Tạp chí Khoa học Tài nguyên và Môi trường

Research on the changes in the Phytoplankton community and Cyanobacterial toxin content in Hoa Binh reservoir

Mon, 07 Jul 2025 09:40:13 +0700

This study investigates the dynamics of the Phytoplankton community and the occurrence of Microcystin toxins in Hoa Binh reservoir from June 2023 to May 2024. A total of 44 Phytoplankton genera were identified, belonging to five phyla: Chlorophyta (50 %), Bacillariophyta (26 %), Cyanophyta (17 %), Dinophyta (5 %), and Euglenophyta (2 %). Among them, Chlorophyta and Dinophyta exhibited seasonal dominance, with Dinophyta thriving during the rainy season, while Chlorophyta prevailed in the dry season. Cyanobacteria exhibited low biomass, with four genera (Microcystis, Oscillatoria, Anabaena, and Pseudanabaena) identified as potential Microcystin producers, among which Microcystis accounted for 87.6 % of the total Cyanobacterial biomass. Microcystin concentrations ranged from 0.11 to 0.86 µg/L, below the WHO safety guideline of 1 µg/L, but still indicating a potential risk for domestic water use. Principal Component Analysis (PCA) and Pearson correlation analysis revealed no significant relationship between Microcystis biomass and Microcystin concentrations, suggesting the possible presence of non-toxic Microcystis strains or contributions from other Microcystin-producing taxa. Environmental factors, such as high pH, warm water temperatures, and high turbidity, were found to support the growth of Cyanobacteria, particularly Microcystis. No clear correlation was observed between Microcystis biomass or Microcystin concentrations and nutrient variables (nitrogen and phosphorus). These findings offer crucial insights into Phytoplankton succession and Microcystin-related risks in Hoa Binh reservoir, thereby informing water quality monitoring and management strategies.

Assessing the impact of climate change on the water resources in the Kon - Ha Thanh river basin, Binh Dinh province

Vũ Văn Ngọc, Vũ Duy Hưng, Nguyễn Thị Thùy Linh, Nguyễn Duy Thành Công — Mon, 07 Jul 2025 09:41:12 +0700

Climate change and its impacts on water resources are urgent issues that are receiving significant attention. The assessment of climate change's impact on the water resources of the Kon - Ha Thanh river basin was conducted using the MIKE NAM hydrological model, combined with two climate change scenarios, RCP 4.5 and RCP 8.5, published by the Ministry of Natural Resources and Environment in 2020. The model parameters were developed based on a data series from 1985 to 2022, to calculate annual flow, flood season flow, and dry season flow under the influence of climate change. Specifically, the parameters were calculated for three periods in the 21^st century: Early (2016 - 2035), mid (2046 - 2065), and late (2080 - 2099). The accuracy of the MIKE NAM hydrological model was demonstrated to be good, with a NASH coefficient achieving a high score above 0.8 after calibration and validation. The study results indicate that climate change in the area significantly impacts water resources, as evidenced by the uneven distribution of annual flow (+4 %), flood season flow (+6 %), and dry season flow (-3 %) under both RCP 4.5 and RCP 8.5 scenarios. This research can provide a foundation to support the management, exploitation, use, and sustainable development of water resources in the Kon - Ha Thanh river basin in the future.

Geographic Information System solution model for aquaculture in the Tu Ky district, Hai Duong province

Lê Vũ Hồng Hải, Nguyễn Sách Thành, Nguyễn Quý Đạt, Đào Khánh Hoài, Lê Đức Lộc — Mon, 07 Jul 2025 09:42:06 +0700

Geographic Information Systems (GIS) have become a crucial tool in the management and planning of aquaculture, enabling environmental monitoring, optimizing farming areas, and supporting decision-making based on spatial data. The GIS-based aquaculture management system in Tu Ky district, Hai Duong province is developed on WebGIS and Mobile GIS platforms, facilitating the collection, storage, analysis, and visualization of aquaculture data in both spatial and temporal dimensions. The system provides key functionalities for managing aquaculture areas, including information display, statistical data visualization in charts, and spatial analysis. The research findings demonstrate that the application of GIS not only enhances information connectivity between management agencies, enterprises, and farmers but also lays the foundation for sustainable aquaculture development and adaptation to climate change.

