An Evaluation of the Transition from Linear Economy to Circular Economy

Abstract

The agriculture sector and food industry have always been essential sectors of the economy and countries. Factors such as limited resources in the face of a growing population as well as climate change and even the COVID-19 pandemic, and between Russia with Ukraine conflict have maximized the strategic importance of the agro-food industry on a global scale. Since it is a global issue affecting almost every country adversely, especially the fight against climate change requires institutional establishment of international cooperation. The aim of this study is to evaluate the current dynamics of existing economic theories and economic models, highlighting the transition from linear economy to circular economies. To do this, the concept of the circular economy and the economy is discussed in relation to the SDGs to better understand the problem. To evaluate the transition from a linear economy to a circular economy, again, the sustainability publications were searched using bibliometric methods. Mostly four concepts related to sustainability, sustainability and rural development, circular economy, and green economy were analyzed by using VOSviewer software. These four concepts are closely associated with sustainability.

1. Introduction

With its vital functions for humanity, the agro-food industry has always been an essential sector of the economy. Factors such as limited resources in the face of a growing population as well as climate change and even the COVID-19 pandemic have maximized strategic importance to the agricultural industry on a global scale, thus the sustainability of development and rural life.

Sustainability stands out as a concept whose frequency of use is constantly increasing in academic literature and socioeconomic life and which remains to be one of the major agenda items because it represents an important approach to the future of the world, humanity, and the ecosystem. With its respective methodology in almost all fields, sustainability has been considered a go-to approach for the earth.

International agreements based on sustainability have been concluded in order to leave a habitable planet to future generations, given the adverse impact of the global climate change. In this context, in September 2000, the United Nations announced the Millennium Development Goals (MDGs) consisting of eight items, highlighting “eradication of extreme poverty and hunger” as the first goal. The remaining seven goals are as follows: promote gender equality and empower women; reduce child mortality; improve maternal health; combat HIV/AIDS, malaria and other diseases; ensure environmental sustainability; and develop a global partnership for development [1].

Later, the Millennium Development Goals were restructured in 2015, increasing the number of goals to 17. The first two goals among the Sustainable Development Goals (SDGs) announced by the UN in 2015 are no poverty and zero hunger. The SDGs went into effect in January 2016 and will guide UNDP’s policies and financing until 2030. UNDP, the leading development agency of the United Nations, represents a crucial potential for the implementation of these goals as it carries out its operations in more than 170 countries and regions. Although sustainability has not dominated all sectors in all of the 17 goals of the UN, efforts are underway to be successful at the international level. In particular, some important studies and applications need to be carried out in the field of combating inequality and injustice, especially to “eradicate extreme poverty (no poverty and zero hunger)” on a global scale. Note that the sustainability of rural life and production in rural areas, which is still of vital importance for food production, and thus the increase in welfare in rural areas remain to be major political agenda items [2]. To achieve the Sustainable Development Goals, the UN Development Programme (UNDP) needs the involvement of governments, the private sector, civil society, and citizens. However, unfortunately, it seems that it will not be possible to achieve these goals until 2030 due to the impacts of the COVID-19 pandemic.

It is clear that it concerns all countries and industries. Therefore, it is no doubt that it would be appropriate to relate the SDGs to the current realities of sustainable development.

2. Development, climate change, and agricultural policies

The position of communities in the development process can be defined to a significant extent by sociocultural, environmental, and economic indicators. Undoubtedly, the initial phase of the social and economic development of humanity was dominated by rural and agricultural production. The transition from this initial phase, namely, agrarian society, to industrial society was not easy, whereas the transition from industrial society to information society has been far more complicated. The transition from agrarian society to industrial society began in the second half of the 18th century when the steam engine was invented and started to be used as a source of energy. Therefore, in the last two centuries, there has been a rapid industrialization process with the use of electrical energy in all fields, including agriculture, following the advent of new inventions, especially steam-powered machines that convert potential energy into kinetic energy [3].

This process has led to great changes in the settlement areas of the communities around the world, particularly in developed industrial societies. Skyrocketing population growth has brought with it urbanization and new economic activities, resulting in alteration and diversification of consumption patterns. This, in turn, has increased the pressure on the environment and natural resources and the rapid development process has led to new social and environmental challenges.

