A projected increase in stand volume of introduced provenances of Acacia mangium in seedling seed orchards in South Sumatra, Indonesia

Abstract

Increases in stand volume with some currently introduced provenances of Acacia mangium: Papua New Guinea (PNG) and Far North Queensland (FNQ), were projected based on their superiorities in 3-year height growth in seedling seed orchards using the growth model developed for unthinned plantation for pulp and paper production in South Sumatra, Indonesia. The height growth of these provenances was better than that of the local selections from Subanjeriji by 10%-15% at 3 years old and these percentage superiorities would be expected to remain at around 9%-14% until the 8-year rotation. This amount of increase would result in a 7%-10% increase in basal area and hence it would produce a 17%-26% increase in stand volume at rotation age when compared with the Subanjeriji seed source that was being widely used for the plantation establishment of A. mangium in Indonesia.

Effect of pruning Acacia mangium on growth, form and heart rot

“…This is a similar growth rate to that observed in this experiment. Subanjeriji Local Landrace also had a similar growth at age 3 years to that observed at the same age in a provenance trial in a different part of this forest estate in South Sumatra where provenances from Australia and PNG had significantly greater height growth (Nirsatmanto et al, 2003).…”

Growth model for predicting stand development of Acacia mangium in South Sumatra, Indonesia, using the reciprocal equation of size–density effect

“…The polymorphic site index curves used in this study were drawn from the two equations: guide curve (h 1 ) and standard deviation curve (h 2 ), and are shown in Table 2 (Nirsatmanto et al, 2003). This set of equations has been used widely in Japanese forestry to describe polymorphic site index curves (Nishizawa, 1972).…”

“…Growth and yield studies on A. mangium have been reported from several countries in tropical Asia (Inose et al, 1992;Latif et al, 1995;Forss et al, 1996;Nirsatmanto et al, 2003). However, all of the growth models used in these studies assumed a fixed stand density in each region and thus are insufficient to predict stand development under different density conditions such as different initial spacing and/or varying intensities of thinning.…”

A simple step-wise procedure for predicting stand development of Acacia mangium plantations based on the maximum size—density line in South Sumatra, Indonesia

“…Other independent variables examined for the multiple linear regression analysis were site index, which is the stand height at base age 8 years for each of the permanent plots (Nirsatmanto et al 2003), and quadratic mean diameter on a logarithmic scale. In the case of nonlinear regression, a Mitscherlich function was fitted to the trend of the rate of reduction in stand density to the increment in diameter (DN/DD) using the distance as an independent variable (X).…”

“…Inose et al (1992) compiled a yield table for A. mangium based on the data collected from the plantations in Saba, Malaysia. Similar yield tables, all of which assumed the normal stand density at each location, were published with the data from Bangladesh (Latif et al 1995), South Kalimantan (Forss et al 1996), and South Sumatra, Indonesia (Nirsatmanto et al 2003). It is empirically known that the A. mangium plantations rapidly increase its mortality since five years after planting, when they are left unthinned for pulp wood production.…”