Phytoplankton biodiversity and the application in water quality assessment in Phai Loan lake, Lang Son city

Hồ Hạnh Linh, Lê Thu Hà — Mon, 07 Jul 2025 09:42:59 +0700

Phai Loan lake is located in the center of Lang Son city. Qualitative and quantitative samples of phytoplankton from Phai Loan lake were collected at six research points with 2 sampling periods in May and October 2024. Results of phytoplankton identification showed that 53 species and subspecies of phytoplankton were recorded, belonging to 17 families, 8 orders of 4 phyla. There are 27 species of Bacillariophyta, 13 species of Chlorophyta, 6 species of Euglenophyta, and Cyanobacteriophyta has 7 species. Phytoplankton density ranges from 5128 to 6260 cells/liter. Bacillariophyta had the largest density of species. Euglenophyta had the smallest algae density. The Palmer index, Euglenophyta index, and D index show that Phai Loan lake is moderately polluted.

Greenhouse gas inventory at Optrontec Vina Co., Ltd., located in Ba Thien II industrial park, Binh Xuyen district, Vĩnh Phúc province

Lê Thu Thủy, Lưu Thành Trung, Nguyễn Thị Minh Nguyệt — Mon, 07 Jul 2025 09:43:52 +0700

In the context of increasingly complex climate change, conducting Greenhouse gas (GHG) inventories for businesses has become crucial. This is not only a legal obligation but also an essential step for enterprises to accurately assess the environmental impacts of their production activities. Moreover, GHG inventories help businesses comply with environmental regulations, enhance their reputation and brand image, and seize opportunities in the rapidly growing carbon credit market. A study conducted at Optrontec Vina Co., Ltd., located in Ba Thien II Industrial Park, Binh Xuyen district, Vĩnh Phúc province, aimed to inventory GHG emissions and propose emission reduction solutions in compliance with Decree 06/2022/ND-CP regulates greenhouse gas emission mitigation and ozone layer protection. Through the inventory process, the company identified the main emission sources, including electricity consumption, fuel combustion, the use of refrigerant gases, and fire extinguishers, with electricity consumption being the largest source of emissions. Consequently, the study has inventoried emissions from fuel combustion, from using refrigerant gas, from firefighting equipment, from grid electricity, and reduction solutions such as transitioning to renewable energy with solar power systems and planting more trees. These solutions are not only an inevitable trend but also an opportunity for businesses to achieve sustainable and prosperous growth in today's context. The study demonstrates that conducting GHG inventories and proposing emission reduction measures are not merely responsibilities but also opportunities for businesses to develop sustainably, enhance competitiveness, and contribute to global efforts to address climate change.

Assessing land use change in Ninh Binh province using a landscape approach

Trịnh Thị Hoài Thu, Phạm Thị Làn, Nguyễn Hoàng Kiệt, Bùi Thị Hồng Thắm — Mon, 07 Jul 2025 09:44:48 +0700

This study assesses land use changes in Ninh Bình Province from 2015 to 2020 using a landscape approach, integrating Landsat remote sensing imagery and GIS analysis. The Random Forest algorithm on Google Earth Engine was applied for image classification, land use change detection, and landscape structure analysis over time. The results indicate significant transitions among land use types. Residential and built-up land experienced the most substantial increase, expanding by 2,652.9 ha, primarily due to the conversion of agricultural land. In contrast, agricultural land declined by 5,918.5 ha as a result of urbanization. Meanwhile, aquaculture land decreased by 1,615 ha, and forested areas experienced a slight reduction of 404.6 ha due to exploitation and land-use conversion. Landscape analysis indicates an increasing degree of land use fragmentation and diversity. The SDI index rose from 1.75 to 1.89, reflecting greater diversification of land use types. Residential and construction land in Ninh Bình city showed the highest increase in CA, NumP, and ED indices, highlighting rapid urban expansion. Although agricultural land area decreased, the NumP index increased from 278 to 305, indicating fragmentation due to conversion to other land types. The study confirms that urbanization and industrialization trends are intensifying in Ninh Bình city and Tam Điệp city, while agricultural and aquaculture land is shrinking. The landscape approach provides a quantitative assessment of land use changes, supporting planning and sustainable development efforts.

