A Systems Approach to Ecological Economic Models Developed Progressively in Three Interwoven Articles

My dissertation develops and analyzes ecological economic models to study the complex dynamics of an ecological economic system (EES) and investigate various conditions and measures which can sustain a developing economy over the long term in view of resilience and sustainability. Because of the intrinsic complexity of the system, I take a systems approach, using economics as the foundation for the basic structure of an ecological economic model, and system dynamics as the method to build and analyze such a complex ecological economic model. Throughout my dissertation, the model developed by Brander and Taylor (1998) is adopted as a baseline model (henceforth the BT model). The BT model explains population-resource dynamics and is characterized as a general equilibrium version of the Gordon-Schaefer Model, using a variation of the Lotka-Volterra predator-prey model. The findings are presented as three articles. The first article provides a comprehensive analysis of the BT model and its descendants, to elicit directions for further research, including population growth logic, substitutability, innovation, capital accumulation, property rights and institutional designs, and modeling approach. The second article extends the BT model to study the resilience of an EES reflecting three key issues in modeling such systems: 1) appropriate system boundary, 2) non-convexity of ecosystems, and 3) adaptation. The article discusses two types of thresholds: the ecological threshold, a threshold for an ecological system independent of economic systems, and the ecological economic threshold, a threshold for an EES. The latter is often different from the former and is highly dynamic and context dependent. The third article is another extension of the BT model to study the sustainability of an EES by implementing the suggestions made by the first article except for property rights and institutional designs. The main focus is on the impact of endogenous innovation regarding input substitutability on the system sustainability. The main finding is that improvement in the input substitutability, ceteris paribus, may not contribute to sustainable development despite its contribution to expanding the economy. However, it could be possible for susbstitutability improvements to contribute to sustainable development when combined with other specific types of technological progress

System Dynamics Implementation of a Model of Population and Resource Dynamics with Adaptation

We build and analyze a dynamic ecological economic model that incorporates endogenous innovation on input substitutability. The use of the system dynamics method allows us to depart from conventional equilibrium thinking and conduct an out-of-equilibrium (adaptation) analysis. Simulation results show that while improvement in input substitutability will expand an economy, this change alone may not improve sustainability measured by indicators such as utility-per-capita and natural resource stock. It could, however, be possible that in combination with other technological progress, improvement in input substitutability will contribute to sustainable development. Sensitivity analysis also indicates a possible complication with the use of exogenous consumer preference, which is often assumed in standard economics

Young consumers’ perceptions of and preferences for alternative meats: an empirical study in Japan and China

IntroductionAlternative meats have the potential to shape a sustainable food system. This study examined young consumers’ perceptions of and preferences for plant-based and cultured meats. Since comparative studies on consumer preferences for alternative meats in different key Asian markets remain insufficient, this study was conducted in Japan and China, both of whom have promising alternative meat markets in Asia.MethodsWe conducted a discrete choice experiment and co-occurrence networks among 2006 (n = 887 in Japan and n = 1,119 in China) young consumers. This study adopted a treatment-control design where respondents in the treatment groups received health information on the use of antibiotics in meat production.ResultsRespondents in both countries perceived meat alternatives to be substitutes to conventional meat and associated them with plant-based proteins, processed products, and health benefits. In general, Japanese and Chinese respondents differed in their preferences for burger patties but had similar preferences for other attributes. Respondents in both countries were willing to pay a premium for “antibiotic-free,” “traceable,” and low carbon footprint labeling. This study reveals the heterogeneity of consumer preferences and the complexity of the impact of information interventions on consumer preferences.DiscussionPlant-based meat is already available on the market in both countries, whereas cultured meat is still in the research and development stage. Hence, young consumers were more familiar with plant-based meat than cultured meat. It is worth noting that young Japanese consumers preferred cultured meat to conventional meat. This is attributed to the concerns about food security and food animal welfare. Furthermore, this study found that information intervention can induce and direct respondents’ attention to an aspect of alternative meats that is negatively perceived. Based on the findings, this study has three implications for promoting alternative meat products: marketing messaging, food labeling, and product development

The potential impact of the new ‘Right to Repair’ rules on electrical and electronic equipment waste : a case study of the UK

