Advancing urban sustainability: Applying GIS technologies to assess SDG indicators – a case study of Podgorica (Montenegro)

1 Introduction

Sustainable urban development represents a key challenge for modern society, encompassing economic growth, social inclusion, and environmental protection. Elkington [1] introduced the concept of the “Triple Bottom Line,” emphasizing the balance between social, ecological, and economic aspects. This approach enables the enhancement of quality of life in urban areas in a sustainable manner. These principles are included in the 17 sustainable development goals (SDGs) defined by the UN, such as “no poverty,” “decent work and economic growth,” and “life below water.” By adopting the 2030 Agenda, the United Nations set these goals as a universal call to action to end poverty, protect the planet, and ensure prosperity for all [2].

Caiado et al. [3] emphasized the critical role of information and communication technologies and artificial intelligence in achieving the SDGs, particularly through improved data collection and analysis for monitoring progress. Similarly, Guo et al. [4] underscored the value of big data integration for enhancing the precision and comprehensiveness of SDG indicator assessments. Sustainable investments, as examined by Folqué et al. [5], contribute to SDG goals by integrating environmental, social, and governance factors, while Rosati and Faria [6] point to the impact of institutional factors on SDG inclusion in corporate sustainability reports. The study of Topple et al. [7] further illustrated how multinational enterprises align their sustainability practices with international standards, facilitating SDG integration.

In relation to SDG 11.7, research has increasingly focused on the provision of safe, inclusive, and accessible green and public spaces. Studies such as those by Šiljeg et al. [8] have explored the role of urban planning in ensuring equitable access to green spaces, particularly in densely populated areas. Their findings emphasize the need for strategic land use policies and infrastructure development that prioritize marginalized communities. Similarly, Stessens [9] investigated the socio-economic benefits of public spaces, emphasizing their role in fostering social cohesion and well-being.

Hence, Lorenzo-Sáez et al. [10] examined the contribution of green urban areas (GUA) to achieving SDGs in Valencia, concluding that GUAs directly contribute to SDG 11 (Sustainable Cities and Communities), SDG 13 (Climate Action), and SDG 15 (Life on Land). The study reveals that 9.23% of the population lacks desired access to GUAs, while 2.73% lack easy walking access. Valencia has 10 m² of GUA per inhabitant, which is above the recommended 9 m² by the World Health Organization but below the average for European cities. Similar findings were previously reported by Siragusa et al. [11], who emphasize the importance of GUAs in achieving SDG goals, emphasizing their ecological, aesthetic, and recreational value. GUAs act as bioclimatic regulators of humidity and temperature, improving quality of life and public health. Similar results are presented by Elgizawy [12] and Hunter et al. [13], who highlight the contribution of urban green spaces to biodiversity conservation, reduction of urban heat island effects, and reduction of greenhouse gas emissions. Furthermore, Cheshmehzangi et al. [14] concluded that green infrastructures enhance the ecological, social, and economic aspects of urban areas. As pointed out by the given study, they help reduce air pollution, regulate temperature, and increase biodiversity. Green infrastructures are particularly important for underdeveloped areas, where they can significantly contribute to sustainable development by improving quality of life and economic resilience. These green spaces also enhance social cohesion and provide areas for recreation. The work of Tate et al. [15] underscored the contribution of urban green and blue spaces (UGBS) to achieving SDG goals, emphasizing their role in reducing air pollution, regulating temperature, and improving quality of life. The respective authors also claim that UGBS can significantly contribute to achieving SDG 3 (Health and Well-being), SDG 11, and SDG 13. They also emphasize the need for further research on the social and economic benefits of UGBS, especially in low- and middle-income countries. Recent studies [16,17] show that access to green spaces significantly reduces cardiovascular and respiratory diseases, while Barboza et al. [18] study the reduction of mortality associated with pollution and urbanization, concluding that increasing green spaces in urban areas can significantly reduce mortality caused by air pollution and heat stress. The work of Haq [19] emphasizes the economic, ecological, and social benefits of urban green spaces, noting that they improve quality of life by providing spaces for recreation and socialization, contributing to ecological balance and economic development. Hartig [20] emphasized that access to green spaces improves mental health and reduces stress for city residents, while Heidt [21] concluded that vegetation in urban areas improves air quality and reduces noise, positively affecting the quality of life for citizens.

