Jurnal Presipitasi: Media Komunikasi dan Pengembangan Teknik Lingkungan
Jurnal Presipitasi (P-ISSN: 1907-817X and E-ISSN: 2550-0023) is a peer-reviewed academic journal published by the Environmental Engineering Departement, Faculty of Engineering, Universitas Diponegoro, Indonesia, and has been in continuous publication since 2006. The journal serves as a scholarly platform for the dissemination of original research articles and state-of-the-art review papers in the fields of Environmental Science and Environmental Engineering. Jurnal Presipitasi is nationally accredited under the National Journal Accreditation system (ARJUNA), managed by the Ministry of Research and Technology/National Research and Innovation Agency (RISTEK–BRIN), and is currently ranked in the Second Grade (SINTA 1). The official short title of the journal is J. Presipitasi. Since 2026, the journal has also been indexed in Scopus with an SCImago Journal Rank (SJR) of 0.138 and categorized in Quartile 4 (Q4). Scholars and practitioners who are interested in contributing to the journal’s academic community as reviewers or editors are kindly invited to visit the following link for further information. Publications schedule: March, July, November | more info Language: English Article Processing Charges: please see the following link | more info Indexing: SCOPUS, DOAJ, SINTA, Google Scholar, etc. | more info Ready to submit your manuscript? Please follow [Author Guidelines] Contact: presipitasi@live.undip.ac.id For Hardcopy Order: more info
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State of The Art Evolution of Adsorption Wastewater From Crude Palm Oil Industries
Wastewater from crude palm oil production is among the most concentrated agro-industrial effluents, characterized by very high organic loads, suspended solids, and variable composition. Conventional treatments often struggle to consistently remove recalcitrant pollutants, such as phenolics, colored compounds, and emulsified oil. As a result, adsorption has gained global attention as a versatile and efficient alternative method. This review summarizes the recent advances in adsorption technologies for crude palm oil wastewater treatment. This review highlights the progress in adsorbent development, including biochar, mineral composites, layered double hydroxides, magnetic hybrids, and other engineered materials. The key removal mechanisms for organics, nutrients, and colloids are examined, alongside insights from kinetic, isotherm, and thermodynamic studies. The integration of adsorption with biological, membrane, and oxidation processes is also discussed, demonstrating improved removal efficiency and enhanced effluent stability compared to individual processes. Major challenges remain, particularly in terms of mechanical stability, regeneration, competitive adsorption, and large-scale validation. Future research should prioritize process intensification, sustainable regeneration methods, circular economy-based adsorbent production, and life cycle assessment. Overall, adsorption represents a promising pathway toward more sustainable and reliable crude palm oil wastewater management
Copyright 2026 Jurnal Presipitasi : Media Komunikasi dan Pengembangan Teknik Lingkungan http://creativecommons.org/licenses/by-nc-sa/4.0
Granulated Biochar–MMT–Zn/Al LDH Composite as a Durable Adsorbent for Column Applications
Granular adsorbents are essential for fixed-bed column systems because they reduce the pressure drop and minimize the material loss commonly associated with powdered adsorbents. However, transforming powdered materials into mechanically stable granules without compromising their structural integrity remains a significant challenge. In this study, a granulated composite consisting of biochar, montmorillonite (MMT), and Zn/Al layered double hydroxide (LDH) was developed as a potential adsorbent for column application. Biochar derived from Avicennia marina biomass was combined with MMT and Zn/Al LDH to produce a composite material, which was subsequently granulated using bentonite, tapioca starch, and polyvinyl alcohol (PVA) as binding agents. The resulting granules (0.5–1.5 cm in diameter) were evaluated for mechanical durability under static water immersion and dynamic water flow conditions. The results indicate that the binder composition strongly influences granule stability. Granules prepared without PVA rapidly disintegrated in aqueous environments, whereas the inclusion of PVA significantly improved structural durability. The optimized formulation exhibited durability of up to 8208 min under static conditions and maintained its structural integrity under continuous water flow. These results demonstrate the potential of Biochar–MMT–Zn/Al LDH granules as durable adsorbents for fixed-bed column water treatment systems