Even the projections for the world population keeping on rising and reaching 10 billion by 2050 entail expansion of food production on a global scale. According to the estimations of the Food and Agriculture Organization (FAO) of the United Nations, the global demand for food needs to be increased by 70% by 2050. Hence, would require raising overall food production by some 70% between 2005/2007 and 2050 [4] related another study; the total global food demand is expected to increase by 35 to 56% between 2010 and 2050, while the population at risk of hunger is expected to change by −91 to +8% over the same period. Moreover, if climate change is taken into account, the ranges change slightly (+30 to +62% for total food demand and − 91 to +30% for the population at risk of hunger) but with no statistical differences overall [5]. As shown, the anticipated changes will be so great that they will affect the settlements, lifestyles, and production and consumption systems.

The fact that all these challenges threaten human life and our planet at a global scale and the threats of climate change and global warming have made the agricultural industry central to life and production sectors. Considering it from the perspective of climate change, it is expected that global warming will lead to global temperature increases every year, resulting in extinction of one quarter of (or more than 1 million) plant and animal species [6] by 2050. According to the United Nations Intergovernmental Panel on Climate Change (IPCC) report, each country will be affected by global climate change at varying levels [7]. This is why the issue of global warming has been addressed not only conceptually, but also concretely by governments, economic sectors, and communities. In this context, the UN Framework Convention on Climate Change (UNFCCC) was adopted in 1990, through which the signatory countries agreed to reduce the emissions of carbon dioxide and other greenhouse gases [8].

Considering the climate change projections, the risks posed by global climate change entail measures for increasing production and productivity in the face of population growth as well as the development of novel technologies and production systems based on adaptation to increases in temperature [3]. In this framework, R&D and technology policies and research and extension (R&E) policies need to be highlighted.

As is known, worldwide experience shows that new technologies have been the driver of social and economic development. As shown in Figure 1, “Cumulative Adoption of Technology” refers to the sum of all countries. Generally speaking, countries compete to take, use and utilize the technology by their own means (locally) or under the influence of international scientific research. Naturally, countries’ ability to produce technology and adoption of innovations lead to faster utilization of the positive effects of such technologies, but not all countries have the capacity to develop and transfer from outside and uphold the technologies they need [9]. Therefore, it is necessary to define a new approach in which the technologies produced for climate change are considered, in a sense, the “common property of humanity” for countries that are unable to produce or transfer technology and have no means to compete with others. It is a fact that the creation of such a culture of sharing will serve all of the 17 Sustainable Development Goals set forth by the UN. So, in order to reduce the effects of climate change, which is a global threat to the earth, it will be important that the UN develops a mechanism that will ensure the exchange of existing and new technologies to be developed among countries, regardless of their ability to produce technology.

Figure 1.

Processes and factors determining the direction of change in development and technology.

It is clear that the global climate change will disrupt the current balances, resulting in adverse impacts on the sustainability of agro-food industry and rural development. Hence, the UN specifically addresses this issue in its SDG 13 (Take urgent action to combat climate change and its impacts) and highlights SDG 17 (Partnerships for the goals: Strengthen the means of implementation and revitalize the global partnership for sustainable development) as a solution [2]. Since it is a global issue affecting almost every country adversely, the fight against climate change requires institutional establishment of international cooperation.

3. Conceptual history of sustainability

In academic circles, there is agreement that sustainable development requires simultaneous improvement of environmental, social, and economic outcomes [10]. Overall, sustainable development takes a global and long-term perspective for a prosperous, just, and secure future [11]. Sustainability science has been defined as “an emerging field of research dealing with the interactions between natural and social systems, and with how those interactions affect the challenge of sustainability. Sustainability is one of the most used concepts in almost every field today. This situation is related to today’s global and local conditions. Here, we look at the historical background of the concept and discuss the current situation. The derivation of technical and academic terms and concepts relates to a use, application or invention. When concepts express approaches, they reflect deeper content, so is the concept of sustainability [10].

