Environment and Natural Resources Journal

Effects of Biochar Amendment on CO2 Evolution in Four Ecotypes of Leyte Sab-A Basin Peatland, Philippines

Pearl Aphrodite Bobon-Carnice — 2025-01-31

Atmospheric carbon cycle criticisms are significant liabilities in existing predictions of future climate. Carbon dioxide (CO₂) discharges caused by climate warming through dense peat stores will frame a stable positive carbon cycle–atmospheric input. An experimental-descriptive analytical method was used to acquire data on quantifying the amount of CO₂ evolved in the four adjacent ecotypes of Leyte Sab-A Basin Peatland (LSBP), Philippines, both with and without biochar incorporation. Results showed that after 120 days of incubation, the CO₂ evolved between ecotypes measured 0.73 mg CO₂/g, 0.31 mg CO₂/g, 0.23 mg CO₂/g, and 0.20 mg CO₂/g for TML (marshland), TPF (peat forest), TAL (agricultural land), and TMV (mixed vegetation), respectively. In comparison, treatments with biochar were 0.81 mg CO₂/g, 0.57 mg CO₂/g, 0.46 mg CO₂/g, and 0.43 mg CO₂/g for TMLB (marshland+biochar), TPFB, TMVB, and TALB, respectively. Results rendered significant differences between ecotypes, and between those with added biochar (p-value: 1.8E-06). This study concludes that TML with and without biochar had the highest evolved CO₂ over time, implying the best ecosystem preservation among the ecotypes. For future studies, these findings establish a scientific basis for adaptive response assessment of peatlands to climate change, and for decisions made in support of policy changes.

Nexus between Livelihood Strategies and Food Security Status in Landslide-prone Areas of the Gammo Highlands, South Ethiopia: A Quantitative Analysis

Lemma Tadesse — 2025-02-27

Investigating the relationship between various livelihood strategies and food security status is crucial to understanding how different economic activities impact access to food security. This study explores the relationship between multiple livelihood strategies and the food security status among rural households vulnerable to landslide hazards in the Gacho Baba District of the Gammo Highlands South Ethiopia. Data were collected from 289 statistically selected sample households in the district employing multistage sampling techniques. Questionnaires assessed the demographic, socioeconomic, and food security-related data. Meanwhile, livelihood strategies were categorized based on on-farm, off-farm, and non-farm activities. Food security status was assessed using the Household Food Insecurity Access Scale (HFIAS), Food Consumption Score (FCS), and Reduced Coping Strategies Index (RCSI). Pearson correlation and one-way Multivariate Analysis of Variance (MANOVA) were inferential statistical tools used for data analysis. The Pearson correlation analysis revealed significant negative associations between livelihood strategies and food insecurity indicators. This suggests that diversifying livelihood activities is the best way to lower levels of food insecurity. Furthermore, the MANOVA results underscored the substantial impact of livelihood strategies on food security outcomes, underscoring the pivotal role of livelihood diversification in bolstering food security. Post hoc comparisons underscored the benefits of combining on-farm, off-farm, and non-farm activities for improved food security outcomes. The findings emphasize the need for targeted interventions promoting livelihood diversification to mitigate food insecurity risks among vulnerable rural households. Further research is warranted to explore underlying mechanisms and develop tailored strategies addressing multifaceted challenges in accessing nutritious food.

Development of Sustainable Packaging Cushions from Coconut Waste Using 3D Printing Techniques

