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Advocating proper phosphorus (P) fertilisation is necessary to save this limited natural resource and to save the investment in rice cultivation. This study aimed to evaluate changes in phosphorus availability, total phosphorus in soil, phosphorus buffering capacity, and phosphorus saturation in the long-term phosphorus fertilisation in the paddy rice system. Soil samples were collected in the harvest stage after seven consecutive crops over three years at Can Tho city, Vietnam. The applied phosphorus fertiliser rates were: no phosphorus fertilisation (P0), 17.4 kg P/ha (P17.4), and 26.2 kg P/ha as farmer's practice (P26.2). The results showed that the soil phosphorus buffering capacity in P0, P17.4 and P26.2 treatments was 9.49, 9.08 and 9.04 mg/kg, respectively. The degree of phosphorus saturation of P17.4 and P26.2 treatments ranged from 17.7% to 25.5%, showing the medium to high risk of phosphorus leaching. This study indicated that the application of phosphorus rate higher than 17.4 kg P/ha might result in the reduced soil phosphorus buffering capacity in the intensive rice cropping system in the Vietnamese Mekong Delta region. Our results implied that the application of a rate lower than 17.4 kg P/ha/crop could be extended to the other rice-growing (double/triple rice) areas in the Vietnamese Mekong Delta region or other paddy rice on alluvial soils in Asia.

Given that rice husk biochar has been shown to modulate salinity in salt-affected acid soils, the objective of this study was to investigate the effects of organic amendment of salinized acid soils on P fractions, enzyme activities, and associated rice yield. Four treatments, viz. Rice–Rice–Rice, [RRR]; Fallow–Rice–Rice, [FRR]; Fallow–Rice–Rice + 3 Mg ha−1 of compost [FRR + Comp]; and Fallow–Rice–Rice + 10 Mg ha−1 of biochar [FRR + BC] were established at Ben Tre and Kien Giang sites, Viet Nam, over six consecutive crops. Soil properties at harvest of the sixth crop showed that there were diverse patterns of fractionation between P forms with respect to treatment. Overarchingly, biochar increased labile and moderately labile inorganic P and organic P by 30% to 70%, respectively, whilst compost had a relatively modest effect on these pools. Soil phosphatase activities at crop tillering increased following the FRR + Comp and FRR + BC treatments compared with those in RRR, except for acid phosphatase at Ben Tre. At harvest, there were no significant differences between the enzyme activities among the treatments. Rice yield was positively correlated with the more labile forms of P, soil C, and acid phosphatase activity. In the absence of organic amendments, there was no effect of triple versus double rice crops being grown in one-year cycle. Repeated application of biochar (10 Mg ha−1 × 5 times) showed potential to increase grain yields and total soil C in salt-affected acid soils, via modulation of P transformations to more plant-available forms.

Mung bean residues stimulate the hatching of soybean cyst nematode (SCN). In our previous study, combined incorporation of mung bean residues and biochar into soil can be effective in suppression of the soybean cyst nematode (SCN), Heterodera glycines, in the upper layer soil. However, there are no data available as to whether such effects are transmissible, and could for example be manifest in subsoil zones where such incorporation is confined to topsoils, via water-based pathways. We evaluated the effects of leachate passage from a biochar-amended soil in an upper soil zone to a lower zone in a microcosm-based system, upon a range of physicochemical properties and density of SCN. Disturbed soil was filled in a total of 9 cylindrical cores with two layers. The upper layer (0–15 cm) was amended with biochar at rates equivalent to 0, 0.3% or 1.8%, with bulk density set at of 1.1 g cm−3. The lower layer (15–25 cm) without biochar amendment was compacted to 1.2 g cm−3. Mung beans were grown for two weeks and incorporated into the upper layer. Water was surface-applied to the cores 4, 6, and 8 weeks after mung bean incorporation. After 16 weeks, the upper and lower layer soils were separately collected and assayed. The presence of biochar in the upper layer reduced the abundance of free-living nematodes, mainly bacterivorous, but increased that of a predator genus Ecumenicus in this zone. In the lower layer of soil under a biochar-amended upper layer, available P and soluble cations were increased as were abundances of total nematodes including Ecumenicus, resulting in greater maturity index, basal and structure indices. Notably, SCN density was decreased in lower zones by more than 90% compared to zero-biochar controls. This demonstrates that the effects of biochar upon soil properties, including impacts on biota and plant pathogens, are transmissible.

Biochar has the potential for improving soil properties and supporting ecological functions, but it has negative impacts on soil organisms in some cases. This study aimed to assess the effect of biochar application at rates of 0 (B0), 5 Mg ha−1 (B5), 20 Mg−1 (B20), and 40 Mg ha−1 (B40) on soil nematode community under upland and flooded conditions in a short-term microcosm experiment. After biochar application, soil was incubated for 2 to 8 weeks and nematodes were identified for community composition, trophic structures, functional guilds, maturity index and metabolic footprints. The chemical properties of the soils were also analyzed. General linear model revealed that biochar increased soil pH, EC, NO3−-N, available phosphorus, total C, and C/N ratio, particularly in the highest application rate and shifted the composition of nematodes. The greatest abundances of omnivores (Mesodorylaimus, Thornenema), predator (Nygolaimus) and functional guilds of cp5 were observed in B5, resulting in greatest structure footprint and composite footprint, (omnivorous + predator) footprint and total biomass in B5. While abundances of nematodes tended to decrease with the biochar applicate rates, the abundance of Prismatolaimus was the highest in B40. During the 8-week incubation period, the abundances of Achromadora, Alaimus, Aporcelaimellus, Cryptonchus, Mononchus, and Tobrilus remained stable in upland conditions. Under flooded conditions, the abundances of almost all taxa were markedly lower than those under upland conditions irrespective of biochar application, except for Acrobeloides, Alaimus, Aphelenchoides, and Ditylenchus. We highlighted that 5 Mg ha−1 of rice husk biochar can be the optimum in shaping the nematode community.