In addition, Hak et al. [22] emphasized the importance of indicators in analyzing SDGs, concluding that precise and well-defined indicators are crucial for tracking progress and identifying areas requiring additional efforts. They suggest improvements in data collection methodologies to ensure greater accuracy and relevance of indicators. One of the key Sustainable Development Goals is SDG 11 - Sustainable Cities and Communities. This goal aims to make cities and human settlements inclusive, safe, resilient, and sustainable. The study by Takase [23] highlights that the expansion of urban land is outpacing the growth of the urban population, which negatively affects the sustainability of urban development. He points out the need to ensure universal access to safe, inclusive, and accessible green and public spaces by 2030, especially for women, children, the elderly, and people with disabilities. These requirements align with SDG 11, which strives for inclusive, safe, resilient, and sustainable cities. Furthermore, he asserts that integrated regional planning is crucial for sustainable urbanization and community empowerment, which is essential for achieving SDGs.

One of the indicators of progress for SDG 11 is indicator 11.7.1, which measures the percentage of open public spaces in relation to the total built-up area of a city. This indicator includes open public spaces such as parks, squares, and green areas and is vital for assessing the quality of life in urban environments. Open public spaces play a crucial role in promoting social interaction, physical activity, and ecological sustainability, making them essential for the sustainable development of cities. A range of studies have explored the application of geographic information systems (GIS) technologies to calculate SDG indicator 11.7. In their research, Mackres et al. [24] developed a framework using global geospatial data to benchmark and track urban changes, emphasizing the integration of diverse data sources. Furthermore, Verde et al. [25] introduced a cloud-based mapping approach employing deep learning and high-resolution Earth observation data to compute the SDG 11.7.1 indicator, which measures access to public spaces in urban areas. Both studies highlight innovative techniques for utilizing geospatial data to improve urban sustainability assessments. This study seeks to answer the following key scientific questions: (1) How can GIS-based methodologies be effectively utilized to calculate SDG indicator 11.7.1 in urban environments? (2) What is the spatial distribution of open public spaces in Podgorica, Montenegro, and how does it compare to the built-up urban area? (3) How can urban planning strategies be enhanced to promote sustainable development by expanding and improving public spaces?

Lami et al. [26] and Choi et al. [27] emphasized the potential of GIS in visualizing and measuring urban sustainability, with Lami specifically discussing the use of GIS in the Italian context. Furthermore, Acharya and Lee [28] and Han et al. [29] provided broader overviews of the use of remote sensing and geospatial technologies in monitoring SDGs, including indicator 11.7. The studies conducted by Aguilar and Kuffer [30] and Blaschke and Kovács-Győri [31] underscored the use of cloud-based computation and Earth Observation data, respectively, in mapping and monitoring urban open spaces. These studies collectively demonstrated the potential of GIS technologies in calculating SDG indicator 11.7, particularly in the context of urban sustainability.

Public spaces in urban areas, such as parks, squares, green areas, and streets, are crucial for the quality of life of citizens and the achievement of SDGs (SDG 11) [32]. These spaces provide opportunities for recreation, social interaction, cultural activities, and ecological sustainability, contributing to the physical and mental health of residents. Studies have shown that access to green spaces can reduce the incidence of cardiovascular diseases and improve mental health [33,34,35]. Active and well-used public spaces are essential for the social life of cities, facilitating interaction among people from different social strata [36,37]. In addition to their social function, green spaces improve air quality, reduce noise, regulate temperature, and preserve biodiversity [38,39]. Well-designed and maintained public spaces also increase property values, attract tourists, and stimulate the local economy. Research indicates that parks and green spaces enhance the value of residential and commercial properties, positively affecting local tax revenues and economic development [40,41,42]. However, many cities face challenges in preserving and expanding public spaces due to urbanization and pressure to construct new buildings [43,44,45]. Urban planners and decision-makers must recognize the importance of public spaces and incorporate their preservation into urban development strategies to achieve the SDGs (SDG 11).

