Search

This study explores the dynamics of urban green spaces in five major Indonesian cities—Central Jakarta, Bandung, Yogyakarta, Surabaya, and Semarang—using Sentinel-2 satellite imagery and vegetation indices, such as NDVI and EVI. As major urban areas expand and become more densely populated, development activities have significantly altered urban green spaces, necessitating comprehensive mapping through remote sensing technologies. The findings reveal significant variability in green space coverage among the cities over three periods (2019–2020, 2021–2022, 2023–2024), ensuring that the findings are comprehensive and up to date. This study demonstrates the utility of remote sensing for detailed urban analysis, emphasizing its effectiveness in identifying, quantifying, and monitoring changes in green spaces. Integrating advanced techniques, such as NDVI and EVI, offers a nuanced understanding of urban vegetation dynamics and their implications for sustainable urban planning. Utilizing Sentinel-2 data within the Google Earth Engine (GEE) framework represents a contemporary and innovative approach to urban studies, particularly in rapidly urbanizing environments. The novelty of this research lies in its method of preserving and enhancing green infrastructure while supporting the development of effective strategies for sustainable urban growth. [ABSTRACT FROM AUTHOR]

Indonesia is an archipelagic country located on the equator. The issue of climate change has become a global issue that has impacted several sectors in Indonesia recently. The presence of the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) has contributed to conducting studies on flood and drought events. This review paper summarized 16 published papers that have gone through peer-review, both in the form of publications in journals and at conferences. Since the release of the IPCC AR5 to date, ten studies on flooding and six studies on drought events have been conducted. The most publications on this in 2019 were five publications. Of the various types of the Representative Concentration Pathway (RCP) scenarios used with various methods, the most widely used scenario RCPs is RCP4.5. From the climate change scenario, precipitations parameter is the main parameter that is used in assessing flood or drought events. There are studies conducted on a district / city, provincial scale, and some are even carried out on a watershed scale. The location or province that most flood studies have been carried out is in the capital of Jakarta. The results of these studies generally indicate that the incidence of floods and droughts will increase in the future. Therefore, adaptation steps are needed to deal with unfavorable conditions in the future. Moreover, as the capital city, Jakarta has been estimated that the projected flood incidence will increase. Several publications have provided steps to deal with these challenges on the positive side. [ABSTRACT FROM AUTHOR]

Mineral wool has been used as a filter medium that reaches approximately 95% removal efficiency of total suspended solids (TSS) on a laboratory scale. However, there is no research available has been applied on a larger scale. Hence, this study investigated the ability of mineral wool to remove TSS in two separate segments of the Cikapayang River at different seasons. This analysis utilizes a mineral wool type I, with a dimension of 180×30×120 cm placed in segment 2, and a mineral wool type II with a dimension of 325×30×100 cm placed in segment 9. Samples were taken using the grab sampling method to analyze the TSS concentration before and after being filtered by mineral wool. This investigation concluded that mineral wool could reduce the TSS concentration by up to 65%, and the removal capacity increased by about 6.82% during the dry season. The concentration of TSS in the dry season positively correlates with the increase in the removal capacity of the media. Mineral wool of type I in segment 2 had a better removal ability (31.43%) than type II in segment 9 (14.71%). This research shows that mineral wool can be used as a support material in sanitation sites in large cities experiencing quality degradation in their water bodies. [ABSTRACT FROM AUTHOR]

Jaboi geothermal project experiences a long delay since its concession winning bidder declared in 2008. Based on the latest study, Jaboi geothermal resource can produce up to 40 MW electricity. However, resource location in an isolated grid island that has limited electricity demand is the constraint for its development. In the current study, we propose a conceptual design of a geothermal power plant adapted the load profile in an isolated electricity grid such as in Sabang City, Weh Island, in Indonesia. The electricity generated in the island is not able to be transmitted to the main island of Sumatra. Therefore, to be viable the power plant must be designed to follow the demand existed on the island. To design a demandbased power plant, we perform a thermodynamic analysis of a geothermal binary cycle by using Engineering Equation Solver (EES) software. The optimal flow rate of geothermal fluid required to meet the demand is determined. The simulation results reveal that to produce a 3 MW net power output geothermal binary power plant, it requires a total of 95 kg/s geothermal fluid mass flow rate. Theoretically, this mass flow rate can be supplied from one production well. Therefore, a welldoublet system consisting of a production and re-injection wells can be deployed as the most economic option. [ABSTRACT FROM AUTHOR]

The Hydrologic Engineering Center-Hydrologic Modeling System (HEC-HMS) model can be applied to simulate hydrological processes. This model has been widely used in recent days because it is openly accessible to the public. The search result from this study identifies 180 cases discussing the model applications in Indonesian watersheds in peer-reviewed journal articles and conference papers. The model has been used in Indonesia since 2005, but the highest application is in 2020 with 42 articles. In the context of application distribution, Java Island ranks first place with 123 scientific publications. However, the HEC-HMS model is predominantly used to simulate the "Small" and "Very Small" watershed size categories. The availability of insufficient field data is huge obstacle for hydrological modeling in Indonesia. Furthermore, the model may be extended to address the issues in Indonesia's eastern watersheds. Moreover, the model also can be used to assess the impact of climate change on streamflow. [ABSTRACT FROM AUTHOR]