Isolation of alginate from drifting Seaweed and its application in the preparation of bioactive hemostatic beads

Nguyễn Đức Toàn, Nguyễn Thành Dương — Mon, 07 Jul 2025 09:45:40 +0700

The increasing accumulation of drifting seaweed along Vietnam’s coastal regions poses significant environmental and economic challenges. Utilizing this abundant biomass to produce high-value products represents a sustainable approach to environmental management and circular economy development. This study focuses on the isolation of alginate from drifting seaweed (Sargassum) collected from the coastal area of Quang Ninh, and its application in the preparation of bioactive hemostatic beads. After cleaning and removing impurities, the seaweed was extracted with sodium carbonate solution, followed by ethanol precipitation and drying. The alginate yield reached approximately 36,2 % relative to the dry seaweed mass. FTIR analysis confirmed the presence of characteristic alginate functional groups (O-H, COO⁻, C-O-C), consistent with commercial alginate. The extracted alginate was used to fabricate hemostatic beads via gelation and cross-linking with Ca²⁺ ions. In vitro tests in animal blood models showed that the hemostatic particles were able to form gel after 45 ± 5 seconds when in contact with blood fluid, with no cytotoxicity observed in MTT assays on fibroblast cell lines. These findings indicate that alginate from drifting seaweed has potential as a safe biomedical material and contributes to the treatment of coastal waste.

Current status of plastic waste generation at Chau Van Liem high school, Can Tho city

Nguyễn Thanh Giao, Lý Trúc Giang, Quách Nguyễn Huyền Diệu — Mon, 07 Jul 2025 09:46:46 +0700

Plastic waste pollution is an urgent global issue, and in Vietnam, seriously affecting human health and the environment. This study was implemented to assess the current use, generation, and management of plastic waste at Chau Van Liem High school. The data were collected by 306 interviewing students at three grades 10, 11 and 12 using Google Forms. The generation and composition of plastic waste were evaluated by collecting, classifying, and weighing waste on campus. The results revealed that the total volume of plastic waste ranged from 72.33 kg to 81.00 kg, with the generation coefficient ranging from 0.040 to 0.045 kg/person/day. The mainly of plastic waste is plastic cups, accounting for 40.03 %, plastic bottles for 25.54 %, foam boxes for 18.10 %, plastic straws and spoons for 9.96 %, and plastic bags for 6.37 %. The high school could increase the dissemination of issues of single-use plastic waste through teaching and extracurricular activities within the school, which would help increase knowledge and thereby change students' plastic usage behavior.

Greenhouse gas inventory and proposed emission reduction solutions at Vu Gia International Company Limited, Ha Nam province

Đỗ Nhật Long, Hoàng Anh Huy — Mon, 07 Jul 2025 09:49:01 +0700

The scope of the inventory includes scope 1 and scope 2. The results of the greenhouse gas inventory at the company in 2023 show that the total converted emissions are 11,359.095 tons of CO₂e. Of which, the largest source of emissions is from grid electricity use, with 11,137.189 tons of CO₂e, accounting for 98.046 % of total emissions. The second source of emissions is from stationary and mobile fuel combustion processes, generating 221.906 tons of CO₂e, accounting for 1.954 %. To reduce greenhouse gas emissions, the study proposes several solutions such as: (i) changing to energy-saving lighting equipment, (ii) using renewable energy, (iii) closing the main compressed air supply valve during lunch breaks, (iv) replacing belt-driven fans with direct-driven ventilation fans, and (v) implementing an energy management system. These solutions aim to improve energy efficiency and reduce the environmental impact of the plant.

Research on the effect of lignocellulose hydrolysis methods from pinus wood chips to recover glucose

Nguyễn Thị Phương Mai, Vũ Văn Long, Nguyễn Thị Danh — Mon, 07 Jul 2025 09:51:09 +0700