The work of Meier [46] pointed out that there has been a significant decline in the proportion of articles related to the SDGs without directly mentioning them, despite an overall increase in publications that explicitly mention the SDGs. The study reveals a positive correlation between the connection of articles to the SDGs and the number of citations for works published after the adoption of the SDGs in 2015. However, this correlation is positive only for the third sector, while it remains negative for public administration. The author emphasizes the need for further research in public administration to enhance efforts to achieve the SDGs by 2030.

This article presents a GIS-based methodology for calculating SDG indicator 11.7.1 in Podgorica, Montenegro. Utilizing advanced geospatial analysis and precise spatial planning data, the study provides an accurate assessment of open public spaces relative to the city’s built-up area, such as parks, green areas, streets, and squares [47,48]. The objective is to evaluate the distribution of public spaces and guide urban planning strategies that support sustainable development.

By addressing the lack of precise data on public space distribution, particularly in Montenegro [47], this research employs cutting-edge GIS techniques and current spatial datasets to ensure reliable indicator calculations. The methodology offers a replicable framework for urban analysis, addressing gaps in both data accuracy and availability. Moreover, the study emphasizes the critical role of public spaces in enhancing urban quality of life, social integration, and environmental sustainability. Expanding public spaces can significantly improve these aspects. This research supports the operationalization of SDG 11 by providing a rigorous approach to monitoring key urban sustainability indicators.

2 Materials and methods

2.1 Overview of the study area

Podgorica, the capital city of Montenegro, covers an area of 1,389 km². It is located (Figure 1) in the southeast of Montenegro and includes the majority of the Podgorica-Skadar Basin, as well as the northwestern, northern, and eastern parts of the surrounding mountains. Podgorica represents the largest urban agglomeration in the country, with numerous administrative, cultural, educational, and healthcare centers, as well as significant economic capacities. From 1948 to 2023, Podgorica has shown a trend of population growth. The increase in the population of these settlements is largely driven by natural growth but even more so by mechanical growth (migration). In the hilly areas, the population is declining, while in the flatland centers, the population continues to grow. According to the official census of 2023, the population of Podgorica was 179,505 [49,50].

Figure 1

The location of Podgorica city in Montenegro.

In the last two decades, numerous changes have occurred in the demographic and socio-economic development of Podgorica, leading to evident negative processes that threaten and degrade the environment. Following the completion of the privatization process and the unsuccessful restructuring of major industrial economic systems, economic activities in Podgorica have mostly shifted from industry to service sectors. The processes of urbanization and suburbanization have continued. On the contrary, the urban space and natural environment are experiencing various changes, resulting in the degradation of the area [51].

2.3 Data analysis for indicator 11.7.1 and GIS processing

In this study, GIS analysis was applied to assess the proportion of open public spaces in relation to the total built-up area of Podgorica. GIS tools facilitated precise mapping, digitization, and quantification of various categories of public spaces, enabling a comprehensive evaluation of the SDG 11.7.1 indicator. The methodology integrated multiple data sources to ensure accuracy and relevance, combining spatial planning documents, high-resolution satellite imagery, and GIS-based land-use datasets. The GIS-based methodology relied on detailed urban planning documents from the municipal authorities of Podgorica, including the Spatial Plan of the Capital City of Podgorica and the General Urban Plan of Podgorica, which provided essential insights into the size and spatial distribution of public and built-up areas, including parks, squares, and other open spaces. These records were supplemented with high-resolution geospatial datasets from the Urban Atlas program (Copernicus Land Monitoring Service) [52], which enabled fine-scale classification of land use and land cover. To conduct the GIS-based analysis, the study employed QGIS (v. 3.38.0) and SAGA GIS (v. 9.3.1), providing an advanced computational framework for spatial data processing and analysis. QGIS was used for vector-based spatial operations, geoprocessing, and cartographic visualization, including the extraction of public space polygons, computation of their surface area, and segmentation of urban features. In contrast, SAGA GIS facilitated raster-based land classification and advanced spatial modeling, particularly through polygon dissolution for aggregating fragmented land areas and geostatistical interpolation for refining urban delineations. Additionally, the CORINE Land Cover (CLC) database was utilized to analyze historical land use changes between 2000, 2006, 2012, and 2018. This dataset provided a comprehensive record of land cover transformations, enabling the study to evaluate the impact of urban expansion on public space availability. The CLC data was specifically used to validate land use classifications in Podgorica and to ensure consistency with urban development trends observed in other European cities. The integration of these datasets ensured a high level of precision in identifying urban expansion patterns and their influence on public space distribution.

