The application of remote sensing data has been significant in modeling soil erosion. However, previous studies have fallen short in elucidating and lacked an understanding of the multifactor influencing erosion. This study addresses these limitations by employing the InVEST and the Geodetector models. Specifically, it aims (1) to delineate both spatial and temporal variations in soil erosion within the Citarum watershed from 2010 to 2020, (2) to identify the key drivers of soil erosion and unravel the underlying mechanisms, and (3) to identify the high-risk zones for soil erosion. Both models consider a range of natural predictors, including topography (slope factor), climate (precipitation factor), and vegetation cover (vegetation factor). In addition, they incorporate social parameters such as income per capita and population density, which interact with the watersheds position in the downstream, middle, and upper streams. The results reveal that, over a decade, the average soil erosion increased by 15.50×10⁶ tons, marking a 16.65 surge. The impact of factors varies significantly across different subwatershed areas. For example, fraction vegetation cover interactions influence upper- and middle-stream regions, while the downstream area is notably affected by precipitation interactions. The high-risk erosion areas in the watershed are primarily influenced by slope, precipitation, and fractional vegetation cover. In these areas, factors causing high erosion risks include slope, precipitation, and other environmental variables categorized into strata. The study highlights the varying influential factors in different watershed areas.

This study investigates the sustainability of potential small hydropower sites within the Citarum Watershed in West Java, Indonesia. The Citarum River, with a catchment area of 6,090 km2, plays a crucial role in regional water supply and hydroelectric power generation. However, environmental challenges such as deforestation, land use changes, and sedimentation pose significant risks. We employed the CA-Markov model integrated with IDRISI TerrSet software and the Soil and Water Assessment Tool to predict future land use changes and assess water supply, soil erosion, and sedimentation impacts for 2030 and 2040. The analysis revealed diverse trends in water yield across different catchment areas, with some regions showing increased water availability and others facing declines. High erosion and sedimentation rates were identified as critical issues affecting hydropower efficiency. The study highlights the need for comprehensive watershed management strategies, including reforestation, sustainable land management practices, and sediment management, to enhance the sustainability of small hydropower projects. Our findings underscore the importance of integrating environmental considerations into hydropower development to ensure the ecological integrity of the Citarum Watershed.

Hydropower is a critical renewable energy technology with the potential to contribute significantly to the global clean energy transition. However, despite its many advantages, hydropower development faces complex sustainability challenges, including environmental degradation, social displacement, and fluctuating economic returns. These challenges highlight the need for a comprehensive assessment of hydropower projects across multiple dimensions of sustainability. This study aims to evaluate the sustainability of hydropower by conducting a Systematic Literature Review (SLR) of 65 peer-reviewed articles published between 2012 and 2022. It follows Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards to analyse key environmental, social, economic, technical, and policy barriers to sustainable development. The review systematically examines findings from these studies, identifying recurrent themes and critical barriers. The results reveal that while hydropower can enhance energy security and reduce carbon emissions, its implementation often leads to ecological disruption, community displacement, and varying economic benefits. The study underscores the necessity for robust policy frameworks, advanced technologies, and greater stakeholder engagement to mitigate these negative impacts and promote the sustainable development of hydropower.

Rapid land use and land cover (LULC) changes in densely populated watersheds pose serious challenges to the sustainability of ecosystem services (ES), yet their spatially explicit economic consequences remain insufficiently understood. This study analyzes the spatio-temporal dynamics of LULC and ecosystem service values (ESVs) in the Citarum Watershed, Indonesia, one of the country’s most critical and intensively transformed watersheds. Multi-temporal Landsat imagery from 2003, 2013, and 2023 was classified using a Random Forest algorithm, while future LULC conditions for 2043 were projected using a Multi-layer Perceptron–Markov Chain (MLP–MC) model under three scenarios: Business-as-Usual (BAU), Protecting Paddy Field (PPF), and Protecting Forest Area (PFA). ESVs were quantified at multiple spatial scales (county, 250 m grids, and 100 m grids) using both the Traditional Benefit Transfer (TBT) method and a Spatial Benefit Transfer (SBT) approach that integrates biophysical indicators with socio-economic variables. The contribution of LULC transitions to ESV dynamics was further assessed using the Ecosystem Service Change Intensity (ESCI) index. The results reveal substantial historical forest and shrubland losses, alongside rapid expansion of settlements and dryland agriculture, indicating intensifying anthropogenic pressure on watershed functions. Scenario analysis shows continued degradation under BAU, limited mitigation under PPF, and improved forest retention under PFA; although settlement expansion persists across all scenarios. Total ESV declined from USD 2641.33 million in 2003 to USD 1585.01 million in 2023, representing a cumulative loss of 46.13%. Projections indicate severe ESV losses under BAU and PPF by 2043, while PFA substantially reduces, but does not eliminate economic degradation. ESCI results identify forest and shrubland conversion to settlements and dryland agriculture as the dominant drivers of ESV decline. These findings demonstrate that integrating multi-scenario LULC modeling with spatially explicit ESV assessment provides a more robust basis for ecosystem-based spatial planning and supports sustainable watershed management under increasing development pressure.

Water conservation (WC) is a vital ecosystem service (ES) that plays an essential role in the sustainable management of water resources and ensures ecological security. This research examines the WC capacity of the Citarum watershed in West Java Province, Indonesia, from 2010 to 2020. The specific objectives of this research are as follows: (1) to assess the 10-year temporal and spatial variations of WC using the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) and topographic index model; (2) to analyze the temporal interchange between WC and its influencing factors through the Spatial Elastic Coefficient Trajectory Model (SECTM); and (3) to determine the driving factors (DFs) affecting WC by applying Multiscale Geographically Weighted Regression (MGWR). Key findings of this study reveal significant trends in WC from 2010 to 2020: the average WC in the Citarum watershed decreased from 513.96 mm/ha to 453.64 mm/ha (11.74%), indicating a concerning decline in ES capacity. This study also noted that regions implementing comprehensive regulations dominated the study area, covering approximately 72.70% of the total area (502,295 hectares). This illustrates that the implementation of rules plays a crucial role in the WC. Lastly, the MGWR analysis found that WC in the Citarum watershed positively correlated with topography, climate, and vegetation while negatively correlating with socioeconomic factors. This indicates that WC levels are generally lower in areas with higher human activity and economic growth, highlighting the impact of anthropogenic pressures on natural resources. This framework helps stakeholders plan to ensure sustainable development in the area, as it provides valuable insights into the interactions between the ecological and socioeconomic factors affecting WC.

The geological map shows that the Mount Endut area possesses a geothermal system, which is suggested by the presence of geothermal surface manifestations: the Cikawah and Handeleum hot springs. The existence of a subsurface geological fault structure along the manifestations creates good permeability for the geothermal reservoir. The purpose of this study was to utilize Global Gravity Model plus (GGMplus) gravity satellite data to prove the existence of a geological fault structure around the manifestation area with the first horizontal derivative (FHD) and second vertical derivative (SVD) methods; then, we developed a conceptual model of the geothermal system from the 3D-inversion gravity method. Results show a cap suspected of being clay, with a density of 2.52–2.58 g/cm3 at depth of 0–1250 m. The reservoir layer was suspected to be lava rock with a density of 2.60–2.66 g/cm3 at a depth of 1500–3000 m; also, the heat source layer was suspected to be an igneous intrusion with a density of 2.70–2.72 g/cm3 at depth of 1750–3000 m.