Bibliometric Analysis of Soil Nutrient Research between 1992 and 2020

Soil nutrient balance is related to the interaction mechanism between soil fertilizer, soil water, climate change, and plant capability. This paper provides a perspective from bibliometric analysis based on data from the Web of Science core collection with software tools, including Vosviewer, HistCite Pro, and Citespace, in order to reveal the evolution of research trends in soil nutrients. The results show that publication outputs have increased exponentially from 1992 to 2020. The synthetic parameter of the sum of normalized data (SND), calculated from the default indicators of the bibliometric software tools, was used to rank the overall contribution of journal/authors/institutions/countries. The results demonstrate that Agriculture Ecosystems & Environment, Soil Biology & Biochemistry and Science of the Total Environment are the leading journals in the soil nutrient field. The Chinese Academy of Sciences had the highest total citations and collaborated most closely with other organizations, followed by United States Department of Agriculture (USDA) Agricultural Research Service (ARS) and Agr& Agri Food Canada. In addition, USA, China, and UK are the top three research centers for this topic. Moreover, Ken E Giller, Qirong Shen, and Rattan Lal were the top three authors, while Andrew Sharpley ranked the first depending on citations per publication. In terms of co-occurrence of keyword analysis, the results indicate that nitrogen fertilizer, green manure, and soil population have gained close attention from scholars, while soil amendment of biochar have evolved as a hot topic in recent years. Perspectives on future studies are also given.