PM2.5 Temporal Pattern in Jambi City: Meteorological Drivers and Air Mass Trajectory Analysis
Air pollution, particularly particles with a diameter of less or equal than 2.5 micrometers (PM2.5), has become an important global health and environmental problem. Jambi City in Sumatra is highly susceptible to this issue, both locally and particularly influenced by forest fires. As early studies were conducted over a short period, this study examined the meteorological factors that influenced PM2.5 levels and estimated the pollutant transport pathways over two years in the post-COVID-19 period (2023-2024). The methods employed were time-series analysis, scatter-plot evaluation, multiple linear regression analysis, and backward trajectory modeling using HYSPLIT. The results show that the average PM2.5 concentration in 2023 (30.53 µg/m³) was higher than in 2024 (25.36 µg/m³), with night-time levels generally exceeding day-time levels. 3.69% of the days exceeded Indonesia’s daily air quality standard, while 90.83% surpassed the stricter WHO guideline. Meteorological factors explained only 23–38% of PM2.5, with temperature positively correlated, wind speed showing mixed effects, and humidity and rainfall negatively correlated.. The major PM₂.₅ sources influenced by the southeast–South Sumatra, particularly South Sumatra, highlighting the strong stimulus of transboundary emissions alongside local sources. In the future, studies focusing on chemistry-based source apportionment are needed to accurately separate each contributing source.
Calcined Green Mussel Shell Waste as a Bioaggregate in Pervious Concrete Paver Blocks
Ineffective management of green mussel shell waste could worsen environmental problems. Green mussel shell waste can be used as bioaggregate, because it contains 90% CaCO3, the content is similar to limestone, which is generally chemically inert. Seashells calcined at high temperatures and fine particle size can show limited reactivity. The purpose of this study was to determine the amount of green mussel shell waste production and to determine the optimal proportion of calcined green mussel shell (GMS) bioaggregate in pervious concrete paver blocks (PCPB). The methods used were observational to calculate the amount of waste produced over 8 consecutive days and experimental to determine the mechanical and physical performance of pervious concrete paver blocks with bioaggregate substitution levels of 0%, 6%, 12%, 18%, and 24% at a test age of 28 days. The pervious concrete paver blocks were molded using an automatic hydraulic press machine that was vibrated for 10 seconds, with a mold size of 21 x 10.5 x 6 cm. The testing included the constituent materials and test specimens in accordance with the standards. Green mussel shell waste production during the 2025 planting season was 87.27 kg/day. The test results showed that the compressive strength, porosity, and permeability coefficient values were within the range recommended by ACI 522R-10 2010 and SNI 03-0691-1996 for permeable concrete used as pavement material.
Integrated Hydrological–Empirical Modeling for Lake Water Balance Estimation in a Data-Scarce Volcanic Catchment
Menjer Lake has undergone various human interventions, such as land use change and hydropower consumption, but has no water level monitoring data in its small catchment area of 2.7 km² and steep morphology. Thus, the objective of this study was to integrate a hydrological model with an empirical model to estimate the water balance of a lake in a data-scarce catchment. The results indicate that the runoff model for an ungauged river demonstrates the good performance of the hydrological model using the Soil and Water Assessment Tool (SWAT) based on its similarity to observed rainfall (R² = 0.93). However, the lake water balance is very complex because of multiple input and output sources. Moreover, land-use change had no significant impact on runoff, as no anomaly was found in the runoff model results. Under existing conditions, artificial inflow plays a significant role in the water balance input and output of Menjer Lake. The artificial inflow covered 76% of the water input, with an outflow of 12.3%, preventing any deficit phase. Overall, this study underscores the importance of considering manual calibration with rainfall data in data-scarce areas. The good correlation between rainfall-runoff shows that this model is also acceptable