To systematically process and analyze public spaces, a structured geospatial workflow was implemented, allowing for a transparent and replicable approach to SDG 11.7.1 calculation. The first stage involved data acquisition and preprocessing, where various spatial datasets were standardized to a unified coordinate system and georeferenced to match existing cadastral records. This was followed by the digitization and classification of public spaces, where vector-based GIS tools were employed to delineate and categorize open areas, distinguishing between parks, squares, and green spaces. The subsequent stage of spatial analysis and segmentation applied GIS operations such as Clip, Buffer, and Intersect functions to refine the spatial boundaries of public spaces, ensuring an accurate representation of their proportion in relation to built-up land. The CORINE Land Cover dataset was instrumental at this stage, as it allowed for cross-validation of land use trends and provided a historical reference for urban development.

The computation of SDG 11.7.1 was performed using GIS attribute table calculations, where public open spaces (POT) and built-up land (PIG) were quantified to determine their relative proportion. The results indicated that the total area of open public spaces in Podgorica amounts to 1,028 ha, while the total built-up area is 858.49 ha. These calculations resulted in an SDG 11.7.1 value of 119.75%, representing the current availability of public spaces based on high-resolution GIS analyses of real-world conditions. A secondary dataset, incorporating projections for urban expansion and zoning modifications, indicates a future public space coverage of 140%. This discrepancy arises from differences in the data sources: the 119.75% value represents current conditions based on GIS spatial analysis of existing public spaces, while the 140% projection accounts for planned infrastructure developments, green space expansions, and urban reconfigurations as outlined in municipal planning strategies. For methodological transparency, this study prioritizes the 119.75% value as the most accurate representation of the current state, with the 140% figure serving as an indication of the city’s long-term vision for enhancing public space accessibility.

Validation and accuracy assessment were crucial in confirming the reliability of these results. The GIS-derived calculations were cross-verified with field measurements and auxiliary datasets, ensuring alignment with real-world conditions. Previous studies have shown that GIS-based land use quantifications typically achieve an accuracy rate of 85–95% when high-resolution spatial datasets are used [53,54]. To further confirm the robustness of the findings, a comparative analysis with urban areas such as Valencia and Germany, where 9.23% of the population lacks access to urban green spaces [11,55–57], was conducted. These comparisons reinforced the conclusion that Podgorica maintains relatively high public space accessibility, contributing to sustainable urban development.

The final stage of the methodological framework involved thematic mapping and visualization, where GIS-generated spatial representations were used to illustrate the distribution and accessibility of public spaces in Podgorica. This process enhanced the clarity of results and provided an essential tool for urban planners and policymakers seeking to improve public space allocation. By integrating GIS-based methodologies with comprehensive urban planning data, this study contributes to a replicable framework for assessing SDG 11.7.1 and offers practical insights into the sustainable management of public spaces. Future research should explore the integration of remote sensing techniques, such as Sentinel data processed via Google Earth Engine (GEE), to enhance monitoring capabilities and enable broader comparative analyses across multiple urban areas.

Identification and collection of data on open public spaces (POT):

P OT = P parks + P squares + P green spaces + P others ( 1,028 ha )

Identification of the total built-up area of the city (PIG):

P IG = P residential zone + P business zone + P industrial zone + P infrastructure + P other built-up areas ( 858.49 ha )

The calculation of Indicator 11.7.1 was performed based on similar methodologies used by authors such as Han et al. [29], who assessed spatiotemporal changes of SDG indicators using geospatial big data, and Aguilar and Kuffer [30], who improved SDG indicators in open spaces using high-resolution imagery. These studies provide methodological guidelines for calculating and interpreting indicators related to public spaces.

