20. Statistical Analysis of Water and Sediment Research in Heilongjiang River Basin

To understand the development history and variation of research focused on water and sediment in the Heilongjiang River Basin, statistical analysis was conducted based on the databases in Web of Science. Aspects including the number of publications, countries, institutes, subject categories, words in the title, and article adoptions were analyzed, which could provide a basis for future research directions. The results show that the development history can be divided into three stages: the early stage from 1943 to 2001, the rapid development stage from 2002 to 2013, and the current stage of 2014 to present, where the number of publications per year is relatively large. China and Russia pay the highest attention to this field because Heilongjiang is a boundary between the two countries. Correspondingly, most number of publications are from the Russian Academies of Science followed by the Chinese Academies of Science, which are followed by the universities and institutes in the northeast of China which account for the third largest number of publications to the tenth largest number. Furthermore, it was found that international cooperation is scarcer than domestic cooperation. As for the subjects, the number of publications under the subject of ecological environment ranks first; attentions paid to water and sediment movement and riverbed evolution are low. The results of title word frequency for all publications show that the word “water” ranks first which is much higher than “sediment;” “soil,” which is related to agriculture and forestry, ranks second. Currently, research on characteristic analysis is at the forefront, model development is next, and the theoretical studies are relatively scarce. Our research is of immense significance since the results of our study can identify research hotspots and trend changes, and hence, can provide references for research in the same field.