Acacia Mangium Plantation Research Articles

Soil Water Conditions According to Landscape Position and Aboveground Vegetation in an Acacia mangium Plantation in Sabah, Malaysia

We studied the soil water dynamics of the humid tropics at a 1.6-ha Acacia mangium stand in Sabah State, northern Borneo, to quantify the effect of landscape position and vegetation on soil water conditions. We monitored the volumetric soil water content (VSW) at a depth of 30 cm at 12 locations in the research plot, every 30 min for 1 year using ADR theta probes. To analyze the drying process, twelve events were selected in the course of the research period when comparatively long intervals without rainfall occurred. The decline in soil water during the drying periods fit linear regressions well when we excluded the data from the first 24 h after the last rain event. The absolute value of the slope of the regression was termed the drying rate (DR). Topographic index, described as ln(α/tanβ) (a = upslope contributing area per unit contour; tanβ = local slope angle) was also determined. The range of the VSW in bottomland was smaller than for other landscape positions, but no significant relationship was observed between the topographic index and the VSW. The median DR was significantly correlated with tree density, and with the topographic index. During a drying period, evapotranspiration was the major factor controlling the soil water regime in this stand. The normalized DR according to tree density was significantly lower in the bottomlands, and described the wet gleyic characteristics of the bottomland well. The DR appeared to be a good indicator for detecting the effects of vegetation and topography on soil water conditions in the humid tropics.

Function and value of water conservation in different age classes of Acacia mangium plantations

For this paper, we studied the water-holding capacity of canopy, vegetation layer under canopy and litter layer, the water-holding capacity and permeability of soil as well as their changes with growth of stands in Acacia mangium plantations of three different age classes (four-, seven-and 11-year-old). Results show that total water-holding above ground in the order of 11-year stand age (52.86 t/hm2)>seven-year stand age (41.90 t/hm2)>seven-year stand age (25.78 t/hm2), the increment tendency increased with stand age. Similar sequence also obtained on the water-holding capacity and permeation capacity of soil (0–40 cm). The total water-storage capacity both above ground and soil in four-year-old, seven-year-old and 11-year-old of A. mangium plantations were 2,023.0, 2,158.4 and 2,260.4 t/hm2, respectively, and the all value of water conservation were 1,372.70, 1,474.42 and 1,549.91 yuan (RMB)/hm2, respectively. Therefore, A. mangium plantation had a good ability to modify soil structure and good water conservation function.

Impact of landscape and corridor design on primates in a large-scale industrial tropical plantation landscape

Tropical plantations are rapidly expanding as a source of industrial wood. In Indonesia, such large-scale industrial plantations are generally made of large mono-specific blocks interspersed with natural forest remnants. The extent and biodiversity value of these remnants vary as laws and regulations on their design and management are either unclear, without solid scientific basis or left to the interpretation of private companies responsible for the plantations. Our study area comprises of three Acacia mangium plantations, which have on average 18% of their total area set aside from production and conserved as natural forests. These remnant natural forests may, if appropriately designed and managed, be used to mitigate the negative impact of plantations on biodiversity by providing some degree of connectivity with and between remaining natural forest patches (such as the Tesso Nilo conservation area). We sampled natural vegetation in one and primate diversity in all three plantation sector and examined patterns of primate species richness and abundance with relation to spatial arrangement and dimensions of conservation area, which has been set aside from plantation production. We demonstrate unambiguously the critical importance of a well-connected network of natural forest corridors in the plantation landscape to maintain primates and discuss the potential biodiversity value of natural forest remnants in broad-scale industrial landscapes.

Soil changes induced by Acacia mangium plantation establishment: Comparison with secondary forest and Imperata cylindrica grassland soils in South Sumatra, Indonesia

Acacia plantation establishment might cause soil acidification in strongly weathered soils in the wet tropics because the base cations in the soil are translocated rapidly to plant biomass during Acacia growth. We examined whether soils under an Acacia plantation were acidified, as well as the factors causing soil acidification. We compared soils from 10 stands of 8-year-old Acacia mangium plantations with soils from 10 secondary forests and eight Imperata cylindrica grasslands, which were transformed into Acacia plantations. Soil samples were collected every 5–30 cm in depth, and pH and related soil properties were analyzed. Soil pH was significantly lower in Acacia plantations and secondary forests than in Imperata grasslands at every soil depth. The difference was about 1.0 pH unit at 0–5 cm and 0.5 pH unit at 25–30 cm. A significant positive correlation between pH and base saturation at 0–20 cm depth indicated that the low pH under forest vegetation was associated with exchangeable cation status. Using analysis of covariance (ANCOVA), with clay content as the covariate, exchangeable Ca (Ex-Ca) and Mg (Ex-Mg) stocks were significantly lower in forested areas than in Imperata grasslands at any clay content which was strongly related to exchangeable cation stock. The adjusted average Ex-Ca stock calculated by ANCOVA was 249 kg ha −1 in Acacia plantations, 200 kg ha −1 in secondary forests, and 756 kg ha −1 in Imperata grasslands at 0–30 cm. Based on a comparison of estimated nutrient stocks in biomass and soil among the vegetation types, the translocation of base cations from soil to plant biomass might cause a decrease in exchangeable cations and soil acidification in Acacia plantations.

