Crude oil is a major energy resource; however, oil exploration and production activities may release petroleum hydrocarbons (PHCs), heavy metals, and other contaminants that can adversely affect groundwater quality. This study evaluates the quality of groundwater surrounding oil mining sites in Musi Banyuasin Regency, South Sumatra, Indonesia, using the Water Quality Index (WQI) method. Groundwater samples were collected from 36 sampling points, consisting of 30 study wells located near oil drilling areas and six control wells, with two control wells in each of the three sub-districts: Sanga Desa, Babat Toman, and Lawang Wetan. The analyzed parameters included pH, temperature, total dissolved solids (TDS), turbidity, color, and heavy metals, including copper (Cu), nickel (Ni), lead (Pb), and mercury (Hg). The physicochemical and heavy metal data were processed and analyzed using Python, and the WQI was calculated to determine the overall groundwater quality classification. The results indicated that all 30 study wells (100%) were classified as unfit for consumption, whereas all six control wells (100%) were classified as excellent based on the WQI classification. The primary contaminants contributing to poor groundwater quality were Ni, Pb, and Hg, which exceeded the applicable national groundwater quality standards at several sampling points. Elevated concentrations of TDS, turbidity, and color were also observed at several study wells. These findings demonstrate a substantial anthropogenic influence of oil exploration activities on groundwater quality in the study area. Continuous groundwater monitoring, improved pollution control, and appropriate environmental management by relevant authorities are therefore essential to minimize contamination and prevent further degradation of groundwater resources.

The increasing demand for electrical energy and the commitment to clean energy transition encourage the utilization of renewable energy at the community level through the development of solar photovoltaic (PV). This study aims to identify the potential of solar PV, design the generating system, and analyze the technical and economic feasibility of developing an energy-independent village based on microgrids in Kedungrong Hamlet, Yogyakarta Special Region. The study uses a descriptive quantitative approach with the research object being 53 houses’ rooftops identified as having the potential for installing rooftop solar power plants (PLTS). Primary data were obtained through field observations, inventory of roof area and household electricity needs, and technical documentation, while secondary data were obtained from Global Solar Atlas and relevant scientific literature. The analysis was carried out through identification of solar radiation potential, calculation of electricity consumption, design of solar panel capacity and its supporting components, and evaluation of economic feasibility based on initial investment and energy saving benefits. The results of the study indicate that the rooftops of 53 buildings in Kedungrong Hamlet have good potential to be developed as PLTS systems because they are supported by adequate solar radiation intensity throughout the year. Economic analysis shows that PV investments provide benefits in the form of electricity cost savings and have a viable long-term return on investment. The integration of rooftop PV through a microgrid system improves energy supply reliability, electricity distribution efficiency, and strengthens community energy security. This research produces an energy-independent village planning model based on the utilization of 53 rooftops as a source of renewable electricity generation that can be replicated in other rural areas with similar characteristics to support the achievement of the national energy mix and sustainable development.

Pulau Weh, with Sabang as its capital, is located at the westernmost tip of Indonesia. Beyond its significance for domestic and international tourism, the island hosts several national strategic projects. Currently, the landscape of Pulau Weh is dominated by non-urban areas (agriculture, forests, and open land), including critical conservation and protected forest zones. These areas provide essential Cultural Ecosystem Services (CES) that benefit the local island community. This study aims to analyze land-use changes and local community perceptions of CES values within the forest conservation areas of Pulau Weh, Aceh Province. The research aligns with the Sustainable Development Goals (SDGs), specifically Goals 1 (No Poverty), 11 (Sustainable Cities and Communities), and 13 (Climate Action). A mixed-methods approach was employed, integrating ArcGIS analysis to evaluate spatial functional changes and statistical analysis using Principal Component Analysis (PCA) via SPSS to measure public perception. The results indicate that the 2023 land-use composition comprises built-up areas (497.69 ha; 4.49%), woodlands (5,203 ha; 46.89%), agricultural land (3,111 ha; 28.04%), grasslands (2,071 ha; 18.67%), water bodies (157 ha; 1.41%), and bare land (55.76 ha; 0.50%). Based on community perceptions, the forest conservation areas in Sabang contribute significantly to CES values, including recreation, cultural heritage, aesthetics, education, social relations, health, spirituality, and ecological/tourism benefits. Notably, disaster mitigation was the only value perceived as non-significant by the community.