Glucose production from lignocellulosic biomass of pine wood chips is a key factor contributing to reducing the total cost in the process of converting biomass into ethanol and the enzymatic hydrolysis of cellulose brings more benefits than chemical treatment methods thanks to the flexible activity of enzymes, no environmental pollution, high efficiency and the creation of the least by-products. Steam enzymatic hydrolysis at high solid concentrations must overcome the resistance in the hydrolysis process, such as high reaction rates and high glucose concentrations. An optimal control strategy for the hierarchical hydrolysis process - batch has been studied to solve the above problems, conducting the incremental addition of substrate at the rate of 25 %/time (corresponding to being fed - batch 4 times) at times such as 0 h, 6 h, 12 h and 18 h. The cellulose conversion process is maximized and the maximum glucose concentration is accumulated during the incremental substrate time (fed - batch), reaching 190.1 g/L with a recovery efficiency of 70.7 %, the largest hydrolysis rate of 3.55 (g/L × h). After 96 hours of hydrolysis, the hydrolysis efficiency increased by 93.7 %, and the glucose concentration reached 252 g/L.

Ecomorphological characteristics of Ben En National Park, a multi-sectoral approach for sustainable development

Mon, 07 Jul 2025 00:00:00 +0700

Ecogeomorphology is an interdisciplinary research approach that focuses on the two-way relationship between geomorphological systems and ecosystems. Researchers from various disciplines (geology, geomorphology, groundwater, surface water, biology, climate, ecological landscape, and socio-economics) collaborated to conduct surveys, collect and process data. The results identified: a list of ecosystem service types provided by Bến En National Park; Integration of geomorphological map and ecological map to establish ecogeomorphological map and evaluate their potential ecological service for classified map units. This evaluation was based on a scoring method: “+1” for landforms that can provide a service, “0” for those with no or unclear capacity, and “-1” for landforms that limit the ability to provide ecosystem services. The evaluation scores were processed to build up an ecogeomorphological map with 8 units, representing the spatial distribution and diversity of ecosystem services.

Developing a process to assess the load-bearing capacity of the Tam Diep river in Bim Son town, Thanh Hoa province to serve water resource quality management

Bùi Đức Tấn, Lê Ngọc Thuấn — Mon, 07 Jul 2025 09:54:00 +0700

In the process of assessing the wastewater reception capacity of water sources, it is necessary to use the precautionary principle by considering and fully considering the negative impacts at the highest level that the wastewater can cause on the purposes of using water sources and using the safety factor for all calculations. The most negative impacts often occur during the dry season, corresponding to this period, the wastewater reception capacity of water sources is often at its lowest level. In the assessment parameters, the Tam Diep river is no longer able to receive BOD₅, TSS. The results of the process calculation by direct and indirect methods show that the BOD₅, TSS content have exceeded the limit of the allowable discharge threshold. For NO₂^-by direct and indirect methods, the Tam Diep river can still receive about 1635 kg/day, corresponding to the coefficient Fs = 0.5. In the process of assessing the discharge receiving capacity of Tan Diep river according to QCVN 08:2023/BTNMT for surface water type B. For surface water quality type A, the Tam Diep river is no longer able to receive organic matter due to the largest BOD₅ at the time of monitoring compared to QCVN 08:2023/BTNMT. Developing a process to assess the load-bearing capacity of the Tam Diep river in Bim Son town, Thanh Hoa province to serve water resource quality management is important and necessary.

Current status of generation and composition of domestic solid waste in Phong Dien town, Phong Dien district, Can Tho city

Nguyễn Ngọc Hoa, Nguyễn Thanh Giao — Mon, 07 Jul 2025 09:55:34 +0700

Domestic solid waste is generated daily, consequently causing serious environmental problems. This study aimed to assess the current generation, composition, and management practices of domestic solid waste in Phong Dien town, Can Tho city. Data were collected through field surveys, interviews with 30 households, and direct waste sampling from 15 households. Descriptive statistics were employed for data analysis. The research results indicated a domestic solid waste generation rate of approximately 1.3 kg/person/day in the study area. Organic components constituted the largest fraction at 82.8 %, followed by nylon (7.9 %) and plastic (3.4 %). Other elements were present in smaller proportions: Paper (2.7 %), metal (1.6 %), glass (0.7 %), fabric (2.8 %), rubber (1.6 %), and ceramics/shells (1 %). Hazardous waste constituted 1.2 % of the domestic solid waste stream. The total estimated domestic solid waste generation for the town was 7.5 tons/day. Local environmental management officers have conducted awareness campaigns and displayed banners regarding solid waste management. However, the reported rate of household waste classification was only 53 %. Furthermore, the collection rate reached only 70 %, the remaining waste was reportedly burned, disposed of in the river, or dumped on open land. These findings provide valuable scientific information for improving domestic solid waste management in the study area. Further efforts should focus on educating residents on source separation techniques, alongside enhancing inspection, monitoring, and overall management of household solid waste.

