Vietnam Journal of Forest Science Number 1-2016

TÓM TẮT Kết quả nghiên cứu thực trạng tái sinh tự nhiên trong điều kiện tự nhiên và gây trồng tại Lào Cai, Yên Bái, Hòa Bình và Xuân Mai (Hà Nội) cho thấy, Đinh đũa là loài cây bản địa có khả năng tái sinh hạt và cả tái sinh chồi khá mạnh. Trong điều kiện gây trồng khả năng tái sinh tự nhiên của loài Đinh đũa diễn ra mạnh mẽ, trong khi ở rừng tự nhiên chưa phát hiện thấy tái sinh tự nhiên xuất hiện, và tái sinh tự nhiên xuất hiện hạn chế ở khu cây trồng phân tán. Trong điều kiện đất ẩm mát dưới gốc cây mẹ sai quả ổn định, số lượng cây tái sinh nhiều, chất lượng cây tái sinh tốt hơn so với điều kiện dưới gốc cây mẹ lớp đất mặt khô cằn, lẫn nhiều sỏi đá. Trong điều kiện gây trồng, khả năng tái sinh tự nhiên diễn ra khá mạnh mẽ dưới gốc các cây Đinh đũa sai quả, có tuổi trên 15 năm. Thành công của nghiên cứu này góp phần quan trọng cung cấp thông tin, cơ sở xúc tiến tái sinh tự nhiên cho loài Đinh đũa trong điều kiện tự nhiên và gây trồng, góp phần quan trọng cho chọn giống, bảo tồn và phát triển tại các địa điểm nghiên cứu và các nơi khác có điều kiện tương tự.

Từ khóa: Cây bản địa, tái sinh tự nhiên, Đinh đũa, đặc điểm sinh trưởng

The research results of the evaluate reality of natural regeneration of Yellow snake trees under the netural forest canopy and plantation in Lao Cai, Yen Bai, Hoa Binh and Xuan Mai (Hanoi) shows, it is based indigenous species capable of regeneration seeds and buds sharply regeneration. In terms of planted natural regeneration capacity of Yellow snake tree to bring strong, while in terms of natural forest regeneration undiscovered natural trees and plants scattered natural regeneration capacity appears limited. In the moist soil conditions under a mother tree fruitings stablity many years, the number of trees regeneration more and better quality than the arid soil or gravel. In terms of plantation, natural regeneration going strong at the base of mother tree fruiting stability, aged over 15 years. The success of this study provide an important contribution to information, promotion of natural regeneration in natural conditions and plantation, contribution to the breeding, conservation and development Yellow snake tree in the study sites and elsewhere have similar conditions.

Keywords: Native plants, natural regeneration, Stereospermum colais, growth characteristics

Từ khóa: Mối quan hệ, Xoan nhừ

 Research on relationship between Choerospondias axillaris and other species in natural forests, used survey methods of “6 tree plot” and appearing frequency index. The results showed that: Choerospondias axillaris distribution in evergreen broadleaf forest, spartly; on the upper storey of the forest canopy, DBH and Ht are higher than that of neighbour species; In Van Ban, there were 49 species living with Choerospondias axillaris; In Sa Pa, there were 50 species living with Choerospondias axillaris; In Moc Chau, there were 26 species living with Choerospondias axillaris; In Phu Yen, there were 20 species living with Choerospondias axillaris; In Thuan Chau, there were 24 species living with Choerospondias axillaris; In Lao Cai, the number of species appearing with A. triphysa with very high frequence were Canarium album; In Son La, The number of species appearing with A. triphysa with very high frequence were Ficus religiosa, Lithocarpus fissus, Eberhardtia aurata, Choerospondias axillaris.