Every year an estimated two million tonnes of waste electrical and electronic equipment (WEEE) are discarded by householders and companies in the United Kingdom (UK). While the UK has left the European Union (EU), its waste-related policies still mirror those of the EU, including the WEEE-related policies. Motivated by the recent introduction the so-called ‘Right to Repair’ policy for electrical and electronic equipment (EEE) across the EU and UK, this paper aims to demonstrate that, depending on the commitment and behavioural changes by the consumers and the government, the future of the WEEE management of the UK will vary. To this end, focusing on landfilled WEEE reduction we develop a generic system dynamics model and apply it to eleven WEEE categories. They depict the flow of EEE and WEEE representing the interaction among the stakeholders (e.g., consumers and producers of EEE) and relevant government regulations of the UK. Our four scenario analyses find that longer use of EEE and better WEEE collection seem to be effective in reducing landfilled WEEE, while more reuse and more recycling and recovery have negligible impacts, despite excluding the additional generation of landfilled WEEE as a result of recycling and recovery. Comparing with the business-as-usual scenario, one year longer EEE use and 10% more of WEEE collection could at maximum reduce landfilled WEEE by 14.05% of monitoring and control instruments and 93.93% of display equipment respectively. Backcasting scenario analyses reveal that significant efforts are required to reduce the targeted amounts

The importance of relational values in gaining people’s support and promoting their involvement in social-ecological system management: A comparative analysis

People’s support and involvement are critical to the sustainable use and conservation of social-ecological systems (SESs). Integrating people’s values into management decisions is pivotal. Without proper integration, the resulting SES may not align with their desires and may not be supported by people. Furthermore, values can be a deep leverage point within a system that is difficult to change, as people may be more willing to be involved in activities that support what they value. Recent studies have illustrated the importance of relational values as the third value class (in addition to instrumental and intrinsic). Relational values are preferences, principles, and virtues associated with human-nature relationships. Although studies on relational values are available, empirical studies, particularly studies about the usefulness of relational values in promoting pro-SES behavior, are rare. Consequently, our study administered questionnaires to residents in three SESs in Japan (N = 864, 1136, and 1000, respectively) to understand how relational values impact people’s support and involvement in SES management as measured by pro-SES behavior scales. In addition, due to the lack of pro-SES behavior measurements, we developed measurement items and a development guideline. Our findings support previous theoretical discussions positing that relational values are critical as a single value class or as part of the plural values and need to be integrated into SES management decisions to gain people’s support. Furthermore, our study demonstrated that cultivating relational values could promote pro-SES behavior to realize a desirable state of SES. Although from the viewpoint of residents, relational values overlapped with instrumental and intrinsic values; however, as per theoretical discussions, the results indicated that relational values were important in their own right as they were well associated with pro-SES behavior scales. The findings were similar across the three SESs, with different social-ecological characteristics. In summary, managers must integrate relational values into management decisions to gain people’s support and should cultivate relational values to promote pro-SES behavior, in order to realize a desirable state of SES

Development of D-to-D-to-P telemedicine at a remote island hospital using smart glasses

Background: Medical resources on remote islands are limited, which makes it difficult for patients to receive specialized medical care.Purpose: This study aimed to develop and evaluate a method to perform doctor-to-doctor-to-patient (D-to-D-to-P) telemedicine.Methods: The-D-to-D-to-P telemedicine was implemented to provide specialized medical support from a neurologist at Nagasaki University Hospital to a rural physician wearing camera-equipped smart glasses at Goto Chuoh Hospital on a remote island, which was called a virtual neurological outpatient (VNO). For the first six months, the rural physician independently saw patients with Parkinson’s disease (PD), and then for the next six months, VNO was implemented. Comparisons were made before and after the implementation of the VNO. Next, by adding a 4 K overhead camera, in-person examinations of a single outpatient were compared between the rural physician with VNO and another neurologist unrelated to the VNO.Results: The clinical efficacy of VNO was not superior to no VNO, but had a learning effect on rural physicians and was satisfactory for patients. By adding a 4 K overhead camera to the VNO, the accuracy of the in-person examination by the rural physician was shown to be equivalent to that of an in-person neurologist.Conclusion: VNO using smart glasses could be applied for D-to-D-to-P telemedicine in neurology. However, to promote telemedicine on remote islands, it will be necessary to improve the system to make it more accessible to rural physicians

Fully Dynamic Input-Output/System Dynamics Modeling for Ecological-Economic System Analysis

