Mercury (Hg) researches in Brazilian biomes: A scientometric analysis between the years 1991 and 2018

Mercury is a metal present in natural sources and its concentration have been allocated by human activities, posing impacts in environmental matrices and organisms. In this study, we highlight the panorama of Hg researches in Brazilian biomes in the scientific literature published between 1991 and 2018. Although the appreciated attention to the mercury researches in Amazon context, there has not been an assessment of Hg research within other Brazilian biomes. With this in mind, we searched for articles in the periodic database the Thomson’s ISI Web of Science database and observed an oscillated trend of the number of publications throughout this period. The low percentage of papers performed in Pantanal (8%), Caatinga (4%), Atlantic Rainforest (4%), Pampa (3%) and Cerrado (0.36%) was contrasted to majority academic works performed in Amazon regions (83%), indicating the asymmetrical geographical distribution in Hg researches. The five top keywords of research topics were mercury, Amazon, Brazil, river, Brazilian and fish. The top authors formed 19 different clusters, with different research directions and strengths. Our data shows that Hg studies have been geographically biased. The lack of Hg studies on other Brazilian biomes may mask the extent and intensity of the impacts related to the Hg mobilization in these areas. Concerning Hg concentration is context-dependent, we emphasize the need for investment in Hg research in different tropical biomes in order to overcome spatial bias of Hg knowledge, particularly with organisms from different environmental matrices. Keywords: Scientometry; Mercury; Brazilian biomes, Web of science (WoS)