Global performance and development on sustainable city based on natural science and social science research: A bibliometric analysis.

Sustainable city has been a global concern in recent years, involving natural science and social science research. However, few studies have attempted to map the global research of sustainable city. This study aimed to reveal the global performance and development of sustainable city research during 1992 to 2016, using a bibliometric analysis based on Science Citation Index Expanded (SCI-EXPANDED) and Social Sciences Citation Index (SSCI) on Web of Science. Research performance, research emphases and trends were illustrated by bibliometric indicators and newly developed visualization tools, like Science of Science (Sci2), Gephi, and alluvial diagram. Sustainable city research in natural science and social science were well-matched in quantity, and had similar and different characteristics in terms of different investigated aspects. China ranked first in natural science research, while the USA was the leading country in social science research. More categories and clusters were involved in sustainable city field, indicating more interdisciplinary integration was undergoing. Energy and fuels in natural science field, and interdisciplinary applications mathematics in social science field started to attract more attention. Statistical analysis of words in title, author keywords, and KeyWords Plus has been investigated to monitor the development of sustainable city research. Finally, three critical issues in sustainable city research based on the clues by the analysis of these keywords were reviewed and discussed.