Forest Fuel Inventory in 5 and 9-Year-Old Acacia Mangium Plantations

This study was conducted to determine the fuel components on forest floor of two different age stands and to estimate the fuel loading of the various fuel components. This study was carried out at Bukit Tarek Forest Reserve, Hulu Selangor, Selangor Darul Ehsan, at two stand age of Acacia mangium of 5 and 9-year-old. Fuel components of downed woody material and duff were sampled along transects lines. Shrubs, litter, herbaceous and small trees ( 1 of total fuel (downed woody material, litter and herbaceous), 1.73 cm of duff depth, 37,030 stem haG 1 of shrubs density and 2,175 tree haG 1 of small trees. The 9 year-old stand showed 17.42 Mg haG 1 of forest fuel, 3.03 cm of duff depth, 39,151 stem haG 1 shrubs density and 3,515 tree haG 1 of small trees. Downed woody material made up of 89 and 74% of the total fuel weight for 5 year and 9-year-old stands, respectively. Comparison between two different age stands, showed that 5 year old stand has higher quantity of downed woody materials than 9 year-old stand with 20.66 and 12.82 Mg haG 1 , respectively. Based on diameter class interval, the weight of downed woody material, diameter class of 0-7.6 cm were higher compared to diameter class of >7.6 cm. The fuel weight for 0-7.6 cm diameter class was 12.48 and 9.94 Mg haG 1 for 5 and 9-year-old stands, respectively. Statistical analysis showed that the loading of downed woody material on 5-year-old stand was significantly greater than the 9 year-old stand. However, litter loading was greater on the 9-year-old stand than the 5-year-old stand. The study concludes that in terms of fuel loading, 5-year-old stand has higher fire risk than 9-year-old stand. This is due to the silviculture activities in the 5-year old stand

A Parametric Model for the Interval Censored Survival Times of Acacia Mangium Plantation in a Spacing Trial

Survival times for the Acacia mangium plantation in the Segaliud Lokan Project, Sabah, East Malaysia were analysed based on 20 permanent sample plots (PSPs) established in 1988 as a spacing experiment. The PSPs were established following a complete randomized block design with five levels of spacing randomly assigned to units within four blocks at different sites. The survival times of trees in years are of interest. Since the inventories were only conducted annually, the actual survival time for each tree was not observed. Hence, the data set comprises censored survival times. Initial analysis of the survival of the Acacia mangium plantation suggested there is block by spacing interaction; a Weibull model gives a reasonable fit to the replicate survival times within each PSP; but a standard Weibull regression model is inappropriate because the shape parameter differs between PSPs. In this paper we investigate the form of the non-constant Weibull shape parameter. Parsimonious models for the Weibull survival times have been derived using maximum likelihood methods. The factor selection for the parameters is based on a backward elimination procedure. The models are compared using likelihood ratio statistics. The results suggest that both Weibull parameters depend on spacing and block.

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

Small volumes of timber are now being produced from Acacia mangium plantations in Indonesia. These trees require pruning and thinning to increase the strength and appearance of the wood. However, cut surfaces from pruning are potential infection courts for the entry of decay-causing fungi like heart rot. This study investigated the effects of pruning on stem form and the incidence of heart rot in an 18-month-old plantation of Acacia mangium in South Sumatra. The objectives were to assess whether pruning is associated with an increase in the incidence of heart rot and whether form pruning compared to lift pruning reduced the incidence of heart rot and improved stem form. Form pruning removed 25% of leaf area by removing large branches and those subtending a narrow angle with the stem up to 3 m height, and lift pruning removed 25% of crown length from below. Trees in these treatments were singled before pruning. The third treatment, a control, was not singled and was used to assess base levels of heart rot. No significant difference in diameter increment between the two pruning treatments was found. There was strong evidence that form pruning was associated with better form 18 months after treatment. Trees in this treatment had a reduced number of branches >30 mm diameter and improved stem straightness (reduced kink). Lift pruning reduced average branch size but did not improve stem straightness. No heart rot was detected in any treatment. The results showed that form pruning is likely to have positive benefits on stem straightness and is likely to be effective to any selected pruning height. However a subsequent lift pruning is still considered a requirement. While wounds created from pruning and singling are assumed to have a large impact on the incidence of heart rot, this may not be an issue unless there is a sufficient source of fungi present in the environment to invade the wounds.

