Hanoi University of Natural Resources and Environment

Can Gio District in southern Vietnam, including the Can Gio Biosphere Reserve and the urbanized beaches of Can Thanh Town, is a rapidly developing coastal area facing increasing pressures from marine plastic pollution. This study compared beach litter monitoring using 1 m × 1 m quadrats with in situ collection against smartphone imagery captured via the Mergin Maps app and later annotated in DotDotGoose. Mergin Maps was selected because it provides an open‑source, smartphone‑based GIS platform for rapid, low‑cost capture of georeferenced quadrat images, which is more feasible for routine monitoring in resource‑limited coastal settings than drone surveys or fully manual transect methods. Across four sandy beaches, at Bui Lam Beach field surveys recorded 399 items, while image-based analysis detected 410 items; at Bui Lam-Tac Xuat Beach, field surveys recorded 212 items, compared with 236 from image-based analysis, indicating strong tidal influence and clam farming activities at these sites. At Can Thanh Park, 189 items were counted in the field compared with 149 items in images, whereas at Tac Xuat, a tourist beach with regular cleanups, 82 and 71 items were recorded by field and image-based methods, respectively. Overall litter densities exceeded 10 items m⁻2 for both methods, and plastics accounted for more than 96

ABSTRACT Optimising the efficiency of applied nitrogen (N) fertilisers is essential to sustain agricultural systems. Substantial N losses continue through leaching, volatilisation, and denitrification processes. Co‐application of organic amendments and biochar alongside synthetic fertilisers is a widely practiced strategy to enhance N retention, improve soil fertility and increase crop productivity. Previous studies have focused on the specific characteristics of soil amendments and the magnitude of yield change, while N use efficiency (NUE) and economic returns remain uncertain. This meta‐analysis examined the effects of synthetic fertiliser applied alone, co‐applied with biochar and co‐applied with organic amendments, on crop yield, plant N uptake, NUE and economic return within rice cropping systems. Synthetic fertiliser and biochar applied alone increased rice yield by 69.2% ± 30.3 and 33.4% ± 34.9, respectively (Bootstrap 95% CI), whereas yield further increased by co‐applying biochar (+104.8% ± 37.5) and organic amendments (+80.2% ± 18.2) with fertiliser compared with non‐fertilised control. Co‐applying organic amendments (+20.9% ± 29.7) and co‐applying biochar (+35.1% ± 18.3) with synthetic fertiliser increased NUE compared with fertilised control. For rice crops under low N application (< 150 kg ha−1), co‐applying biochar with fertiliser increased yields more than co‐applying organic amendments (+70.1% ± 0.7 vs. +52.5% ± 0.3, respectively). Within acidic soils, co‐applying biochar with fertiliser (+72.9% ± 0.4) led to higher yield than co‐applying organic matter (+36.0% ± 0.9), and among soils with high organic carbon concentration, co‐applying biochar with fertiliser increased yield by 97.6% ± 1.6, compared with yield increases observed by co‐applying organic matter with fertiliser at 29.4% ± 0.5 and fertiliser alone at 25.6% ± 0.2. The main factors driving rice yield were N application rate, co‐application method and soil organic carbon concentration. Co‐applying either biochar or organic amendments did not significantly differ in benefit–cost ratio with benefit–cost ratios of 35.1% ± 9.2 and 18.1 ± 26.5, respectively compared with fertilised control. Co‐applying either biochar or organic amendments with synthetic fertilisers decreased N inputs and increased economic return, therefore improving sustainability in rice cropping systems.

This study scrutinizes the significance of tax avoidance and earnings quality in shaping firm performance in Vietnam, a frontier emerging market. The study examines how tax avoidance and earnings quality influence firm performance, using return on assets (ROA) and return on equity (ROE) as performance indicator. The analysis is conducted on panel data covering the period from 2015 to 2022, with further comparisons made across the before and after COVID-19 periods. The study used panel data analysis to evaluate 3,360 observations of non-financial public firms in Vietnam. Empirical results reveal a negative effect of earnings quality on ROA and ROE. While tax avoidance shows a positive impact on ROE across all periods, its effect on ROA turns negative in the post-COVID period. This result indicates that the benefits of tax planning may be reduced under economic uncertainty. The study enriches existing literature by offering context-specific evidence drawn from a transitional economy, highlighting the importance of strengthening corporate governance and regulatory enforcement to ensure the effectiveness of financial reporting and tax strategies in value creation.

In this work, Ag– and N– modified TiO2 photocatalysts were synthesized via a solvothermal method and characterized to evaluate their photocatalytic performance toward cyanobacterial inactivation and microcystin-LR degradation. The modified materials exhibited reduced band-gap energies of 3.00 eV (N–TiO2), 2.45 eV (Ag–TiO2), and 2.17 eV (Ag, N–TiO2) indicating enhanced visible-light absorption. Photocatalytic treatment of Microcystis aeruginosa (∼106 cells mL-1) at catalyst dosage of 0.3 g L-1 showed high removal efficiencies of 89.1 ± 0.9 – 96.3 ± 0.1% under UV light (365 nm) and 81.8 ± 1.7 – 95.0 ± 1.0% under visible light. Ag, N–TiO2 exhibited the highest activity and achieved complete MC-LR degradation within 16 h. Both cyanobacterial inactivation and MC-LR degradation were consistent with the Hom kinetic model, suggesting the combined contributions of photolysis and adsorption. A tentative MC-LR degradation pathway under UV irradiation was proposed based on ESI–MS analysis. The enhanced photocatalytic performance is attributed to the synergistic effects of nitrogen modification and Ag deposition, which improve visible-light absorption, facilitate charge separation, and promote hydroxyl radical generation. These findings highlight the potential of Ag, N–TiO2 photocatalysis for controlling cyanobacterial blooms and associated toxin contamination in water.

This study aims to identify the factors affecting the intention to use data analytics (DA) tools by auditors in independent auditing firms in Hanoi. Using a qualitative research method through a systematic literature review, the paper analyzes and synthesizes secondary data from reputable academic works and professional reports. The main research result is the proposal of a comprehensive theoretical model, developed based on the Unified Theory of Acceptance and Use of Technology (UTAUT), which identifies five core factors influencing auditors' intention to use DA: Perceived Usefulness, Perceived Ease of Use, Social Influence, Facilitating Conditions, and a crucial contextual factor, Auditor Competency. Consequently, the study provides significant managerial implications, recommending that auditing firms should develop clear technology investment and training strategies, educational institutions and professional associations should update their curricula, and auditors themselves should proactively enhance their capabilities. These recommendations provide a scientific basis for relevant stakeholders to promote digital transformation, thereby improving the quality and competitiveness of the Vietnamese audit industry. The novelty of the research lies in filling an academic gap by focusing deeply on DA tools within the specific context of an emerging market, while also constructing a theoretical model that integrates the factor of individual competency, thereby providing a valuable analytical framework for future empirical research.