Looking at the past, it can be predicted that there were practices within the scope of sustainability in different civilizations in the past centuries, although they do not exactly overlap with today’s terminology and content. This area is a subject of a separate study, and it is possible to find various examples that can inspire today when researched. However, when the available sources are examined, the first use of the term and concept of sustainability dates back to the 18th century. Historically, depletion of natural resources is not new and hits renewable resources first. The scarcity of wood was the concern of feudal Europe and led to the introduction of sustainability principles in forest management. It was in order to preserve wood supplies for the Kingdom of Saxony where in 1713 it was for the first time clearly formulated that forestry had to be “sustainable”, which meant that logging and reforestation had to be in balance. Similar concepts arose in France and Japan [12].

In the same sense as today’s literature, the term “sustainability” itself was used for the very first time in 1953 by JL. Fisher [13, 14]. However, as an original idea “limits to growth”, which underlies the whole concept of sustainability and sustainable development, and which would later take the form of the contemporarily well-known multidimensional sustainability idea, was expressed much earlier by Malthus’s population growth theory, in the end of the 18th century. The United Nations Conference on the Human Environment was an international conference convened in 1972, and brought the industrialized and developing nations. It was the UN’s first major conference on international environmental issues and marked a turning point in the development of international environmental politics [15]. The present and modern understanding of this concept have been though fully and explicitly articulated for the first time in 1987, within the frame of the so-called Brundtland Report on Sustainable Development, which is sometimes termed shortly “Our Common Future”. As the term sustainability is considered not only a scientific idea, but a moral value, a normative goal based on this value, and a pathway for the international policy or social movements as well [14]. Generally in its most widespread perception, sustainability is defined as “a development that meets the needs of the present without compromising the ability of future generations to meet their own needs” [11]. In this context, sustainability stands out as a concept whose frequency of use is constantly increasing in academic literature and socioeconomic life and which remains to be one of the major agenda items because it represents an important approach to the future of the world, humanity, and the ecosystem.

So, the concept of sustainability has been in use for more than three centuries. Therefore, after emerging out of necessity, it has made its way to today’s lexicon, getting enriched in content and being used in conjunction with different concepts.

4. Towards sustainability and circular economy

During the industrial revolution, the increasing demand for inputs and the production factors put into commercial use paved the way for the development of economics and new economic models. The journey that started with the classical economics still continues. However, in addition to factors such as the scarcity of resources, challenges related to resource utilization efficiency, misuse of natural resources, limitedness of production factors and unjust distribution of resources, threats such as climate change have also paved the way for discussions around new models as an alternative to linear economy. This has, in a sense, rendered the SDGs central to sustainability discussions, and the developments that support the SDGs, such as the green economy, circular economy, and bioeconomy have become popular narratives in macro-level sustainability discussions in policy, scientific research, and business. The 17 Sustainable Development Goals set forth by the United Nations in 2015 have renewed a global vision to address sustainability challenges and emphasized the urgency for concerted efforts by multiple societal actors. Over the past decades, “[s]ustainability science” has attracted tens of thousands of researchers, practitioners, knowledge users, teachers, and students from diverse institutions and disciplines from across the world [16]. However, circular economy (CE) is currently a popular concept promoted by the EU, by several national governments and by many businesses around the World [17]. Therefore, the process of change that we have experienced demonstrates the UN will play a key role in achieving the Sustainable Development Goals. According to Velenturf and Purnell [10], economic growth is still part of the goals, e.g., SDGs 8 and 9, which relate economic growth to resource efficiency, and the main mechanism proposed to achieve a balance is through decoupling. SDG 12 does not mention circular economy literally, but it does cover the sustainable management and efficient use of natural resources, reducing and preventing wastes, uptake of reuse etc., and changes in lifestyles, procurement policy and business reporting, all of which are closely aligned with circular economy principles. Targets under sixteen out of the seventeen SDGs are related to a circular economy (Figure 2).

Figure 2.

Circular economy can enable a significant number of targets under the UN sustainable development goals (legend: Fraction of targets under each goal that would be strongly (red) and partially (orange) enabled by the implementation of circular economy measures).