Keywords: Relation, Choerospondias axillaris

Từ khóa: Cấu trúc rừng, Dẻ gai phú thọ, mối quan hệ loài

Castanopsis phuthoensis Luong is an endemic tree species of Phu Tho province, only distributed narrowly in forest rehabilitation in two communes belonging to Doan Hung district. As it is difficult to find the seedling in the nature, research on forest structure and relations between tree species is very necessary to define method of conservation for this species. The species is dominant tree species in the forest rehabilitation with both IV% indexes and percent of each species for number of trees above 5% in nature regeneration forest and enrichmnet forest by additionally planting in holes in the forest, particularly nearly 10% in nature regeneration forest with high and medium density, and reaching 14.5% in enrichmnet forest by additionally planting in the holes, density of this species is very low, only from 3.1 to 11.1 trees per hectare. Diameter distributions of the species of number of trees is characterized by curve style with a peak in 20cm or 24cm diameter classes. Its height distributions are also curve style with a top in 18m or 20m heigh classes. This peaks are higher than diamter and heigh average of the rehabilitation forest. Both the diameter and heigh distributions are not suitable to Meyer, Weibull and Interrupted distribution. This species occurs itself and 31 other tree species, clearly grows in population, and often appears six other native tree species, including Ormosia balansae, Erythrophloeum fordii, Castanopsis cerebrina, Quercus platycalyx, Gironniera subaequalis and Garcinia oblongifolia.

Keywords: Forest structure, Castanopsis phuthoensis, relations between tree species

Từ khóa: Cây bản địa, Cầu Hai, Phú Thọ, sinh trưởng, gỗ lớn, rừng trồng hỗn loài

Mixed plantation experiments by native species for timber at the Forest Science Centre for Central of North Vietnam in Cau Hai, Phu Tho province was established in 2001 on degraded forest land with different types of nurse trees such as Tephrosia candida and Acacia mangium. Measurement data in 2014 showed that, after 14 years of planting Cinnamomum obtusifolium and Lithocarpus fissus species in the experiments reached 86.5 to 87.8% survival rate, they have good growth and development. Some Lithocarpus fissus trees was able to supply timber (DBH over 30 cm), while the Canarium album and Endospermum chinensis species have a low survival rate (from 61.1 to 66.5%) and poor growth and development. At age of 14, the growth of Lithocarpus fissus species has D1.3 = 21cm, Hvn = 14.2m, Dt = 5.9m; Cinnamomum obtusifolium species reached D1.3 = 13.3cm, Hvn = 11m, Dt = 3.7m; Endospermum chinensis species has D1.3 = 8.6cm, Hvn = 8.8m, Dt = 2.7m white Canarium album speices reached only D1.3 = 7cm only, Hvn = 7.5 cm and Dt = 2.2m. The average yield of native species in the models ranged from 69.4 – 94.7 m3/ha (average is 86 m3/ha), the average increment from 5.4 – 6.7 m3/ha/year (average is 6.1 m3/ha/year). Quality trees (including the small branches, stem straightness and development canopy) of Lithocarpus fissus and Cinnamomum obtusifolium species are good while Canarium album and Endospermum chinensis species are bad due to competed by other species in the experiments, especially in the experiment of nurse tree of Acacia mangium not been thinning at the age of 14 yet. Lithocarpus fissus and Cinnamomum obtusifolium species growth best in experiment of nurse tree is Acacia mangium.

Keywords: Cau Hai, Phu Tho province, mixed plantations, native tree, timber, growth

Từ khóa: Gỗ lớn, Keo lai (Acacia hybrid), Keo tai tượng (A. mangium), Keo lá tràm (A. auriculiformis), Bình Định, Phú Yên

If requirement of diameter at breast height (DBH) for sawlog is greater than 18 cm, almost Acacia hybrid plantation within 6 – 10 year – old in Binh Dinh and Phu Yen province cannot meet this requirement; DBH, standing volume and MAI of the poorest and fastes growth rate plantations were 9.18 and 16.67 cm, 57.96 and 133.51 m3/ha, and 9.06 and 19.07 m3/ha/year, respectively. For Acacia mangium, there are only two plantations which were 10 year – old in Binh Dinh province having DBH, standing volume and MAI of 23.38 cm, 231.88 m3/ha and 23.19 m3/ha/year, respectively. There was a 20 year – old plantation in Phu Yen province which had DBH, standing volume and MAI of 35.63 cm, 305.03 m3/ha and 15.25 m3/ha/year, respectively. For Acacia auriculiformis, there were four single – species plantations (pure A. auriculiformis) and a mixed – species plantation (A. auriculiformis + Hopea odorata); one of them was 14 year – old and the others were 20 – 21 year – old. However, only one 20 year – old single – species plantation and the 21 year – old mixed – species plantation which have timber that can be used for sawlog; DBH, standing volume and MAI of 21.39 and 24.99 cm, 198.27 and 224.89 m3/ha and 9.44 and 11.24 m3/ha/year, respectively. DBH, standing volume and MAI of the other plantations were 14.61 – 16.85 cm, 93.36 – 156.06 m3/ha, and 6.67 – 7.43 m3/ha/year. DBH growth in almost plantation were low. Further intervention by silviculture techniques should be applied, so timber of these plantations can be used for sawlog in the next 5 – 7 years.

