As in other cities in Asian developing countries, organic waste in Hanoi accounts for the largest proportion of the municipal solid waste (MSW). The city produces more than 6500 tonnes of solid waste per day, and the average amount of MSW generated daily per capita is 0.9 kg. It is estimated that by 2020, this figure will have reached 1.4 kg/day [1
]. Its weight is increasing rapidly along with the increase in population and the rapid urbanization process of a city that has been geographically and administratively expanded [2
]. Apart from bad odors and unsightliness, organic waste has also caused serious environmental degradation and negative impacts on public health [3
Utilizing urban waste in agriculture production through composting has been considered as a suitable option to cope with urban waste issues in developing countries [3
]. This alternative may be attributed to economic, environmental, and social factors, such as the costs associated with landfilling and the transportation of waste, the pollution impacts of accumulated solid waste, public health threats, and Not In My Back Yard (NIMBY) conflicts. It further helps to improve the fertility of the soil because of the large amount of organic matter contained in waste streams in these countries [10
]. Aware of not only the threats from pollution, but also the opportunities for recycling organic waste, the government of Vietnam approved the National Strategy for Integrated Management of Solid Wastes until 2025 and Vision Towards 2050. It stresses that organic waste needs to be managed in a cycle, involving the separation of the waste, composting, and utilization of the compost in the arable land of the city.
However, the question is how to translate the national strategy into the local context when a number of composting projects initiated over the past decades have failed in most developing countries [12
]. As is the case in many other environmental situations, utilizing MSW through composting requires a holistic approach involving a range of different stakeholders. This suggests that any decision meant to improve the effectiveness of SWM must seriously consider the perceptions, interests, and roles of all the parties involved [14
]. In other words, the success in solid waste management depends on the extent to which stakeholders are integrated into the management process, thus harnessing their respective resources to build collective strength with a clear division of roles and responsibilities [15
]. So far, with a top-down approach, the municipal authorities of most developing countries retain a key role in the largest part of the solid waste management process [16
]. The lack of the involvement of private enterprises, end-users of recycled products, local communities, and other relevant stakeholders in the waste management process is the main reason for the crisis regarding solid waste management [4
]. The literature reveals that the problem of implementing sustainable municipal solid waste management lies in its practical application [17
]. The practical issues of ability, agreement, coordination, collaboration, and obligations were discussed in the literature [5
]. These problems have been associated with ineffective government policy, poor administration, failures to involve the private sector and local communities, and lack of effective communication [16
]. As a result, low levels of awareness, problems with coordination and bureaucracy, the delicacy of common interests, institutional fragmentation, failure to clarify goals, and an unwillingness to make significant changes to current behavior have existed among stakeholders [13
Where the formal problem-solving structures of government are ill-fitted to solve complex problems [23
], it may be necessary to use governance networks to integrate the required distributed capacities into a problem-solving framework that is more reflexive and thus more conducive to the achievement of development goals [24
]. The adoption of multilevel governance framework has proven to be useful to that end [25
]. The main value of multilevel governance framework is that it allows for an understanding of complexity at and between levels. The vertical dimension refers to the linkages between higher and lower levels of government, while horizontal dimension focuses on the cooperation arrangement between state, market, and civil society actors. These two dimensions often coexist and link to each other [25
]. The use of the governance network approach has been extensively employed to develop conceptual frameworks for addressing the field of environmental management. For example, Francesch-Huidobro [26
], based on a multilevel governance perspective, set out a conceptual framework to examine the governing mechanisms through climate change mitigation and energy decisions that are made in Shanghai, China. Likewise, some have applied a social network approach to analyze natural resources governance [27
], as well as MSW management [14
]. Indeed, the development of governance networks can significantly address the common dilemmas in MSW management. For example, Taiwan has been seen as having a successful practice for targeting urban solid waste, thanks to the engagement of various stakeholders in the MSW management [29
According to Ravetz [30
], for cities to be sustainable, there is a need to move towards a situation where the through-put of resources is reduced (i.e., where it contains its own eco-cycle. This is also the basic philosophy of the circular economy, which has received increasing attention worldwide as a way to increase the efficiency of resource-use-based adoption of closing-the-loop production patterns within an economic system [31
]. Returning organic matter from urban waste back to agriculture soil is one part of this process (Figure 1
). The challenge of linking urban waste to agriculture is that waste must be separated at the source. Waste separation provides a steady supply of organic waste for composting plants. For municipal solid waste, which is high in volume, diverse in nature, and complicated in composition, the most economical and sustainable measure for waste separation is one that relies on residents who directly generate it. Once the separated waste has been composted, the end-product—compost—is believed to provide a productive resource to agriculture. While most composting projects are successful in producing compost, the sustainability of a commercial composting plant will depend on the sale of compost products. The use of compost in agriculture, therefore, ultimately depends on the acceptance of the end-users (i.e., farmers (Figure 1
)). Linking urban waste to urban agriculture, then, presents a systemic problem, which involves a wide range of stakeholders: local residents, waste collectors, waste management officials, composting plants, agriculture development agencies, compost users (farmers), and so forth.
