Baited pitfall traps represent a widely utilized method for dung beetle sampling. The effectiveness of this approach can be influenced by various factors, such as the type of bait used, trap size, and modifications to trap components. An important challenge during trapping is the inadvertent capture of non-target animals (such as: frogs, lizards, snakes, small rodents, and spiders), a concern that becomes more pronounced if endangered species are involved. To address these issues, incorporating a mesh panel into pitfall traps can help prevent unwanted intrusions. In this study, we assess the efficiency of baited pitfall traps covered with 2 cm mesh panels (BPTMP) for sampling dung beetles in tropical karst ecosystems within the Huu Lien Nature Reserve (northern Vietnam), comparing them with typical baited pitfall traps (BPT). The result revealed no significant differences in the species composition of dung beetles between the two trap types. Although the abundance of large-bodied dung beetles was significantly lower in BPTMPs compared to trap BPTs, the overall abundance and diversity of dung beetles did not significantly differ between the two trap types. Therefore, we strongly recommend adopting this sampling technique in studying on the diversity of dung beetles.
A comprehensive root database holds paramount importance for agro-forestry endeavours, providing valuable insights into the ecological characteristics and stability of plant species. However, the creation of such databases presents a formidable challenge. This study is devoted to shedding light on the spatial distribution characteristics of coarse roots (diameter ≥1 cm) in Populus simonii trees, which naturally flourish in Tongde County, Thanh Hai province, China. Ground-penetrating radar (GPR) technology was employed to investigate the distribution of these coarse roots, while tree root diameters were estimated through controlled experiments involving buried objects. A total of 40 P. simonii trees were meticulously selected for data collection, and the coarse roots of these trees were categorized into three diameter classes: 1-2 cm, 2-3 cm, and ≥3 cm. The study findings have unveiled a robust correlation between the density of coarse roots and the diameter at breast height (dbh) of the trees. Moreover, the total coarse root density moderately correlates with canopy width and tree height within a horizontal plane extending 3-5 m from the tree base and a vertical plane at a soil depth of 20-40 cm. This study underscores the effectiveness of GPR in elucidating the spatial distribution of tree roots and accurately estimating root diameters. This underscores the potential of GPR to significantly enhance investigations related to root ecology and below-ground biomass estimation.
Herb tea is tending to be consumed widely and increasingly in the world. In Vietnam, banana is one of the most popular fruits, but their peels are often wasted which can be reproduced in food processing. The purpose of this study was to determine the combination of banana-flavored water mixed with other herb extraction to create a kind of herbal drink meeting demand’s consumers. Therefore, banana peels were extracted directly in boiling water to create steam and condense water with a strong banana flavor. The optimal volume of banana-flavored water was 25 mL added into 100 mL herbal extract water. Among seven studied herbs, licorice with the number of 2 branches was accepted the most by panelists for herb tea’s sweetness and valued 3.8 for the taste sensory score in the 5 -point Hedonic scale. In addition, saffron with 3 branches was the best coloring agent for bright yellowness, determined 4.2 for the color sensory score. On the other hand, jujube (1 gram) was the best appropriate herb for the best flavour, well mixed with other herbs to produce the best acceptance by major panelists (the total sensory score of 14.6). The final herb tea product made by the selective recepi is potential to supply for the market a new healthy herbal drink.
The present study delved into the dynamics of tree communities in a specific area within Phou Khao Khouay National Park in Laos, distinguished by three distinct tropical forest types: Dry Evergreen Forest (DEF), Mixed Deciduous Forest (MDF), and Mixed Coniferous Forest (MCF). Conducted over a decade, from 2012 to 2022, we utilized data from a previous inventory carried out in 32 permanent plots, each measuring 50 m × 50 m. Trees with a diameter at breast height (DBH) ≥ 10 cm were identified, tagged, and measured for various parameters. In 2012, we documented 4,072 stems, amounting to 395 species existing within 155 families across the 32 plots, with a total area of 8 ha. By 2022, the number of stems had increased to 4,402, but the species and family counts had decreased to 311 and 135, respectively. Over the ten years, there was a notable increase in the number of stems, basal area (BA), and aboveground biomass (AGB), accompanied by a reduction in species and families. This study contributes valuable insights that can be utilized to enhance forest management practices. The observed trends provide a nuanced understanding of the dynamic nature of the forest ecosystems in the study area. The findings underscore the importance of considering individual forest types when implementing conservation strategies.
