Vietnam Journal of Forest Science Number 3-2013

Results on trial of newly approved eucalyptus clones in Hoa Binh and Thanh Hoa

In recent years, dozens of fast-growing Eucalyptus clones were approved by Ministry of Agricuture and Rural Development as new advanced-technological varieties. However, only some of those clones were planted in a large scale, such as U6 and PN14. In order to put newly approved varieties into large-scale planting, trials of these varieties in major ecological regions of Vietnam should be conducted. Trials of new advanced-technological Eucalyptus clones was built in 2010 in Truong Son, Luong Son, Hoa Binh and Luong Son, Thuong Xuan, Thanh Hoa. After three years, clones PN10 and PN108 achieved a Mean Annual Increment (MAI) of more than 20 m3/ha/yr in trial in Thanh Hoa. Meanwhile, six clones (PN10, PN46, PN47, PN46, PN108 and PN14) in trial in Hoa Binh had a MAI of more than 20 m3/ha/yr, especially clone PN108 had highest MAI (31.2m3/ha/yr). Leaf diseases occurrence in all trials but with low damage incidence and it has no impact on tree growth.



The effects of shading and composition of container medium on the survival and growth of Michelia tonkinensis A.chev seedlings

Michelia tonkinensis A.Chev is multiple-purpose and high value tree species in Vietnam. This research evaluated the effects of shading regime and compositions of container medium on survival rate and growth of the seedlings. The experiment was designed by a method of randomized complete block with 3 replications for two separate factors: shading with 5 levels (control, 25%, 50%, 75% and 100%) and the 5 different compositions of container medium. The result showed that shading had significant effect on survival rate (%), the collar diameter (Do), and top height (Hvn) of the seedlings and varied with the age of seedlings in nursery. The optimum shading level was at 75% in the period of 4 months, and at 50% in the period of 6 to 8 months. The factor composition of the container medium in this research had no significant influence on the survival rate of the seedlings, but significantly affected on the collar diameter and height of the seedling. The best medium composition was made of 95% of top soil and 5% of mixed humus and microorganism fertilizer in terms of container volume percentage.


Assessment of growth and disease index of new acacia hybrid and acacia auriculiformis clones approved in recent years

In recent years, a number of fast-growing Acacia clones was approved by Ministry of Agricuture and Rural Development as new advanced-technological clones. However, approval of these new clones was based on clonal tests established in one or several ecological zones with small scale and only some of these clones were planted in large scale. In order to put new varieties into large-scale planting, planting trials of these varietes in major ecological regions of Vietnam should be established. Trials of new Acacia clones were conducted in 2010 and 2011 in 5 ecological regions. After two years in Ca Mau and three years in Yen Bai, two Acacia auriculifomis clones AA1 and AA9 achieved a Mean Annual Increment (MAI) of more than 20 m3/ha/yr. For Acacia hybrids, two clones coded AH1 and AH7 had a MAI of more than 25 m3/ha/yr in trial in Ca Mau and Thanh Hoa, while clone KL2 (two years old) achieved a MAI of 22.3 m3/ha/yr. In all trials, pink disease caused by Corticium salmonicolor and leaf wilted disease caused by Ceratocytis sp. were not found, while leaf spots and twig died-back were found on A26 and AA15 A. auriculifomis clones and TB1, TB11 and TB12 hybrid clones. Hybrid clones AH1 and AH7 as well as A. auriculifomis clones AA1 and AA9 showed great potential in growth performance and disease resistance.


Evaluated possibility to drought-resistant and growth of Taxus wallichiana Zucc and Pinus caribaea Morelet in nursery phase additional super absorbent polymer manufactured by radiation technology

This study aimed to evaluate possibility of the super absorbent polymer (SAP) to drought-resistant and growth of Taxus wallichiana Zucc and Pinus caribaea Morelet in nursery phase. The result indicated that with concentrations: 0, 0.2, 0.5, 0.7, 1.0% SAP for Taxus wallichiana Zucc and 0, 0.1, 0. 2, 0.5, 0.7% SAP for Pinus caribaea Morelet, the life period of trees is directly proportional to SAP added. The growth experiments, suitable concentration when non-irrigated and irrigated for 12-month-old Taxus wallichiana Zucc trees is 0.5% SAP with the highest shoot amounts and the shoot length (Shoot amounts: 8.8 and 19.1; shoot length: 3.99cm and 9.32cm); And 6-month-old Pinus caribaea Morelet trees is 0.2% SAP with the highest length of new shoots (0.39cm and 3.01cm).