Performance Study of Glassfibre Reinforced Concrete (GRC) with Ferric Oxide Waste Additive
Portland cement production is a major contributor to carbon emissions in the construction sector because the high-temperature calcination process produces CO₂ emissions that are nearly equivalent to the mass of cement produced. This study focuses on evaluating the potential of ferric oxide waste material in glass fiber-reinforced concrete as a filler to reduce carbon emissions, making it more environmentally friendly. An experimental method was used with a 1:1 binder-to-aggregate ratio and a constant 3% glass fiber addition. The percentage of ferric oxide replacement in the cement was 0–40%. X-ray fluorescence, X-ray diffraction, particle size distribution analysis, sand gradation testing, and mud content were used to obtain the material data. Tests were also conducted to determine compressive strength, flexural strength, water absorption, and dry and wet bulk density. Based on the results obtained, the addition of ferric oxide improved the mechanical properties of glass fiber-reinforced concrete and added to the aesthetic value of the final product. These findings indicate that the application of Glassfibre Reinforced Concrete is environmentally friendly
Analysis of Carbon Emission Mitigation Potential from Solid Waste Management at Campus Environment
Greenhouse gas emissions from waste management contribute to climate change, including in higher education institutions. This study aimed to evaluate the potential for carbon emission mitigation from waste management at the Politeknik Perkapalan Negeri Surabaya campus through organic waste composting and inorganic waste recycling using a waste bank system. The application of solid waste generation measurement was combined with the Intergovernmental Panel Climate Change guidelines and SNI 3964:2025. A descriptive quantitative approach was employed, utilizing primary data on solid waste characteristics from selected campus buildings. Baseline emission estimates and mitigation scenarios were used, assuming partial implementation of the 3R program: organic waste composting and recycling. The results indicate that the waste management sector produces approximately 5.44 tons of CO₂ per year, and the proposed emission reductions could reduce emissions by approximately 63%. The findings of this study indicate that integrated waste management has significant potential for reducing carbon emissions and supporting the development of low-carbon campuses aligned with Sustainable Development Goals 12 and 13, despite the methodological limitations related to the assumptions of emission factors and the level of implementation
Effects of Steam Pretreatment and Delignification Time on Balsa Wood Polyvinyl Alcohol Composites
The effect of controlled steam pretreatment on polyvinyl alcohol/balsa wood composites was investigated. Controlled steam was applied prior to subsequent sodium chlorite-acetic acid delignification of balsa wood and its impregnation with polyvinyl acetate (PVA). Low-density balsa veneers were either not subjected to steam or were steamed at 126 °C for 1 h. Wood delignification was carried out in a 1% solution of sodium chlorite-acetic acid at 80 °C for 45, 90, or 180 min. The samples were further bleached in a 3% hydrogen peroxide solution and vacuum-impregnated with 5% PVA. The Wood-PVA system was monitored using color, tensile, FTIR, and X-ray diffraction analyses. The steam-pretreated and delignified for 90 min sample (90S) exhibited the best characteristics, showing a tensile strength of 3.39 MPa and Young’s modulus of 112.36 MPa. The obtained data indicated continuous removal of lignin and hemicellulose, much stronger PVA-cellulose interactions, and preservation of cellulose in its native cellulose I state without a significant decrease in crystallinity. The proposed treatment represents a reproducible way to convert balsa wood into a stiff, formaldehyde-free, and low-density composite material available for implementation in modern building technologies.
