# A Very High-Resolution Urban Green Space from the Fusion of Microsatellite, SAR, and MSI Images
## 4 Discussion  
### Driving Forces and Comparison of Other Existing Products  
The primary driving force behind the creation of large-scale urban green spaces in Jakarta is the governor's policy, particularly Policy No. 9 of 2022 regarding green spaces [35]. This policy aims to ensure that Jakarta allocates 20% of its land to public green spaces and 10% to private green spaces. Activities include enhancing the quantity, quality, and coverage of urban green spaces.  
\begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt}} \hline \hline
**Benefit** & **Description** \\ \hline Environmental Conservation & Green belt areas in Jakarta are primarily established to conserve natural habitats, including forests and wetlands. These areas are vital for maintaining biodiversity and providing habitats for wildlife. \\ \hline Flood Mitigation & Jakarta is prone to seasonal flooding, exacerbated by urban expansion. Green belts act as natural buffers, absorbing excess rainwater and reducing the risk of flooding in the city. \\ \hline Urban Planning and Development Control & Green belt areas serve as a means of regulating urban development. Zoning regulations restrict construction in these zones, ensuring that urban sprawl is controlled and that green spaces are preserved. \\ \hline Recreational and Educational Opportunities & Many green belt areas in Jakarta are open to the public and offer recreational activities such as walking, biking, or bird watching. These spaces also serve as outdoor classrooms for environmental education. \\ \hline Economic Benefits & The preservation of green belt areas can have long-term economic benefits, including improved property values in nearby urban areas, increased tourism, and potential for sustainable agriculture or city ecotourism. \\ \hline \hline \end{tabular}
\end{table}
Table 5: Benefits of Jakarta’s urban green belt.  
The urban green space master plan involves two crucial steps: strategic policy and an action plan. Within the strategic policy, collaboration between the public and government in managing urban green spaces stands out as pivotal. The government pledges financial, human, and technological resources, along with infrastructure and tools for green space management, research, and technical assistance. Meanwhile, the public is encouraged to establish citizen communities or forums to oversee urban green spaces.  
The action plan includes the development of an urban green space database, the revitalization of upstream areas through reforestation and afforestation, and the naturalization of rivers in critical areas. It also entails the restructuring of dense slum settlements along riverbanks, the revitalization of downstream areas through mangrove reforestation, and the monitoring and evaluation of Jakarta's urban green spaces. The implementation of this policy is resulting in an expansion of urban green spaces throughout Jakarta.  
However, according to the official data from the Ministry of Environment and Forestry of Indonesia, Jakarta's urban green space is notably scarce, measuring only 3.254 km\({}^{2}\) as of 2023 [36]. This disparity arises from differing definitions of urban green space. The Ministry defines green space as elongated areas or clusters with open usage, where plants naturally grow or are deliberately cultivated [37]. However, this definition is too narrow. In this study, urban green space is defined more precisely and categorized into five classes: agriculture, forest, grassland, mixed, shrub, and wetland. Other research [38] utilizing data from the Department of Human Settlements for Spatial Planning and Land Affairs of DKI Jakarta Province indicates that Jakarta's urban green space measures only 83.55 km\({}^{2}\). This indicates the urban green space of Jakarta is only 12.6%. This underestimated area of urban green space is due to the data sources referring to different years, different publicly editable sources (open street map), and low-resolution Landsat-8 images.