An Giang University

Abstract This study investigates the vertical settlement behavior of marine clay beneath a raft foundation under varying groundwater levels (GWL). Laboratory testing conducted in accordance with Vietnamese Standards (TCVN) and numerical simulations using the Finite Element Method implemented in PLAXIS 3D were performed to evaluate ground deformation characteristics. Experimental results show that the maximum settlement reached 20.77 cm at a GWL depth of 22.3 m under a loading of 800 kN/m². Within the GWL range of 15.3–19.5 m, the total deformation modulus ( K deformation ) , cohesion ( K cohesion ) , and Young’s modulus ( K Yeelastic ) were 44.38 kN/m², 40.2 kN/m², and 200.78 × 10² kN/m², respectively. The shear resistance ( K shear resistance ) attained 124.1 kN/m² under 200 kN/m² loading, corresponding to a vertical displacement ( K dis ) of 0.052 cm at 14.8 m depth. In contrast, numerical simulations predicted a higher maximum settlement of 150.7 cm, with simulated cohesion ( C simu ) and Young’s modulus ( E simu ) of 32.2 kN/m² and 141.2 × 10² kN/m², respectively. Pore water pressures reached 227 kN/m² at 7.3 m depth, associated with a settlement ( K simudis ) of 25.180 cm. The results demonstrate the significant influence of groundwater level fluctuations on settlement behavior and provide a reliable reference for foundation design on marine clay in coastal regions.

Baby maize (Zea mays L.) is a high-value horticultural crop widely cultivated due to its short growth cycle and strong market demand. However, intensive production systems often rely heavily on chemical fertilizers, leading to reduced nutrient use efficiency and potential soil degradation. The present study investigated the potential of the Priestia megaterium Thr45 to enhance soil fertility, improve crop performance, and optimize fertilizer management in baby maize cultivation. A field experiment was conducted using a three-factor factorial design consisting of bacterial inoculation, different urea application rates, and different KCl rates. Soil chemical properties, plant growth parameters, yield components, and nutrient composition of edible cobs were evaluated. The results showed that inoculation with P. megaterium Thr45 significantly increased available phosphorus and exchangeable potassium in soil compared with the non-inoculated control. Inoculated plants exhibited higher chlorophyll content, greater leaf development, and increased plant height during early growth stages. Bacterial inoculation also significantly improved yield components, including ear number, ear yield, edible cob yield, and plant biomass. Furthermore, the nutritional quality of baby corn was enhanced, as reflected by increased protein and mineral (N, P, and K) concentrations in edible cobs. Significant interactions between bacterial inoculation and fertilizer treatments indicated that the beneficial effects of P. megaterium Thr45 were closely associated with nutrient management practices. Notably, comparable yield and nutritional quality were achieved under reduced nitrogen and potassium fertilizer inputs when combined with bacterial inoculation. These findings highlight the novel potential of P. megaterium Thr45 as an effective biofertilizer for improving nutrient availability, maintaining high productivity, and supporting sustainable baby maize production with reduced chemical fertilizer inputs