Study on sample pre-treatment and selection of optimal conditions for aluminum (Al) leaching from solar panel modules

Nguyễn Thành Trung, Trịnh Kim Yến — Mon, 07 Jul 2025 09:56:31 +0700

This paper presents the experimental results on the sample pre-treatment process and aluminum (Al) extraction from solar panel modules. In this study, the solar panel modules were cleaned, cut into small pieces, and pre-treated to separate the tempered glass from the surface of the solar panel modules. The remaining material was then heated, ground into fine powder, and used for aluminum extraction. Experimental results show that the pre-treatment process with Toluene solvent at 450 ^oC resulted in 54.4 % tempered glass and 12.3 % metal fibers, with the remaining powder accounting for 33.3 %. The pre-treated samples were then subjected to aluminum extraction using a NaOH 5 M solution through wet inorganic dissolution. The research indicates that the optimal solid-to-liquid (S:L) ratio is 1 g sample/15 mL NaOH 5 M, achieving a dissolution efficiency of 65.5 %. The chosen dissolution time was 60 minutes at 60 ^oC, yielding a dissolution efficiency of 76.2 %.

Greenhouse gas inventory at Nam Vang joint stock company, Chau Son industrial park, Phu Ly city, Ha Nam province

Phạm Thị Mai Thảo, Nguyễn Phương Thúy, Lê Thị Trinh — Mon, 07 Jul 2025 09:57:37 +0700

This study was conducted to inventory greenhouse gas (GHG) emissions by Circular No. 38/2023/TT-BCT dated December 27, 2023, which provides technical guidelines for measuring, reporting, and verifying GHG mitigation in the industry and trade sector. Additionally, the study proposed solutions to reduce GHG emissions at the Nam Vang joint stock company. Nam Vang Joint Stock Company operates in the field of plastic production, with a total energy consumption of 5,586 TOE, and is on the list of greenhouse gas emission facilities that must conduct greenhouse gas inventories in the Industry and Trade sector according to Decision No. 13/2024/QD-TTg of the Prime Minister. The scope of the emission inventory includes Scope 1 (direct emissions) and Scope 2 (indirect emissions from energy use). The 2023 inventory results show that the total emissions of Nam Vang joint stock company from sources in scope 1 and scope 2 are converted to 10,375.359 tons of CO_2e. Of which: The largest emission source is from grid electricity use: 10,255.382 tons of CO_2e, accounting for 98.8 %. The second largest emission source is from stationary and mobile fuel combustion processes with the amount of greenhouse gases generated of 79.237 tons of CO_2e, accounting for 1.2 %. The research results provide data for businesses to have a basis to propose solutions to reduce greenhouse gas emissions accordingly.

Current situation and solutions to improve the effectiveness of real estate brokerage activities - A case study in Hanoi city

Mon, 07 Jul 2025 09:58:35 +0700

This study aims to evaluate the current status and propose solutions to enhance the effectiveness of real estate brokerage activities in Hanoi, Vietnam. The research employs a combination of secondary data collection, primary surveys, data analysis techniques, and comparative methods. Findings from enterprise-level surveys indicate that only 30 % of real estate brokers receive regular training prior to practice. Moreover, 50.91 % of brokerage firms report frequent updates of real estate information, while 43.64 % of brokers lack access to smart devices in their professional activities. Customer satisfaction was measured across five key dimensions. The organizational and management factor received an average score of 4.12; Brokers’ responsibility scored 4.22; Information technology application scored 4.06; Individual characteristics of brokers scored 4.07, and legal knowledge was rated lowest, at 3.98. Based on these findings, the study proposes several solutions: Improving data infrastructure, expanding professional training programs, promoting the application of information and communication technology, standardizing operational procedures, enhancing professional ethics, and improving customer service quality. These recommendations aim to contribute to a more transparent, efficient, and trustworthy real estate market in Hanoi.