Sustainability Analysis of Black Soldier Fly Cultivation in Mojokerto City using Multidimensional Scaling-Rapfish
Urban organic waste remains a major environmental challenge in developing cities worldwide. It constitutes the bulk of municipal waste streams, primarily the organic fraction, including household food waste and organic market scraps, and contributes significantly to greenhouse gas emissions. BSF larvae bioconversion offers a nature-based solution that can reduce organic waste while producing valuable biomass for circular bioresource systems. However, research that quantitatively evaluates the multidimensional sustainability of community-based BSF cultivation programs at the city level, particularly in Indonesia, is limited. This study evaluated the sustainability of the BSF cultivation program in Mojokerto City using MDS-RAPFISH, which encompasses five dimensions: environmental, economic, social, institutional, and technological. An indicator-based assessment utilizing conceptual modelling and policy analysis determined the program’s sustainability status and leverage attributes. The overall sustainability index was 54.22, which indicates moderate sustainability. The highest score was recorded in the environmental dimension (74.97). The subsequent dimensions were social (66.34), institutional (65.82), technological (61.70), and economic (60.92). These results show that there are constraints in terms of community participation, institutional support, technological consistency and market integration. The results show that although BSF cultivation has significant environmental benefits, it needs to be supported more technically and economically to be sustainable
Enhancing Stabilized Leachate Treatment with C. comosum, E. palaefolius, and E. hyemale in Constructed Wetlands
Stabilized landfill leachate is challenging to treat because of its high content of refractory organic matter and low biodegradability (BOD/COD ratio <0.16). This study investigated the performance of three ornamental plants, C. comosum, E. palaefolius, and E. hyemale, in laboratory-scale subsurface-flow constructed wetlands for treating stabilized leachate from the Ngipik Landfill, Gresik, Indonesia. The experiments were conducted under batch conditions with a hydraulic retention time (HRT) of 9 days. The treatment efficiency was evaluated based on the removal of BOD, COD, TSS, and TN. E. palaefolius achieved the highest COD and TSS removal efficiencies of 46.92% and 99.36%, respectively. The greatest COD reduction was observed in E. hyemale (63.30%), whereas C. comosum showed the highest TN removal efficiency (93.01%). Despite significant reductions in pollutants, only the TSS concentration in the treated effluents (2-12 mg/L) met the 100 mg/L discharge standard. BOD, COD, and TN levels remained above the regulatory limits. The results indicate that these ornamental plants are suitable for leachate pre-treatment, although longer retention times or additional treatment processes are required to achieve full compliance with environmental standards.
Performance Evaluation and Operational Optimization of a Fine-Bubble Porous–Venturi Aeration System
Aeration is the most energy-intensive unit in wastewater treatment systems, particularly in shallow decentralized reactors with limited hydrostatic pressure, which, which reduces oxygen transfer efficiency. However, systematic evaluations of integrated porous–Venturi microbubble systems under shallow-water conditions are limited. This study aims to address this gap by investigating and optimizing a fine-bubble porous–Venturi microbubble generator (MBG) using laboratory-scale experiments. Clean water experiments were conducted in a 200 L batch reactor with two liquid flow rates (71.6 and 103.8 L/min) and four gas flow rates (0.15–0.60 L/min). Aeration performance was assessed using the volumetric oxygen mass transfer coefficient (KLa(20)), standard oxygen transfer rate (SOTR), and specific aeration efficiency (SAE), supported by one-way ANOVA. The results showed that the gas flow rate influenced KLa(20) and SOT,R whereas the liquid flow rate had a dominant effect on SAE. The optimal operating conditions were identified as QL = 71.6 L/min and QG = 0.45 L/min, achieving KLa(20) of 2.23 h⁻¹ and SAE exceeding 40 kg O₂/kWh. The findings showed that optimum gas–liquid interaction leads to energy-efficient aeration performance rather than maximum flow rate supply. It also provides practical design insights for optimizing aeration systems in shallow and decentralized wastewater treatment applications
Linking Degree of Deacetylation to Coagulation Efficiency of Crustacean Waste Chitosan in Water Treatment
Turbidity removal remains challenging because stable colloids resist sedimentation, motivating the use of biodegradable coagulants such as chitosan derived from crustacean waste. However, an integrated quantitative linkage between the degree of deacetylation (DD), zeta potential evolution, and dose-dependent turbidity removal across pH is still limited for shell waste-derived chitosan. This study aimed to relate DD to the zeta potential behavior and coagulation efficiency of chitosan derived from green mussel, crab, and shrimp shells at pH 5, 7, and 9. At pH 7, shrimp-shell chitosan (DD 89.05%) achieved 98.38% turbidity removal at 190 mg/L, crab-shell chitosan (DD 87.64%) achieved 96.72% at 320 mg/L, and green mussel chitosan (DD 77.80%) achieved 95.08% at 300 mg/L [mean±SD, n=3]. The zeta potential shifted from −0.81 mV (untreated synthetic water) to +1.43 to +2.80 mV after dosing, indicating dominant charge neutralization with partial overcompensation. Overall, DD provides a practical screening descriptor for selecting locally sourced chitosan and optimizing the dose for sustainable turbidity control. Valorizing shell waste into effective coagulants may reduce the reliance on inorganic coagulants and support environmentally responsible water treatment practices. This study established an integrated DD zeta potential dose relationship across pH to explain and compare the coagulation performance of locally sourced shell-waste chitosan for turbidity removal.
