Variation of heartrot,sapwood infection and polyphenol extractives with provenance of Acacia mangium

Infection of heartwood by decay fungi (heartrot) is a concern for growers of Acacia mangium for solid‐wood products as the incidence can be high in some regions of Indonesia. Variation of heartrot incidence for different provenances of A. mangium was determined using two field trials in Sumatra, Indonesia. In a Riau Province trial of 21 provenances, the effect of provenance was statistically significant for natural heartrot incidence, which ranged from 1.6% to 27.2%. In a smaller trial using artificial inoculation in South Sumatra, heartwood infection incidence ranged from 39.4% to 70.8% across six provenances and both wound type and provenance were statistically significant factors. There was also significant variation in sapwood infection length related to provenance. Wood extractives (yield, total phenols, protein‐precipitable tannin and 2,3‐trans‐3,4′,7,8‐tetrahydroxyflavanone) were quantified from a subsample of trees for each trial. However, no significant differences in extractive concentration were detectable according to provenance and evidence for a relationship between heartwood extractives and heartrot incidence was generally poor. While further studies need to be completed to establish the basis for heartrot incidence, results from these trials allow for recommendations on provenance selection to reduce heartrot incidence and provide information for further genetic selection programmes.     

Marennine,Promising Blue Pigments from a Widespread Haslea Diatom Species Complex

In diatoms, the main photosynthetic pigments are chlorophylls a and c, fucoxanthin, diadinoxanthin and diatoxanthin. The marine pennate diatom Haslea ostrearia has long been known for producing, in addition to these generic pigments, a water-soluble blue pigment, marennine. This pigment, responsible for the greening of oysters in western France, presents different biological activities: allelopathic, antioxidant, antibacterial, antiviral, and growth-inhibiting. A method to extract and purify marennine has been developed, but its chemical structure could hitherto not be resolved. For decades, H. ostrearia was the only organism known to produce marennine, and can be found worldwide. Our knowledge about H. ostrearia-like diatom biodiversity has recently been extended with the discovery of several new species of blue diatoms, the recently described H. karadagensis, H. silbo sp. inedit. and H. provincialis sp. inedit. These blue diatoms produce different marennine-like pigments, which belong to the same chemical family and present similar biological activities. Aside from being a potential source of natural blue pigments, H. ostrearia-like diatoms thus present a commercial potential for aquaculture, cosmetics, food and health industries.     

Productivity of successive rotations of Acacia mangium plantations in Sumatra,Indonesia: impacts of harvest and inter-rotation site management

The impacts of wood harvest, biomass removal and inter-rotation site management practices on productivity of Acacia mangium in South Sumatra were studied over 12 years across successive rotations. The productivity measured as MAI increased from 29.4 m³ ha^?1 year^?1 in the first to 48.0 m³ ha^?1 year^?1 in the second rotation. Whole tree harvesting (total stem, branches and leaves) caused a 21 % reduction in volume compared to harvesting merchantable wood alone in the next rotation. The rates of nutrients accumulation in trees were highest during the first year of growth, and declined from age 2 years. Significant amounts of nutrients were recycled through litter fall from 1 year after planting. Results highlight the importance of management which promotes nutrient supply on stand growth. Removal of slash and litter lowered soil pH, by about 0.1 unit. A small reduction was also found in soil organic carbon and nitrogen in the top soil during the first 3–4 years but values returned to pre-harvest levels by the end of the rotation. Extractable soil phosphorus and exchangeable cations decreased by the end of second rotation but these measures underestimate the nutrient pools available for A. mangium. These findings along with results from other studies have helped to implement operations which promote conservation of site resources for sustainable production in the region.     

Seroprevalence of antibody to NcSAG1 antigen of Neospora caninum in cattle from Western Java,Indonesia

Neospora caninum can cause fetal abortion and neonatal mortality in cattle, and is a cause of economic concern worldwide. This study aimed to determine the prevalence of Neospora caninum-specific antibodies in cattle from Western Java, Indonesia. Serum samples from 991 cattle from 21 locations were tested for antibodies to N. caninum by using an enzyme-linked immunosorbent assay (ELISA) on the basis of recombinant NcSAG1. The overall seroprevalence was 16.6%, ranging from 0 to 87.5% in the sampled locations. The results of this study indicate latent infection rates of sampled animals were different in each location. Further studies are necessary to elucidate the relationship between N. caninum infection and abortion in cattle, and to identify risk factors for infection in high-prevalence environments.     

