In logged-over forests, altered light conditions with logging induce pioneer species invasion and reduce commercial value. In Indonesia, reduced impact logging (RIL) methods have been applied to mitigate the logging effects, and line planting of useful species has been conducted in some production forests. However, quantitative assessments of canopy openings during RIL and line planting treatment are insufficient. Line plating involves 3-m strip cutting lines. The effects of these methods on canopy openness are poorly understood. This study assessed the effects of different logging systems on light conditions using hemispherical photographs taken in plots set in primary forests, forest logged over using RIL, and forest treated with strip cutting after RIL. Photographs were also taken along strip cutting lines. The comparison of canopy openness among the three types of sites revealed that logging activities had significant effects on light condition. High levels of canopy openness were found along skid trails and logging gaps following the trails. Therefore reducing the impact on light conditions should be considered when planning skid trails. Between the logged-over forest plots with and without the strip cutting lines, there was no significant difference in the mean canopy openness. However, strip cutting treatment affected to sun fleck duration in the forest floor. It might influence to following dynamics. And there were large differences in canopy openness along each line which would cause variations in the growth of planted trees.

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This paper reported the characteristics of the contrasting soils occurring on the west (right) and east (left) banks of the middle reaches of Kahayan River in Central Kalimantan. On the west bank, a flat riparian forest was used for agriculture by local Dayak villagers. Totally 20 sites were studied, including rice-cropping fields, fallow forests and rubber gardens. The soils were classified as Oxyaquic Dystrudepts or Typic Dystrudepts. The soils were primarily characterized by high clay contents. While differences in soil properties were not appreciably observed in terms of land uses, pH, CEC, ECEC, and exchangeable Al were highly correlated with clay contents, indicating that clay content was a determinant factor for soil acidity and cation retention capacity of soils. The T-C contents were relatively high. Bulk density was significantly correlated with T-C content at the 0-10cm and with T-C and clay contents at the 30-40cm layer. Lepidocrocite was detected as a clay mineral component in spite of higher contents of exchangeable Al. Meanwhile, on the east bank, heath forest extended on the sandy alluvial terrace. The soils were very sandy and quite low in CEC and nutrients and were classified into Spodic Quartzipsamments. The soils at fire-degraded sites were less acidic than at logged-over sites. However, statistical difference was found only in exchangeable Ca, indicating that most of the nutrients derived from ash were lost away due to sandy soil texture.

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We investigated the effects of phosphorus (P) application on root respiration (RR) and heterotrophic microbial respiration (MR) in an Acacia mangium plantation using a trenching method. Mean RR was 0.46g Cm^-2 day^-1 in a non-P-applied plot, which accounted for 16% of total soil respiration, exhibiting a lower RR value and proportion of total soil respiration compared with previous studies. Mean MR was 2.41g Cm^-2 day^-1, accounting for 84% of the whole soil respiration. P application significantly (P <0.01) increased the mean RR from 0.46 to 0.88g Cm^-2 day^-1. Applied P was readily absorbed by acacia trees, which was inferred from the lower available P and total P in non-trenched plots compared to the trenched plots, and it is likely that the absorbed P stimulated root activities and RR. P application also significantly (P <0.001) increased the mean MR from 2.41 to 2.89g Cm^-2 day^-1, probably because P application relieved the P shortage and stimulated microbial organic matter decomposition. Our study suggests that when assessing the effects of P fertilization on C cycling in forest plantation, we should take account of the effects on organic matter decomposition and soil respiration, not only the effects on C sequestration by trees.

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Since the 1990s, Indonesian natural resources have become increasingly scarce. The wood processing industry was not only reductive and in need of reorganization but also needed to change its procurement methods for raw materials. In response to this situation, the Indonesian government has encouraged planting trees on private land and these planted areas have increased steadily in recent years in Java. In order to ascertain the extent of natural forest resources depletion, we analyzed data from phone interviews to the wood processing industry in Java about changes in raw material utilization. There were 159 mills that had more than 100 employees and we received responses from 95 (59.7%) of these mills. The interview results indicate that the number of mills utilizing state forest wood decreased whilst the number of mills utilizing private forest wood increased. Use of private plantations predominated and more than a quarter of the mills utilized sengon (Paraserianthes falcataria). From the interview to Company B and management data, it is clear that the company changed their source of wood from state forest to private forest because of a decrease in the state forest wood supply. In recent years the company has started contract plantations with local people. Increased demand for private forest timber and rising wood prices means that timber sourcing and supply through contract plantations is a necessary new direction in Javanese forestry.

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