Rice cultivation is the largest source of methane (CH4) emissions in Vietnam’s agricultural sector, making accurate quantification of these emissions critical for national GHG inventories and the design of mitigation policies. Currently, for UNFCCC GHG reporting, Vietnam primarily employs IPCC Tier 2 approaches using national emission factors combined with Tier 1 scaling factors. With the implementation of large-scale mitigation projects and Vietnam’s ambition to achieve Net Zero by 2050, Methane Global Pledge commitment by 2030, and joining international carbon markets, there is an urgent need to transition towards higher-tier methodologies. However, also process-based model (Tier 3) outputs are associated with uncertainty, which needs to be benchmarked first with established Tier 1 and 2 emission estimates.In this study, CH4 emission data from 13 Vietnamese field experiments are split into two groups—one with comprehensive management information (sufficient data) and one with sparse information (limited data)—to test IPCC Tier methods under different activity data conditions. Furthermore, for Tier 3, an inter-comparison is conducted between two biogeochemical models, DNDC and LandscapeDNDC. The evaluation focuses on the performance in estimating rice yields, seasonal CH4 emissions, and daily flux dynamics, while also analyzing the impact of different model parameterization and simulation setups.Our evaluation shows that Tier 1 significantly underestimates CH4 emissions, whereas Tier 2 provides a substantial improvement and remains robust across varying soil and management conditions. In contrast, Tier 3 outperforms Tier 2 only when comprehensive management data is available, reflecting its distinctive capacity to represent daily emission dynamics and management-driven peaks. Consequently, while Tier 2 remains a practical choice for national inventories, Tier 3 is essential for high-resolution mitigation assessments, particularly for large-scale emission reduction evaluations where detailed management data are comprehensively collected and systematically organized. The process-based model comparison reveals that while DNDC and LandscapeDNDC show similar performance under continuous flooding, they diverge significantly under Alternate Wetting and Drying (AWD) regimes. These discrepancies are primarily attributed to the models' different concepts of representing water table fluctuations.Building on these results, the Tier 3 approach of LandscapeDNDC was integrated into the web‑based LUI‑RICE platform (https://ldndc.online/rice/). This makes GHG quantification for Vietnamese rice cultivation directly accessible to local stakeholders and policymakers, translating the scientific findings of this study into a practical decision-support application.

This study investigates the relationship between government spending, renewable energy development and carbon intensity in Vietnam, where carbon intensity is used as an indicator of green economic performance. Using annual time-series data for the period 2000–2021, an autoregressive distributed lag (ARDL) model is employed to capture both short and long-run dynamics among the variables. The empirical results confirm the existence of a long-run equilibrium relationship. Renewable energy development is found to reduce carbon intensity in both the short and long run, thereby improving environmental quality and supporting the transition towards a more sustainable, low-carbon economy. By contrast, aggregate government spending does not exert a clear direct effect on carbon intensity, suggesting that broad-based fiscal expansion alone may be insufficient to foster green growth without complementary, environmentally targeted policies. The findings highlight the importance for policymakers of accelerating renewable energy deployment, mainstreaming sustainability considerations into urban planning, and aligning public investment in technology and infrastructure with low-carbon development objectives to achieve durable reductions in emissions.

Aiming to propose solutions for sustainable tourism development in Can Tho City, this study has adopted a qualitative approach to clarify key bottlenecks in the city’s tourism sector that hinder sustainability. Through focus group discussions and expert consultations, the study has identified bottlenecks related to economic benefits, environmental and tourism resources, and socio-cultural aspects. Based on these findings, the study has proposed several solutions to promote sustainable tourism in Can Tho City, including ensuring fair economic benefit distribution, protecting the environment and tourism resources, and preserving community culture.

This study aims to analyse the existing literature and identify major research trends at the intersection of organizational citizenship behavior and energy transition in energy-intensive industries. Data were retrieved from the Scopus database and include 155 English-language publications published between 2015 and 2025. A bibliometric analysis was conducted using R Studio (Bibliometrix/Biblioshiny) and VOSviewer to examine publication performance, influential journals and authors, geographical distribution, and thematic structures within the research domain. The results show a rapid expansion of research linking organizational behavior with energy transition, reflecting increasing scholarly attention to the behavioral and organizational dimensions of energy efficiency and low-carbon transition. The literature is mainly published in high-quality journals in energy economics, sustainability, environmental management, and organizational studies. Geographically, research activity is concentrated in Asia and Europe, with China emerging as the most productive contributor, followed by several European countries and other emerging economies. Keyword co-occurrence and thematic mapping identify four major research themes: organizational green management and sustainability foundations; pro-environmental and organizational citizenship behaviors and governance mechanisms; energy efficiency, energy consumption, and low-carbon transition dynamics; and system-level energy transition, policy, and stakeholder governance. The study also outlines future research directions to strengthen the integration of organizational citizenship behavior, energy economics, and sustainability perspectives in energy-intensive industries.