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

 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. Received: July 24, 2002 / Accepted: December 3, 2002 Acknowledgments The authors thank Mr. Hardjono, the director of plantation establishment at PT Musi Hutan Persada for his permission to use data of permanent plots for the growth modeling of A. mangium. The authors are grateful to the staff at PT Musi Hutan Persada, Research and Development Center for Biotechnology and Forest Tree Improvement, Japan International Cooperation Agency for their implementations of the study. Our thanks are also due to Dr. Yoshida, associate professor at Kyushu University, for his advice on developing the growth modeling work. Correspondence to:S. Kurinobu     

Minimum distance boundary method: maximum size-density lines for unthinned <Emphasis Type="Italic">Acacia mangium</Emphasis> plantations in South Sumatra,Indonesia

A minimum-distance boundary method that will minimize the sum of distances between measured points and a fitted self-thinning lines on log–log coordinates of stand density and quadratic mean diameter was proposed in order to estimate the maximum size density line: an upper boundary of self-thinning line. The lines for A. mangium were inferred with this method using data in two areas of unthinned plantations in South Sumatra, Indonesia. Slopes of the lines were deduced as –1.63 and –1.67 within the range of 10–21cm of quadratic mean dbh. The intensity of self-thinning was examined as a rate of reduction of density in relation to dbh increment. The rates were found to be higher than the slopes in the range close to the maximum line; hence the lines inferred in this study were likely existent. Maximum basal area deduced from the size-density line was 28–30m²/ha at 12cm of dbh and then it increased up to 34–37m²/ha at 20cm of dbh.     

Effects of <Emphasis Type="Italic">Eucalypt</Emphasis> and <Emphasis Type="Italic">Acacia</Emphasis> plantations on soil water in Sumatra

Indonesia’s pulp and paper industry needs a large area of sustainably grown plantations to support its continued development. Acacia mangium has been the key species underpinning the pulp and paper industries in Sumatra, however increased disease pressure on A. mangium is expected to require large-scale conversion of Acacia plantations to Eucalyptus in the near future. The effect of such a large scale change in plantation species on soil moisture, for both tree production, and catchment hydrology is unknown. In this study we sought to characterize the impacts of plantation species (Acacia or Eucalyptus) and nitrogen management, on soil moisture, soil water depletion and depth to groundwater under stands of Acacia mangium and Eucalyptus pellita over the first 2–3 years after establishment. The study was conducted in experiments at four sites in Sumatra, Indonesia. Soil moisture and soil water depletion were not influenced by plantation species or fertilizer treatment. Soil moisture content and soil water depletion were strongly influenced by shallow groundwater at two of the four sites, however depth to groundwater did not influence stem growth. Results from the field trials cautiously suggest that large scale conversion of Acacia mangium to Eucalypt species in these regions is unlikely to result in increased moisture stress, nor is conversion of plantation species likely to lead to substantial differences in catchment hydrology. This study demonstrated the importance of conducting multi-site studies when investigating biophysical relationships in forest/plantation systems.     

The complexity and consequences of the policy implementation dealing with sustainable ideas

This article portrays a case study in Yogyakarta, Indonesia which looks into the dynamic relationship between communities and the effectiveness of the implementation of community-based forest management (CBFM) policies and its programme, and particularly on how local institutions deal with the shifting dynamics of these policies. As there is currently an absence of research in this area, this research therefore focuses on how the local community implements policy, builds relationships with other stakeholders, and strengthens local community institutions.

CBFM has been implemented in Yogyakarta since 1995 and during that time, the central government has been changing the policy for five times. At this point, this article argues that CBFM should rely on local institutions and deal with the shifting dynamics of policies. The terms of institutions can be considered to include formal institutions, such as Constitution, government laws, charters, decrees and statutes, and informal institutions, such as code of conducts, customs, local knowledge and social expectations. Furthermore, in selected communities, it is clear that the local communities can apply their informal institutions as an important component and value of traditional systems and significantly involved in forest management sustainability and establish the formal institutions simultaneously.     

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

A simple step-wise procedure for predicting the course of stand development on log–log coordinates of stand density and quadratic mean diameter was presented based on a distance of measurement from the maximum size–density line of Acacia mangium. This procedure first predicts annual increment of diameter with a multiple linear regression having the distance, site index, and current diameter as independent variables, and then the associated mortality is calculated with the rate of reduction in stand density to the diameter growth derived from a fitted trend with the distance. The cumulative predictions, starting at 3 years after planting until 9 years of age, agreed well with the observations of group-age means of measurements calculated for the three levels of initial density. Contrasting trend of basal area growth between the three levels of initial density and those for their site index: the differences were decreasing in the former while they remained constant in the latter, was clearly illustrated with the procedure indicating a good potential for use in yield prediction. The simulations for stand growth under different spacing and thinning options were demonstrated in a stand density control diagram suggesting reasonable flexibility for practical application.