Environment and Natural Resources Journal

Preliminary Assessment of Morphology and Elemental Composition of Fine Particulates in Selected Urban Areas of Java Island

2024-05-09T15:23:55+07:00

Rapid urbanization and high population density in three major cities in Indonesia, Bandung, Jakarta, and Tangerang have led to significant air quality issues. Fine inhalable particles (PM_2.5) with distinct morphologies and elemental compositions pose considerable health risks. This study evaluates the morphology and chemical composition of PM_2.5 in these urban areas on Java Island. PM_2.5 samples were collected for 24-hour periods using a Teflon filter with the Super Speciation-Air Sampling System (SuperSASS) following the EPA sampling schedule, from May to September 2022. The Teflon sample with the highest PM_2.5 concentration, representative of both weekdays and weekends, was selected for morphological analysis using Scanning Electron Microscopy-Energy Dispersive X-ray (SEM-EDX) and elemental characterization using Energy-Dispersive X-ray Fluorescence (ED-XRF) Epsilon. SEM images revealed distinct morphological characteristics at each site. In Bandung, particles were irregularly shaped, agglomerated, and flaky, with sizes ranging from 1.1-1.6 µm on weekdays and 0.9-1.3 µm on weekends. Jakarta has particles with semi-crystalline, tabular, elongated, and puff-like morphology, with sizes predominantly from 0.5-0.8 µm on weekdays and 0.9-1.3 µm weekends. In Tangerang, particles were irregularly faceted and agglomerated, with sizes between 0.5-1.3 µm on weekdays and 0.9-1.4 µm on weekends. Teflon-derived minerals (C,F) were present across all sites. EDX spectra revealed Ca-rich particles in Bandung, while S-rich particles were observed in Jakarta and Tangerang. XRF analysis further proved the major and minor elements, reflecting local pollution sources. The combined use of SEM-EDX and XRF offers a comprehensive profile of PM_2.5, highlighting specific pollution sources in each city.

A Two-Stage Feature Selection Method to Enhance Prediction of Daily PM2.5 Concentration Air Pollution

2024-07-25T15:39:00+07:00

In recent decades, air pollution has negatively affected human health and the environment. One of the important features contributing to air pollution is called PM_2.5. However, daily prediction of PM_2.5is still lacking, especially using feature selection infused into the model. Hence, the main objective of this research is to utilize the feature selection procedures by proposing two stages feature selection methods namely adjusted correlation sharing t-test (adjcorT) and radial basis function neural network (RBFNN) in identifying the important features. This consequently also helps enhance the prediction of daily PM_2.5concentrations. Secondary data were obtained from the Department of Environment Malaysia (DOE) from 2018 until 2022 that consists of 5 years of air pollutant daily data. The results found that adjcorT-RBFNN identified the NO₂, PM_2.5, PM₁₀, CO, O₃, wind speed and SO₂ as important features. The finding revealed that the accuracy, sensitivity, specificity, precision, F1 score and AUROC value, for a day-ahead prediction in Shah Alam are 0.756, 0.801, 0.717, 0.717, 0.757, and 0.758 respectively. Additionally, the predicted model may serve as an instrument for an early warning system, providing local authorities with information on air quality for formulation of strategies of air quality improvement.

Antioxidant Activity and Suppression of Intracellular Radical Generation of Streptomyces Strains and Genome Analysis of Strain ET3-23

2024-07-03T11:02:46+07:00

Actinomycetes, predominantly found in soil, represent a remarkable source of natural products. The natural antioxidants obtained from them have been employed for human infectious diseases. In particular, Streptomyces strains serve as significant sources of natural antioxidants with demonstrated health benefits. The in vitro antioxidant activity and the inhibition of intracellular radical generation by crude extracts from various Streptomyces strains were evaluated and the genome sequence of selected strains was analyzed. Strains CT2-10, NE1-12, and ET3-23 showed 16S rRNA gene sequence similarity to Streptomyces capoamus JCM 4734^T (98.94%), Streptomyces nigra 452^T (99.78%), and Streptomyces morookaense LMG 20074^T (99.49%), respectively. The genome analysis of strain ET3-23 had 106 contigs, with a total length of 8121874 bp and an average G+C content of 71.46%. Ethyl acetate extracts of strains CT2-10, ET3-23, and NE1-12 exhibited, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity with IC₅₀ 555.9 µg/mL, 66.5 µg/mL, and 463.3 µg/mL and showed NO scavenging activity, except for CT2-10. Strain NE1-12 significantly inhibited ROS production induced by hydrogen peroxide on macrophage cells, while strains NE1-12 and CT2-10 inhibited NO production induced by lipopolysaccharides with IC₅₀ 82.4 µg/mL and 2.3 µg/mL, respectively. These findings suggest their ability to modulate NO production which is crucial in inflammatory responses and tissue injury. The antioxidant activities of Streptomyces strains indicate their potential as valuable sources of bioactive natural products and effective antioxidant agents, warranting further investigation for therapeutic applications.

