Smart Cities and Urban Areas—Aquaponics As Innovative Urban Agriculture

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Urban Forestry & Urban Greening 20 (2016) 402–406

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Urban Forestry & Urban Greening

j ournal homepage: www.elsevier.com/locate/ufug

Smart cities and urban areas—Aquaponics as innovative urban agriculture

∗

Maria José Palma Lampreia dos Santos

ESCS - IPL and DINÂMIA’ CET-ISCTE - University of Lisbon, School of Communication and Media Studies, Campus de Benﬁca do IPL 1549-014 Lisboa, Portugal

a r t i c l e i n f o a b s t r a c t

Article history: Aquaponics is an innovative smart and sustainable production system for integrating aquaculture with

Received 4 May 2016

hydroponic vegetable crops, that can play a crucial role in the future of environmental and socio-economic

Received in revised form 5 August 2016

sustainability in smart cities. These cities aim mobilize all knowledge centers and Information and Com-

Accepted 10 October 2016

munication Technologies (ICT) into innovation hubs in order to strengthen the socio-economic progress.

Available online 13 October 2016

Nowadays the production, transport and logistics of food requires high costs and transport and harvest

from other parts of the planet to the cities, associated to intensive polluting technologies. Aquaponics can

Keywords:

play a key role enabling local production, fresh, free of pesticides and healthy with short supply chains

Data envelopment analysis

Efﬁciency in the cities.

Despite the technical developments in aquaponics there is still no integrated approach to analyze

Smart sustainability

Typologies of aquaponics their potential as urban agriculture. This paper aims to contextualize the aquaponics as urban farming

Urban innovative agriculture and analyze the necessary developments in that ﬁeld, namely, the need of an integrated approach from

producers to consumers on smart cities.

So, this paper analyzes the importance of Theory of Planned Behavior on aquaponics stakeholder’s deci-

sion making process and the efﬁciency analysis in aquaponics systems by parametric (Data Envelopment

Analysis), and non-parametric methods (stochastic frontier production) as an integrated and innovative

approach.

1. Introduction ative activities and sustainability-oriented initiatives (Kourtit et al.,

2012; Shapiro, 2006).

Smart cities are known not only from a technological point of At the urban areas since the pioneering work of Krugman (1998),

view, but also for its economic, social and environmental sustain- new economic geography has been developed and sophisticated in

ability. Smart cities aim to mobilize all knowledge centers and several directions in order to show how the spatial distribution

information and communication technologies (ICT) into innova- of economic activities is evolving in the real world (Tabuchi, 2014;

tion hubs in order to strengthen the socio-economic progress in Head and Mayer, 2004). There is consensus that while regional pop-

EU Member States and around the world. The validity of any city’s ulations were dispersed in early times, there has been, in recent

claim to be smart has to be based on something more than its use years, a growing rural exodus causing the cities’ population to

of ICTs (Hollands, 2008; Allwinkle and Cruickshank, 2011). Nowa- increase considerably, according to Tabuchi (2014).

days, smart city represents a paradigm of a forthcoming future that The year 2007 marked an important development in the history

will change – or is changing – a citizen’s life without possibility to of urban cities because, for the ﬁrst time, the share of total popula-

go backward (Luvisi and Lorenzini, 2014). Smart cities are a pol- tion living in cities exceeded 50%. Urbanization has become a major

icy concept in Europe designed to mobilize all knowledge centers global trend, with ever increasing degrees of urbanization reaching

into innovation hubs in order to strengthen the socio-economic 70% and more in various European and Asian countries (Kourtit

progress in EU Member States. Smart cities have a high productiv- et al., 2012). Increasing urbanization of cities is accompanied by

ity as they have a relatively high share of highly educated people, network support systems from infrastructure, transport networks

knowledge-intensive jobs, output-oriented planning systems, cre- and logistics, a greater demand for food and for food transportation

associated to long supply chains, communication, trade, cultural

aspects, tourism and employment, generating spillovers and lead-

∗ ing to growth and development of cities (Leamer and Storper,

Corresponding author.

2014).

E-mail addresses: [email protected], [email protected]

http://dx.doi.org/10.1016/j.ufug.2016.10.004

M.J.P.L. dos Santos / Urban Forestry & Urban Greening 20 (2016) 402–406 403

Simultaneously, urbanization also implies a transformation of 3. The importance of theory of planned behavior (TPB) on

the rural environment that was strongly marked since the indus- aquaponics stakeholder’s decision making process

trial revolution, in so far as gradually arable land for agriculture

and forests decreased to be used for urban and industrial use. In The model Theory of Planned Behavior (TPB) (Ajzen, 1985, 1991,

parallel, the individual cities and countries from an economic point 2012), is based on the assumption that individuals often behave

of view have become increasingly globalized due to the needs of rationally taking into account available information, and implicitly

international trade and ﬁnancial needs (Mrak, 2000). Examples or explicitly taking into account the implications of their actions.

