Information on Forest Science and Technology
Number 4 2005
Summaries of papers in the bulletin; for more information contact info@fsiv.org.vn
1. Results of establishing production plantation models in Ha Giang (Hai)
Studies were carried out from 2002 to 2005 as part of a project to develop economical effective and stable production forest plantations in the northern mountainous area of Vietnam. This was part of a larger research program serving the development of the region. The results are the establishment of a 21 ha production forest plantation model of which 8.5 ha is for the supply of large logs, 5.5 ha is for the supply of small logs and 7.0 ha is for the supply of non-timber forest products. Initial evaluation shows that the trees in the model all have high rates of survival and growth, and thequality is high. From a social viewpoint, the model has been effective and brought practical benefits.
2. Result of forest rehabilitation after shifting cultivation in an area of Ben EnNational Park (Nghi)
The report shows the results of a general study on succession in forest sere after shifting cultivation in the period 1997-2003 including the change of vegetation cover over time. The report also estimated time required for the rehabilitation and described the influence ofvegetation, soil and microclimate on rehabilitation.
3. Growth characteristics, rhizocorm development and cutting propagation of Phyllostachys pubescens Mazel Ex de Lehaie (DM Hung)
The author studied the growth and development characteristics of Phyllostachys pubescens Mazel Ex de Lehaie, rhizocorm development and vegetative propagation in order to create a base for high production and sustainable management of Phyllostachys pubescens forests. The article showed the results of trials of cuttings at the age of 2 years, of stem sections of 4—6 internodes and 2-year-old rhizocorm cuttings of 4 internodes, all treated with growth promoting substance ABT1 at100ppm. .
4. Results of isolation of vesicular arbuscular mycorrhiza with indigenous tree species for timber (Yen)
The author has isolated the vesicular mycorrhiza and has obtained some specific results such as: assessment of vesicular arbuscular mycorrhiza, and some characters to recognize the 2 genera of mycorrhiza and spore density of each genus in 100 gm of soil. Apart from its usefulnessto the tree, the vesicular arbuscular mycorrhiza also has the effect ofa great reduction in disease infection of the roots caused by fungus, epiphysis and virus.
5. Results of estabishing economically effective land use models and prevention of damage to vulnerable areas of Song Da riverside (Trieu)
Sustainable land use models have been established from watershed at vulnerable areas ofshoreline of Song Da river at Tan Phong commune, Phu Yen district, Son La province. After 3 years of application, the study has generated some initial socio-economic and environmental results. These results will form the basis to spread information within the region in order to improve living conditions of residents and to contribute to the protection of the shoreline of Da River from erosion.
6. Orient to build subdivision system of submerged soil in Vietnam (Thinh)
The article investigated the international classification system for wetland soils and proposed a system suitable for Vietnam. This classification systemhas been used for land mapping and wetland management in Vietnam.
7. Research on the impact of organic fertilizer and micro-organic fertilizer on Acacia hybrids growing in the first rotation on forest land in Tan Lap, Binh Phuoc province (PT Dung)
The article studies the use of organic fertilizer, micro-organic fertilizer and addition of DAP mineral manure, studied in container experiments in Dong Phu district, Binh Phuoc province. The study results show that most of the fertilizers gave better height and diameter growth of hybrid acacia than non-fertilizer treatments. Song Gianh micro-organic fertilizerwith additional DAP gave the best growth.
8. Testing the use of mica tube for Pinus hybridization (Chi)
The percentage of cones that survived after removal of PBS pollination bags was 80% for Me23Ca44 to 98% for Me8Ca44 but while covered with mica tubes the percentages of survival were 100% for all crosses. The percentage of cones that survived when using the mica tube was 79.6% for Me8Ca15 and Me23Ca20 while using the PBS bag it was 49.7% and 47.3%. The lowest percentage survival was 44.3% for the mica tube (Me13Ca20) but that was higher than using the PBS bag (38%). In general, when comparing each hybrid combination the cone survival rates were higher with the mica tube than with the PBS bag. The authors conclude that mica tubes should be used as the isolation material for production of Pinus hybrids as the number of cones produced each year will be higher and the price is cheaper than the PBS bag.
9.Protection effects of plantation on coastal sand dunes (DV Thuyet)
Results of research and development of protection forests of Casuarina, A. difficilis, A. torulosa, and A. tumida on coastal sand dunes in Quang Binh have shown that: 3-year-old forest belts of A.difficilis and A. torulosa can survive and grow well in dense stands. Casuarina and A. tumida can also grow on the sand dunes but with smaller, more open canopies. Thus, forest shelter belts of A.difficilis and A. torulosa can perform well as wind breaks, and for sand stabilization, air temperature and moisture improvement, soil chemical improvement and returning more biomass to the soil, and are superior to Casuarina and A.tumida .