Keywords: Sawlog, Acacia hybrid, Acacia mangium, Acacia auriculiformis, Binh Dinh and Phu Yen

Từ khóa: Biến động rừng, rừng ngập mặn ven biển, sử dụng đất, viễn thám, hệ thống thông tin địa lý

 Using multispectral Landsat images to monitor the changes in coastal mangroves indicates that the accurracy of classified images is more than 83%, this result therefore has reconfirmed that using Landsat images for quantifying changes in coastal mangroves is suitable and appropriate as they are freely available. The study shows that the extents of coastal mangroves have increased from 1994 to 2015, estimated at 523.2ha, in particular during the periods of 2003 – 2008 and 2010 – 2015, the extents of coastal mangroves have increased by 824.4ha (equivalent to 34.2%) and 910.8ha (equivalent to 34.6%). However, increased areas are mainly mangrove plantation with low quality as a result of mangrove plantation; mangrove rehabilitation and restoration programs from both international and national projects, namely Red Cross, ACMANG from Japan. Based on the findings, the paper suggests possible solutions for enhancing mangrove development and protection in study areas, namely enhancement of management schemes, suitable mangrove plantation approaches, socioeconomic and technical measures.

Keywords: Coastal mangroves, GIS, land use, mangrove changes, remote sensing.

Từ khóa: Nội sinh nhân tạo, Beauveria bassiana, Eucalyptus camaldulensis, Leptocybe invasa

The fungus Beauveria bassiana is a common fungal parasite of many arthropod species. The entomopathogenic properties of B. bassiana are well-known and it is used widely in biological control strategies in agriculture and forestry. Some strains of the fungus are mass-produced as commercial biological insecticides in many countries. This fungus can live as a natural endophyte in various plant species. Some studies have shown that B. bassiana can survive as an artificial endophyte in several plants. Its mycelium can infect, colonize and survive in plant tissues after artificial inoculation. Until now, B. bassiana has been reported only as an artificial endophyte of maize, potato, tomato, cocoa, cotton, wheat and banana. Therefore, the aim of this study is to experiment B. bassiana as an artificical endophyte of Eucalyptus camaldulensis for the control of the gall wasp Leptocybe invasa. We established artificial inoculation of the fungus as an endophyte in E. camaldulensis seedlings using two methods: (1) geminated seeds were drenched with conidial solution with a concentration of 108 CFU/ml of B. bassiana, and (2) germinated seeds were grown in a fungal mat of B. bassiana for 7 days. Results showed that at 12 weeks post-inoculation, B. bassiana had colonized the leaves, shoots and stems of the seedlings, with 76.7% of seedlings colonized using the conidial solution on germinated seeds and 80.0% colonized using germinated seeds grown in fungal mats. Height of seedlings colonized with B. bassiana was increased by 33.2% compared to non-inoculated control seedlings. Damage index scored for L. invasa on colonized seedlings was reduced by 82.1% compared to control seedlings and the damage severity of the colonized seedlings was also low, in the other hand, the non-colonized control seedlings got high level of damage.

Keywords: Artificial endophyte, Beauveria bassiana, Eucalyptus camaldulensis, Leptocybe invasa.

Từ khóa: Bệnh chết héo, bẫy bào tử, Ceratocystis manginecans, Keo lá tràm, keo lai, Keo tai tượng

Keywords: Acacia auriculiformis, Acacia hybrids, Acacia mangium, Ceratocystis manginecans, spore trap, wilt disease

Từ khóa: Đặc điểm sinh học, nuôi cấy thuần khiết, Phellinus linteus, sinh trưởng của hệ sợi