Estimation of Forest Plantation Productivity Using a Physiologically Based Model Driven with Meteorological Data and Satellite-derived Estimates of Canopy Photosynthetic Capacity

Within the framework of Kyoto protocol, carbon sink concept is a major topic for the global climate change. There is an urgent need to collect some necessary data on the forest plantations. Therefore, there is a clear need to develop methods for estimating the biomass at diverse sites simply with non- destructive methods. Modeling is one of effective approaches and Process Based Models (PBMs) can provide a better understanding of stand growth and dynamics. A one simplified model of PBMs is 3PG model and modified one is 3PGS model; Physiological Principles Predicting Growth with Satellite data (1). The model enables to use parameters derived from satellite data such as Fraction of absorbed Photosynthetically Active Radiation (FPAR) as well as meteorological data. The objective of this study is to compare between 3PG model and 3PGS model by estimating above ground biomass (Wabv). Landsat Enhanced Thematic Mapper-Plus (ETM+) data were used for the model implementation. The estimated parameters were validated with the ground-measured values. Field measurements were conducted in Eucalyptus camaldulensis and Acacia mangium plantation. The 3PGS model outputs showed that there was very good relationship between measured (ground-based measurements) and simulated (modeled) values. Root mean square errors (RMSE) of 3PGS model results were less than the RSME of 3PG model results in Eucalyptus plot. The result applied for Acacia mangium showed it had higher RMSE between measured and simulated values than the result applied for Eucalyptus camaldulensis. The results indicate that the 3PGS model can provide reasonable estimates of Wabv.

Soil macro-fauna in an Acacia mangium plantation in comparison to that in a primary mixed dipterocarp forest in the lowlands of Sarawak, Malaysia

Summary Sustainable ecosystem management of Acacia mangium plantation, the area of which is rapidly increasing in the tropics, especially in Indonesia and Malaysia, becomes more and more important. In this context, abundance, biomass and vertical distribution of soil macro-invertebrates were investigated in a mature plantation of A. mangium in Sarawak, Malaysia. In the present paper, in order to reveal the changes in soil macro-fauna caused by conversion of natural forests to A. mangium plantations, the results were compared with those from a nearby primary forest. While total abundance of soil macro-invertebrates was similar, total biomass was much larger in the plantation than in the primary forest. The prominent factor for such a large total biomass in the plantation was the high abundance of earthworms, followed by isopods and harvestmen with much smaller contributions. The common feature of the communities of these three taxa in the plantation was the absolute dominance by single species. The dominant earthworm species was of the endogeic type that was absent from the primary forest and thought to be introduced with A. mangium seedlings from outside. The isopod flushed in the plantation was a pill bug that occurred in the primary forest, too, and might have been pre-adapted to the vegetation change. The dominant harvestman in the plantation was of the life form different from that of the other species found, and was thought to be supported by the explosive increase in biomass of earthworm and/or pill bug. On the other hand, communities of termites, ants, fly larvae, click beetle larvae and other beetle larvae were depressed by the vegetation change. Thus the major consequence of the conversion of natural forest to A. mangium plantation was simplification of community structure in many taxonomic groups. The major points of the simplification in turn were the explosive increase in biomass of the soil processing earthworm and the litter processing pill bug which may accelerate the mineralization processes. The need for a careful monitoring on sustainability of soil fertility was concluded.

Minimum distance boundary method: maximum size-density lines for unthinned Acacia mangium 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 10–21 cm 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 28–30 m2/ha at 12cm of dbh and then it increased up to 34–37 m2/ha at 20 cm of dbh.