Greywater waste is a type of wastewater that comes from bathroom water, washing that enters the drainage system, and is supplemented with rainwater whose downstream flow enters the river. This research aims to enhance the effectiveness of greywater treatment by using a physical model comprising a treatment process, namely a cattious wetland filter. This study applied the vetigenetic wetland method with and without media. The observed research variables were wastewater discharge variations, wetland residence time at intervals of 2 days, 4 days and 7 days, and the number of vetinous root stems, as well as water quality parameters (Y) consisting of pH, odor, color, turbidity, total dissolved solids (TDS), nitrate (NO$_3$$^-$), nitrite (NO$_2$$^-$), fecal coliform, and iron (Fe). The data analysis was based on descriptive evaluation of water quality parameters under different operational conditions, including variations in hydraulic retention time, flow rate, and plant density. The study is expected to show that using a physical model of a media-filtration root wetland can improve wastewater quality, with the output meeting clean-water quality standards that will be used as input to the pond. The qualified water quality consists of pH (7.9), NO$_3$$^-$ 2.319 mg/L, NO$_2$$^-$ 0.0922 mg/L, Fe 0.0286 mg/L, and the unqualified water quality consists of: odor 0.77, color 10.6 true colour units (TCU), turbidity 5.44 nephelometric turbidity units (NTU), TDS 175 mg/L, fecal coliform 85 colony‑forming unit (CFU)/100ml. The output comprises five parameters that do not meet treated effluent quality standards and will be used as inputs to the pond; therefore, further research on phytoremediation is warranted. A constructed wetland using vetiver grass effectively cleans fishpond greywater and reduces pollutant levels. This means it could be used as an initial or final step in water treatment when reuse is limited. However, in this study, the treated water didn’t always meet all health standards. This suggests extra treatment steps are needed, along with more real-world testing to ensure safety.

This article analyses the energy transition trajectories of 25 African countries, combining machine learning and econometric methods. Initially, a Dynamic Time Warping (DTW)-based partitioning approach is used to divide countries into three groups with distinct socio-economic and energy profiles. The Light Gradient Boosting Machine (LightGBM) model is then used to evaluate the significance of macroeconomic and structural variables. A Panel Autoregressive Distributed Lag (Panel ARDL) model is then applied to each group to examine the short- and long-term relationships between macroeconomic and structural variables and renewable energy consumption. The results demonstrate consistency in the importance of variables identified by a Long Short-Term Memory (LSTM) model and their long-term effects within the Panel ARDL framework, thereby showcasing the robustness of the approach. The analysis reveals different dynamics: the first group is hindered by macroeconomic vulnerabilities such as financial instability and high debt, whereas the second group enjoys more favourable conditions. These results provide a basis for developing policies tailored to the specific contexts of each group to accelerate the energy transition in Africa. Thus, the study contributes to a better understanding of the key factors and helps to guide sustainable development strategies on the continent.

The catastrophic 2021 eruption of Mount Semeru severely degraded local ecosystems, necessitating rapid pioneer vegetation establishment to restore landscape stability. While conventional satellite imagery often obscures critical micro-scale ecological interactions, ultra-high-resolution unmanned aerial vehicles (UAVs) provide an unprecedented tool for assessing post-disaster resilience. This study aimed to quantify the multitemporal recovery rate and model the micro-topographic constraints dictating the spatial heterogeneity of pioneer colonization. A 127.08-ha primary lahar corridor within Volcanic Hazard Zone III was mapped using UAVs (2.7 cm/pixel) over a three-year period (2022, 2023, 2025). Vegetation cover was extracted using the Excess Green (ExG) index and automated Otsu thresholding. The methodology was rigorously validated using 300 multitemporal ground-truth points, yielding an overall accuracy of 93.00%, an F1-score of 0.933, and a Cohen’s Kappa coefficient of 0.860, confirming exceptional classification reliability. Post-classification spatial analysis revealed a net positive vegetation expansion rate of +1.88 ha/year, indicating a successful transition from initial colonization to ecological stabilization. However, recovery was profoundly heterogeneous, governed entirely by geomorphological constraints rather than uniform macro-climatic factors. Population-based zonal statistics identified significant ecological preferences for higher peripheral elevations (mean 3,081.0 m), gentler slopes acting as natural seed traps (45.5°), and Southwest-facing aspects that provide essential micro-climatic buffering against equatorial desiccation. These findings offer a strategic paradigm shift for environmental management, recommending that artificial restoration and erosion control interventions in active stratovolcanoes be precisely targeted at these highly resilient micro-topographical hotspots to accelerate the formation of a natural biological shield.

