Green supply chain management practices' effect on the sustainability performance: A case study in the Turkish shipyards

Tantan, Mehmet
Süreli Yayın başlığı
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Graduate School
The study in this Ph.D.thesis concerns the green supply chain management practices, their impacts on sustainability performance; environmental, economic, and social performance by conducting a case study in Turkish shipyards. The more detailed objectives are; to select the optimum green supply chain management practices to fit in shipyards, to examine the impact of green supply chain management practices on the sustainability performance of shipyards, the moderator effect of environmental uncertainty on the relationship between green supply chain and sustainability performance, the mediator effect of environmental uncertainty between green supply chain and sustainability performance and the determine the penetration level of green supply chain management practices on the Turkish shipyards. Sustainability is an essential issue in the twenty-first century regarding the environmental consequences of climate change. Green supply chain management progressively emerged to improve environmental performance. Although environmental, sustainability, green supply chain areas are popular study subjects, shipbuilding and shipyards were not examined in detail. A systematic literature review between 1980 and 2020 unveiled rare studies concerning green supply chain management sustainability in shipyards and shipbuilding. The filtered articles were categorized into shipbreaking, shipbuilding, maritime, and various. China and South Korea emerged as leading areas for research in Asia since shipbuilding is seen as a driving factor for development and growth in those economies. In Europe, Spain, Turkey, and Holland emerged as research areas. The main focus areas in the shipbuilding category are shipyard layout design according to the greenfield project, sustainable growth directions for small and medium shipyards, the ways to improve the sustainability in the shipbuilding supply chain, green shipping, and green manufacturing in the shipyard. Therefore, this thesis is the first study of the impact of green supply chain management practices on shipyards' sustainability performance. Green supply chain management is challenging to describe because of the broad concept. Many academicians reached different definitions. An increasing number of studies about the relationship between Green supply chain management practices and companies' performance have existed in the literature since 2014. These studies have categorized sustainability performance as environmental, economic, social, and operational performance. In contrast, various GSCM practices such as green purchasing, green packaging, recycling, eco-design, internal environmental management, reverse logistic, green production, green marketing, environmental collaboration with suppliers and customers have been questioned in these studies. The researchers found both negative and positive, primarily partial, relationships between GSCM practices and the company's performances. The authors reviewed all practices in the literature and considered practices directly related to the shipbuilding industry. For example, environmental training is a part of internal environmental management, and therefore these two applications converged as environmental management. Practices like green packaging and green transportation have little effect on the shipbuilding process and are omitted from the study. Consequently, green design, green purchasing, green production, green marketing, environmental management, recycling are selected as exogenous latent variables for the research model. Economic, environmental, and social performances are entered as endogenous latent variables for the research model. The environmental uncertainty (ENVR-UNCER) is embedded in the research model as either a moderator or a mediator variable. Environmental uncertainty is measured as demand, supply, and technology uncertainty. The shipbuilding industry creates substantial economic value but causes many environmental and social issues. Sustainability, environmentally driven regulations, and voluntary standards adopted in the sector have impacted shipbuilding and shipyards in the case of new design and construction standards. Major international shipbuilding companies publish yearly sustainability reports indicating sustainable development goal achievements. The survey is based on academic studies in Turkish chemical, electronical, automotive, food packaging industries. The survey consists of three main parts. The first part contains an introduction letter with a brief explanation of the study. The second part is the demographic questions like general information about the company and the quality and environmental certificates. In the third part, the survey questions are grouped to green supply chain management practices, environmental uncertainty, and sustainable performance. The understanding of scales by the applicant and time constraints were two main obstacles to accomplishing the survey completion rate. Therefore, the author summarized the scales into expressed sentences and limited them to 33 questions. The survey filling time is a critical factor. It is arranged for around 15 minutes on average because most executives claim the intense work environment and use it as an excuse not to fill the survey. The survey used a 5-Likert type, the most preferred scale in the literature. A pilot test with shipyard executives and shipyards' owners enabled improved scales and corrected the expression failures. The final survey is applied among the GISBIR members by email. The responses are stored in the VETI system and downloaded for analysis. A favorable finding of the survey is the certification outcome. All shipyards have a minimum of two certificates (ISO 9001 and ISO 14001, 30% of the answers). Only two small shipyards have a single certification, ISO 9001. A high portion of the shipyards has all three certificates (ISO 9001, ISO 14001, and ISO 45001). Those findings proved that Turkish shipyards embraced environmental issues and took necessary internal and external actions to improve their business competence. Since the Turkish shipyard quantities are limited to 68, partial least square structural equation modeling (PLS-SEM) is selected to eliminate the sample size constraint. The research model is defined in the SmartPLS software. To decrease the number of relationships and make the model more parsimonious and simple, authors preferred to form a hierarchical-order model, ease the calculation and simplify the research model. The disjoint two-stage approach is implemented. Green design, green purchasing, green production, green marketing, environmental management, and recycling formed the higher-order construct named GSCM. Demand uncertainty, technology uncertainty, and supply uncertainty formed the higher-order construct named ENVR-UNCER. Demand uncertainty indicator is omitted to obtain HOC reliability convergent and discriminant validity during the assessment of the measurement model. All other indicators satisfied the criteria and were kept in the model. After the structural model assessment, GSCM practices have been found to impact positively on economic and social performance, but not environmental performance. The environmental uncertainty did not have a moderating effect but mediates only the relationship between GSCM practices and social performance.
Thesis(Ph.D.) -- Istanbul Technical University, Graduate School, 2023
Anahtar kelimeler
shipbuilding sector, gemi inşaat sektörü, shipbuilding industry, gemi inşaatı endüstrisi, corporate sustainability, kurumsal sürdürülebilirlik, green supply chain, yeşil tedarik zinciri