Sustainable Pollutant Removal through Integrated Biological, Physical, Electrochemical Treatment: Resource Recovery and LCA Study
Vinasse from bioethanol distillation contains high levels of organic matter, suspended solids, color, sulfides, and acidity, requiring integrated treatment beyond biological methods. This study tested a sequential system comprising anaerobic digestion, aerobic oxidation, sedimentation, and electrochemical oxidation using a Ti/RuO2 anode and stainless-steel cathode at different NaCl concentrations. The system reduced pollutants in 10% diluted vinasse, lowering COD, BOD, and TSS by 97.9 %, 99%, and 93.6%, respectively, eliminating sulfide, and increasing pH to 8.2. The electrochemical step polished water by generating hydroxyl radicals and reactive chlorine species. Six grams per liter of NaCl provided optimal water quality, with high color removal, turbidity reduction, sulfide removal, and pH stabilization. The GWP of the four resource-recovery techniques was assessed in a life cycle study. Sludge and biogas recovery produced the least climatic impact, according to Monte Carlo statistical analysis, which revealed GWP emissions of 0.842–1.125 kg CO2 eq/kg treated water across four suggested scenarios with a ≤3% coefficient of variation and a tiny standard error of the mean. Overall, this system combines pollutant removal, water recovery, sludge valorization, and environmental impact assessment to provide an efficient circular method for vinasse treatment
Copyright 2026 Jurnal Presipitasi: Media Komunikasi dan Pengembangan Teknik Lingkungan http://creativecommons.org/licenses/by-nc-sa/4.0
Performance Test of Environmental Odour Measurement Instrument
Environmental odour assessment is important for evaluating air quality and community amenity; however, conventional dynamic dilution olfactometry requires specialised laboratory facilities and costly equipment, limiting its use for routine field monitoring. This study developed and evaluated a direct-airflow environmental odour measurement instrument that delivers ambient air directly to panellists without dilution. The instrument was designed to operate at an airflow velocity of 1 m/s, selected through climatological analysis, panellist preference testing, and technical verification against ASHRAE Standard 55 and EN 13725:2022. Eight screened panellists assessed ambient air, n-butanol, and ammonia using the Yuwono Hedonic Scale under field conditions. Instrument performance, panellist consistency, and the influence of meteorological conditions on odour perception were evaluated. The selected airflow velocity of 1 m/s yielded the highest ratings for odour detectability, comfort, and ease of assessment. Repeated ammonia measurements (3.4–3.5 ppm) produced highly consistent hedonic scores (−3.2 to −3.0), while ammonia concentration and hedonic scores followed a logarithmic relationship (R² = 0.9994). Mean hedonic scores for ambient air (−0.1), n-butanol (−1.3), and ammonia (−3.1) confirmed consistent panellist discrimination of odour characteristics.
Thermal Characterization and Heat Conductivity of Palm Kernel Shell-Based Briquettes
Palm kernel shell (PKS), a major by-product of the palm oil industry, has emerged as a promising sustainable feedstock for solid biofuel briquette production. This study presents a systematic review of PKS briquettes, emphasizing their thermal properties, briquetting technologies, pretreatment methods, environmental and economic impacts, and future prospects of PKS briquettes. A PRISMA-based methodology was applied to ensure the transparent identification, screening, and synthesis of relevant peer-reviewed studies on PKS briquette production and performance. The review indicates that PKS briquettes generally possess a high calorific value, substantial fixed carbon content, and competitive combustion performance compared with other biomass fuels. Advances in densification techniques and pretreatment processes have improved the fuel quality, durability, and energy efficiency. Despite these strengths, several research gaps remain. Standardized data on thermal conductivity and heat transfer are limited, and comparative assessments with conventional fuels, such as coal and firewood, are insufficient. Moreover, inconsistencies in the experimental conditions hinder cross-study evaluation, and emission characteristics and large-scale industrial feasibility are underreported. By consolidating current findings and identifying critical knowledge gaps, this review offers a structured foundation for future research and informed policymaking, supporting the integration of PKS briquettes into sustainable energy and circular economy strategies in palm oil–producing regions
Carbon Literacy in Higher Education: A Systematic Review of CO₂ Emission Education and Its Impact on Student Behavioral Change
