Maximizing nutrient removal: unveiling the influence of biomass retention time in revolving algae biofilm reactor.

This study introduces a novel Revolving Algae Biofilm reactor for synthetic wastewater treatment, examining the influence of various biomass retention times (BRTs) on nutrient removal performance. The study reveals complex interactions between microalgae and bacteria, emphasizing their symbiotic functions in oxygen provision, nutrient absorption, and floc creation. This research contributes to the advancement of sustainable wastewater treatment methods, showing promise for large-scale nutrient removal in industrial settings.

Advancing sustainable rice production in the Vietnamese Mekong Delta insights from ecological farming systems in An Giang Province.

Rice serves as a crucial staple food crop for half of the world's population. In the Vietnamese Mekong Delta (VMD), rice production plays a vital role in national food security. However, the majority of the existing intensified rice cultivation schemes in the VMD, which are typically traditional, have rendered many farmers' livelihoods unsustainable due to issues such as land degradation, water pollution, health risks, and low profitability.

Recurrence interval of riverbed sand mining hotspots in the Mekong delta: Potential indications of unsustainable replenishment rates.

Rampant and illegal river sand mining in the Vietnamese Mekong Delta (VMD) has led to substantial sediment losses and bank erosion. However, regulation of this issue remains a significant challenge due to insufficient monitoring and enforcement efforts, partly attributed to limited data and technology. To support an improved monitoring system in the VMD, this study investigates the spatiotemporal changes in sand mining hotspots and their underlying drivers.

Accurate PM urban air pollution forecasting using multivariate ensemble learning Accounting for evolving target distributions.

Over the past decades, air pollution has caused severe environmental and public health problems. According to the World Health Organization (WHO), fine particulate matter (PM), a key component reflecting air quality, is the fourth leading cause of death worldwide after cardiovascular disease, smoking, and diet. Various research efforts have aimed to develop PM forecasting models that can be integrated into a solution to mitigate the adverse effects of air pollution.

Acute Exposure to Polyethylene Microbeads and Effects on the Water Flea Moina Macrocopa.

Microplastics merit attention as they can be ingested by lower trophic organisms, transferred to the food web, and pose potential risks to higher trophic levels. This study investigated the accumulation and effects of polyethylene microbeads (PEMBs, 63-75 μm) on adult water flea Moina macrocopa (600-800 μm), an order-magnitude difference in size, as a result of acute exposure. The organisms were exposed to PEMBs in four treatments of 0 (the Control), 5, 50, and 500 mg PEMB/L for examining PEMB accumulation, survival and reproduction of the organisms after the 24- and 48-h exposures.

Evolving pathways towards water security in the Vietnamese Mekong Delta: An adaptive management perspective.

The interplay of climate change, upstream hydropower development, and local water engineering interventions for agricultural production contributes substantially to the transformation of waterscapes and water scarcity in the Vietnamese Mekong Delta. This paper aims to examine how these dynamics are linked to the paradigm shift in water management in An Giang and Ben Tre, the two ecologically distinct provinces that face serious water scarcity in the delta. We used the adaptive management concept to examine how state-led policy directions from food security towards water security enable change in water management that gives priority to water retention.

Effective degradation of tetracycline in aqueous solution by an electro-Fenton process using chemically modified carbon/α-FeOOH as catalyst.

This study applied an electro-Fenton process using chemically modified activated carbon derived from rubber seed shells loaded with α-FeOOH (RSCF) as catalyst to remove tetracycline residues from aquatic environment. Catalyst characteristics were evaluated using SEM, EDS, XRD, and XPS, showing successful insertion of iron onto the activated carbon. The effects of the parameters were investigated, and the highest treatment efficiency was achieved at pH of 3, Fe: HO ratio (w/w) of 500:1, catalyst dose of 1 g/L, initial TCH concentration of 100 mg/L, and electric current of 150 mA, with more than 90% of TCH being eliminated within 30 min.

Water hyacinths retain river plastics.

Rivers represent one of the main conduits for the delivery of plastics to the sea, while also functioning as reservoirs for plastic retention. In tropical regions, rivers are exposed to both high levels of plastic pollution and invasion of water hyacinths. This aquatic plant forms dense patches at the river surface that drift due to winds and currents.

Valorization of the treatment of antibiotic and organic contents generated from an in-situ-RAS-like shrimp farming pond by using graphene-quantum-dots deposited graphitic carbon nitride photocatalysts.

In this study, we investigated the possibility of a photocatalytic system that uses graphene-quantum-dot (GQD)-deposited graphitic carbon nitride (g-C3N4) to treat tetracycline (TC) and other organic compounds generated from an in-situ-recirculatory-aquaculture-system (RAS)-like shrimp farming pond. GQDs were successfully deposited on the exfoliated g-C3N4 base through a hydrothermal treatment. The results showed that the incorporation of GQDs into the g-C3N4 enhanced its porosity without aggregating its mesoporous structure.

Emerging revolving algae biofilm system for algal biomass production and nutrient recovery from wastewater.

Toward the direction of zero‑carbon emission and green technologies for wastewater treatment, algae-based technologies are considered promising candidates to deal with the current situation of pollution and climate change. Recent developments of algae-based technologies have been introduced in previous studies in which their performances were optimized for wastewater treatment and biomass production. Among these, revolving algae biofilm (RAB) reactors have been proven to have a great potential in high biomass productivity, simple harvesting method, great CO transfer rate, high light-use efficiency, heavy metal capture, nutrient removal, and acid mine drainage treatment in previous studies.

Uncovering the lack of awareness of sand mining impacts on riverbank erosion among Mekong Delta residents: insights from a comprehensive survey.