Understanding the maintenance of diversity and the assembly of communities is a primary concern in community ecology. This study explored the phylogenetic structure of an evergreen broadleaved tree community in Con Dao National Park, Vietnam. The survey, conducted in December 2023, encompassed all tree individuals with a diameter at breast height (DBH) ≥ 2.5 cm within a 4-ha study plot. These individuals were identified by species name, and their DBH was measured. Subsequently, a community phylogenetic tree was constructed using the Phylomatic online platform. The 4-ha study plot was subdivided into there different subplots based on three spatial scales (25 m × 25 m, 50 m × 50 m, and 100 m × 100 m) and all trees were classified into three different DBH classes (2.5 cm ≤ DBH < 10 cm representing small trees; 10 cm ≤ DBH < 20 cm as medium trees; and DBH ≥ 20 cm as large trees). The net relatedness index (NRI) and net nearest taxon index (NTI) were utilized to evaluate the phylogenetic structure and infer ecological processes. Our findings revealed a consistent decrease in both NRI and NTI with increasing spatial scales and tree sizes. These results suggest an overdispersed phylogenetic structure within the community across different spatial scales and tree sizes. Additionally, negative density dependence was found to have a pronounced effect on the phylogenetic structure, with a more significant impact on tree individuals from small and medium DBH classes than large ones. This study underscores the significance of phylogenetic density dependence as a primary mechanism governing species diversity and shaping the community structure of evergreen broadleaved forests in Vietnam.
The mechanical and flame-retardant properties of Acacia hybrid wood were studied through the treatment of an aqueous solution containing a styrene-acrylic copolymer (SC) and sodium silicate (SS). The results showed a significant increase in the mechanical properties of SC/SS-treated wood. Specifically, the modulus of rupture (MOR) and modulus of elasticity (MOE) improved by up to 71.54% and 53.65%, respectively. The surface hardness of the cross-section and radial section also increased by 37.24% and 46.65%, respectively. The treated wood’s weight percentage gain (WPG) reached up to 23.31%. The largest leaching rate (LR) of treated wood was only 8.01%, suggesting this treatment has obvious effects in fixing the SS in the wood. However, it did not cause positive bulking efficiency (BE) and anti-swelling efficiency (ASE). The incorporation of SS with SC resulted in the decomposition of polysaccharides at a lower temperature while increasing the limiting oxygen index (LOI), which was 34.95% higher than that of untreated wood, making it more difficult to ignite. Scanning electron microscopy (SEM) results showed that the SC/SS deposited in the cell lumina after polymerization, but significant structural changes occurred, including vessel and cell wall deformation due to the partial dissolution of hemicellulose and lignin from the cell wall in the alkaline solution. The results of this study demonstrate the feasibility of applying the SC/SS combination treatment to wood in practical applications.
Urban trees have been widely acknowledged providing a wide range of environmental services. They help to improve air quality by absorbing pollutants, crucial roles in magaging stormwater runoff etc., in urban environments. This study applied i-Tree Eco model to assess the structure of community trees and quantifies the environmental services and economic values in open public green spaces in Eco Park, Hung Yen province, Vietnam. To run the model, we collected profiles of 942 trees in the study area, including: location; species name; diameter at beast height (DBH, 1.3 m above ground); tree height values (crown tree height, canopy length, etc.); height under canopy (canopy width of East-West, South-North directions); canopy missing percentage; and crown light exposure. The result showed that all the tree species contributed to 990kg PM2.5 reduction (equal to 231,660 $/year); 1,338.4 (ton/year) carbon sequestration (equal to 13,384 $/year) and 26,772.1 (ton) carbon storage (equal to 267721 $/year); and 37,600.2 (m3) avoided runoff (equal to 79,712 $/year). Overall, Khaya senegalensis (Desr.) A. Juss. species was providing the most environmental services; Ficus subpisocarpa Gagnep. species was the most economically valuable with nearly 75 $/tree. Urban landscape design should consider these superior tree species into green infrustructure projects to maximize the environmental services and economic values.