However, the circular economy can contribute positively to most of the sustainable development goals, but sustainable development and circular economy are on diverging pathways. While the sustainable development agenda puts people front and center with economic prosperity recognized as a means for living fulfilling lives in harmony with nature, circular economy remains fixated on technological solutions, the implementation of which is driven by a promise of traditional economic growth. Circular economy also must be fully integrated with sustainable development. Circular economy should be understood as an emerging practical ideology that lacks an evidence-based theoretical framework to guide implementation. It lacks an economic theory that can pragmatically guide the transition from the prevailing neoclassical model toward one that would drive the transition toward a sustainable circular economy and be palatable for governments. The critique on circular economy should be understood as much as a critique on sustainable development itself, and both require research and constant learning to ensure progress towards sustainability [10]. It is an inevitable necessity to manage the process taking into account the contribution of local and international cooperation efforts to sustainability.

As is known, circular economy is an economy constructed from societal production-consumption systems that maximize the services produced from the linear nature-society-nature material and energy throughput flow. This is done by using cyclical materials flows, renewable energy sources and cascading¹-type energy flows. Successful circular economy contributes to all three dimensions of sustainable development. Circular economy limits the throughput flow to a level that nature tolerates and utilizes ecosystem cycles in economic cycles by respecting their natural reproduction rates [17].

Previous research shows that Circular Economy (CE) is a concept that stems from the need to address environmental degradation, social unrest and inequalities, institutional instability, resource scarcity, and economic challenges caused by the linear nature-society-nature systems that a large portion of society operates on [18]. In this framework, the acceptance of circular economy on a global scale gives rise to a need for novel technologies such as renewable energy generation technologies, which will be among the major topics of discussion in the medium term. It would be appropriate to explore academic research to clarify this issue. The following sections deal with the extent to which topics such as sustainability, green economy, and circular economy are addressed and what other topics are highlighted in scientific research and publications. It is of particular importance in that it shows the direction of change in scientific studies with respect to the concepts in the specified fields. Therefore, a bibliographic assessment of sustainability is provided below.

5. An assessment of sustainability approach

Bibliometric analyses provide a big and profound picture of the current knowledge base. Also known as science mapping, bibliometric analyses have been applied in a variety of fields and disciplines. However, studies on the concepts of circular economy and sustainability are also being conducted. Therefore, this section analyses the global knowledge base on sustainability and new concepts associated with it.

The concept of sustainability has been used continuously in academic literature and socio-economic life on a global and local scale since the day it was introduced. Pollution and the threat of global climate change, especially as a result of industrialization, led to controversies surrounding classical economics and the search for alternative methods. In this context, they paved the way for the emergence of circularity-based concepts and approaches as an alternative, such as green and blue economies. To provide a better understanding of this development process, the concepts of sustainability, green economy, circular economy, and green deal are addressed.

6. Material and methodology

In the bibliometric analysis, VOSviewer was used to retrieve the publications on sustainability. VOSviewer is a software tool for constructing and visualizing bibliometric networks. At the same time, it can be used to construct maps of authors or journals based on co-citation data or to construct maps of keywords based on co-occurrence data [19, 20]. To identify the most commonly used themes associated with the theme of the research, an analysis of the networks was conducted based on the keywords. There are several network techniques used for this purpose. Among them, researchers usually employ methodologies based on distance, graphs, and timelines [21]. Keywords refer to the basic concepts used in a study. They are the core and essence of a document, which is a high-level summary of the article content [22]. In this paper, the bibliometric data come from Scopus, one of the world’s leading academic databases. What is conducted here is network of fractional order research on the scientific literature concerning sustainability, green economy, and circular economy. The figure shows the distribution of hot keywords in fractional order research, and different colors in the figure represent different clusters of research hotspots. Figures are mainly composed of nodes and connecting lines. The larger the keyword node, the higher the frequency of occurrence, and the thicker the line between nodes, the higher the co-occurrence frequency. Moreover, the distribution of the distance between nodes is positively correlated with the relevance of keywords [23]. Accordingly, the analysis of the keywords provides strong data about the content of the subject discussed in the research articles.