The complexity of ecological-economic systems significantly reduces our ability to investigate their behavior and propose policies aimed at various environmental and/or economic objectives. Following recent suggestions for integrating nonlinear dynamic modeling with input-output (IO) modeling, we develop a fully dynamic ecological-economic model by integrating IO with system dynamics (SD) for better capturing critical attributes of ecological-economic systems. We also develop and evaluate various scenarios using policy impact and policy sensitivity analyses. The model and analysis are applied to the degradation of fish nursery habitats by industrial harbors in the Seine estuary (Haute-Normandie region, France). The modeling technique, dynamization, and scenarios allow us to show trade-offs between economic and ecological outcomes and evaluate the impacts of restoration scenarios and water quality improvement on the fish population

System Dynamics Implementation of an Extended Brander and Taylor-like Easter Island Model

We provide a system dynamics implementation of a dynamic ecological economics model. Dynamic economic models are often constrained to use functions, such as the Cobb-Douglas function, chosen “conveniently” to allow for analytic solutions. The C-D function, however, suffers from its fixed elasticity that does not allow for the substitutability between man-made capital and natural capital to change, which is vital for economic sustainability. Using system dynamics removes this constraint and enables more realistic ecological economics models containing functions not amenable to analytic solution. The base model is the natural resource and population growth model developed by Brander and Taylor (1998) that employs a Lotka-Volterra type structure and strictly follows economic theory in all aspects of its formulation. To make the model more realistic and to enable the consideration of critical environmental issues, we discuss and employ model extensions inspired by modern economics theory. One extension is to use a CES production function with a dynamic substitutability parameter that enables the study of long-term sustainability of the modeled economy. The model does not have an analytic solution, necessitating a simulation approach. Importantly, under certain conditions the system dynamics implementation robustly returns to equilibrium after disturbances

Using System Dynamics to Contribute to Ecological Economics

This paper demonstrates the usefulness of the system dynamics approach to the development of ecological economics, the study of the interactions between economic systems and ecological systems. We build and analyze an ecological economic model: an extension of a population–resource dynamics model developed by Brander and Taylor and published in American Economic Review in 1998. The focus of the present paper is on the model building and analysis to contribute to theory building rather than eliciting policy implications from the model. Hence, this is an example of model-based theory building using system dynamics. Our analysis sheds light on several problems with this type of ecological economics model that can be attributed to three commonly taken approaches to model building and analysis by traditional economics: simplification through the use of exogenous variables, equilibrium thinking, and a focus on the so-called balanced growth path. To solve these problems ecological economic models should adopt approaches that are not prevalent in traditional economics such as taking an endogenous point of view and allowing for out-of-equilibrium (adaptation) which are key principles of the system dynamics method

How much innovation is needed to protect the ocean from plastic contamination?

International audiencePlastics are non-biodegradable, and increasing accumulation of plastic debris in the ocean is a major cause for concern. The World Economic Forum, Ellen MacArthur Foundation, and McKinsey & Company claimed in 2016 that technological innovations can solve the plastic problem. Such a claim raises an as yet unanswered question: how much technological innovation is needed and is it economically feasible? We offer answers to this question via a system dynamics model that we developed to simulate different scenarios aimed at controlling plastic debris entering the global ocean. Our results show that ocean cleanup technologies could achieve a 25% reduction in the level of plastic debris in the ocean below 2010 levels in 2030. However, this would require removing 15% of the stock of plastic debris from the ocean every year over the period 2020–2030, which equates to 135 million tons of plastic in total (metric tons). The implementation cost of such an ocean cleanup effort would amount to €492 billion-€708 billion, which represents 0.7%–1.0% of the world GDP in 2017 – this calculation is based on unit costs in €/kg estimated in The Ocean Cleanup project feasibility study. The Ocean Cleanup project alone is designed to collect 70,320 tons of plastic debris over a 10 year period. Removing 135 million tons of plastic debris would require investing in 1924 similar cleanup projects. These results help to assess the economic feasibility of removing such large volume of plastics. Moreover, our results provide quantitative confirmation that technological solutions alone are not sufficient to solve plastic pollution issues. A portfolio of diverse solutions – not only technological ones – is likely to have greater technical, political and economic feasibility. Our model shows that such a combined portfolio implemented over the period 2020–2030 could reduce the ocean plastic stock to 2013 levels (94 million tons) by 2030