Carbon Monitoring Costs and their Effect on Incentives to Sequester Carbon through Forestry

Technically, forestry projects have thepotential to contribute significantly tothe mitigation of global warming, but manysuch projects may not be economicallyattractive at current estimates of carbon(C) prices. Forest C is, in a sense, a newcommodity that must be measured toacceptable standards for the commodity toexist. This will require that credible Cmeasuring and monitoring procedures be inplace. The amount of sequestered C that canbe claimed by a project is normallyestimated based on sampling a number ofsmall plots, and the precision of thisestimate depends on the number of plotssampled and on the spatial variability ofthe site. Measuring C can be expensive andhence it is important to select anefficient C-monitoring strategy to makeprojects competitive in the C market. Thispaper presents a method to determinewhether a forestry project will benefitfrom C trading, and to find the optimalmanagement strategy in terms of forestcycle length and C-monitoring strategyA model of an Acacia mangiumplantation in southern Sumatra, Indonesiais used to show that forestry projects canbe economically attractive under a range ofconditions, provided that the project islarge enough to absorb fixed costs.Modeling results indicate that between 15and 38 Mg of Certified Emission Reductions(CERs) per hectare can be captured by thesimulated plantation under optimalmanagement, with optimality defined asmaximizing the present value of profitsobtained from timber and C. The optimalcycle length ranged from 12 to 16 years andthe optimal number of sample plots rangedfrom 0 to 30. Costs of C monitoring (inpresent-value terms) were estimated to bebetween 0.45 (Mg C)-1 to 2.11 (MgC)-1 depending on the spatialvariability of biomass, the variable costsof C monitoring and the discount rate.

Soil rehabilitation following tractor logging: early results on amendments and tilling in a second rotation Acacia mangium plantation in Sabah, Malaysia

Soil rehabilitation following tractor logging: early results on amendments and tilling in a second rotation Acacia mangium plantation in Sabah, Malaysia

Soil rehabilitation following tractor logging: early results on amendments and tilling in a second rotation Acacia mangium plantation in Sabah, Malaysia

Timber extraction with crawler tractors in humid tropical forests causes degradation of soil physical properties and decreases plant growth. We tested rehabilitation of tracks in a second rotation Acacia mangium plantation in Sabah, Malaysia, by tilling with additions of NPK-fertilizer, ash and organic material to a depth of 15–20 cm. Two years after planting total basal area of A. mangium seedlings was 62% higher outside tracks compared to unimproved tracks, while on NPK-fertilized tracks performance was 700% higher compared to unimproved tracks. Corresponding figures for average height were 40 and 80%. After 8 days with little rain track topsoil experienced water shortage with all studied soil improvements. For ‘non-tracked’ areas wilting-point (−1500 kPa) was not reached during 17 days of dry weather, and more meso-pores were present. Consequently, depending on rainfall after planting the effect of soil rehabilitation on tree performance may be less positive than shown here, because dry periods of 2 weeks length are common in the humid tropics. Bulk density on plots outside tracks in this second-generation plantation was 60% higher than have been reported in similar first-generation plantations. It is discussed that this might be a warning that repeated logging and fire may have a detrimental effect on soil physical properties.

Growth Analysis of Acacia Mangium Plantation in Southeast Asia

熱帯林荒廃の修復に早生樹として大面積造林が行われたアカシア・マンギウムについて、成長特性の分析を行った。アカシア類は産業造林の対象樹種として、東南アジア各国において、多数の植林実績があり、造林の成功に必要な条件の解明から、森林施業に関する成長データの解析まで、昨今研究が進められている。また、高能率なパルプ材生産が可能とされ、温暖化対策としてのCDM植林プロジェクトの点からも注目されている。ここでは半島マレーシアの造林データを中心に、他地域との成長比較を行い、施業モデルの作成について検討した。

Comparação da matéria orgânica e de outros atributos do solo entre plantações de Acacia mangium e Eucalyptus grandis

Espécies de eucalipto e acácia são amplamente utilizadas em plantios agroflorestais e reflorestamentos. Com o intuito de comparar a reconstituição das camadas orgânicas do solo, i.e., dos horizontes húmicos, estabelecendo-se uma relação com propriedades edáficas, sob plantações de Acacia mangium e Eucalyptus grandis, foram feitas coletas dos horizontes holorgânicos e hemiorgânicos do solo. Os referidos plantios encontravam-se na região de Tabuleiros Terciários no norte do estado do Espírito Santo e pertenciam à Reserva Natural da Vale do Rio Doce. As coletas foram feitas quando os plantios tinham sete anos de idade, em quatro estações. Acacia mangium apresentou maior estoque de folhiço (10 t ha-1, em média), tanto na camada L, de folhas inteiras, como na camada F, de folhas fragmentadas, do que Eucalyptus grandis (5 t ha-1, em média). O material foliar em acácia apresentou menor relação C/N que o de eucalipto, cerca da metade, decorrente dos maiores teores de nitrogênio. Quanto às análises químicas de carbono e nutrientes, no solo sob Acacia mangium, foram observadas, de modo geral, maiores quantidades destes elementos que no solo sob Eucalyptus grandis (e.g., carbono: 1,74 dag kg-1 vs 1,23 dag kg-1 e cálcio: 3,34 cmol c kg-1 vs 2,75 cmol c kg-1). O conjunto destes resultados evidencia que os aportes orgânicos sob Acacia mangium em relação a Eucalyptus grandis foram responsáveis pela maior incorporação de matéria orgânica e nutrientes ao solo. Estes dados, no entanto, comparados aos obtidos em estudos na floresta primária, mostraram que o carbono e os nutrientes do solo, em ambas as plantações, são menores que na floresta, evidenciando que, após sete anos de plantio, os teores de fertilidade e matéria orgânica do subhorizonte A11 não estavam restabelecidos.