Carbon literacy education has emerged as a key strategy for addressing climate change by enhancing environmental awareness and promoting pro-environmental behavior among university students. This study presents a systematic literature review examining how CO₂ emission education is conceptualized, implemented, and evaluated within higher education institutions and its influence on student behavioral change. This review synthesizes peer-reviewed studies published between 2015 and 2026, focusing on conceptual frameworks, pedagogical approaches, and behavioral outcomes. The findings indicate that carbon literacy education improves climate knowledge, strengthens environmental attitudes, and increases students’ intentions to adopt sustainable practices in the future. Pedagogical strategies, such as experiential learning, project-based learning, life cycle assessment, and campus-based sustainability initiatives, play a critical role in translating knowledge into actionable competencies. However, a persistent awareness–action gap remains, wherein increased knowledge does not consistently lead to sustained behavioral change. The effectiveness of educational interventions is strongly influenced by psychological engagement, social learning environments and institutional support. Overall, this study emphasizes the need for integrated and interdisciplinary approaches that combine cognitive, experiential, and institutional dimensions. Embedding carbon literacy across curricula and campus practices can enable higher-education institutions to foster meaningful behavioral change and contribute to climate-mitigation efforts.
Analysis of The Implementation of The ISO 14001:2015 Environmental Management System at Manufacture Industry
ISO 14001:2015 is an international standard issued by the International Organization for Standardization that regulates Environmental Management Systems (EMS) to help companies manage environmental impacts, comply with regulations, and achieve continuous improvement. Manufacture Industry, a foreign investment company engaged in diesel engine production, implements EMS as part of its commitment to environmental sustainability. This study evaluates the implementation of ISO 14001:2015 by comparing each clause of the standard with actual operational practices within the company. Data were collected through field observations and document reviews. The results show that Manufacture Industry has effectively implemented all clauses of ISO 14001:2015, particularly in waste management, air quality monitoring, and regulatory compliance. However, improvements are still needed in increasing employee awareness regarding the use of PPE in high-risk work areas. This study provides a more practical and structured approach to EMS evaluation by integrating clause-based ISO assessment with real industrial practices, which can serve as a reference for industries in improving EMS performance and operational control.
Copyright 2026 Budi Prasetyo Samadikun http://creativecommons.org/licenses/by-nc-sa/4.0
Environmental Valuation of Mobile MBBR Reactor for Wastewater Management in Non-Rural Area
Domestic waste remains a problem in Ngagel Rejo Village, Surabaya City, where the community is largely composed of small medium enterprises (SMEs) food traders. This study aims to assign an economic value to domestic waste management services that are not traded in the market. The benefits of deploying a mobile Moving Bed Biofilm Reactor (MBBR) will be estimated to determine the economic value of WWTP siting and to develop a retribution (user-fee) scheme for domestic waste management, particularly for the food waste consortium. A Contingent Valuation Method (CVM) will be used to elicit willingness to pay (WTP) from WWTP users as a measure of the non-use benefits of this public service and its role in reducing the impacts of domestic waste. The analysis yielded a mean WTP value of 3.6827 (as measured in the survey), which corresponds to a recommended fee of IDR 69,496.00 per month for domestic waste management services using a mobile MBBR reactor. Key factors influencing WTP include community commitment to environmental preservation programs and support for the program, consistent with the idea that public engagement strengthens the sustainability of environmental initiatives
Analysis of Solid Waste Generation, Composition, and Economic Potential Using Cost-Benefit Analysis Method
The Natar market is experiencing an increase in solid waste generation that has not been resolved optimally due to inadequate Temporary Waste Storage Site facilities and a lack of awareness, causing waste accumulation and the transfer of problems to the landfill. This study aimed to analyze solid waste generation and composition based on SNI 19-3964-1994 and to assess the economic potential of recycled waste and the cost-benefit analysis for organic waste processing. The amount of waste produced at the Natar Market was 884.45 kg per day and 7,902.33 liters per day. The composition of solid waste is dominated by organic waste (87.34 %), Low-Density Polyethylene plastic (8.70 %), paper/cardboard (2.14 %), Polyethylene Terephthalate plastic (1.27 %), and other types of waste less than 1%. The selected waste processing alternative was the Black Soldier Fly technology, with a scoring and weighting result of 418 points. Recycled waste has the potential to generate an economic value of IDR 2,151,796.50. The cost-benefit analysis shows that Black Soldier technology is feasible to implement with a Net Present Value of IDR 497,543,239.61, an Internal Rate of Return of 12%, and a Benefit Cost Ratio of 1.017.
