New Forest 28: 277–285, 2004.
# 2004 Kluwer Academic Publishers. Printed in the Netherlands.
Sustainable site productivity and nutrient
management in a short rotation plantation of
Gmelina arborea in East Kalimantan, Indonesia
CAHYONO AGUS1,2,*, OKA KARYANTO1, SATOSHI KITA2,
KIKUO HAIBARA2, HIROTO TODA2, SURYO HARDIWINOTO1,
HARYONO SUPRIYO1, MOHAMAD NA’IEM1, WAHYU WARDANA3,
MAURIT S. SIPAYUNG3, KHOMSATUN4 and SUHARTONO WIJOYO3
1Faculty of Forestry, Gadjah Mada University, Yogyakarta, Indonesia; 2Faculty of Agriculture, Tokyo
University of Agriculture and Technology, Tokyo, Japan; 3PT Sumalindo Lestari Jaya, Samarinda,
Indonesia; 4PT ITCI-KU, Balikpapan, Indonesia; *Author for correspondence (e-mail: itto-gmu@
yogya.wasantara.net.id.
Received 5 April 2003; accepted in revised form 10 December 2003
Key words: Land use change, Legume cover crop, Short-rotation plantation, Site quality, Sustainable
forest nutrient management, Tropical forest
Abstract. Sustainable Forest Management (SFM) requires information on plant growth and nutrient
dynamics in forest ecosystems. To obtain fundamental information for SFM in short-rotation plantations in
tropical regions, a serial study was conducted on: (i) land use changes and effects on soil chemical
properties in tropical forestland, (ii) site index and nutrient dynamics in Gmelina arborea Roxb. (yemane),
(iii) stand age and nutrient cycles in the first rotation of a yemane plantation on a moderately productive
site, and (iv) biomass and N2-fixation of legume cover crops (LCC) for soil amelioration. Land use change
from natural stands to plantations was linked to a decrease in electric conductivity (EC), cation exchange
capacity (CEC), total carbon (T-C), carbon to nitrogen ratio (C=N ratio) and exchangeable ca. Three sites
classified by productivity (poor, moderate and good) were examined using annual inventory data from 3 to
4% sampling intensity of yemane plantations in the Sebulu site, PT Sumalindo Lestari Jaya. The growth of
yemane was very rapid during the first 6 years and was strongly influenced by site quality. The differences
in average stand height between the site classes at 6 years were 3m, representing stand volume differences
of approximately 40m3 ha1. Whole-tree harvesting removed 50% of the aboveground biomass and
nutrients. The good site had greater amounts of total phosphorus (T-P), total calcium (T-Ca), total magnesium
(T-Mg), available P, and exchangeable Ca and Mg in the soil than moderate and poor sites. There
were no significant differences in nutrient amounts in the soil at different stand ages (4, 6 and 8 years of
age). The effects of site class on the topsoil characteristics were greater than those for land use change and
stand age. Yemane plantations in tropical regions are supported more by nutrient cycling rate than by the
amount of nutrient availability in soil. Nitrogen and phosphorus were the limiting nutrients for yemane
growth and regeneration in East Kalimantan. Legumes can promote sustainable site productivities in shortrotation
plantations in tropical forests by supplying N to the soil through N2-fixation and organic matter.
Annual N2-fixation from the atmosphere by LCC was 10–60 kgNha1 yr1. Application of fertilizer needs
to be considered for development of yemane on very poor soils.
Palabras clave: Cambios del use de la tierra, Cultivos de leguminosas, Plantacio´n de corta rotacio´n,