Hue University Journal of Science: Agriculture and Rural Development

ASSESSMENT ON SOME OF SANDY SOIL PROPERTIES IN PHU VANG DISTRICT, THUA THIEN HUE PROVINCE

Pham Gia Tung — 2024-12-31

This study was conducted in Phu Da town and Vinh Xuan commune, Phu Vang district, Thua Thien Hue province, with the aim of evaluating and mapping soil properties, including pH_KCl, total nitrogen, electrical conductivity, total phosphorus, total potassium, and soil organic carbon. The results showed that most soil properties in the study area were low; the soil was poor in organic carbon and acidic, with a notable decrease in organic carbon content compared to previous studies (0.69% compared to 0.86%). Three out of six soil quality indicators—soil acidity, total nitrogen, and total phosphorus—showed statistically significant differences between land use types. This difference was observed between the two-season rice land use type and all other land use types. This study employs the Ordinary Kriging interpolation method for soil quality indicators mapping. However, the results indicate that the map's accuracy is relatively low. This finding suggests that conventional interpolation methods, which rely on distance and sample residuals, may not be appropriate for soil quality indicators mapping. Consequently, there is a need to explore and apply alternative methods to enhance mapping accuracy.

STUDY ON FACTORS AFFECTING URBAN SUSTAINABLE DEVELOPMENT IN DA LAT CITY, LAM DONG PROVINCE

Nguyen Hoang Khanh Linh — 2024-12-31

This study aims to build a set of environmental integrity indexes (EII) for urban planning and development in Da Lat city, Lam Dong province. The research methods include data collection method, interview survey method, data processing method, data analysis method and regression analysis on SPSS software to process data. The research results determines the influence of EII on sustainable urban development with heritage-specific properties in Da Lat city, ranked in order of impact level from largest to smallest: the most important level is of infrastructure development and architecture and urban landscape (β = 0.205), followed by Management (β = 0.115 heritage); Population group (β = 0.087); Group of historical roles and heritage factors in urban function (β = 0.062); and Group of Economy and The quantity, scale of heritage, relics have the same impact level (β = 0.058). Thus, it can be seen that for an urban area with specific characteristics of heritage, together with the socio-economic development of Da Lat, however, preserving the local cultural heritage is the most important. Regarding heritage characteristics in long-standing artistic architecture associated with urban development, the construction and development of infrastructure and urban architecture and landscape will interrupt the city's long-standing architectural heritage.

EFFECTS OF A NUTRITION SOURCE OF HYDROLYZED PROTEIN FROM WHITELEG SHRIMP HEAD (Litopenaeus vannamei) IN A PROCESS OF Trichogaster pectoralis’s NURTURING

Vo Van Song Toan — 2024-12-31

The study explored the use of small peptides and oligopeptides derived from hydrolyzed whiteleg shrimp head protein (Litopenaeus vannamei) to nurture Trichogaster pectoralis (Pearl Gourami). These peptide fragments were analyzed for amino nitrogen content and molecular weight using the OPA and SDS-PAGE methods. Two types of feed were tested: control feed (CF) and processed feed (PF), both containing fish meal, to evaluate the growth of Pearl Gourami. The results showed that both feeds led to low concentrations of dissolved oxygen (DO) (4.48 to 6.49 mg/L), chemical oxygen demand (COD) (16.09 to 24.98 mg/L), and biological oxygen demand (BOD) (16.62 to 22.61 mg/L), which were within the acceptable limits set by national aquaculture standards. Additionally, the survival rate of the fish remained highly, ranging from 94.8% to 99% after 60 days. In terms of growth performance, fish fed with PF exhibited weight gain (WG) of 7.00±0.76 g/fish, daily weight gain (DWG) of 0.117±0.014 g/fish/day, specific growth rate (SGR) of 0.672±0.065 %/g/fish, feed intake (FI) of 0.467±0.002 g/fish/day, and a feed conversion ratio (FCR) of 4.16±0.314. The digestibility coefficients of dry matter (ADC_DM), total protein (ADC_pro), and total lipid (ADC_Lip) for fish fed with PF were 66.2%±1.92, 90.4%±0.468, and 88.3%±0.576, respectively. Furthermore, the average meat weight of Pearl Gourami was 2.08±0.221 grams.

WILD BIRDS TRADED IN THE CENTRAL COASTAL PROVINCES, VIETNAM

Ho Thang — 2024-12-31

Wild bird trade in Vietnam has been widespread. From July 2023 to April 2024, a total of 35 bird shops and markets were surveyed in 5 Central Coast provinces including Thua Thien Hue, Da Nang, Quang Nam, Binh Dinh and Khanh Hoa. A total of 1,601 individuals belonging to 9 orders, 20 families and 53 species were recorded. Among the recorded species, 12 species are listed in the IUCN Red List (2024) and Decree No. 84/2021/ND-CP of the Government of Viet Nam. The results showed that the bird trading in the Central Coast provinces includes 3 different types: fixed pet bird shops (25 shops, accounting for 71.42%), vendors (08 locations accounting for 22.86%) and two locations selling released birds (5.72%). The prices are variable for each different species group: the released bird group had the lowest fluctuation ranging from 7,000 to 15,000 VND per individuals, the songbirds had the largest fluctuation from 50,000 to 2,500,000 VND, and the group for food (mainly migratory waterfowls) ranges from 30,000 – 300,000 VND. It is necessary to propose and implement solutions to limit and end the wild bird trades in the region as well as in Vietnam.

EFFECT OF CULTURE CONDITIONS ON β-1,3-GLUCANASE PRODUCTION BY Paenibacillus polymyxa M6

Hoang Ha My A — 2024-12-31

In this study, we isolated and optimized the culture conditions for β-1,3-glucanase biosynthesis by a highly enzyme-producing bacterial strains isolated in Thua Thien Hue province. Among the three isolates M6, DH2, and T5, strain M6 exhibited the strongest β-1,3-glucanase production with the strongest hydrolysis zone of 19.03±0.05 mm diameter. Strain M6 was identified through nucleotide sequencing by 16S rRNA region, showing a similarity of 99.72% with Paenibacillus polymyxa HGPJ-62 in the GenBank database (NCBI). The optimized medium composition and culture conditions for strain Paenibacillus polymyxa M6 were determined as follows: the β-1,3-glucanase induction medium comprised the following components: K₂HPO₄·3H₂O 1.3 g; MgSO₄·7H₂O 1 g; KCl 0.5 g; yeast extract 0.5 g; NaNO₃ 1 g; oat flour 5 g; pH = 6, incubation temperature 40–50°C for 24 hours, shaking speed 180 rpm, and inoculum ratio 1%. The β-1,3-glucanase activity reached 1.5 U/mL. The present study highlights the β-1,3-glucanase biosynthesis by strain M6, demonstrating its suitability for development and application for prevent gummosis disease in Thanh Tra pomelo trees as well as in controlling fungal pathogens with glucan-dominant cell walls.