Hair Mercury Concentrations among Residents Living Near Artisanal and Small-Scale Gold Mining Activities in Indonesia
Mercury use in artisanal and small-scale gold mining (ASGM) remains a major public health concern in Indonesia. This cross-sectional biomonitoring study examined the factors associated with mercury exposure among 50 adults living near ASGM activities in the Bungo District. The interview data covered sociodemographic, occupational, behavioral, and exposure-related factors, while hair mercury concentrations were measured using inductively coupled plasma mass spectrometry. Descriptive analyses, bivariate logistic screening, and multivariable logistic regression with backward stepwise selection were performed. In the final model, non-mining participants had lower odds of higher mercury exposure than mining-related workers (OR = 0.164; 95% CI: 0.030–0.892; P = 0.036). Adults aged ≥45 years had lower odds than those aged 21–44 years (OR = 0.097; 95% CI: 0.020–0.474; p = 0.004), whereas women had higher odds than men (OR = 8.032; 95% CI: 1.586–40.675; p = 0.012). The model showed moderate explanatory performance (Nagelkerke R² = 0.414) and 78.0% accuracy. These findings indicate higher exposure among younger adults, women, and mining-related workers, supporting targeted biomonitoring, occupational risk reduction, and community-based interventions in areas affected by ASGM.
Sustainable Management and Community Willingness to Pay for Communal Wastewater Services in Yogyakarta
Domestic wastewater discharge into rivers remains a persistent environmental and public health challenge in rapidly urbanizing regions of developing countries such as China. Although communal wastewater treatment systems have been increasingly implemented, empirical studies integrating community willingness to pay (WTP), behavioral determinants, and sustainability planning are limited. This study analyzes community willingness to pay for communal wastewater treatment services and formulates sustainability-oriented strategies for the Sewon Communal Wastewater Treatment Plant (WWTP) in the Special Region of Yogyakarta, Indonesia. A mixed-methods approach combined a survey of 100 households with interviews and a document analysis. WTP was estimated using the contingent valuation method with a payment card format, while behavioral determinants were examined using covariance-based Structural Equation Modelling (SEM) with AMOS. Strategic formulation was conducted using SWOT analysis supported by IFAS and EFAS matrices based on validated SEM results. The results indicate a positive willingness to pay, with a mean of IDR 7,114 and a median of IDR 7,500. The SEM revealed that supporting institutional factors significantly influenced the WTP (X4 = 0.664; p < 0.01), whereas environmental perception and inhibiting factors were not statistically significant. These findings highlight the decisive role of institutional strength in ensuring the financial sustainability of the communal wastewater service
Improving Low Carbon Development Performance at the Local Level through Multi Criteria Decision Analysis
Climate change necessitates immediate local interventions to guarantee environmental stability. Notwithstanding emission target agreements, Mojokerto Regency’s contribution to regional low-carbon development is less than 1%, indicating minimal influence. This study examines the enabling and constraining factors of low-carbon performance and establishes strategic priorities using the Analytical Hierarchy Process (AHP), corroborated through a Cost-Effectiveness Analysis (CEA). Data were gathered through expert interviews, pairwise questionnaires, and a regional fiscal analysis. The findings demonstrate that structural limitations, such as constrained resources and data deficiencies, impede implementation, whereas multi-stakeholder interaction serves as a key facilitator. AHP designated Community Engagement as the key choice criterion (31.32%). Thus, waste management using TPS3R was prioritized at 26.12%, followed by tree planting at 20.09% and organic fertilizer at 13.88%, together comprising 60.09% of choice preferences. CEA validates these findings, indicating that prioritized community-based methods provide enhanced fiscal efficiency, substantial landfill cost savings, and local job creation. They surpass capital-intensive alternatives, such as Intelligent Transportation Systems (ITS/ATCS), which provide minimal carbon value. This report advocates for the reallocation of municipal finance to prioritize community empowerment and nature-based initiatives, underpinned by institutional legislation that requires data sharing for Measurement, Reporting, and Verification (MRV) systems to facilitate an economically sound and socially equitable shift