Phellinus linteus is a well – known Oriental medicinal fungus with a variety of biological activities, especially anti – tumor activities. This material is now widely collected in nature and as such has become extinct. Studies on the biological characteristics in pure culture are needed and the results can be used for fruiting body cultivation. Studies on the biological characteristics of Phellinus linteus in pure culture were conducted with three kinds of nutrient media: PDA (potato dextrose agar), GYA (glucose and yeast extract) and PGA (potato glucose agar), six temperature treatments (10oC, 15oC, 20oC, 25oC, 30oC and 35oC), six relative humidity (RH) conditions (75%, 80%, 85%, 90%, 95% and 100%) and the time of havesting of mycelial mass production. The results showed that the fungal growth increment reached highest values when mycelia were cultivated in PDA (2.92 mm/day) and PGA (2.71 mm/day). Good growth of mycelia were recorded when cultures were cultivated in temperatures from 20 to 30oC and the best growth increment was in 25oC, at a rate of 2.34mm/day. Mycelia grew well at a relative humidity over 90% and achieved an optimal rate of growth at 95% RH, growing 3.68 mm/day. The time required for cultivation from mass mycelial production was approximately 26 days, achieving a mass of 19.2gm fresh mycelia per 100ml of media.

Keywords: Biological characteristics, mycelial growth, Phellinus linteus, pure culture

Từ khóa: Bạch đàn, hình thái, Leptocybe invasa, thiên địch

Leptocybe invasa belongs to family Eulophidae, order Hymenoptera. This species is currently causing damage to eucalyptus in many countries around the world and has been reported damaging eucalyptus in Ho Chi Minh City, Đong Nai and Binh Phuoc province of Vietnam since 2004, up to now they have damaged and distributed across nine eco – regions in Vietnam. In 2015, according to investigation data about L. invasa in Dong Trieu (Quang Ninh), Phu Ninh (Phu Tho) and Yen Binh (Yen Bai), 4 species natural enemies were collected, including one species (Oxyopes sp.) belongs to predator group and three species were parasitic predators including Quadrastichus mendeli; Aprostocetus sp. and Megastigmus sp. Among these species, Quadrastichus mendeli is a very popurlar parasite on L. invasa; Aprostocetus sp. is popular and two species Megastigmus sp. and Oxyopes sp. are less popular.

Keywords: Eucalyptus, morphology, Leptocybe invasa, natural enemies

Từ khóa: Biston suppressaria, hại lá, Keo tai tượng, Lim xanh, Sâu đo

The looper caterpillar, Biston suppressaria Guen. is a major defoliating pest in many countries. It belongs to the Family Geometridae, Order Lepidoptera. It is a destructive and major defoliating pest of Camellia sinensis, Eucalyptus spp., Hevea brasiliensis, Aleurities montana, Lagerstroemia indica, and several species of Fabaceae. Since 1963, in Vietnam, this pest has caused many outbreaks to Erythrophleum fordii in Lang Son, Quang Ninh, Phu Tho, Vinh Phuc, Thanh Hoa and Nghe An provinces. As the area of A. mangium plantations has increased across the country, the looper carterpillar B. suppressaria has adapted to using A. mangium leaves as a source of food. Since 2014, this looper caterpillar has caused its first outbreak on A. mangium plantations in Tien Yen and Ba Che districts, Quang Ninh province, causing heavy losses for the plantations. The incidence of damage was assessed at between 13.6 (September) to 53.8% (June) and the damage index ranged from 0.11 (December) to 2.18 (June). The adult moths are grey. The males are in general smaller than the females and are easily distinguished by the antennae, which are bipectinated. The wing span of the male is 40 – 50mm, whereas the female is larger at 60 – 70mm. The last instar are brownish – grey in colour and range in length from 50 – 62mm at the 5th instar. Pupae are blackish brown, 20 – 23mm in lenght, and approximately 9mm in wide.

Keywords: Acacia mangium, Biston suppressaria, defoliator, Erythrophleum fordii, looper caterpillar

Từ khóa: Keo tai tượng, keo lai, Pythium, Phytophthora, Phytopythium, tính gây bệnh