7. Bibliometric analysis of keywords

7.1 The concept of sustainability with related main keywords

A keyword search carried out on the subject of “TITLE-ABS-KEY (sustainability)” generated almost 286,025 keywords in the Scopus database. From this database, by specifying exclusively the articles, a collection of 188,662 documents was listed using the command TITLE-ABS-KEY (sustainability) AND (LIMIT-TO (DOCTYPE, “ar”). Finally, from this list of articles, the first 2000 articles were considered for keyword analysis. VOSviewer was used to generate the keyword maps. Figure 1 below shows all the keywords according to the topics covered in this presentation.

As shown in Figure 3, the major concepts found to be associated with the concept of sustainability in the articles published between 2015 and 2017 include keywords such as corporate sustainability, sustainability assessment, sustainability indicators, sustainability reporting, urban sustainability, higher education, sustainability education, life cycle sustainability, energy, decision making, and sustainability criteria. In addition, new concepts such as COVID-19, firm performance, organizational sustainability, theory building, waste, and bio-based products have been commonly used in 2020s. It suggests that the research on sustainability keeps on developing by deriving new concepts.

Figure 3.

Sustainability main keywords based on Scopus data.

7.2 The concepts of sustainability and rural development with related main keywords

For “Sustainability and Rural Development”, the same collection procedure was used. A document search was carried out in the Scopus database. The finding was 7047 documents from which almost 5179 documents were extracted by the following command: TITLE-ABS-KEY (sustainability AND rural AND development) AND (LIMIT-TO (DOCTYPE, “ar”)). Among these articles, the first 2000 were selected for analysis. A total of 5169 keywords were counted, with a minimum occurrence of one. The graph above presents the occurrence of keywords by year. Thus, words that have made up the lexical field of the topic before 2010 (environment, climate, biodiversity, etc.) are colored darker. The recent keywords are colored yellow (agritourism, circular economy, etc.). The keywords’ importance is measured by the size of the diameter of their circle. The larger the circle is, the more the keyword is used. Sustainability appears to be the most used keyword with a larger diameter. Table 1 shows the top ten keywords for this category.

Topics	Sustainability	Sustainability and rural development	Circular economy	Green deal
Keywords	Sustainability; Sustainability assessment; Sustainable development; Sustainability indicators; Corporate sustainability; Social sustainability; Environmental sustainability; Sustainability reporting; Economic sustainability; indicators	Sustainability; Rural development; Sustainable development; Rural tourism; Rural areas; China; Rural; Agriculture; Development; Rural electrification	Circular economy; Sustainability; Sustainable development; Recycling; Waste management; Industry 4.0; Resource efficiency; Waste; Business model	Green economy; Sustainable development; Circular economy; Sustainability; Green growth; Climate change; Renewable energy; Environment; Green jobs; China

Table 1.

Top keywords according to the topics.

The analysis shows what concepts are most widely used by publications in which years (Figure 4). Accordingly, the major concepts used in association with the concept of “sustainability and rural development” in the articles published between 2015 and 2017 include keywords such as sustainability, rural development, sustainable development, rural tourism, rural areas, China, rural, agriculture, development, rural electrification, regional development, India, social sustainability, sustainability assessment climate change, agricultural sustainability, sustainable tourism, and food security. Furthermore, concepts such as SDGs, agritourism, ecotourism, sustainable development goals, smart village, loyalty, and landscape pattern have been introduced in the 2020s. It suggests that the research on sustainability and rural development keeps on developing by deriving new concepts.

Figure 4.

Sustainability and rural development.

7.3 The concepts of circular economy with related main keywords

A keyword search on the circular economy was conducted through 15,098 documents retrieved by the string TITLE-ABS-KEY (circular AND economy). The Scopus database was used to collect the large number of keywords. A random selection of 2000 words was made from nearly 9606 documents generated by the search TITLE-ABS-KEY (circular AND economy) AND (LIMIT-TO (DOCTYPE, “ar”)). On this basis, and with the assistance of VOSviewer, the keyword map depicted above was generated. The top keywords include circular economy sustainability, sustainable development, recycling, waste management, industry 4.0, resource efficiency, waste, and business model (Figure 5 and Table 1).

Figure 5.

Mapping the circular economy with main keywords based on Scopus data.

