## 2 Research Scope, Methodology, Bibliometric, and Citation Analysis
### Bibliometric and Citation Analysis  
A bibliometric analysis of 121 references shows critical insights into the existing research landscape for IoT-based composting in modern city ecosystems. It emphasizes the importance of a cohesive and strategic approach. Journal publications dominate 80.99% of the total; 14.05% are conference proceedings, while only 4.96% are book chapters and technical reports (Figure 2). This suggests that despite a solid academic foundation, more applied and practical guidance for scalable solutions is needed (Figures 3 and 4). 16.5% (20 publications) are focused on IoT-based urbanized composting automation, reflecting increased attention to automation and real-time urban composting process monitoring with limited attention to the scalability of the systems (e.g., [20; 21]). With an average of 194.8 citations per publication, IoT-based urbanized composting automation shows high variance, signaling fragmented research in urban-level applications. Intelligent composting process optimization comprises 22.3% (35 publications), with the lowest citation impact of 72.7 of mean citations. Therefore, despite the development of localized intelligent composting process optimization systems, there is a need for more cohesive frameworks optimized for city-wide composting operations (e.g., [22; 23]). Studies like [20; 24] are included in the largest category, sustainability and urban waste management, which accounts for 28.9% of all publications (35 total), with an average of 138.5 citations per article. Despite widespread interest in sustainability, only a few of these studies integrate IoT to achieve sustainability in urban ecosystems, exposing limitations in adopting IoT. As seen in [25; 26], pollution monitoring and environmental impact, which accounts for 19.0% (23 articles), has a strong emphasis on pollution control. It has an average of 163.5 citations but little IoT integration for real-time environmental monitoring. Lastly, with an average of 211.8 citations, cost and life cycle assessment accounts for 13.3% of all papers (16 publications), including works such as [27; 28]. Although economic evaluations are of great importance, no reliable cost models in this area are necessary for expanding IoT composting systems in urbanenvironments. Figure 3 shows the span of the publications across key themes. Table 1 shows the citation analysis across key themes of the systematic literature review. Figure 3: Spanning of the publications under key themes of the review as a percentage. Figure 2: Publication type categorization of the research performed in the field and the number of publications per year from 2001 to 2024. Gaps in converting theoretical developments into practical frameworks, as evidenced by the dispersed approach across themes, significant citation variation, and minimal representation of applied research (few conference proceedings and technical reports). In order to promote complete IoT-based computing solutions in smart cities, this research emphasizes the necessity for standardized, scalable IoT frameworks that incorporate sustainability, artificial intelligence, pollution monitoring, and economic models. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Key Theme** & **Total Citations** & **Mean** & **Standard** & **Mean Citations per** & **Standard Deviation of** \\  & & **Citations** & **Deviation** & **Year** & **Citations per Year** \\ \hline IoT-based urbanized & & 3896 & 194.80 & \(\pm\)631.95 & 24.34 & \(\pm\)50.26 \\ competing automation & & & & & \\ Intelligent composting & 4849 & 138.54 & \(\pm\)343.34 & 28.49 & \(\pm\)64.62 \\ process optimization & & & & & \\ Urban composting & & & & & \\ sustainability & 1964 & 72.74 & \(\pm\)188.74 & 10.53 & \(\pm\)14.59 \\ assessment & & & & & \\ Composting process & & & & & \\ pollution and & 3762 & 163.56 & \(\pm\)306.93 & 28.85 & \(\pm\)40.77 \\ environmental impact & & & & & \\ Cost and life cycle & 3177 & 211.80 & \(\pm\)306.72 & 23.22 & \(\pm\)35.58 \\ analysis & & & & & \\ \hline \hline \end{tabular}
\end{table}