During the last decades, global climate change has led to serious impacts on nature, environment and socio-economic development in several places, especially in coastal zones. Vietnam is one of the countries, which was significantly affected by climate change. Hence, establishing an integrated framework to analysis climate change impacts for 28 coastal provinces in the country is necessary. Determining the key effects of climate change requires an appropriate method. To solve this issue, this study aims to utilize the fuzzy analytic hierarchy process (Fuzzy-AHP) technique to evaluate the weight of criteria and sub-criteria of climate change. The results found that 3/28 provinces are highly vulnerable to climate change compared to 17/28 of medium areas and 8/28 of the lowest group. Especially, Ho Chi Minh City is the most vulnerable province by the influence of climate change since the area has a low terrain, concentrated population, and a key economic province in Vietnam. Furthermore, the Fuzzy-AHP technique was integrated into climate change vulnerability index to assist policymakers in deciding an effective adaptation planning. [ABSTRACT FROM AUTHOR]

DISC Profile (Dominance – Influence – Steadiness - Conscientiousness) is called the thorough person’s skill, become an effective tool for everyone to identify his or her personality, as well as the associate should revise for having good at communication habits of highlight. However, the model has been applied in some large companies but has not been used in Vietnamese universities. This research presents a survey of 237 students in the field of Industrial Management such as 65 students of freshmen, 92 students of sophomores, 40 students of juniors, and 40 students of seniors. The purpose of this research aims to determine the students’ personality so that academic consultants can provide their students with a better orientation strategy such as promoting their strengths, being the professional direction from the beginning. DISC Profile (Dominance – Influence - Steadiness - Conscientiousness) - Thuật thấu hiểu lòng người là công cụ để mỗi người tự nhận diện tính cách của mình cũng như đối phương, từ đó có cách giao tiếp phù hợp nhất. Mặc dù, mô hình đã được áp dụng tại một số công ty lớn, nhưng chưa được áp dụng trong môi trường đại học tại Việt Nam. Bài viết trình bày kết quả khảo sát 237 sinh viên các năm như 65 sinh viên năm nhất (K41), 92 sinh viên năm hai (K40), 40 sinh viên năm ba (K39), 40 sinh viên năm cuối (K38) của ngành Quản lý Công nghiệp. Mục đích của nghiên cứu là xác định tính cách sinh viên từ đó giúp cố vấn học tập định hướng giáo dục sinh viên tốt hơn như định hướng cách phát huy tính cách nổi trội của họ, định hướng nghề nghiệp từ ban đầu.

Sinh viên trợ giảng (SVTG) có nhiều đóng góp tích cực trong việc cải tiến phương pháp giảng dạy theo định hướng lấy người học làm trung tâm. ở các trường đại học có nền giáo dục phát triển trên thế giới, mô hi?nh na?y đa? đươ?c a?p du?ng rô?ng ra?i. Tuy nhiên, mô hình sinh viên trợ giảng tại các trường đại học ta?i Việt Nam còn rất mờ nhạt và chưa được quan tâm đúng mức. Bài viết này sẽ tập trung phân tích các vấn đề cần quan tâm trong việc tuyển chọn, tập huấn và quản lý sinh viên trợ giảng. Thêm vào đó, bài báo cũng đề cập đến lợi ích của công ta?c trợ giảng đối với giảng viên, bản thân sinh viên trợ giảng và sinh viên tham gia học phần có áp dụng sinh viên trợ giảng; và một số ý kiến đóng góp xung quanh việc áp dụng mô hình sinh viên trợ giảng tại Trường Đại học Cần Thơ.

Để đảm bảo chất lượng đào tạo cho sinh viên ngành kỹ thuật đạt chuẩn đầu ra, đáp ứng nhu cầu đòi hỏi của xã hội hiện nay đòi hỏi sự quan tâm đến nhiều yếu tố, đặc biệt là phương pháp giảng dạy trong quá trình đào tạo. Bài viết này giới thiệu một số phương pháp giảng dạy tiên tiến giúp sinh viên ngành kỹ thuật học tập chủ động nhằm lĩnh hội tốt kiến thức, phát huy những kỹ năng mềm và tính sáng tạo của người học. Với các phương pháp giảng dạy mới này giúp sinh viên cuốn hút vào các hoạt động học tập một cách chủ động do giảng viên tổ chức và hướng dẫn, sinh viên sẽ khám phá ra những điều mình chưa hiểu rõ, cũng như chưa thực hiện tốt chứ không phải tiếp thu tri thức một cách thụ động. Ngoài ra, sinh viên sẽ tham gia nghiên cứu vào những tình huống thực tế, thảo luận, trao đổi nhóm, đưa ra những ý tưởng mới, phát huy những kỹ năng mềm như kỹ năng giao tiếp, kỹ năng trình bày báo cáo, kỹ năng máy tính,? Từ đó lĩnh hội tốt những kiến thức mới và nâng cao tính sáng tạo.