Indicator 11.7.1 is calculated as

Indicator 11.7.1 = ( 1,028 ) 858.49 × 100

Data on public spaces in Podgorica, Montenegro, was gathered and analyzed to provide an in-depth assessment of various spatial categories (in ha), including city streets, green spaces, and other public areas. This analysis was conducted using QGIS (version 3.38.0) and SAGA GIS (version 9.3.1), leveraging advanced GIS tools and techniques to ensure precise and reliable results (Table 2).

Table 2

Steps for calculating Indicator 11.7.1

3 Results

The evaluation of SDG 11.7.1 sub-indicators in Podgorica revealed disparities in accessibility, availability, and quality of public spaces. Table 3 with data on public spaces in Podgorica provides a detailed overview of various categories of areas, including city streets, green spaces, and specific public spaces. Categories such as city bypasses, main city streets, parks, linear greenery, and block greenery represent key segments of public spaces. From the data in the table, we can see that the largest areas are occupied by block greenery (364.584 ha) and other natural areas (673 ha), indicating a significant proportion of green spaces in the urban area of Podgorica.

Figure 2 shows the total areas in three main categories: street areas (171.228 ha), green spaces (624.87 ha), and public spaces (1,028 ha) obtained by the GIS analysis. The significant dominance of green and public spaces emphasizes the ecological and social importance of these areas in the urban environment.

Figure 2

Summary of Podgorica areas by category (x-axis: area in ha; y-axis: category).

Street areas constitute a significant part of the total city area, but their share is smaller compared to green and public spaces. This indicates a relatively balanced approach to urban planning, with priority given to green and public spaces. Green spaces, which dominate Podgorica’s public areas, enhance ecological balance and urban sustainability. This category includes city parks, linear greenery, block greenery, suburban greenery, and undefined non-urbanized areas.

Figure 3 shows the spatial distribution of different types of land in Podgorica, including natural areas, agricultural areas, forest areas, built-up areas, and water areas. Gorica Hill, a prominent feature of Podgorica’s green infrastructure, offers significant ecological and recreational benefits (Figure 3). The integration of such green spaces into urban environments is crucial for sustainable urban development, offering both ecological and social benefits that align with the broader goals of urban sustainability.

Figure 3

Spatial distribution of land use in Podgorica.

The next step was the spatial distribution of water areas in Podgorica, including rivers, lakes, and other water bodies. Using GIS technologies has enabled precise mapping of these areas. According to the GIS analysis, the total area of water bodies is 167,966,537 m². This map (Figure 4) is crucial for assessing the ecological aspects and sustainable development of the city [58].

Figure 4

Spatial distribution of water spaces in Podgorica.

The Morača River quay plays a crucial role in urban livability, serving as both a recreational space and a social hub for citizens. As part of the urban green infrastructure, this waterfront area enhances the aesthetic appeal of the city, promotes social interaction, and provides opportunities for outdoor activities such as walking, jogging, and cycling (Figure 5).

Figure 5

Urban Waterfront: Quay along the Morača River in Podgorica.

The integration of the Morača River quay into the city’s urban design is essential for promoting environmental sustainability by preserving the natural watercourse and surrounding green spaces. This figure illustrates the importance of maintaining and improving urban waterfronts as part of broader urban sustainability efforts. The quay not only contributes to the ecological health of the river but also aligns with SDG 11.7.1, which emphasizes the need for accessible and safe public spaces. By providing a well-maintained and accessible area along the river, the quay enhances the quality of life in Podgorica and serves as a model for integrating natural and urban environments in a sustainable manner.

Njegoš Park is a significant urban green space in Podgorica, providing residents with a natural area for recreation and social interaction. As a central part of the city’s green infrastructure, the park enhances the quality of urban life by offering accessible and well-maintained green areas that support both environmental sustainability and community well-being.