Based on integrated sustainable waste management [15
], this study considers utilizing urban waste in agriculture in a system that consists of the three main components, including (i) system elements—stages in the organic waste management process: waste separation and collection; composting and compost use in agriculture; (ii) aspects—technical, economic, social, institutional, and legal; and (iii) stakeholders—participants in MSW management process. These stakeholders, in many ways, influence various system elements (waste generation and separation, composting, use of compost) through environmental, financial, institutional, legal, and social aspects. Bringing different stakeholders together in the decision-making process is vital. However, very little attention has been given to the stakeholders’ characteristics, their relationships, and how they influence one another. Only by understanding the nature of their interest and inter-relationships can these stakeholders be effectively involved in the system.
To assess the participation of stakeholders in the management of resources and environmental and public administration, stakeholder analysis (SA) is widely used and has proven to be an effective method [27
]. The set of tools included in SA helps to collect qualitative data and generates a general understanding of “a system, and for assessing the impacts of changes to that system, by means of identifying the key stakeholders and assessing their respective interests” [34
] (p. 1). Furthermore, “the purpose of stakeholder analysis is to indicate whose interests should be taken into account when making a decision” [35
] (p. 1). While it was used originally in management science to address the interests of business stakeholders, this method has now become increasingly popular in analyzing the complex situations in environment and resource management, because it helps us to understand the systems and thus propose necessary changes [36
]. In the field of waste management, this method has been employed in various studies to assess the level of knowledge, awareness, interest, and the roles of relevant stakeholders. For example, Snel and Ali [37
] applied SA to examine stakeholder participation in local waste management systems in Pakistan and India. In Vietnam, SA has been employed to identify the constraints to the success of rural sanitation promotion campaigns [38
]. Zurbrugg [39
] utilized SA to indicate that the cooperatives and microenterprises engaged in primary waste collection are considered an important element of the waste management process in Managua.
While SA seems to be a strong qualitative tool that helps to understand the interests and characteristics of stakeholders, it has limitations in assessing the relations and interactions among them. Social network analysis (SNA) offers a solution to this, because it allows for a systematic analysis of relationships, which, according to Wasserman and Faust [40
], are important among these multilevel players. By definition, SNA is “a research technique that focuses on identifying and comparing the relationships within and between individuals, groups, and systems in order to model the real world interactions at the heart of organizational knowledge and learning processes” [41
] (p. 25). SNA has been developed, on the basis of a set of well-proven methods and theories, to contribute to the formulation of quantitative measures of many qualitative concepts that have long been used in the study of society, such as fragmentation, reciprocity, interaction, hierarchy, and cooperation [40
]. This method has recently been extensively applied in studies about natural resource management and public governance issues [43
]. For instance, Stein et al. [46
] used SNA to map out the social complexity that underpins water resource governance in the Mkindo catchment, Tanzania. Cohen et al. [47
] examined a governance network involved in adaptive co-management of coastal ecosystems in the Solomon Islands to indicate that that geographic, logistical, and institutional barriers to cross-scale coordination and learning might hamper coordination and learning among management actors. Hauck et al. [48
] applied social network analysis to understand the stakeholders’ engagement in agriculture biodiversity governance at the local and regional level.
In the last few years, an important methodological trend has developed rapidly to integrate qualitative and quantitative research methods, that is, to employ a “mixed methods” approach [49
]. In line with this trend, several studies have combined SA and SNA to investigate not only stakeholders’ characteristics but also their interactions that help to enhance the co-management processes in environmental and resources management [44
]. For instance, Lienert et al. [27
] demonstrated the added value of combining SA and SNA in examining infrastructure planning in the Swiss water sector. In the field of waste management, this methodological approach has recently been applied by various researchers. For example, Caniato et al. [14
] indicated that the integration of SA and SNA allows for better understanding of actors’ roles and actions, analyzing driving forces and existing coordination among stakeholders in the On-Nuch infectious waste incinerator in Bangkok, Thailand. Xu et al. [33
] used this approach to investigate how the mechanism of food waste management functioned in Beijing, China.
In Vietnam, the specific features of each of relevant stakeholder, as well as their interdependence in their respective local settings, have been under-researched. This study remedies this by employing the multilevel governance framework to explain the governing mechanism through which different types of stakeholders interact with one another and strengthen their roles. More specifically, this study investigates the perspectives of stakeholders in utilizing municipal organic waste in urban agriculture by (i) examining what roles stakeholders could play in relation to the system; (ii) investigating how their knowledge, attitude, interest, power, and alliances can influence the system; and (iii) understanding how stakeholders representing different levels and sectors are integrated into the co-management processes of utilizing urban organic waste in agriculture. A combination of stakeholder analysis and social network analysis was employed to assess these aspects. This methodological approach allows for the analysis of both the characteristics of the stakeholders and their interrelations in the system. Based on the results of the baseline study on the features and relations between different parties, the study creates the potential for strengthening the critical ties among the different parties in the system. Opportunities for and obstacles against turning organic waste from a burden in the management of an urban environment into a resource for agricultural production vary from one country or region to another. One system may function well in this case and yet still fail in another. This study is conducted to present solutions for one particular locality in a specific set of situations. However, it is the authors’ hope that the general approach and methodology of this study can be replicated in similar cities of other developing countries.
