Study on the characteristics of organic biofertilizer made from composted scrap materials from Acacia plantations to produce substrates for cultivating seedlings in nursery

Abstract

The use of organic biofertilizer made from tree harvesting residuals (leaves,
branches and bark) inoculated with cenllulose decomposition
microorganisms as the nursury potting medium for seedlings production has
been popular in the world. In this study, one ton of chips of residuals from
harvested acacia plantations including leaves, branches and bark were added
with 3kg potassium, 10kg super phosphat, 5kg urea, inoculated with 5kg of
subtrates of cenllulose decomposition microorganisms to produce organic
fertilizer to use as potting medium for seedling production in the nursery.
After 90 - 105 days of inoculation, the compost has humidity of 25 - 35%,
pH
H2O
of 6.2 - 6.8, total organic matter of 32 - 32.5%, total nitrogen content
of 1.9 - 2.5%, total phosphorus content of 0.25%, total potassium content of
0.21 - 0.25%, and the color of black brown. The highest nutrient contents
was found in the biofertilizer composted in the period from 90 to 105 days.
The mixture of 30% biofertilizer, 69% topsoil and 1% phosphate fertilizer
(CT3) showed the best growth rate of 90 old - day Acacia mangium
seedlings, which has 26.4% in stem diameter and 148% in height higher
than those of the control. This mixture was 40% organic biofertilizer, 59%
topsoil and 1% phosphate fertilizer (CT4) for Dalbergia tonkinensis
seedlings, which has 14.8% in stem diameter and 14.8% in height higher
than those of the control.