of governance and management practices to promote urban tree The social component has a marked impact on individual deci-

diversity exist globally (Morgenroth et al., 2016). sions. The model assumes that behavior that leads to the intention

Cities are becoming smart not only in terms of the way we can of performing certain actions is determined by three independent

automate routine functions serving individual persons, buildings, predictors of intention: attitude, subjective norms and perceived

trafﬁc systems but in ways that enable us to monitor, understand, control (Ajzen, 2002).

analyze and plan how the city can improve its efﬁciency, equity The individual component is based on a person’s attitudes,

and the life quality of its citizens, all of this in real time (Batty et al., where an attitude is a disposition to respond favorably or unfavor-

2012). According to Lindholst et al. (2016) the central question in ably to an object, person, institution or event (Kim and Hunter 1993;

contemporary: What would an urban green space be like? Dos Santos et al., 2010). The relative contribution of attitudes and

As a result, this authors propose a new scheme which derives subjective norms vary according to the socio-economic environ-

from three main factors, structural and general aspects, function- ment conditions where a person resides. Attitudes are determined

ality and experience along with management and organization, as by beliefs about the performance results of the behavior and the

three principal themes and provides an easily manageable, uniﬁed evaluation of results (Dos Santos et al., 2010). Attitudes towards

and affordable approach to assessment of a variety of urban green a particular behavior are based on beliefs about outcomes of that

spaces (Lindholst et al., 2016). behavior and an evaluation as to whether such outcomes are per-

Nowadays the world is facing a number of serious problems such ceived as good or bad (Dos Santos et al., 2010; Iraizoz et al., 2007).

as population rise, climate change, soil degradation, water scarcity The social related component is referred to as the subjective

and food security are among the most important (COST FA1305, norms which are the person’s perceptions of the social pressures

2015). Van den Bosch and Depledge (2015) alert to the urgent need acting on him/her to execute or not to execute the behavior in ques-

of ﬁnding methods for protecting public health from the negative tion (Ajzen and Fishbein, 1980; Dos Santos et al., 2010; Gorton and

effects of climate change. Aquaponics, as a closed loop system con- Davidova, 2007). Subjective norms are independent of the person’s

sisting of hydroponics and aquaculture elements, could contribute own attitude towards the behavior in question, but the inﬂuence of

to address these problems (COST FA1305, 2015). However, there subjective norms on a person will depend on the individual’s will-

is a lack of quantitative research to support the development of ingness to comply with the attitudes of others (Gorton et al., 2008;

economically feasible aquaponics systems. Although many stud- Dos Santos et al., 2010).

ies have addressed some scientiﬁc aspects, there has been limited According Beedell and Rehman (2000) and Dos Santos et al.

focus on commercial implementation. (Goddek et al., 2015). (2010) in the past, the research on agricultural stakeholder’s atti-

Smart cities are also associated with highly skilled and informed tudes, motivations and intentions tended to be subjective, and,

citizens. This suggests the presence of highly informed and theoretically imprecise. Subsequently, through the use of TPB

demanding consumers. As such, when in the presence of innova- a wide range of work comes within the stakeholder’s agricul-

tive, pesticide-free and local products, they may, as expected, prefer tural research that has been used extensively with very accurate

said products. Nonetheless, presently the main attitudes and values assumptions and results. Among this the study of the attitudes

of consumers, face the aquaponics products are not yet known. and intentions of farmers, conducted in Borges et al. (2016) who

identiﬁed key beliefs underlying Brazilian cattle farmers’ intention

to use improved natural grassland; Niles et al. (2015) who ana-

lyzed farmer’s intended and adoption of climate change mitigation

and adaptation strategies. Meijer et al. (2015) analyzed farmerıs´

2. Urban farming and short supply chains in smart cities

attitudes, intentions and behavior forest conservation in Malawi.

Dos Santos et al. (2010) analyzed attitudes of the Portuguese farm-

Aquaponics systems can be set up almost everywhere and have

ers to the Common Agricultural Policy (CAP) and intentions about

the potential to urbanize food production. This could bring impor-

the new irrigation public scheme from Alqueva Irrigation Project

tant socio-environmental beneﬁts. Aquaponics farming plants

at Portuguese Alentejo Region. Micha et al. (2015) analyzed the

could be implemented in old industrial neglected buildings with

role of corruption and farmers’ responses to the ﬁnancial crisis on

the advantages of re-establishing a sustainable activity without

certain areas of Greece. Konijnendijk et al. (2007) assessed and

increasing urbanization pressure on land. (Goddek et al., 2015). So,

did an extensive review of research and research needs in urban

can be solved several problems that currently affect smart cities,

forestry was carried out in urban forestry research and research

which need to be sustainable. On the one hand, the price’s pressures

needs in Nordic and Baltic countries (Denmark, Estonia, Finland,

on the arable land and urban land can reduce, utilizing abandoned

Latvia, Norway and Sweden during 2005).