The study composition and distribution of mangrove as a basis for selecting species to plant on the sand, stone, coral in Con Dao island of the south Vietnam

The study on composition and distribution of mangroves in Con Dao island were carried out to identify the composition and structure of mangroves on sandy, gravel and coral reef and particle conditions. The research results were considered as scientific basis to select efficient mangrove species for developing mangrove forests along coastal lines and islands in the South Vietnam. Results indicated that mangrove species are distributed in seven different islands belonging Con Dao district. There were 33 species belonging 20 families, of which 24 species belonging 11 families are true mangrove groups and 9 species of 9 other families were identified as their associates. The author selected and proposed Rhizophora stylosa, R.apiculata, R.mucronata, Aegiceras floridum, Ceriops tagal for developing mangrove forest in costal lines and islands in the South Vietnam.


Plant characteristics of Magrove at Dong Long commune, Tien Hai district, Thai Binh province

The Mangrove forest natural area at Dong Long commune, Tien Hai district, Thai Binh province is almost the planted forests. The diversity of species compositions is high; the flora of mangrove forests has 66 species belongs to 33 families distributed following 7 community groups. Nevertheless, the plant communities at natural forests showed the most development with 8 species of tracheophyta in two plant assemblages of Trang (Kandelia obovata) – O ro (Acanthus ebrateatus) and Co ngan (Scirpus kimsonensis) – Co cay (Sporobolus virgicicus). The relationships between species of natural forest were highest with the most stable structure of the forest, and the best growth of treescomparated with other mangrove ecology systems. In the reservoirs of aquaculture, the mangrove flora developed towards the degenerated successions with 11 species of two plant assemblages of Trang – Su (Aegiceras cornicudatum) and O ro – Say (Phragmites karka); or only included one assemblage as Trang – Ban (Sonneratia caseolaris) combined with8 species in a mixed plantations of Trang and Ban; or Trang combined with three other species on the mono plantation of Trang on the alluvial ground.


Evaluating the potential land for growing of Amomum longiligulare in forest garden in yen bai commune Ba Vi district, Ha Noi city

The research site was conducted in Yen Bai commune, Ba Vi district, Ha Noi in order to evaluate the potential land for growing of Amomum longiligulare in forest garden. The research results indicate that the bulk density is in the range of 1.127 to 1.284 g/cm3, finding out the soil of research site is quite closely; the soil moisture is in the range of 23.11 to 27.65%. The soil texture is from light to medium loam (the content of clay particles is from 24.08 to 27.06%). Soil is strong acid, PHKCl from 4.0 to 4.06. The soil properties are good for growing such as medium levels of total nitrogen content, from 0.12 to 0.19%; rich total of P2O5, from 0.15 to 0.2%; rich total of K2O, from 0.63 to 0.71%; very poor to poor levels of digestible nitrogen, from 1.759 to 2.752 mg/100g; plenty of digestible P2O5, from 8.727 to 11.567 mg/100g; much abundace of digestible K2O, from 82.3 to 170.12 mg/100g. Overall, the soil propertities are suitable for growing Amomum longiligulare. However, when growing Amomum longiligulare, note that comprehensive land preparation, organic fertilizer addition to increase soil porosity, pouring fresh water or choosing an appropriate growing season to increase the soil moisture, lime addition to reduce the soil acidity and the suitable nitrogen fertilizer addition to increase the disgetible nitrogen content.


Assessing the site condition potential of Binh Phuoc province

Assessing the site condition potential is one of the most important techniques for providing sound scientific and practical bases for sustainable land use planning. Using the programming technology, the site condition database grids and a technique of spatial analysis based on the Global Information Systems, this research have successfully fulfilled (i) determination of the grading system for the criteria, norms in classifying the site conditions; (ii) quantification of the potential of each site pixel (each square grid cell); (iii) gradation of the site condition potential for each grid cell; (iv) establishment a map of the site condition potential zones of Binh Phuoc province. The results of this research revealed that Binh Phuoc province has 174,298.02 ha of forestry land, in which: 77,141.75 ha (44.26% of total natural land) belong to the site potential level 1; 81,028.08 ha (46,49% oftotal natural land) belong to the site potential level 2; 15,404.19 ha (8,84% of total natural land) belong to the site potential level 3; 724 ha (0,24% oftotal natural land) belong to the site potential level 4. These results are very meaningful and directly contribute to improve the land use management in the local scales for Binh Phuoc province.


