Global Trends in Dam Removal and Related Research: A Systematic Review Based on Associated Datasets and Bibliometric Analysis

Dam removal has been increasingly reported globally and is becoming an important approach for river management, restoration and environmental conservation in damming rivers. However, current limited knowledge of global trends in dam removal and related research may be potentially biased in terms of the geographic distribution and organisms studied. Such bias could mislead dam removal planning and management in different areas and ecological conservation for different taxa. In this study, we quantitatively and qualitatively analyzed datasets of dam removal and publications of dam removal research using bibliometric methods. A total of 1449 dam removal documents were published from 1953 to 2016. Trends, current hotspots and future directions of dam removal research were identified. The results from this study reveal that dam removal largely occurred in the North America and Europe, and most of the removed dams were small and old dams. With respect to the topic analysis, more dam removal studies should focus on the responses of a wide range of organisms, not only fish, as well as the interspecies relationships, food webs and ecosystem structures and functions. Based on our findings, we also provide some suggestions for future dam removal planning and analysis.