This study assesses the degree to which adaptive governance principles are incorporated into four regional development planning documents of North Sumatra Province, aiming to manage the increasing energy crises and climate threats. Four aspects of adaptive governance are included in the analysis using a document-based evaluation framework: (1) reactivity to uncertainty; (2) scenario-based projection; (3) flexibility of development indicators; and (4) institutional coordinating capacity. The 2025–2045 Regional Long-Term Development Plan (Rencana Pembangunan Jangka Panjang Daerah, RPJPD), the 2025–2029 Technocratic Draft of the Regional Medium-Term Development Plan (Rencana Pembangunan Jangka Menengah Daerah, RPJMD), the 2024–2026 Regional Development Plan (Rencana Pembangunan Daerah, RPD), and the Development Planning Agency’s 2024–2026 Strategic Plan are among the documents examined. Document content was categorized using a qualitative thematic coding process in relation to the assessment matrix. The findings show that planning is still technocratic and linear, lacking institutional tools to facilitate adaptive decision-making, risk-responsive indicators, and alternative scenarios. This disparity indicates that the planning tools required to anticipate crisis-driven disruptions in the energy and environmental sectors are not aligned with the sustainability agenda. In order to improve provincial readiness and hasten the achievement of Sustainable Development Goals (SDGs) 7, 13, and 16, the study suggests integrating risk-based planning, dynamic performance indicators, and cross-sector institutional platforms.

In this research, both Synthetic Aperture Radar (SAR) and optical satellite data are used independently to evaluate the urban expansion, thermal change (Land Surface Temperature (LST)/Urban Heat Island (UHI)), and particulate air quality (PM$_{10}$) ten-year forecasts for Dehradun, Uttarakhand, India for the decade 2014–2024. The Sentinel-1 C-band SAR data (backscatter amplitude $\sigma^{\circ}$ and interferometric coherence $\gamma$) provide a cloud-penetrating and structurally-based evaluation of urban extent. The data used include Landsat-8 OLI/TIRS, which are used for supervised classification of land use and land cover (LULC) by maximum likelihood. The maximum likelihood classification (MLC) and LST retrieval using Mono-Window Algorithm (MWA). The both sensors are processed through independent analytical pipelines and offering corroborating lines of evidence for urban change. The results show important environmental changes: There was an increase in urban area of +28.3 km$^2$ (+3.9%). agricultural land increased by +55.9 km$^2$ (+8.15%), while forest cover declined sharply by -83.1 km$^2$ (-12.05%)—figures with area adjusted uncertainty estimates. The mean LST increased by $\sim$+3.0 °C over the study transect, with mean annual air temperature rising from 21.22 °C to 24.21 °C (+14.1%), which is in line with the rise in temperature at the station, confirming intensification of the Surface Urban Heat Island (SUHI). The concentration of PM$_{10}$ at all the three Central Pollution Control Board (CPCB) monitoring stations it was consistently found that levels of SO$_2$ exceeded the national annual standard for India (60 $\mu$g/m$^3$) by 2.5–2.7 times throughout the study period. These are analyzed in a framework of Environmental Impact Assessment (EIA), which links to Identified land cover change to environmental impact pathways, management implications and policies Himalayan Mountain cities suggestions for urban planning, green space protection and air quality control.