Assessment of the compatibility of the dredged material dumping plan in the coastal waters of Duyen Hai, Tra Vinh province with international standards and practices

Mạnh Nguyễn; Nguyễn Đức Toàn — Mon, 07 Jul 2025 09:59:51 +0700

This study evaluates the conformity of the proposed offshore dumping plan for dredged material in the coastal waters of Duyen Hai (Tra Vinh, Vietnam) with international standards and best practices in marine environmental management. The analysis highlights areas of alignment and gaps by comparing the current Vietnamese legal and technical frameworks with guidelines from international conventions such as the London Convention and OSPAR, as well as practices in developed countries. The findings suggest that while the Tra Vinh project complies with national regulations, several aspects - such as bioassays, material reuse potential, and long-term environmental monitoring - remain underdeveloped. This paper recommends adopting an integrated Weight of Evidence approach, introducing multi-tier classification systems, and considering confined aquatic disposal (CAD) sites to improve the sustainability and environmental integrity of future dredged material management efforts in Vietnam.

Estimating cement - related emissions from Clinker production in Ninh Binh province and proposing greenhouse gas mitigation measures

Thái Thị Thanh Minh, Lại Ngọc Ánh Dương — Mon, 07 Jul 2025 10:00:50 +0700

The cement industry - characterized by high energy consumption and significant CO₂ emissions, particularly from clinker production - is one of the key sectors requiring close monitoring and control. This study conducts a CO₂ emissions inventory from cement production in Ninh Binh province using the Tier 2 methodology proposed by the IPCC (2006). Additionally, future emissions are projected over the next 11 years through Monte Carlo simulations, with uncertainty analysis conducted to enhance the reliability of the results. Findings reveal that greenhouse gas (GHG) emissions in Ninh Binh increased by approximately 14,62 %, from 7,5 million tons of CO₂ in 2016 to 8,6 million tons in 2019. However, due to the impact of the COVID-19 pandemic, emissions in 2020 decreased to around 7,7 million tons. Projections indicate that, if current trends continue, emissions could reach approximately 9,21 million tons by 2025 and exceed 10,55 million tons by 2030. To mitigate greenhouse gas emissions in Ninh Binh’s cement sector, it is necessary to reduce electricity consumption and adopt alternative fuel sources. It is estimated that without mitigation measures, Ninh Binh may incur around 309 million USD in environmental costs, including carbon tax and energy expenses. Through this research, the authors aim to contribute both data and methodological approaches to support Vietnam’s national greenhouse gas reduction targets, particularly within the cement industry. The study also seeks to bridge climate science and environmental economics, laying the groundwork for future interdisciplinary research.

Factors influencing students' intentions for green energy conversion in transportation

Mon, 07 Jul 2025 10:02:53 +0700

The trend towards energy conversion is considered a leading policy in today's fight against climate change and environmental pollution. In particular, Hanoi, the capital of Vietnam, has emphasized this practical requirement due to pollution levels that have reached alarming levels. In this study, we research the current situation, advantages, difficulties, and solutions for green energy conversion when participating in traffic. Based on the Theory of Planned Behavior (TPB) and a 5-level Likert scale, we identified factors that affect students' intention to convert to green energy, including beliefs, awareness of environmental responsibility, attitudes, and perceived behavioral control. On the other hand, female students have higher green energy conversion intentions than male students, and the factor of subjective norm does not have a significant impact. Therefore, the research team proposed several solutions to promote the intention of green energy conversion in transportation among students in Hanoi.

Research on building a phone sales website for ShadowCatz store

Đỗ Thị Nụ — Mon, 07 Jul 2025 10:03:48 +0700

Building a website to sell phones brings many important advantages, helping businesses reach customers more effectively and increase revenue. Customers can find and buy phones from anywhere, anytime; Not limited by geography like traditional stores. Reduce costs for renting premises, staff, and other operating costs; Easily optimize online advertising to attract target customers. Offer many promotions, discounts, and combos to attract customers; Easily integrate multiple payment methods, making shopping more convenient for customers. Manage products and orders easily: Integrate an inventory management system, help control products accurately; Track orders, deliver quickly and professionally. Increase reliability and brand recognition: Professional websites help customers trust the business more; Easily build your brand, create a difference from competitors. Integrate effective online marketing: Easily deploy Google Ads, Facebook Ads to attract customers; SEO helps the website rank high on Google, reaching more potential customers.