The analysis shows what concepts are most widely used by publications in which years (Figure 5). The major concepts used in association with the concept of circular economy in 2019 include circular economy, sustainability, sustainable development, recycling, waste management, industry 4.0, resource efficiency, waste, business model, linear economy, and environment. Moreover, concepts such as industry 4.0, Covid-19, digital twin, posthumanism, food supply chain, circular cities, and goals were used in association with the concept of circular economy. It is important in that it shows the new concepts that are increasingly used in association with circular economy are the topics of scientific research.

Figure 6 shows the frequency of use of the keywords when circular economy is selected as the main concept. Accordingly, the top six concepts that are most used with circular economy are sustainability, sustainable development, recycling, waste management, industry 4.0, and resource efficiency In addition, other related keywords that are used with it, including in the studies discussing linear economy, are also given. The period in which other keywords are used with circular economy is again 2015–2021. What we see here is that the top five keywords that are most used with circular economy are in the period 2018–2021. The keywords that are often used with circular economy as of 2020 include resource efficiency, business models, reverse logistics, industrial symbiosis, and zero waste. It is important in that it provides information about the topics of new research.

Figure 6.

Annual occurrence of relevant keywords.

7.4 The concept of green economy with related main keywords

A total of 8191 documents were listed by the search TITLE-ABS-KEY (green AND deal) on Scopus database. By searching only articles, 5036 articles were listed. VOSview helps to generate the network of keywords. The most used keywords are in Figure 5 below. The period from 2016 to 2018 seems to be the one where the keyword “green deal” was most used. To date, it is the most used keyword given its size through the node. The network represents this period in green color for nodes (Figure 7).

Figure 7.

Green deal-related keywords’ network.

With regard to what concepts are most used in which years (Figure 5), the analysis shows that the keywords that are most used with the concept of green economy in 2014–2015 include low-carbon economy, green chemistry, green supply chain, green building, green economics, atom economy, well-being, and Rio + 20. Among the other major concepts used in conjunction with the concept of green deal in the period 2016–2018 are keywords such as green economy, sustainable development, circular economy, sustainability, green growth, climate change, renewable energy, environment, green jobs, and China. Moreover, concepts such as green economic efficiency, pollution, Russia, Croatia, ports, lifelong learning, spatial econometric model, regional cluster, and green reagents have been widely used in the 2020s. It is important in that it shows the number of studies involving new concepts related to the concept of green deal and their frequency of use has increased.

8. From linear economy to circular approaches

Rising demand for food on a global scale remains to be a challenge due to the increase in world population. However, factors such as global climate change and the COVID-19 pandemic as an extreme threat have led to a strong perception of the importance of agricultural production by all societies. It is understood that the demand for agricultural products that are healthy, high in nutritional quality and produced in an environment-friendly manner will increase gradually.

Today, development policies at the international level are focused on sustainability. They are usually aimed at establishing the conditions that will ensure the sustainable use of resources and the sustainability of human life in the future. Efforts are underway to end poverty and improve and expand fundamental rights and freedoms by reducing welfare differences between countries and between segments of societies, especially through the adoption of a sustainability approach on a global scale [24].

9. Evaluation of the top keywords according to the topics

The results of the conceptual analysis are given in Table 1. Accordingly, the four concepts that are addressed here are closely associated with sustainability. All of the keywords related to sustainability are accompanied by the concept of sustainability. The analyses carried out concerning the concepts of sustainability and rural development, circular economy, and green deal involve the concept of sustainability twice for each of them. It is important in that it shows the concept of sustainability continues to be used in conjunction with emerging concepts. It suggests that although new concepts are derived and new approaches are put forth, the concept of sustainability maintains its place in the literature.

While the ‘take-make-dispose’ model suggested by the classical economics (i.e., linear economy) has dominated all economies for the last two centuries, the sustainability approach has always existed despite the fact that it does not fit well with the assumptions of classical economics and its level of effectiveness is low.