Global sand demand due to infrastructure construction has intensified sand mining activities in many rivers, with current rates of sand extraction exceeding natural replenishment. This has created many environmental problems, particularly concerning riverbank stability, which adversely affects the livelihoods of people in the Vietnamese Mekong Delta (VMD). However, sand mining's social impacts in the region remain inadequately understood.

Pollution characteristics, associated risks, and possible sources of heavy metals in road dust collected from different areas of a metropolis in Vietnam.

Road dust samples were collected from different areas in Ho Chi Minh City (HCMC)-the largest city in Vietnam to explore pollution characteristics, ecological and human health risks, and sources of heavy metals (HMs). Results revealed the level of HMs found in the samples from residential and industrial zones of HCMC in the order of Mn > Zn > Cu > Cr > Pb > Ni > Co > As > Cd, Zn > Mn > Cu > Cr > Pb > Ni > Co > As > Cd. Due to the high enrichment of Cu, Zn in residential areas and Cu, Pb, Zn in industrial areas, the HM contamination in these areas remained moderate to severe.

Developing mango powders by foam mat drying technology.

Using mango purée from overripe mangoes to produce powders helped to solve agricultural product stagnation. The research investigates the effect of thickening additives, convection drying, and heat pump drying on bioactive compounds such as total phenolic content (TPC), total flavonoid content (TFC), color, and solubility of the final product. The obtained results showed that the mixture (gum arabic and maltodextrin in the ratio 50:50 w/w) at a concentration of 15% gave a good quality powder texture when dried by hot air convection at 55°C with TPC (21.

Identify Primary Air Pollution Sources of BTEX by Using Positive Matrix Factorization (PMF): A Case Study of Ho Chi Minh City, Vietnam.

Ho Chi Minh City (HCMC) is one of the main socioeconomic and financial centers of Vietnam. The city also faces serious air pollution. However, the city polluted with benzene, toluene, ethylbenzene, and xylene (BTEX) has rarely been studied.

Identifying the impact of land use land cover change on streamflow and nitrate load following modeling approach: a case study in the upstream Dong Nai River basin, Vietnam.

Tri An Reservoir is a vital source of water for agriculture, industry, hydropower, and public usage in Southern Vietnam. Due to human activities, water eutrophication has become a serious problem in recent decades. This study investigated for the first time the impact of land use and land cover (LULC) change on streamflow and nitrate load from the upstream Dong Nai River basin, which is the largest watershed of the reservoir.

Adaptive capacity of high- and low dyke farmers to hydrological changes in the Vietnamese Mekong delta.

This research assesses the adaptive capacity of farmers in the Vietnamese Mekong Delta's floodplains (VMD) with respect to hydrological changes. Currently, climate change and socio-economic developments induce extreme- and diminishing floods, which in turn increase farmers' vulnerability. This research assesses farmers' adaptive capacity to hydrological changes using two prevalent farming systems: high dykes featuring triple-crop rice farming and low dykes where fields are left fallow during the flood season.

Application of reaction-diffusion equations for modeling human and breeding site attraction movement behavior of mosquito.

This paper shows how biological population dynamic models in the form of coupled reaction-diffusion equations with nonlinear reaction terms can be applied to heterogeneous landscapes. The presented systems of coupled partial differential equations (PDEs) combine the dispersal of disease-vector mosquitoes and the spread of the disease in a human population. Realistic biological dispersal behavior is taken into account by applying chemotaxis terms for the attraction to the human host and the attraction of suitable breeding sites.

An Innovative Method for BTEX Emission Inventory and Development of Mitigation Measures in Developing Countries-A Case Study: Ho Chi Minh City, Vietnam.

Benzene, toluene, ethylbenzene, and xylenes (BTEX) are carcinogenic pollutants. However, the average concentration in 1 h of some pollutants belonging to BTEX, such as benzene, in Ho Chi Minh City (HCMC) is higher than the national standard QCVN 06:2009/BTNMT by about ten times. This research is the first to calculate the emission of BTEX for developing countries on a city scale.

Abundance and sources of plastic debris on beaches in a plastic hotspot, Nha Trang, Viet Nam.

Viet Nam is challenged by extensive marine plastic pollution, however, remediation efforts are hampered by undefined sources to the coastal environment. This study surveyed the abundance, type, and source of beached plastic litter at seven beaches along the coast of Nha Trang, Viet Nam. A total of 4754 beached plastic litter items (>2 cm) yielded a mean abundance of 19.

Outdoor air quality data for spatiotemporal analysis and air quality modelling in Ho Chi Minh City, Vietnam: A part of HealthyAir Project.

This article presents outdoor air pollution data acquired from the real-time Air Quality Monitoring Network (AQMN), which was established by the Healthyair project team in Ho Chi Minh City (HCMC), Vietnam. The AQMN is made up of six air pollution monitoring stations spread over the city (Traffic, Residential, and Industrial). Each station measures the same contaminants in the air, including PM, TSP, NO, SO, O, CO, and two meteorological factors, temperature and humidity.

Amoxicillin degradation ability of C1 isolated from catfish pond sludge in Vietnam.

The biological removal of antibiotic residue in the environment has earned great interest. This study presented the biodegradation of amoxicillin (AMX) using B. cereus C1 isolated from the catfish pond sludge in Vietnam.

A new integrated circular economy index and a combined method for optimization of wood production chain considering carbon neutrality.

The wood industry is potentially advantageous to applying the concepts of circular economy for sustainable development and can contribute to the commitment of carbon neutrality. This study developed an integrated circular economy index based on five different quantitative indicators for assessment of the wood production chain: heat recovery rate, CO sequestration rate, fossil fuel substitution rate, renewable electricity usage rate, and revenue increase from the by-products. A combination of best-worst method (BWM) and linear goal programming (LGP) techniques was investigated to develop an optimal circular economy model of wood processing chain for reduction in CO emission.