Utilization of High-Salinity Crude Glycerol Byproduct from Biodiesel Production for Biosynthesis of γ-Aminobutyric Acid in Engineered Halomonas elongata

2024-05-28T16:35:22+07:00

As the development of renewable energy has become imperative, biodiesel fuel (BDF) has been used as renewable biofuel with the advantage of having lower levels of greenhouse gas emissions. However, the transesterification reaction that produces BDF generates a high-salinity crude glycerol (CG) byproduct, which is difficult to recycle. Halomonas elongata is a moderately halophilic bacterium being used as a cell factory due to its ability to assimilate varieties of substrates for growth in high-salinity conditions. Previously, we engineered a recombinant H. elongata GOP-Gad to biosynthesize and accumulate γ-aminobutyric acid (GABA) as a high-value product. Here, we tested the ability of H. elongata GOP-Gad to use CG as a substrate for cell growth and GABA production. The CG byproduct was obtained from a BDF facility in Unzen City, Nagasaki, Japan, where geothermal energy catalyzed BDF production from waste cooking oil and biomethanol. Prior to use as the sole carbon (C) source in culture media, the CG byproduct was partially purified to remove soap substances and other impurities. Finally, we showed that H. elongata GOP-Gad could grow and accumulate GABA up to 28 μmol/g cell fresh weight in a minimal M63 medium containing 7% w/v NaCl with 4% w/v glycerol from the partially purified CG as a C source and 15 mM (NH₄)₂SO₄ as a nitrogen (N) source. This result demonstrates a new circulatory bioprocess of C and N, in which H. elongata GOP-Gad can use partially purified CG and (NH₄)₂SO₄ as the sole C and N sources for growth and GABA production.

Perceived Impacts of Climate Change on Coastal Aquaculture in the Cyclone Prone Southwest Region of Bangladesh

2024-05-16T11:33:23+07:00

The southwest region of Bangladesh is particularly vulnerable to a range of climatic threats, including cyclones, prolonged flooding, sea level rise, saltwater intrusion, drought, and riverbank erosion. The study investigates how these different drivers affect aquaculture systems and aims to provide critical insights for sustainable management. The survey work focused on the problems, vulnerabilities, migration, and adaptive strategies of communities of the southwest region of Bangladesh, that rely heavily on shrimp, fish, and crab production for their livelihoods. Data were collected from the 80 respondents across four unions (Atulia, Burigoalini, Gabura, and Bhurulia) in Shyannagar Upazila, Satkhira District, using a structured questionnaire survey and focus group discussions. Findings reveal that climate change events have significantly changed shrimp farming in enclosures, pond aquaculture, and crab point management, and negatively impacted livelihoods. Pond aquaculture appeared to be the most vulnerable to climate change conditions, followed by shrimp farming in enclosures and crab points. Furthermore, the adverse effects of climate change compelled human migration within the study area, primarily driven by the search for employment. This study provides evidence of the effects of various climate change stressors on shrimp, fish, and crab production systems and the adaptive difficulties of the communities dependent on aquatic ecosystems. As the natural calamity like cyclone cannot be prevented, understanding the impact of previous events may help people of the affected area as well as the policy makers to plan for better survival.