Utilizing MSW in agriculture is characterized by complex interactions between different levels and sectors. This study adopted the approach of multilevel governance to investigate the specific features of each of these stakeholders, as well as their interdependence in the respective local settings. A combination of stakeholder analysis and social network analysis was deemed appropriate to evaluate an already established system of utilizing urban waste in agriculture in Hanoi, Vietnam.
According to the results of SA, stakeholders express a significant interest in recycling MSW through composting. However, many of them do not have sufficient power to make any changes to the current system. This imbalance of the power and interest among stakeholders resulted from the fact that only the local authorities, HPC, together with two specialized agencies affiliated with it (DONRE and DOC) are tasked with the responsibility of managing MSW in Hanoi, without close coordination with other stakeholders. Moreover, although the local governmental stakeholders (DOC and DONRE) are certainly the key players in the system due to high interest, power, and degree of centrality values, they have only been involved in the collecting, transporting, and disposing of waste without making substantial efforts in separating and composting it. Meanwhile, the other players, such as agencies in agricultural production management (CD, DARD, AES), have not paid significant attention to introducing and promoting compost in agriculture. Moreover, the community level (PCWs, CSOs, local residents, and farmers) and the intermediary parties (the academia and media) were only judged as potential, instead of actual stakeholders. Therefore, incentive policies need to be designed to allow the potential key players to get involved in the system.
SNA helped to assess the stakeholders’ connections. The analyses of degree and betweenness centrality values showed that there is a lack of connection among stakeholders. It is critical to see that the cooperation among the stakeholders is mainly realized in a hierarchical manner without adequate horizontal interactions, leading to apparent network fragmentation in the system. This fragmentation can be attributed to the weak legislative framework, lack of trust, financial constraints, and limited participation of private enterprises, which were identified by SA. Therefore, a legal framework with specific regulations and guidelines is required. There also needs to be a mechanism to enable non-state stakeholders (private enterprises, local residents, farmers, CSOs, ACs, etc.) to take responsibility for operating the system and to benefit from their contributions.
Dynamic economic growth in Asia has been accompanied by a worrying rapid increase in the volume and complex changes in the composition of waste. The significant presence of organic waste in the waste stream has represented a constant challenge to all countries in the region. Subsequent research, therefore, should strive to determine the tendency of generated organic waste in terms of volume, density, moisture, and calorific value. In addition, it is also necessary to identify the similarities and differences among regional countries with regard to the technical, financial, institutional, legal, social, and economic aspects in order to propose a guiding framework for the formulation of sustainable strategic plans for organic waste management in the region.
This study focuses on composting and assumes it to be a suitable method of organic waste recycling in a largely agriculture-based economy, such as Vietnam. However, as organic waste has become a global issue, not only for developing, but also for developed countries, due to increased food waste [4
]; relying only on recycling does not guarantee a sustainable solution to the problem. Composting is essentially a principle in the performance of circular economy. The circular economy, however, is more about preventing than recycling waste. It also attempts to switch from the present model of production and consumption (take, make, waste) that is discoloring soil and generating waste at an alarming rate to one that maximizes resource efficiency and minimizes the amount of natural resources required in production and waste discharged into the environment [31
]. For this shift to take place, we will need the consensus and cooperation of all parties. Therefore, it is necessary in the current situation to examine factors influencing the awareness and cooperation of stakeholders in moving away from the old economic model to a circular one. Subsequent research can adopt a multilevel framework to assess the roles, responsibilities, and the interdependencies of stakeholders in the realization of a circular economy at the microlevel (producers’ and consumers’ responsibilities in food production, sale, and consumption), at the meso-level (reuse and recycle organic resources within eco-industrial parks), or at the macrolevel (circular economy development in cities, provinces, or regions (e.g., eco-city, collaborative consumption models, or zero-waste programs)).
This study demonstrates that SA and SNA are complementary and together can provide an effective method to assess and understand the overall system. This approach could be helpful for assessment at all stages of a project cycle. However, SA and SNA have their own shortcomings in the sense that they can only create maps of information on an ad hoc basis at one certain point in time. Therefore, the process of development and the changes in roles, awareness, and attitudes of stakeholders over time have not been captured [39
]. Further research can redress this shortcoming by amassing information at two different evaluation points: past and present. However, this also further complicates the interview process, timing, and budgeting issues. In fact, being able to approach specialized agencies of the city is already a challenge per se.