3.1 Calculation of Indicator 11.7.1

Based on the collected and processed data, the calculated value of Indicator 11.7.1 for the Capital City of Podgorica is 119.75%, indicating that the total area of open public spaces surpasses the total built-up area. The total area of open public spaces (POT) is 1,028 ha, while the total built-up area (PIG) is 858.49 ha.

The ratio exceeding 100% suggests that the city has prioritized the inclusion of parks, squares, and green spaces within the built environment. This is a significant finding, as it reflects the potential for enhancing the quality of life in urban areas by providing accessible public spaces for residents. It also points to the importance of maintaining these spaces as integral parts of urban planning to support environmental sustainability and social well-being.

The land use analysis of Podgorica between 2000, 2006, 2012, and 2018 reveals clear shifts in urbanization and land cover, validated using CORINE Land Cover datasets [52]. The percentage of artificial surfaces increased from 2.29% in 2000 to 3.87% in 2006, 5.12% in 2012, and 6.46% in 2018. This significant growth indicates the expansion of urban areas, infrastructure, and residential zones, which is consistent with the CORINE data (Table 4).

Table 4

Land cover distribution using CORINE land cover datasets (2000–2018) [52]

Code	Land cover types	2000 (in km2)	2006 (in km2)	2012 (in km2)	2018 (in km2)
1.	Artificial Surfaces	31.85	82.54	87.15	89.84
2.	Agricultural areas	297.85	265.51	262.24	263.81
3.	Forest and seminatural areas	998.16	979.49	977.56	974.43
4.	Wetlands	52.48	52.22	51.15	51.02
5.	Water bodies	8.94	9.52	10.18	10.18
SUM (km2)		1389.28	1389.28	1389.28	1389.28

Agricultural areas decreased from 21.44% in 2000 to 20.12% in 2006, 19.45% in 2012, and 18.98% in 2018, reflecting a continuous shift from agricultural land to built-up areas. This trend aligns with the CORINE datasets, where agricultural land is gradually being replaced by urban development.

The percentage of forest and seminatural areas declined from 71.93% in 2000 to 71.20% in 2006, 70.85% in 2012, and 70.22% in 2018. CORINE data confirms a gradual reduction in forested areas due to urban expansion (Figure 6).

Figure 6

Land cover map of the study area (2000–2018) based on CLC datasets [52].

Wetlands remained largely stable, with a slight decrease from 3.78% in 2000 to 3.74% in 2006, 3.69% in 2012, and 3.67% in 2018. The CORINE validation supports this finding, showing little impact on wetland areas despite urbanization.

Finally, water bodies showed a minor increase from 0.64% in 2000 to 0.67% in 2006, 0.71% in 2012, and 0.73% in 2018. This change likely reflects adjustments in water infrastructure or the creation of new artificial water bodies, as indicated by the CORINE data. Overall, forests have remained largely stable, while wetlands and water bodies have seen minimal changes. These results align with those from Indicator 11.7.1, which suggested an increase in open public spaces amidst urban pressures.

4 Discussion

The results of the analysis show that the proportion of open public spaces in relation to the total built-up area of Podgorica is approximately 119.75%. This finding indicates a relatively high percentage of public spaces, which can significantly contribute to the city’s sustainable urban development. The key contributions of this research are reflected in three main aspects: ecological, social, and economic.

The ecological significance of open spaces is evident in their role in reducing the urban heat island effect, improving air quality, and preserving biodiversity. These spaces support natural ecosystems within the urban environment, providing habitats for various plant and animal species. The analysis of land use data from 2000, 2006, 2012, and 2018 indicates significant changes in the spatial structure of the city. For example, the share of urbanized areas increased from 2.29% (2000) to 6.46% (2018), while agricultural land decreased from 21.44 to 18.98% [53,54]. These changes highlight the ongoing urbanization process and the necessity of preserving and planning open public spaces to maintain ecological balance.

The social dimension of public spaces confirms their importance in strengthening social cohesion and improving the quality of life. Parks, squares, and recreational areas serve as gathering and interaction points, fostering a sense of community and reducing social isolation [59–62]. These findings align with the study of Meier [46], which emphasizes the importance of social aspects in urban planning for achieving SDGs.

