SILVICULTURE CHARACTERISTIC OF Aquilaria yunnanensis S.C.Huang IN BAC NINH AND QUANG NINH PROVINCES

Abstract

Aquilaria yunnanensis S. C.Huang belong to Aquilaria is one of the species that can produce high-quality agarwood. In order to contribute to providing a scientific basis for the conservation of A. yunnanensis, the study was conducted to assess the distribution status and ecological characteristics of A. yunnanensis in Son Dong district, Bac Giang province (Bac Ninh province now) and Ha Long city, Quang Ninh province. The study investigated 6 transect lines and 6 sampling plots (1.000 m²) to determine the natural distribution area and ecological characteristics of the forest where this species distributed. The study also determined the soil characteristics, physical and chemical properties of the soil in two areas where A. yunnanensis is distributed. The results identified 61 individuals in Ha Long city, Quang Ninh province distributed at altitudes of 133 - 430 m and 12 individuals in district Son Dong, Bac Giang province at altitudes of 421 - 649 m. The total of 73 individuals included both mature and regenerated trees. Regarding forest ecological characteristics, the composition of tree species in the sampling plots has the number of 12 - 24 species, and a regeneration of trees ranging from 10 - 21 species. The dominant tree species participating in the composition of the standing tree layer range from 4 - 8 species, and the regeneration of trees range from 4 - 5 species. In the stading tree layer and the regenerated tree layer, A. yunnanensis appears in the composition of the sampling plots investigated in Quang Ninh province. A. yunnanensis is distributed in the areas where the soils with mechanical composition from medium clay to heavy loam and pH from very acidic to acidic, on mountain slopes with high slopes from 10 - 25º.