Accordingly, the linear “take-make-dispose” model relies on large quantities of easily accessible resources and energy, and as such is increasingly unfit for the reality in which it operates. Working towards efficiency alone—a reduction of resources and fossil energy consumed per unit of manufacturing output—will not alter the finite nature of their stocks but can only delay the inevitable [25]. As is known, circular economy, as opposed to the current linear economy, can be seen as a sustainable economic system where economic growth is decoupled from resources use, through the reduction and recirculation of natural resources. The circular economy concept attracts increasing attention of governments, scholars, companies, and citizens as a necessary step to achieve sustainable development [26]. Again according to The Ellen MacArthur Foundation [25], the circular economy draws a sharp distinction between the consumption and use of materials: circular economy advocates the need for a “functional service” model in which manufacturers or retailers increasingly retain the ownership of their products and, where possible, act as service providers—selling the use of products, not their one-way consumption. This shift has direct implications for the development of efficient and effective take-back systems and the proliferation of product and business model design practices that generate more durable products, facilitate disassembly and refurbishment, and where appropriate, consider product/service shifts. As circular economy thinker Walter Stahel explains, “The linear model turned services into products that can be sold, but this throughput approach is a wasteful one. In the past, reuse and service-life extension were often strategies in situations of scarcity or poverty and led to products of inferior quality. Today, they are signs of good resource husbandry and smart management.” As a result, circular economy is also an industrial system that is restorative or regenerative by intention and design. It replaces the “end-of-life” concept with restoration, shifts towards the use of renewable energy, eliminates the use of toxic chemicals, which impair reuse, and aims for the elimination of waste through the superior design of materials, products, systems and, to develop within this, business models.

Again, considering the European Green Deal (EGD), it is clear that at the heart of the main components of the Deal is the aim of transforming the EU economy for a sustainable future. In line with this, the EGD is intended to reduce greenhouse gas emissions within a certain program in order to make the EU climate-neutral by 2050. In order to reduce carbon leakage from the EU, efforts are underway to develop a new system built with new taxes and non-tariff barriers in trade through the border carbon adjustment (BCA) mechanism. Again, by 2030, the EU aims to transform 25% of the agricultural lands in its territories into organic farming land. Organic production in the fresh fruit and vegetable industry and dried and frozen products industry is expected to increase in the coming years. In addition, organic products will be in demand in other agricultural product markets such as medicinal and aromatic plants and mushrooms, so plans are being made to ensure product safety. Another important aspect of the European Green Deal is that it gives priority to energy saving and renewable energy sources. In general, renewable energy sources such as solar energy are supported. The Green Deal also aims to increase the amount of fruit and vegetable consumption in human nutrition by regulating the consumption habits of consumers and combating obesity and diseases such as cancer, thereby eliminating the serious economic burden on the healthcare system [27].

Reaching and indeed exceeding national or EU GHG reduction targets, such as those proposed by the EU Green Deal, is not an easy task. However, many municipalities across Europe are aware of their crucial role and are developing strategies toward carbon neutrality by 2050. The experience of those cities that have already joined the CoM 2030 initiative with ambitious GHG reduction targets could serve as an example for others [28].

The EU countries have taken the lead in the transition to a sustainable food system, and this process will affect many countries. The technical and financial support of the EU instruments such as harmonization funds and the European Agricultural Fund for Rural Development will facilitate this transition.

10. Conclusions

While the journey that started with linear economy still continues, challenges related to resource utilization efficiency, misuse of natural resources, limitedness of production factors as well as threats such as climate change have given rise to discussions around new models as an alternative to linear economy. In particular, circular economy is addressed frequently. Circular economy is a concept that stems from the need to address environmental degradation, social unrest and inequalities, institutional instability, resource scarcity, and economic challenges caused by the linear nature-society-nature systems that the large portion of society operates on [18]. The acceptance of circular economy on a global scale will probably be among the major topics of discussion in the medium term, as there is need for novel technologies such as renewable energy generation technologies.

In this framework, this paper deals with the conceptual developments in academic studies in a bibliometric fashion. It shows that the concepts have both varied and increased. The use of the concepts of sustainability, green economy and circular economy in academic studies has been more widespread. Therefore, it is seen that the process of transition from linear economy to circular economy is supported by academic studies, which derive new concepts that are addressed as further research topics by new studies. In conclusion, it can be said that the process of change in this field will contribute to the achievement of the Sustainable Development Goals of the UN. With the global cooperation efforts that are being carried out and expansion of practices focusing on sustainability, academic studies will play a key role in, and accelerate, the transformation in question.