen, R. Christ, and K. Riahi,
IPCC, 2007: climate change 2007: synthesis report. IPCC, 2008.
[22] L. Raschid-Sally and P. Jayakody, Drivers and characteristics of
wastewater agriculture in developing countries: Results from a global
assessment. IWMI, 2009, vol. 127.