buildings that already have a lower residential value, and on the

In the context of the attitudes and intentions of the consumers,

other, fresh food will be produced with no environmental contam-

recently, there is also a wide range of works based on TPB which

ination nor long transport cycles and expensive storage from long

analyze the intentions and attitudes of consumers, namely: Wilson

distances. That resulting in short supply chains, with economic,

et al. (2015) identiﬁed behavioral intention as a mediator from

environmental and social beneﬁts, for producers, consumers and

the conscientiousness fruit and vegetable consumption; Paul et al.

inhabitants in general. Similarly, this farming systems can also be

(2016) predicting green product consumption using theory of

a way of creating new jobs in cities, as cities are places where there

planned behavior and reasoned action; Abdul Latiff et al. (2015)

is a huge supply of highly skilled resources which, along with the

who validate the impact of food labels among Malaysian consumers

proximity to ICT technologies, can actively contribute to the cre-

using TPB model. Yadav and Pathak (2016) analyzed the intention to

ation of added value, the evolution of innovation and the generation

purchase organic food among young consumers. Chan et al. (2016)

of spillovers.

used extended TPB to predict the adolescents’ intention to engage

404 M.J.P.L. dos Santos / Urban Forestry & Urban Greening 20 (2016) 402–406

in healthy eating. At a global level Hassan et al. (2015) achieved Two main general approaches have been applied to iden-

a structured review of multi-country TPB studies on consumers’ tify efﬁcient producers: parametric (Data Envelopment Analysis

attitudes. (DEA)), and non-parametric methods (stochastic frontier produc-

However, there has not been any study or literature on the atti- tion (SFA)). (Das and Kumbhakar, 2012; Dos Santos et al., 2015). The

tudes, values and intentions of consumers and residents from smart main difference between the two methods is that the parametric

cities on the acceptability of the aquaponics foods (vegetables and approach requires the construction of a functional medium and test

ﬁsh) as an innovative form of diet in the cities. In this context the hypothesis, taking into account the statistical noise and providing

development of studies on TPB attitudes intentions and values of estimates of the parameters of production factors and elasticities.

consumers from smart and other cities it of paramount importance. But enabling new interpretations imposes a functional form to be

Where research on attitudes and intentions of aquaponics estimated, together with the assumptions about the distribution of

producers is concerned, the situation is not very different from con- the compound error term (Das and Kumbhakar, 2012).

sumers. Presently, only Love et al. (2014) and Love et al. (2015) The literature indicates that both methods have strengths and

analyzed the production methods, experiences, motivations, and limitations, but the choice depends mainly on the most appropriate

demographics of aquaponics by applying a survey to practition- for a particular research question, the nature of the data and main

ers in the United States and abroad. The main conclusions suggest objectives of the work (Das and Kumbhakar, 2012; Dos Santos et al.,

that respondents were most often motivated to become involved in 2015).

aquaponics to grow their own food, for environmental sustainabil- Data Envelopment Analysis (DEA), ﬁrst introduced by Charnes

ity reasons, and for personal health reasons. Also Khan et al. (2016) et al. (1978) and after improvement, is a linear programming tech-

analyzed the fish consumption behavior and fish farming attitude nique that identifies the best-practice decision making units (DMU)

in Kingdom of Saudi Arabia. Nevertheless, the TPB model has never on the efﬁcient frontier and determines the inefﬁciencies for the

been used to understand the attitudes and intentions of aquaponics others in the sample accordingly Thoraneenitiyan and Avkiran

farmers. (2009). The DEA frontier is formed as the piecewise linear com-

Many studies on the technical aspects of aquaponics have binations that connect the set of these best-practice observations,

been developed. Nevertheless, they have not yet analyzed farmer’s yielding a convex production possibilities set (Thoraneenitiyan and

typologies on aquaponics in different regions of the world, from Avkiran, 2009).

urban-rural location, size of their holdings and the main objectives DEA does not require the explicit speciﬁcation of the production

from practitioners, except Love et al. (2014). Aquaponics can coex- function. However, DEA assumes there is no noise in constructing

ist with various typologies of farms from educational purpose to the frontier that temporarily gives DMU a better measured per-

social and competitive holdings. Since all these types can coexist formance over other units. Thus, any error in a unit’s data may be

in smart cities it would be crucial to know and classify aquaponics reﬂected as a change in its measured efﬁciency (Thoraneenitiyan

practitioners and to analyze their sustainability contribution to the and Avkiran, 2009).

