# Advancements in Phytoremediation Research in South Africa (1997-2022)
## 3 Results and Discussion
### Relevant Journal Analysis  
The retrieved data from WoS indicate that 39 documents were published in 30 sources--Table 1. In bibliometric analysis, journals and subject categories are tools that elucidate divisions of research scope in a particular topic [45]. In the current study, the publications on phytoremediation-related research in South Africa from inception to 2022 were \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Authors** & **h\_index** & **g\_index** & **m\_index** & **TC** & **NP** & **PY\_start** & **AF** \\ \hline KIRKHAM MB & 4 & 5 & 0.211 & 183 & 5 & 2005 & 2.33 \\ LIPHAD2I MS & 4 & 5 & 0.211 & 183 & 5 & 2005 & 2.33 \\ ATAGANA HI & 2 & 4 & 0.154 & 53 & 4 & 2011 & 2.50 \\ BRINK IC & 2 & 2 & 0.4 & 6 & 3 & 2019 & 1.00 \\ BROOKS RR & 2 & 2 & 0.074 & 184 & 2 & 1997 & 0.45 \\ DE WAAL J & 2 & 2 & 0.4 & 6 & 3 & 2019 & 1.00 \\ HOWES AW & 2 & 2 & 0.074 & 184 & 2 & 1997 & 0.45 \\ JACKLIN DM & 2 & 2 & 0.4 & 6 & 3 & 2019 & 1.00 \\ ROBINSON BH & 2 & 2 & 0.074 & 184 & 2 & 1997 & 0.45 \\ ABDEL-GAYED MES & 1 & 1 & 0.2 & 15 & 1 & 2019 & 0.14 \\ ABED SN & 1 & 1 & 0.2 & 9 & 1 & 2019 & 0.33 \\ ADENUGA DO & 1 & 1 & 0.333 & 13 & 1 & 2021 & 0.33 \\ AHMAD F & 1 & 1 & 0.091 & 137 & 1 & 2013 & 0.33 \\ ALMUKTRA SA & 1 & 1 & 0.2 & 9 & 1 & 2019 & 0.33 \\ ANDERSON CWN & 1 & 1 & 0.1 & 44 & 1 & 2014 & 0.08 \\ ANYASIOR & 1 & 3 & 0.083 & 16 & 3 & 2012 & 1.50 \\ ASEMOLOYE MD & 1 & 1 & 0.5 & 75 & 1 & 2022 & 0.33 \\ BABALOLA OO & 1 & 1 & 0.091 & 137 & 1 & 2013 & 0.33 \\ BADEJO AA & 1 & 2 & 0.111 & 10 & 2 & 2015 & 0.45 \\ BANDA MF & 1 & 1 & 0.5 & 4 & 1 & 2022 & 0.25 \\ \hline \hline \end{tabular}  
* TC: total citation; NP: number of publications; PY: publication year; AF: article fractionalized.  
\end{table} 
Table 2: Top 20 authors in phytoremediation-related research in South Africa. Figure 4: Collaboration of authors in phytoremediation-related research in South Africa. divided into 20 WoS subject categories. The top categories are Environmental Sciences (\(n=17\), 43.59%), Water Resources (\(n=8\), 20.513%), Plant Sciences (\(n=7\), 17.949%), Agronomy (\(n=3\), 7.692%), and Engineering Chemical (\(n=3\), 7.692%). The most relevant journals on the subject are the _International Journal of Phytoremediation_ (\(n=4\), IF = 4.003), the _South African Journal of Botany_ (\(n=4\), IF = 3.111), _Water SA_ (\(n=4\), IF = 1.586), _Applied Ecology and Environmental Research_ (\(n=1\), IF = 0.816), and _Chemosphere_ (\(n=1\), IF = 8.943)--Table 3. Although the _International Journal of Phytoremediation_ has the highest number of publications (\(n=4\)), the _Journal of Geochemical Exploration_ has the highest total citation (161 citations), followed by _Reviews of Environmental Contamination and Toxicology_, vol 223 (137 citations) and the _South African Journal of Botany_ (112 citations). The analysis of the most active journals indicates the studies in this field are environment-centered. In addition, the relationship among journals was mapped in VOSviewer based on the shared references and total citations [33]. A fractional counting method with a minimum of a document in a journal was deployed for the bibliographic coupling of 30 journals involved in the publication of phytoremediation-related research in South Africa from inception to 2022. For each of the 30 article sources, the total strength of the coupling links with other sources was estimated, and the source with the greatest total link strength was selected. One of the article sources is not connected to the network; thus, the remaining 29 connected sources are shown in Figure 5. The mapped network has 137 links and 182.02 total link strength and is divided into five clusters represented with different colors. \"Cluster 1 consists of eight items\", \"Cluster 2 (seven items)\", \"Cluster 3 (seven items)\", \"Cluster 4 (four items)\", and \"Cluster 5 (three items)\". Among the three leading journals in terms of the number of publications and h_index, the _South African Journal of Botany_ has the highest links of 16 and a total link strength of 35.55.