Studying the diversity and ecological role of dominant species provides an important foundation for understanding the influence of dominant species on the diversity and biomass production capacity of plant communities. This study was conducted at the Nui Cau - Dau Tieng Protection Forest Management Board, Binh Duong province, to understand the diversity and ecological role of Dipterocarpus obtusifolius Teijsm. ex Mig. in the ecosystem forests. A total of 19 plots, each 0.1 ha in size (50 m x 20 m), were used for data collection. Trees with a diameter at breast height (dbh) ≥ 6 cm were recorded, including species name, number of individuals, dbh, and overall height. The study employed importance value index analysis (IVI%) and aboveground biomass (AGB) to assess the ecological role of dominant species. Findings revealed that: (1) Communities with dominant species had low species richness and fluctuating diversity levels, (2) The ecological role of dominant species varied across forest states, decreasing from very poor > poor > medium forests, and (3) Increasing IVI% and AGB% of dominant species influenced woody species structure and biomass output in the plant community. This study offers valuable insights to enhance forest management and quality in the area.
Mangrove forests have been globally recognized as they play a vital role in preventing coastal erosion, mitigating the effects of wave actions, and protecting coastal habitats and adjacent shoreline land-uses from extreme coastal events. Sentinel-1 (SAR) offers a new opportunity for mangrove cover mapping and biomass estimation, especially in the tropics where mangrove deforestation and degradation are highest and cloud cover is persistent. This study used the Sentinel-1A-derived VV/VH polarizations for mangrove cover mapping with thresholds of -23.5
The study applied GIS and Markov chains to assess land use changes in the period 2015-2020 and forecast land use change trends in Thach That district, Hanoi city until 2030. Using two maps of the land use status quo map in 2015 and 2020 of Thach That district and 2 period land statistics, the research result has established a land use change map in Thach That district for the period 2015 - 2020 for 16 types of land with a land change rate of 9.63% of the total natural area. During this period, the land types that tend to increase are Perennial crop land; Special-use Forest land; Aquaculture land; Other agricultural land; Residential land; Special-use land; Land for religious establishments; Land for beliefs establishments and Specialized water surfaces with an increased rate of 0.05-2.28%. In contrast, land types with a decreasing trend are Annual crop land; Production Forest land; Protective Forest land; Cemetery land, cemetery, funeral home, crematorium; Land of rivers, streams, canals and streams; Other non-agricultural land, and Unused land which decreased at a rate of 0.02-2.34%. It is forecast that by 2030, agricultural land will have 10,271.28 hectares (accounting for 54.90%), non-agricultural land will have 8,432.22 hectares (accounting for 45.07%), unused land will have 4.76 hectares (accounting for 0.03%). Performing a T-Test (Paired two sample for Means) between the area from the forecast and the planned area until 2030 shows that ρ = 0.979 > 0.05. Thus, it proves that the results of forecasting land use changes to 2030 using the Markov chain compared to the land use planning plan of Thach That district do not have too big a difference. The results of assessing land use changes and making forecasts of land change trends in the Thach That district contribute to helping policymakers have an objective view of land-use planning and economic development sustainably.
Understanding the composition of tree species is essential for establishing conservation priorities. Bu Gia Map National Park is in the tropical rainforest zone of Southeast Vietnam. This paper is to analyse and assess tree species composition and biodiversity conservation in Bu Gia Map National Park. The diversity of plant species in Bu Gia Map National Park was studied to provide baseline information for conservation and sustainable management processes that will prolong the life of National Park. The results obtained from the study conducted on the plant species composition and forest vegetation in this national park revealed a total of 786 species, spanning 430 genera and 132 families, across three divisions of vascular plants: Polypodiophyta, Pinophyta, and Magnoliophyta. Among these are 300 species of timber plants, 270 species of medicinal plants, 62 species of edible plants, 74 species of ornamental plants, 40 species of industrial plants, 28 species of fiber plants, and 12 species of plants with unknown use. Notably, during the investigation period, Goniothalamus vietnamensis Ban and Myxopyrum smilacifolium Blume were newly recorded in the forest vegetation of Bu Gia Map National Park. The study also describes a variety of forest vegetation in the area, identifying two major forest vegetation types within Bu Gia Map National Park.