Pongsak Kitirojapn — 2025-02-17

Coconut fiber and coconut coir dust can be used to create environmentally friendly packaging. Additionally, recycled corrugated paper can be combined with tapioca starch to bind coconut coir dust and paper. Using these techniques, our objective was to develop a novel process for producing different items with coconut pulp paper and 3D-printed molds. The results indicated that the optimal weight ratios of paper, coconut fiber, and coconut coir dust for a bottle, corner cushion and wrapping cushions were 60:20:20, 60:20:20, and 80:20:0, respectively. The 3D-printed molds were designed with rounded chamfers to facilitate easy extraction of the molded paper. Both the bottle and corner cushions exhibited a tensile strength of 0.53 MPa with 12% NaOH treatment. The wrapping cushion demonstrated the highest flexural strength, at 10.33 MPa with 12% NaOH. Overall, NaOH treatment improved the mechanical properties of the coconut fiber compared to untreated fiber. For compression, the bottle and corner cushions achieved values of 3,196.38 N and 1,550.68 N, respectively. Furthermore, both the bottle and wrapping cushions passed the drop test from a height of 150 centimeters. In Thailand, the coconut industry reports revenues of approximately 4.66 billion THB in 2023 and produces 337 million metric tons of waste. This research demonstrates the great potential of coconut by-products, and the utilization of waste valued at 647 million THB. Future studies could explore innovative mold designs to enable the production of more complex packaging and decorative items, further enhancing the economic and environmental benefits of coconut waste utilization.

Numerical Investigation of Hydraulic Performance in Makhool Spillway Dam

Fatima A. Sadiq — 2025-02-27

Dams are critical hydraulic structures, and analyzing their hydraulic properties is essential for ensuring their functionality. While experimental tests have traditionally been used to evaluate the performance of dams, but now (CFD) software, such as among this the Flow 3D, now offers a reliable alternative or complement to physical models, ensuring accuracy while reducing time and effort. This study investigates Makhools’ Spillway Dam in Iraq, one of the country’s most significant hydraulic projects. A 3D numerical model of the dam was developed to assess its operation and performance. Its properties were analyzed and validated by comparing the results with physical model data, focusing on key hydraulic parameters such as velocity and water flow depth. The velocity results closely align with the physical model data, with only a minor variation in flow depth, which remains within an acceptable range. The RMSE value for velocity was below 5%, while the difference in the flow depth was approximately 3.63%, indicating a strong correlation between the numerical and physical models. These findings confirm that advanced numerical modeling techniques can effectively complement or serve as a reliable alternative to real-world studies.

Using Recycled Coal Ash from Thermal Power Plants and Rice Husk Ash as Alternative Aggregates for the Manufacturing of Terrazzo Tiles

Nguyen Thi Minh Trang — 2025-02-24

This study investigated the technical specifications of Terrazzo tiles manufactured using coal ash from thermal power plants and rice husk ash (RHA) to partially replace sand and cement as primary aggregates. Sample bricks with different mixed ratios of fly ash, bottom ash (slag), and RHA were produced with a hydrostatic-press machine with a standard mode of 400×400×30 mm. Our results showed that the brick density, flexural strength, and water absorption were significantly affected by the variation of fly ash and RHA content. The optimum ratio by weight of aggregate ingredients was found to be fly ash of 10%wt., RHA of 30%wt., and slag of 5%wt., accompanied by crushed stone at 55%wt. This produced brick products comparable to Terrazzo tiles, type 2, Mac 4.0. This classification satisfies the Vietnamese national standard for exterior bricks, and also is competitive with commercial quality in the local market. The reuse and recycling of waste from thermal power plants and RHA for manufacturing new construction material was thus demonstrated successfully in this study. This helps to emphasize the trend of net zero emissions, and further encourages the concept of reutilization towards sustainable development.

Performance and Heavy Metal Leaching Behavior of Bituminous Fly Ash-Based Geopolymer in Aggressive Environments

