Environmental Kuznets curve (EKC) hypothesis: A bibliometric review of the last three decades

The environmental Kuznets curve (EKC) is a widely tested hypothesis in the environmental economics literature. It explains the dynamics between economic growth and environmental degradation. This study conducts a bibliometric analysis for the past three decades (1994–2021) that contributes to the intellectual structure and knowledge progress of the EKC hypothesis using descriptive analysis and networking analysis. The descriptive analysis comprises publication trends, language, publishers, Web of Science category and research areas, and citation analysis. Meanwhile, networking analysis includes keyword co-occurrence analysis, co-authorship analysis and co-citation analysis. The findings of the descriptive analysis reveal that the number of publications in the EKC hypothesis has gradually increased over the years. The most productive publishers are Elsevier and Springer Nature. Researchers from China and Turkey tend to be the most prolific authors, with the highest number of citations, co-authorships and co-citations. According to the network analysis, the main keywords appearing in the EKC studies are economic growth, CO₂ emissions, energy consumption, China, renewable energy and financial development, which is also supported by the most frequently used keyword plus and its clusters. Based on our findings, we have proposed several policy recommendations from the keyword analysis that could foster economic development and improve environmental quality simultaneously. From the emerging trends of EKC, new directions for future research are also proposed.