This study employed high spatial resolution PlanetScope imagery at 3 m resolution for mapping burned area and burn severity resulting from a wildfire that occurred from April 7-9, 2023 in the highland of Vietnam. The wildfire took place in a protection forest near the Prenn pass in Da Lat city, Lam Dong province, Vietnam. Pre- and post-fire Normalized Difference Vegetation Index (NDVI) maps were generated using no-cloud high-resolution images acquired on March 25 and April 23, 2023 by the PlanetScope’s SuperDove satellites, respectively. The difference of NDVI (dNDVI) was then calculated, and thresholds, proposed by the author, were utilized to classify the study area into three different classes: unburned, low-to-moderate and high severity. The results showed that the total burned area was approximately 13.86 ha, with 8.19 ha classified as low-to-moderate severity, and 5.68 ha classified as high severity. Although there was no reference dataset to cross-validate the results, the estimated burned area is very close to the total affected area officially reported by the Forest Protection Department of Lam Dong province (about 13 ha). This study is one of the few that investigates the use of high-resolution PlanetScope imagery for environmental monitoring in Vietnam, and the first to focus on burned area and burn severity mapping in Vietnam. This work demonstrates the potential of PlanetScope images for mapping burned area and burn severity, particularly in small regions where other optical satellites, such as Sentinel-2 and Landsat, may not provide accurate results due to their spatial resolution limitations.
The results of early growths assessment of the Gao vang experimental planting area at the stage 7 year old and the selection of plus trees for big timber plantations show that the average growths in diameter at breast height, crown diameter, total height and trunk volume of plus trees (TG) reached a value of 16.74 cm; 5.24m; 10.74m; and 118.20 dm3 per tree, respectively, exceeding the accompanying forest tree group (ĐR) of 1.60; 1.02; 1.15; and 2.82 times, respectively, under the same comparison criteria, environmental conditions and time. The forest tree groups including, ĐR1; ĐR2; ĐR3; ĐR4; and ĐR5 had a coefficient of variation (CV%) in diameter of 19.07; 18.41; 13.45; 17.90; and 17.18%. Growth speed in diameter of plus trees including, TG4; TG3; TG2; TG5; and TG1 reached a value of 2.31; 2.40; 2.40; 2.41; and 2.43 cm per year, respectively, growth farther other forests tree group by 1.55 to 1.59 times. Exceed level (%) in diameter of plus trees including, TG1; TG2; TG3; TG4; and TG5. Forest trees groups reached a value of 31.75; 30.72; 31.97; 31.52; and 30.89%, respectively, that were better than the accompanying forest tree groups and the standards of plus trees for big timber indigenous plantating development. In total, there are over 1360 Gao vang individuals measured and evaluated, but only 5 excellent trees in growth could be selected, that had a exceed level for diameter of over 30% compared to the accompanying forest tree group, a ratio of 0.36%, and a selective intensity of 0.99. The plus trees evaluated and selected are very valuable as propagation materials, contributing to providing information, scientific basis, quality seed sources, and diversifying the structure of forestry tree varieties for the goal of developing big timber plantations with native species.
