NITROUS OXIDE EMISSION FROM LANDFILLS: A BIBLIOMETRIC ANALYSIS

Abstract

Urban solid wastes need to be properly disposed and one of these means is the landfill, where wastes organic fraction degradation occurs. One of the by-products generated in this environment shows high ammonia nitrogen concentrations in its constitution, which can cause the increase in nitrous oxide (N₂O) production rates. N₂O is one of the main greenhouse gases, with high global warming potential. In view of the scarce information on the N₂O emission in landfills, the objective of this study was to evaluate the research trends on the emissions of this gas, especially in landfills, using the bibliometric analysis as a tool. The publications survey was conducted in the Web of Science database from 1991 to 2021. First, papers on N₂O emission sources were researched and, later, the scientific studies that were only related to landfill emissions were verified. The following parameters were evaluated: scientific journals, authors, countries, number of publications over time, research institutions, keywords occurrence, and Web of Science categories. 3,988 papers on N₂O sources in general and, 146, on landfill emissions were found. In both analyses, there was a predominance of Chinese publications and very few Brazilian publications, since among the studies on the various emission sources, 125 Brazilian papers and no paper in the case of landfills were found.  Regarding the temporal analysis, there was a trend of linear increase in the number of publications for both analyses. With this survey, the need to conduct more research on the N₂O emission in landfills was found, especially in Brazil, in order to obtain an accurate knowledge on how this source can affect the global balance of this gas with high impact in climate changes.