From an economic perspective, the results confirm that well-maintained public spaces contribute to increased property values in their vicinity, attract tourists, and stimulate local economic activities [63]. Specifically, Njegoš Park and the Morača River waterfront serve as key points that attract visitors, enhance Podgorica’s tourism offerings, and generate revenue for the local hospitality and tourism industries.

Accurate GIS calculations allow for the quantification and mapping of these spaces, providing a foundation for future urban planning decisions. A comparison with previous studies shows that results vary significantly depending on the local context. For instance, studies conducted in Valencia and Germany indicate that 9.23% of the population lacks adequate access to urban green spaces, while the SDG 11 goal fulfillment rate in Germany ranges between 18 and 27%, depending on the indicators used [11,55–57]. Our analysis suggests that Podgorica has a relatively high percentage of public spaces compared to other cities, but for a more precise comparison, standardized methodological approaches should be used.

GIS analyses confirm that accurate mapping of public spaces can be used to monitor progress towards SDGs. The study of [64] shows that 31% of SDG-related research originates from the USA, China, and the UK, highlighting the need for a global approach to urban space analysis. Similarly, [65] analyzed investments in sanitation improvements in Algeria, emphasizing resource management challenges, which is relevant to our study in the context of public and green spaces in Podgorica (Montenegro).

Precise mapping of urban spaces using satellite data and deep learning has shown a high degree of accuracy in previous studies. For instance, GIS models based on OpenStreetMap data achieved 67.38% overlap, while deep learning models demonstrated great potential for mapping urban open spaces despite some commission errors [66]. A study conducted in Kampala found that open spaces decreased by 125 m² per capita over 8 years, while classification models used in the global human settlement layer achieved an accuracy of up to 88% [28,67,68].

5 Concluding remarks

This study demonstrated the importance of accurate data collection and GIS-based analysis in assessing open public spaces for the sustainable development of urban areas. Using GIS technologies and spatial planning documents, we calculated that the share of open public spaces in the total built-up area of Podgorica is approximately 119.75%. These results emphasize the ecological, social, and economic importance of public spaces in urban environments. By applying GIS methodologies, this study provides a framework that can serve as a model for other cities seeking to improve their public spaces and promote sustainable urban development.

The findings contribute to the theory of urban planning and sustainable development, particularly in demonstrating the effectiveness of GIS technologies in the precise mapping and quantification of public spaces, essential for accurate monitoring of SDG indicator 11.7.1. The integration of GIS analysis with detailed spatial planning documents allows for a comprehensive assessment of urban public spaces, offering a methodological contribution that can be applied in future urban sustainability research.

From a practical perspective, this study provides valuable insights for urban planning and policymaking, emphasizing the need for data-driven decision-making in managing public spaces. The research findings can assist urban planners and local authorities in defining policies that support sustainable urban development, improve public space accessibility, and enhance the quality of life for residents. Furthermore, comparative analysis with other cities could help identify best practices and offer guidelines for further improvements in urban space management.

Despite the significant contributions of this study, several limitations should be considered. First, the accuracy of GIS-based analyses is inherently dependent on data availability and quality. Potential classification errors in land use datasets could impact the precision of calculated indicators. Second, this study relied on data spanning from 2000 to 2018, with limited historical data availability, which restricts the ability to analyze long-term trends in urban public space development. Third, while field data was used to validate GIS calculations, expanding field surveys and integrating real-time monitoring systems could further enhance the reliability of findings.

Future research should expand on this work by incorporating remote sensing techniques, such as medium-resolution satellite imagery (e.g., Sentinel data) through the GEE platform, to improve the precision and scalability of urban area assessments [69]. Additionally, extending this analysis to multiple cities would provide a broader perspective and enable comparative studies that can support more generalized policy recommendations for sustainable urban planning [70].

By integrating GIS-based methodologies, historical land use analysis, and real-time remote sensing data, future studies can further refine the monitoring of SDG indicators and contribute to the effective management of urban public spaces in alignment with global sustainability goals.