Nutrients of litter-fall and haevesting residue of Dendrocalamus babartus plantations in Thanh Hoa province

The experiments were established in order to estimate the nutrients of litter-fall and residual after harvesting of Dendrocalamus barbatus Hsueh et D. Z.Li plantations in Thanh Hoa province during 2010-2012. Results showed that the litter-fall ranged from 3,195 to 4,083kg/ha/year and harvesting residue were from 1,980 to 3,013kg/ha/year, depending on the location. The total nutrient of four elements from litter-fall and harvesting residue of the Dendrocalamus including nitrogen (45.67kg/ha/year); phosphorus (9.68kg/ha/year); potassium (28.56kg/ha/year) and cancium (22.63kg/ha/year).


A review of the generic taxonomy of the genus gigantochloa, oxytenanthera and pseudoxytenanthera from vietnam


The genus Gigantochloa Kurz ex Munro, Oxytenanthera Munro and Pseudoxytenanthera Soderstrom & Ellis from Vietnam are thoroughly studied and revised. Based on collected specimens, specimens in some herbaria, compared with the major modern systems of classification of the wood bamboos, the authors suggests that Gigantochloa should include Oxytenanthera, Pseudoxytenanthera. We also suggested the diagnostic characters were mid-culm branch complement with a dominant primary branch and several small secondary branches, 1-5 perfect flowers, an imperfect or not an imperfect terminal floret, palea 2-keeled or convex, filaments always fused into a tube. And based on the structure of the pseudospikelets which are a perfect terminal floret and an imperfect terminal floret, two subgenera, subgen. Heterofloreta and Monofloreta were established.


Status of the endangered wildlife species of Phu Canh nature reserve, Hoa Binh province

 Phu Canh nature reserve is located in Da Bac district, Hoa Binh province. Although the reserve only covers an small area of ​​5,644 ha, it plays an important role in the conservation of biodiversity resources and supports many rare wildlife species that have high conservation value in terms. During a survey from September to October 2012, a total of 27 mammal species in 14 families, 4 oders, 60 bird species in 23 families, 6 orders, 22 reptile species in 10 families, 2 orders, and 14 amphibian species in 6 families, 1 order were recorded. The number of species recorded during the survey is much higher than the previous preliminary investigation. Many species are rare and endangered and listed in the Vietnam Red Book, IUCN Red List and Decree 32/2006/ND-CP. However, the populations of those endangered species such as Asiatic black bear (Ursus thibetanus), mainland serow (Capricornis milneedwardsii) contain few individuals. Some animal species have become locally extinct in recent years. This suggests that if conservation efforts are not implemented soon, the populationss of the endangered wildlife species residing in protected areas may decline rapidly.


Diets of asiatic brush-tailed porcupines (Atherurus macrourus Linnaeus, 1758) in captivity

Asiatic brush-tailed porcupines (Atherurus macrourus Linnaeus, 1758) is wildlife species that provides delicious meat and is preferred foods on the market. However, most Asiatic brush-tailed porcupines sold on the market are harvested from natural environment. In Vietnam, farming of the species has not brought high economic efficiency because the understanding of it’s biology and ecology is limited. In this study, 08 Asiatic brush-tailed porcupines were fed with a variety of foods in captive condition. The study results show that Asiatic brush-tailed porcupines uses 73 types of food, including 26 favorite foods. The species do not eat food that has special odors or contain alot of fiber. The amount of food needed for an individual/day is around 400g, deviding into: 170g vegetables + 80g bulb + 90g fruit + 100g grain. The study results provide additional information on the ecology of the species and improve farming techniques for Asiatic brush-tailed porcupines.


Studying for the checklist of satyridae in Bach Ma National park, Thua Thien Hue      

By field surrvey methods combined with legacy documentation, this study has defined 56 species that belong to 11 genus of Satyridae. Of which, the Lethe and Mycalesis genera have the most of number species (16 species) and Coelites, Orinoma, Orsotriaena, Penthema and Zipaetis genera have the least of number species (1 species). This study also has supplemented 5 genera and 28 species for the checklist of Satyridae in Bach Ma National Park. So the number of genus and species was recorded in reality of this study is higher than previous studies. Exceptional, this study have recorded a butterfly is endemic in Vietnam and noted the distribution of two new species of Satyridae. It is necessary to study on biodiversity and similarity of Satyridae between some area, so it is the basis of conserve method in Bach Ma National Park.