Evaluating the Environmental Impacts of Thermoplastic Based-Product Manufacturing Using Life Cycle Assessment (CML-IA Midpoint)
The rapid growth of thermoplastic manufacturing in Indonesia, particularly in thermoplastic-based products such as children’s toys, has not been accompanied by sufficient environmental assessment, especially Life Cycle Assessment (LCA). While previous studies have mainly focused on extrusion processes, this study incorporated additional processes, such as spray coating, to provide a more representative evaluation. This study evaluated the environmental impacts of vacuum cleaner manufacturing using LCA with the CML-IA midpoint method. The data were processed using OpenLCA 2.4.1 and the ELCD database. The results indicate that producing one unit of a vacuum cleaner contributes to multiple environmental impact categories, including acidification (0.001 kg SO₂-eq), eutrophication (0.0001 kg PO₄³⁻-eq), Freshwater Aquatic Ecotoxicity (0.001 kg 1,4-DB eq), and Global Warming Potential (4.208 kg CO₂-eq). Additional impacts were identified in Human Toxicity (0.406 kg 1,4-DB eq), Marine Aquatic Ecotoxicity (2558.698 kg 1,4-DB eq), Photochemical Oxidation (0.000025 kg C₂H₄-eq), and Terrestrial Ecotoxicity (0.041 kg 1,4-DB eq). Among these, Marine Aquatic Ecotoxicity emerged as a dominant contributor because of the presence of hydrogen fluoride released into the environment during the spraying process. To address this issue, mitigation measures, such as substituting inorganic paints in the spray coating process with organic or ecolabel-certified alternatives, have been proposed
Flood Risk and Economic Loss Assessment in the Lower Citarum Basin Using InaSAFE
The hydrometeorological hazard of flooding in the Lower Citarum River Basin constantly affects agricultural sustainability, infrastructure, settlements, and regional economic activities. This study used InaSAFE to model human exposure and economic losses due to flooding under a 50-year return-period scenario. Flood depths were classified as >1.5 m (high), 0.76–1.5 m (medium), and ≤0.76 m (low) and then overlaid with spatial layers of population, land cover, roads, and buildings. The results revealed 1,739,195 exposed individuals, with 1,067,442 requiring evacuation support from medium-to high-depth classes. The different types of land cover exposed to floods cover 126,413 ha, mainly agricultural areas. The minimum humanitarian relief needs are US$ 88.00 million. The losses from buildings and public facilities totaled USD 616.51 million, and for road infrastructure, they amounted to USD 1.23 million, providing a subtotal of primary direct losses of USD 894.67 million. Additional proxy-based elements raised the stretched notional economic-loss estimate to USD 2.64 billion. These results offer a baseline for additional studies on flood-risk reduction and future scenario-based analyses of possible mitigation alternatives; they are not an explicit evaluation of the hydraulic or economic effectiveness of the Cijurey Dam.
Planning Sludge Bioconversion Using Black Soldier Fly Larvae in Tofu Production Centers
Sugihmanik Village, Tanggungharjo District, Grobogan Province, is a major tofu-producing area affiliated with 20 MSMEs and the Waste Transportation Authority (PLTA). Although tofu contributes to the local economy, poor wastewater management from fish farming installations can cause environmental issues. The objective of this study was to develop an environmentally friendly and sustainable wastewater management system based on black solid fuel (BSF). The research methodology included water consumption levels and quality, steam generation, and the development of a BSF bioconversion system. The test results showed that the hydroelectric power plant produced 694.21 kg/day (0.68 m3/day) from the wastewater treatment process. The proposed model utilizes the transition of wastewater and the wastewater environment in the BSF ecosystem. This process produces valuable products, including soft BSF larvae as a protein source and BSF waste as raw material