Waste Analysis and Characterization Study in a Philippine Science and Technology Research and Development Institution

2024-08-08T22:43:24+07:00

This paper presents the conduct of Waste Analysis and Characterization Study (WACS) in the Industrial Technology Development Institute of the Department of Science and Technology (DOST-ITDI) in Taguig City, Philippines. The study was produced following the introduction of 2020 guidelines developed by the Japan International Cooperation Agency for the Philippines to determine waste generation and generation rate per source, as well as waste composition, per capita generation, and bulk densities of the generated wastes. This then provided fundamental data in the formulation of initial plans and programs for the proper management of solid wastes in the institution. From the gathered results, DOST-ITDI generates 91.56 kg/day of solid waste during the dry season, and 77.54 kg/day during the wet season. The generated waste is composed of residuals for disposal (35.93% and 37.75%, dry and wet season), biodegradables (27.80% and 21.46%), and recyclables (22.54% and 28.95%). Per capita generation rates of 0.21 kg/capita/day (dry season) and 0.18 kg/capita/day (wet season) were also recorded. The research and development cluster of divisions was determined as a major contributor of waste at 42.37 to 57.62 kg/day. Bulk density values varied between waste fractions, with the main residuals for disposal components being the bulkiest at 29.27 to 32.90 kg/m³. The data collected from the study provided significant information useful in efforts to initiate programs for diversion of biodegradables, recyclables, and residuals-with further potential for recycling wastes, reducing residuals for disposal through proper segregation and recovery, and determining gaps and opportunities in plans, policies, and programs to improve solid waste management of the institution.

Efficient Recycling of Domestic Cooked Food Waste into Hermicompost Using Black Soldier Fly Larvae

2024-07-25T15:35:08+07:00

Economic progress, urban expansion, and enhanced quality of life in India have led to the formation of densely populated megacities and a significant increase in municipal solid waste generation. Such waste consists of a substantial volume of residues from food waste, kitchen waste originating from residential complexes, restaurants, and remnants of agricultural activities. Consequently, handling municipal solid waste has become a critical issue. Though composting is being practiced as an eco-friendly means of recycling organic waste, it is laborious and time-consuming. In the recent past, researchers have suggested the use of black soldier fly larvae (BSFL) as an effective solution for solid waste management. This study aims to assess the degradation potential of BSFL, which is gaining attention in recycling technology due to its composting capabilities, and its ability to produce soil amendments suitable for agricultural purposes. To evaluate the ability of BSFL to degrade different types of organic wastes, with a focus on cooked food waste, the compost formed after 14 days of degradation was analyzed based on elemental composition and other parameters. Comparative examinations were made with different vermicompost samples and hermicompost produced using BSFL to check the effect on plant growth. The analysis showed a higher percentage of nitrogen (4.21%), and phosphorus (0.5%) in hermicompost. The C:N ratio was 12:1 which is suitable for agronomical purposes. This study concludes that, BSFL are useful as versatile bioconversion agents of cooked food waste and provide a promising organic recycling strategy for sustainable waste management.

Carbon Sequestration Assessment Using Satellite Data and GIS at Chiang Mai Rajabhat University

2024-07-26T17:17:16+07:00

This study conducted a project to assess carbon sequestration in the forest area of Chiang Mai Rajabhat University, Mae Rim Campus, covering a total area of approximately 5,600 rai, with about 75% consisting of dry dipterocarp forest. The Sentinel-2 satellite data from 2019 to 2023 were used to analyze and classify forest density using the Normalized Difference Vegetation Index (NDVI). It was classified into four NDVI levels: highest, high, moderate, and low. Then, eight sample plots were distributed across all density levels to collect field data on tree species, number of trees, height, and diameter. The biomass and carbon sequestration in the sample plots showed a strong correlation with vegetation density, with the highest average correlation in February, particularly on February 13, 2023, showing the highest correlation coefficient of 0.817. This relationship is described by the equation y=78.601x‒25.726, indicating that this model is effective for estimating carbon sequestration. The analysis revealed that the area with the highest NDVI level of dry dipterocarp forest had the highest above-ground carbon sequestration rate of 16.25 tons per rai, whereas the forest with the lowest NDVI level had an above-ground carbon sequestration rate of 0.21 tons per rai. In total, the above-ground carbon sequestration for the trees amounted to 50,907.35 tons. This preliminary assessment serves as a promising foundation for future efforts the conservation and restoration of the university’s forest area, contributing to sustainable strategies for mitigating global warming.