Status and research results in planting native plants, Vietnam

This paper summarizes 40 years of research and use of native species for plantations in 8 regions of forestry ecological economics on a national scale. Based on the basis analysis: Decision No. 680 QD / LN dated 15/08/1986 of the Ministry of Forestry (old), Forestry Handbook 2006, The 661 project during (1998-2005) and Decision No. 16/2005 – BNN dated 15/03/2005 of Ministry of Agriculture and Rural Development, the research was statistics and classification of preliminary nearly 100 species, including 30 species of exotic trees, including broadleaf trees, conifers, bamboo, rattan and climber trees. It could be the first assessment to evaluate objectives of diversity of species and forestry products in plantations. Since then, research results have shown the limitations, such as: Only 18 species have the technical regulations in plantations in 22 tree species are growing in popularity with thousands of hectars; Too many species, large orchestra, but lack of focus for the key species; and most species are determined based primarily on the basis of experience, so that, there is a lack of qualitative research results depth to build technical guide in system. Notably, there are not experimentations on different areas and stratrum sites as well as technical advances delivered in a timely manner and not a primary focus for some key species for high-value forest products, particularly for export.

It is suggested that the further studies should be done to make complete and systematic solutions in depth for 4-5 major tree species native broadleaf highest value: Michelia mediocris, Chukrasia tabularis, Dipterocarpus alatus, Hopea odorata, Lithocarpus fissus. Plantations should be linked to processing and market-oriented production forests at smallholder scale to attract households participated in.


Assessment the bonding levels of Eucalyptus camaldulensis by using synteko 1985 (EPI 1985/1993)

The bonding properties of Eucalyptus camaldulensis 14 year old in Dai Lai with popular wood adhesive Emulsion Polymer Isocyanate (EPI 1985/1993) were experimented in two conditions including dry and wet environments. The results of bonding strength test were good and exceed those of Acacia and Meliaceae species with the former being over 14 MPa, the later being 11 MPa and 10 MPa, repectively. Although the bonding levels of treated samples were smaller than those of untreated samples, this deviance is insignificant at approximately 4 MPa. In addition, the difference between dry and wet conditions was also a little. This was shown that as using EPI 1985/1993 adhesive in bonding of Eucalyptus camaldulensis wood component bars ensured the required quality, even if in the E environment has the impacts of water immersion and drying process.


Research on bending technique of Pinus merkussi Jungh et de Vriese for munufacturing funiture on UG – HĐ wood bending machine

Wood bending technology to manufacture bentwood for furniture in order to improve product quality and rate of using wood was research and application in many countries such as Japan, Russia, the U.S. and China. Research on Pinus merkussi bending technology to manufacture bentwood for furniture is implemented and obtained some results: (1) Indentified the speed of bending in accordance with 03 wood thickness level as follows: thickness of bentwood 20mm, bending velocity is 26.5mm/s; thickness of bentwood 25mm, bending velocity is 17.7mm/s; thickness of bentwood 30mm, bending velocity is 17.7mm/s. (2) Indentified wood bending elasticity at 03 levels thickness, wood bending elasticity limits allowed Df <3mm. (3) Indentified the properties of the bentwood: density; ratio of volumetric swelling, compressive strength parallel to grain. Quality of bentwood is activited to requiring of tecnhology parameter.


Study on the effect of ratio polypropylene, chemical coupling agent, wood flour on the tensile strength and flexural strength of wood plastic composite

The quality of wood plastic composite material is shown through factors such as tensile strength, flexural strength,… These factors have intimate relationships with technological parameters of composition ratio. The study determines the optimization of composition ratio parameters in the production process allowing to reduced price of production and improve the quality of the product. The results were shown that the value of tensile strength and flexural strength were depended on the rate of composition of polypropylen, chemical coupling agent and wood fiber. A quadratic equation was established and solved to determine the optimization of rate of compositions. Polypropylen is 50.4%; Chemical coupling agents is 4.04%; Wood flour is 45.56% with these compositions, the wood plastic composit will has the best results of the tensile strength and flexural strength.


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