Research on forest structure characteristics and natural rengeneration of natural forests on sandy soil (sandy forest) in Trieu Phong district, Quang Tri province

Abstract

Results of research on forest structure characteristics and natural
regeneration on sandy forests in Trieu Phong district, Quang Tri province
show that: the density of high tree layer is from 320-740 trees per ha, with
an average diameter of 6.8 -10.6 cm, and average height is 3.9-6.6m. The
number of tree species involved in the forest plant communities in research
area ranged from 4 to 11 species. In three studied communes, there are
typical tree species such as Syzygium corticosum, Memecylon edule,
Carallia brachiata, Scolopia spinosa, Syzygium zeylanicum that are the tree
with high ecological value in the forest restoration process, with the role of
a pioneer tree to create and restore forest conditions according to the
natural rule to a higher level. Almost the dominant trees of regeneration
tree layer are the dominant trees in the high tree layer such as Syzygium
corticosum, Syzygium zeylanicum, Scolopia spinosa. The density of regeneration trees in the study area is quite high, ranging from 10,586 to
16,773 trees per ha with 36.4% prospective regeneration trees. The height
of the regeneration tree layer is divided into 4 classes, in which the number
of regeneration trees at the height class under 0.5m is largest proportion
(over 40%). Seed regeneration rate is approximate 75.9% and shoot
regeneration rate is approximate 24.1%. The quality regeneration trees in
the study area is mainly average quality, accounting from 54.0 - 67.8%,
good quality regeneration tree is from 23.6 - 37.2%, and the bad
regeneration tree is from 8.5 - 12.4%.