smart cities. On the other hand the non-parametric-methods: The stochas-

tic frontier production (SFA) function was ﬁrst proposed by Aigner

et al. (1997), (Coelli, 1996). The original speciﬁcation involved a

4. Deﬁning typologies on aquaponics to capture the

production function speciﬁed for the cross-sectional data that had a

heterogeneity and main goals

term an error that had two components, one to account for random

effects and another to explain technical inefﬁciency. This model can

Typologies are often used to identify, cluster and capture the

be expressed as follows according to Coelli, (1996).

agricultural heterogeneity of the agricultural systems, and can be

Y = x ␤ + V −

achieved by using different approaches and methods (Kuivanen i i ( i Ui) (1)

et al., 2016). Traditionally, that analysis was performed to deﬁne

where i = 1,. . .,N,

the agricultural typologies, as it was used to identify the diversity

And:

and its causes (Gaspar et al., 2008; Tittonell et al., 2015), analyze

Yi is the production (or the logarithm of the production) of the

agricultural trajectories (Iraizoz et al., 2007; Dos Santos et al., 2010;

i-f ﬁrm;

Dos Santos, 2013; Salvioni et al., 2014) or select farms in order

xi is a k × 1 vector of (transformations of the) input quantities of

to improve and implement new technologies or innovation, and

the i-th ﬁrm;

monitoring and analyze the impact of policies or agricultural devel-

␤ is a vector of unknown parameters to be determined;

opment projects (Santos et al., 2011; Andersen et al., 2007).

the Vi are random variables which are assumed to be iid.

The methodological techniques traditionally used on agricul- ␴ 2

N(0, V ), and independent of the

tural farms could be used for aquaponics as an urban agriculture

Ui which are non-negative random variables which are assumed

helping deﬁning goals, clustering and targeting aquaponics sys-

to account for technical inefﬁciency in production and are often

tems in the cities. Also the methodology used in the deﬁnition of 2

assumed to be iid. |N(0,␴U )|. (Coelli, 1996).

farms, can be adjusted to aquaponics. Traditionally this analysis is

The model could be presented as a Cobb-Douglas function if

made, almost consensually through multivariate analysis: factorial

dependent and independent variables are logaritmized (log).

analysis cluster analysis (Dos Santos et al., 2010; Dos Santos, 2013).

At the present both methods are extensively used in different

sectors, industries, countries and more or less aggregated regions

5. Efﬁciency analysis in aquaponics systems or countries efﬁciency in industries or sectors. As well as in agri-

cultural efﬁciency study these techniques are used extensively as

Resulting from the classiﬁcation of aquaponics typologies the well as more technical developments, as second time regression,

study of the aquaponics efﬁciency, mainly in addressing compa- bootstrap procedure, etc. On farms efﬁciency there is a huge devel-

nies intended to market and proﬁt maximization objectives and opment as well: (Mendes et al., 2012; Silva et al., 2013; Guesmi

competitiveness in the markets will also be important. et al., 2015; Khalili-Damghani et al., 2015; Michler and Shively,

The deﬁnition of an efﬁcient frontier function in order to mea- 2015) among others.

sure the performance of production units has been done over time By studying the aquaponics consumers’ attitudes, we will be tak-

by many authors in different sectors, countries and industries (Das ing a leap forward in what regards the efﬁciency measurement, as

and Kumbhakar, 2012; Dos Santos et al., 2015). this variable will provide a way to analyze both sides of the sector’s

M.J.P.L. dos Santos / Urban Forestry & Urban Greening 20 (2016) 402–406 405

externalities, and also the degree of its acceptance to the stake- Das, A., Kumbhakar, S.C., 2012. Productivity and efﬁciency dynamics in Indian

banking: An input distance function approach incorporating quality of inputs

holders and the corrective measures to raise aquaponics as high as

and outputs. J. Appl. Econ. 27 (2), 205–234.

it should and can be.

Dos Santos, M.J.P.L., Henriques, P.D.D.S., Fragoso, R.M.D.S., Da Silva Carvalho,

Firstly, the precise deﬁnition of aquaponics’ exploration typolo- M.L.P.V., 2010. Attitudes of the portuguese farmers to the EU common

agricultural policy. Agric. Econ. 56 (10), 460–469.

gies will allow the measurement of the scale effects of the different

Dos Santos, M.J.P.L., 2013. Segmenting farms in the European Union. Agric. Econ .

typologies during the calculation of aquaponics’ efﬁciency. That

59, 49–57.

is, the aforementioned methodologies emphasize a connection Dos Santos, M.J.P.L., Mendes-Ribeiro, M., Marques, I.A., Pereira, J.M., 2015.

Portuguese airport efﬁciency analysis: the case study of oporto. Mediterr. J.

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Gaspar, P., Escribano, M., Mesías, F.J., de Ledesma, A.R., Pulido, F., 2008. Sheep

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inherent to the different aquaponics explorations.

Thorarinsdottir, R., 2015. Challenges of sustainable and commercial

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