Parichat Muensita — 2025-02-28

This article investigates the performance of a geopolymer synthesized from bituminous fly ash (BFA) activated with sodium hydroxide. The BFA-based geopolymer (BFAG) exhibited high mechanical strength and a densified microstructure. The optimal SiO₂/Al₂O₃ and Na₂O/SiO₂ molar ratios were found to be 3:1 and 0.2, respectively, yielding a 28-day compressive strength of 9.65 MPa. The inclusion of 30wt.% of a PS material containing heavy metals led to a substantial reduction in strength by 56% and 73% compared to samples with the SiO₂/Al₂O₃ molar ratio of 2:1 and 3:1, respectively, at 28 days. The ability of the BFAG matrix to contain 30wt.% PS was evaluated using a waste extraction test (WET). The leaching behavior of heavy metals from the BFAG matrix was assessed with three aggressive leachants: sodium citrate, sodium acetate, and synthetic acid rain. Results showed that, under exposure to these leachants, the leached concentrations of Cr, Fe, and Zn from samples with the SiO₂/Al₂O₃ ratio of 3:1 were lower than those from samples with the 2:1 ratio, with concentrations ranging from 0.32-1.73, 3.07-6.67, and 152-284 mg/L, respectively. Despite exposure to harsh conditions, the BFAG matrix effectively immobilized over 99% for Cr and Fe and Zn, except when exposed to sodium citrate which only retained 98.5% of Zn. BFAG can be used to treat heavy metal and heavy metal-contaminated sludge. This matrix reduces environmental exposure, thereby decreasing heavy metal leaching into the environment before safe disposal in landfills. BFAG can also be used as a cement substitute in the solidified process, which lowers treatment costs and reduces cement consumption. It can decrease carbon dioxide emissions from cement production.

Fiber Morphology of Syzygium tripinnatum (Blanco) Merr. Stemwood and Branchwood and Their Derived Values

Jayric F. Villareal — 2025-02-21

Syzygium tripinnatum (Blanco) Merr. is an indigenous fruit tree species in the Philippines. This study characterizes the fiber morphology (fiber length, diameter, lumen diameter, and cell wall thickness) and derived values (Runkel ratio, slenderness ratio, flexibility ratio, Mulhsteph ratio, and rigidity coefficient) of S. tripinnatum wood grown in the Philippines. The results revealed that branchwood fibers were 1.610% longer, and both fiber and lumen diameters were 2.170% and 9.600% thicker, respectively, compared to stemwood. However, the cell wall thickness of stemwood was 1.670% greater than that of branchwood. In terms of derived values, stemwood exhibited higher values by 10.410% for the Runkel ratio, 0.580% for the slenderness ratio, 1.990% for the Mulhsteph ratio, and 3.030% for the rigidity ratio, while branchwood displayed a 7.350% higher flexibility ratio. Statistical analysis indicated no significant difference in fiber morphology or derived values between the two wood types. Based on the fiber morphology, S. tripinnatum wood is highly rigid and stiff, making it difficult to collapse, and thus less efficient for pulp and paper production, and bulkier for paper. However, the study suggests that S. tripinnatum could be suitable for construction, furniture, tool handles, cabinetry and pilings due to its cell wall thickness, Runkel ratio, flexibility ratio, Mulhsteph ratio, and rigidity coefficient. Further research into other properties of S. tripinnatum wood, considering factors such as tree maturity, height, sample size, and habitat would be crucial for accurately determining its suitability for the intended applications.

Microplastic Pollution in an Urban Wastewater Treatment Plant: Unravelling Problems and Proposing Solutions

Anh Tuan Ta — 2025-02-10

Microplastics (MPs) are detected ubiquitously in aquatic environments worldwide, with wastewater treatment plants (WWTPs) serving as significant pathways for their entry. This study investigates MP removal efficiency and suggests improvements in a conventional municipal WWTP in Bangkok, Thailand. Wastewater samples were collected using a volume-reduced method and filtered into three size ranges (0.05-0.5, 0.5-1.0, and 1.0-5.0 mm). Particles bigger than 0.5 mm were assessed for abundance using an optical microscope and identified for polymer types using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, while smaller particles were analyzed using fluorescence microscopy and micro-FTIR. The average concentration of MPs entering the WWTP was 16.55±9.92 MPs/L, whereas the concentration discharged into the environment was 3.52±1.43 MPs/L. The resultant MP removal efficiency of the Bangkok WWTP stands at approximately 78%, a figure lower than that of WWTPs in developed countries. This discrepancy is attributed to the absence of a primary clarifier within the Bangkok WWTP and an under-designed grit channel. Thus, the implementation of a filter system using activated carbon is suggested. Based on the calculations, 21 filter units are required for the Bangkok WWTP to improve MPs’ removal effectiveness. This study provides vital data on the presence of MPs in a Bangkok WWTP, emphasizing challenges that impede effective removal efficiency. Additionally, this study proposes potential solutions to enhance the removal of MPs and address these issues.