3.3 Journal co-citation analysis
A total of 3,307 publications on hydrological connectivity were published in 783 journals from 1998 to 2018. Table 2 shows the top 10 journals and co-cited journals in hydrological connectivity. Hydrological Processes is the most productive journal, it has published 193 papers (accounting 5.8%), the second is Journal of Hydrology (149 publications, 4.5%), followed by Water Resources Research (139 publications, 4.2%). Among the top 10 productive journals, Science of the Total Environment has the highest impact factor (IF), 5.589. Moreover, the journal with the most citation count was Hydrological Processes, 1,585 totally, followed by Journal of Hydrology (1,561 records) and Water Resources Research (1,517 records). To obtain information about the co-cited relations between journals, the network is given in Fig. 3. As can be seen from Fig. 3, the co-cited relationship between each journal is very close, especially the journal represented by the node with the purple ring. Moreover, seven of the top ten co-cited journals had high centrality. Particularly, though some journals with a small number of publications, they still have a high centrality, which indicates that the articles published in these journals have a strong research value.
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Please Place Figure 3 and Table 2 here
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