Compost, an organic fertilizer which is rich of nutrients, safe and environmentally friendly for crop cultivation. In this study, it was aimed at evaluatiton of the effects of the compost derived from shrimp pond waste sludge on plant growth of kohlrabi, white radish, and mustard green. The application of the compost produced in five districts (Quynh Luong, Nghi Hop, Dien Trung, Quynh Di, Hung Hoa) of Nghe An province resulted in remarkably higher plant growth. In which kohlrabi, white radish, and mustard green fertilized by the compost from Quynh Luong district had crop yields of 3.6 kg/m2, 3.4 kg/m2, 3.7 kg/m2 than the control without compost yielding 2.1-2.2 kg/m2. Similarly, other plant growth parameters of number and areas of leaves and survival rate of the plants were all significantly higher than that of the control. Moreover, the mustard greens yields applied the compost produced in the four districts including Nghi Hop, Dien Trung, Quynh Di, Hung Hoa were in the range of 3.1-3.6 kg/m2 all higher than that of the control unapplied fertilization determined as 2.2 kg/m2, but reaching relatively equivalent to that of the commercial organic fertilizer at 3.8 kg/m2, but slightly lower than that of the chemical fertilizer 4.4 kg/m2. The study revealed that the compost from shrimp pond waste sludge can be fertilized for crop cultivattion which was safe and contributing to reducing a large amount of waste sludge discharged from shrimp-raising ponds in Nghe An province.
Wild mushrooms are extensively gathered by rural communities throughout the uplands of northern Vietnam and nearby countries for food and medicine. These non-wood forest products are important for the livelihood of numerous rural communities. Many of these fungi form symbiotic relationships with the roots of certain species of forest trees, and the fruiting bodies can not be produced in artificial media. In the northeast region of the country, an edible red Russula (Nấm chẹo or Nấm hồng cô) has been harvested from under wild Castanopsis, Engelhardia and Lithocarpus trees by local people for a long time. However, the identity of this Russula is unknown. We collected basidiomes of this edible Russula in Cao Bang, Bac Giang and Quang Ninh provinces and described its morphological features. We used ITS rDNA and LSU rDNA sequence analysis to compare with other similar taxa in GenBank. Morphological and molecular analysis identified the taxon as Russula griseocarnosa, previously described from southern Yunnan, China. There is strong interest by local governments to commercialize R. griseocarnosa in Vietnam. However, over-harvesting could have detrimental effects on the population of this edible species. Therefore, further studies are needed to quantify the ecological requirements and to develop sustainable harvesting protocols of this edible species in Vietnam.
选用容器苗造林,是乡土珍贵树种造林推广 、森林质量精准提升 、天然林修复等项目中提高林分质量的有效措施之一.乳源木莲树干通直,是优良庭园观赏和四旁绿化树种,具药用 、经济等价值.本文乳源木莲采用6种不同基质及4种不同型号容器袋对比试验,结果表明:不同基质及不同的容器袋对乳源木莲苗期生长有影响,基质和容器型号对乳源木莲生长影响显著,基质和容器型号大小有交互作用.通过苗木质量 、育苗成本 、造林成本 、造林成活率等指标对比综合分析,采用基质配比(树皮50％:谷壳30％:泥土20％)和容器直径10 cm育苗效果较好.
This research work was conducted in order to investigate the effects of spent mushroom on Larch.The results showed that spent mushroom suitable for larch seedlings. There was significant difference from size.The best size was 2mm≤D<3mm.
接骨木是一种极具开发价值的木本油料作物,该文研究了不同浓度ABT-2生根剂对接骨木木扦插生根成活的影响.结果表明:ABT-2生根剂能显著提高接骨木扦插苗的生根率、生根数量、生根长度,其中当ABT-2在200mg/kg时提高接骨木生根率、生根长度的效果较高,但生根数量较其他两种浓度处理的少.
植物资源是一个地区自然生态系统的重要组成部分,系统地调查研究一个地区植物资源的状况,对于该地区经济发展和生态环境建设具有积极、现实意义。为了科学的开发利用和保护黑龙山丰富的野生植物资源,对黑龙山地区的植物资源进行了初步调查。采用野外植物学调查和实验室研究相结合的方法。据调查结果统计,黑龙山森林公园有植物86科739种,其中蕨类13科32种,裸子植物3科11种,被子植物70科696种。
This paper carried out individual plant and two strains and different planting density contrast test,analysis the effects on growth of Fraxinus mandshurica.The results showed that double strains afforestation growth is better than that of the Individual plant 5 years old Fraxinus mandschurica.Both the diameter growth and the height growth were well, and the best afforestation density was 2 m×1.5 m.