Phytophthora species are among the most destructive pathogens of agricultural crops and forests in the world. There are currently more than 80 and 120 described species of Phytophthora and Pythium (Pythiaceae) worldwide respectively, and the vast majority are plant pathogens. Laboratory analysis of 16 soil and diseased roots specimens from Acacia mangium and Acacia hybrid plantations and nurseries, resulted in the recovery and identification of 16 isolates belonging to 12 Pythiaceous species. Seven of these species are new records for Vietnam including: Pythium helicoides, Pythium dissotocum, Pythium vexans, Pythium cucurbitacearum, Pythium graminicola, Phytopythium helicoides and Phytophthora katsurae. Pathogenicity of the strains varied from very strong to weak based upon artificial inoculation testing. Strains VTN04 and VTN06 belonging to Pythium helicoides, strain VTN15 belonging to Pythium dissotocum and VTN24 of Phytopythium helicoides were very strongly pathogenic to Acacia mangium and Acacia hybrid. Strains VTN13 and VTN22 of Pythium graminicola, VTN20 of Pythium sp. and VTN09 of Phytophthora katsurae were weakly pathogenic to both Acacia mangium and Acacia hybrid.

Keywords: Acacia mangium, Acacia hybrid, pathogenicity, Phytophthora, Phytopythium, Pythium

Từ khóa: Bệnh hại, sâu hại, rừng trồng, loài hại chính

Surveillance of insect pests and diseases of 17 forest tree species including Acacia auriculiformis, Acacia hybrids, A. mangium, Casuarina equisetifolia, Cinnamomum cassia, Dendrocalamus barbatus, Diptercarpus alatus, Eucalyptus camaldulensis, Eucalyptus hybrids, Eucalyptus urophylla, Hevea brasilliensis, Hopea odorata, Pinus caribeae, Pinus kesyia, Pinus massoniana, Pinus merkusii, and Styrax tonkinensis was conducted across nine ecological zones in Vietnam from 2012 to 2015. Three hundred and twenty eight species of insect pests and one hundred and thirty two pathogens were identified. Two species Calonectria quiqueseptata and Bursaphelenchus kesiyae causing diseases of eucalypts and Pinus kesyia, respectively were new descriptions and 40 species of insect pests and pathogens were new reports for Vietnamese fauna and microflora. The survey listed a number of major pest and disease problems across the 17 tree species surveyed. Acacia plantations make up the biggest area with about 1.3 million ha and suffer serious problems with Ceratocystis wilt disease caused by Ceratocystis manginecans and the polyphagous shot hole borer Euwallacea fornicatus. The second biggest plantation area is eucalypts making up about 350,000ha. The main problems are gall wasp (Leptocybe invasa) causing galls on young shoots and ribs of the leaves and leaf blight disease caused by Calonectria quinqueseptata, and leaf spot disease caused by Cryptosporiopsis eucalypti. The third biggest plantation area is pine making up 300,00ha, two kinds of needle eating caterpillar Dendrolimus punctatus and Dasychira axutha are serious pests for pine plantations and cause large scale outbreaks every two or three years.

Keywords: Diseases, forest plantation, insect pests, major pests

TÍNH ĐA DẠNG VÀ GIÁ TRỊ BẢO TỒN KHU HỆ THÚ (Mammalia fauna) TẠI VƯỜN QUỐC GIA BA BỂ, TỈNH BẮC KẠN

Đồng Thanh Hải

Trường Đại học Lâm nghiệp

TÓM TẮT Vườn quốc gia Ba Bể là một trong bốn Vườn quốc gia ở nước ta được công nhận Di sản của ASEAN. Vườn có tính đa dạng cao về các hệ sinh thái rừng, và các loài động thực vật. Tuy nhiên, cho đến nay sự biến động về thành phần, số lượng loài, các mối đe dọa đối với loài và sinh cảnh ở đây chưa được cập nhật. Mục tiêu của nghiên cứu này là xác định tính đa dạng thành phần loài thú, đặc biệt sự có mặt của các loài thú, giá trị bảo tồn của loài và các mối đe dọa đến loài và sinh cảnh. Phương pháp phỏng vấn, điều tra theo tuyến, bẫy lồng, lưới mờ được sử dụng để thu thập số liệu. Kết quả điều tra ghi nhận được 66 loài thú thuộc 25 họ, 8 bộ. Trong đó, có 28 (chiếm 42,42% tổng số các loài ghi nhận được) loài thú được xác định quan trọng ưu tiên cho công tác bảo tồn. Săn bắt và phá hủy sinh cảnh là hai mối đe dọa chính đến khu hệ thú tại Vườn quốc gia. Bốn giải pháp chính nhằm nâng cao hiệu quả quản lý bảo tồn khu hệ thú bao gồm: Bảo vệ loài, sinh cảnh và giám sát, đánh giá các loài thú, nâng cao nhận thức và cải thiện sinh kế cho cộng đồng.

Từ khóa: Đa dạng, thành phần loài thú, giá trị bảo tồn, Ba Bể, Bắc Kạn

Ba Be National Park, one of 4 national parks in our country, has been recognized as ASEAN Heritage. The park has a high diversity of forest ecosystems, and the plant and animal species. However, there has been no update on the changes in composition, number of species, the threats to the species and habitats. The objectives of this study were to determine the diversity of species of mammals, especially in the presence of the mammals, the conservation values of the species and the threats to the species and habitats. Interviewing, linetrasects, traps, mist nets were used to to collect data in the field. The surveys were recorded 66 species of mammals belonging to 25 families, 8 orders. Of these, 28 (accounting for 42.42% of the recorded species), mammals were identified important priorities for conservation. Hunting and habitat destruction are the 2 major threats to the fauna of the national park. Four main solutions were recommended to improve the efficiency of conservation management of mammal species including species and habitat protection, mammal monitoring and evaluation, raising awareness and livelihood improvement for local communities.

Keywords: Diversity, species composition, conservation values, Ba Be, Bac Kan

Từ khóa: Axit hữu cơ, acetone, chất chiết xuất, chất trung tính, keo lai

This paper presents the results of the preliminary studies of extractives from leaves of Acacia hybrid. Some chemical compositions of the leaves have been identified, the method of extraction in petroleum ether and acetone has been applied, several methods for improving the extraction effectiveness were studied. After separation of the extractives dissolved in petroleum ether, some target products were quantified such as organic acids, neutral substances and sodium chlorophyll. Organic acids of up 0.61 to 1.82%, neutral substances of up 2.13 to 5.43 and sodium chlorophyll of up 0.16 to 0.23% of dry leaves weight were obtained. An UV – VIS spectrum of sodium chlorophyll wasused for identifying the preliminary composition of organic acids and neutral substances. Analysis of leaves powder extracted by petroleum ether showed that the crude fiber content and nutritional contents were comparable with some kind of animal feed additives, such as sweet potato leaves, soybean stems and banana stalks. The research results are the base for the further study of the utilization of natural products from acacia leaves.

Keywords: Acacia hybrid, extractives, neutral substances, organic acids

Từ khóa: Độ bền cơ học, gỗ keo lai, xử lý nhiệt

High temperature treatment is an environmentally friendly method suitable for improving the wood quality. However, in some cases, the mechanical properties of heat – treated wood are decreased For studying the impact of this method on acacia’s wood, In this study, the Acacia hybrid wood was treated in nitrogen gas under laboratory conditions for 2 – 6h at 210oC – 230oC. The mechanical properties of treated wood, including the modulus of rupture, modulus of elasticity and brittleness are tested in parallel with untreated samples The results of analysis showed that 3 factors including treatment temperature, treatment duration and wood parts (sapwood and heartwood) have significant effects on the modulus and brittlenessof high – temperature treated wood, howerver, these factors have no effect on the modulus of elasticity. The sresults also showed that these properties were reduced significantly by heat, but there is not effect of temperature and duration on them, excluding the brittleness.

Keywords: Acacia hybrid wood, thermal treatment, wood strength

Từ khóa: Chế độ cắt, đồ mộc, MDF, sai số vuông góc, vận tốc cắt, vận tốc đẩy

Determinative the appropriate cutting regime is a topical issue, a large requirement from processing practice of furniture manufacturing. This article introduces the results of a study to identify the regime cut MDF material on common equipment are disk saws Model P – 2800 TM. Results of experimental studies have identified the mathematical equations indicate the influence of the three basic parameters of the cut regime is the cut speed v, push speed u, width kerf saw blades r to the rectangular of a circuit split, is a important indicators parameters of the workpiece from MDF material for wooden products. From theoretical analysis and synthesis experimental results has established a set of parameters of reasonable cutting regime to cut MDF 20mm thickness on disk saws Model P – 2800TM, while ensuring high demand for rectangular for a cutting artery.

Keywords: Cutting regime, furniture, MDF, quadrature error, cutting speed, velocity push