Characteristics of Ultisols differing in wildfire history in South Sumatra, Indonesia

In spite of the significant increase in the frequency and extent of fire occurrence in Indonesia recently, little information is available about the immediate, short-term, and long-term effects of fire on soils. To investigate the effects of wildfires on the dynamics of T-C, T-N, available P, pH, exchangeable bases, and cation exchange capacity (CEC) of Ultisols from South Sumatra Indonesia, surface soils of an unburnt 9-year old Acacia mangium plantation and of A. mangium plantations burnt in 1995, 1997, 1998, and 2000 were sampled in triplicate consecutively from December 1998 until December 2000. The values of T-C, T-N, available P, pH, and exchangeable bases significantly increased immediately after the fire while the levels of Al saturation and CEC significantly decreased. Soil nutrients were still accumulated 1 year after the fire but by the end of the second year, they were depleted and returned to the pre-fire levels. Although fallowing aggraded the burnt sites, the nutrient levels in the burnt sites were still lower than those in the unburnt sites. In addition, the residual effects of fire on the soil nutrient levels were still evident 5 years after the fire.

Characteristics of Ultisols under Different Wildfire History in South Sumatra, Indonesia: I. Physico-chemical Properties.

Fire has become a great threat to Indonesian rainforest. However, informative data quantifying the effects of wildfire on the soils are still limited. We have been studying the leftover effect of forest fire on characteristics of Indonesian Ultisols. Current experiment evaluated physico-chemical characteristics of soils under different ecosystems with different wildfire history. Seven sites, which could be grouped into unburnt sites (conservation forest (CF), Pine forest (iF), Acacia mangium plantation (AM), and home garden (HG)) and burnt sites (Acacia mangilan plantations bumt in i995,L997, and 1998) referred as AM-b95, AM-b97, and AM-b98, respectively, were sampled. Organic layer was found in CR PR and AM but not in any other sites. Morphologically, soils of unbunt sites had darker A horizon than those of burnt sites. In spite of lack of significant differences, bulk density decreased with increasing period after fire, indicating the recovery process. Although the upper layer of the bunt soils was physically harder than that of the unbumt soils, soil hardness did not appear to be a limiting factor for plant growth. Soil in the unbumt sites was chemically more acid but contained more organic C and N than that in the burnt sites. Surface soil of PF, AM-b98, and HG had much higher exchangeable Ca than any other sites. However the CEC was low across the study sites, irrespective of the high clay content. Available P was also low, and correlated with high Al solubility. Crysialline Al, Si, and Fe contents of all soils were higher than amorphous Al, Si, and Fe oxides. ZpC values were low across the study sites. However, higher negative charge generated by organic matter had resulted in lower ZPC values at the surface layer as compared with the subsurface layer. Although soils in the unbumt sites showed a better physico-chemical potential than the bunt site, in general Ultisols in the study sites had undergone strong weathering and showed low natural fertility potential.

Tree sap flow and stand transpiration of two Acacia mangium plantations in Sabah, Borneo

Water use of Acacia mangium trees grown in plantations was measured by a heat balance method in two stands that largely differed in tree density. Tree sap flow was closely coupled to climatic drivers and responded with minimal time delay. Using no time shift, sap flow rate could be tightly fitted to a simple equation that combined a parabolic response to radiation and an inverse linear response to air humidity. On the contrary, the analysis of canopy conductance showed no meaningful response to either individual or combined microclimatic variables. No indication of water deficit was observed, though the measurement period was during the dry period of the year. The measurements indicate a minimal diurnal use of water stored in plant tissues. The difference in tree water use from the two studied stands was effectively scaled by tree sapwood area. Canopy transpiration of the densest stand reached in average 3.9 mm d −1 compared with 2.7 mm d −1 for the stand representing the average conditions in the catchment.

The Flammability of Shrubs and Trees in an Acacia mangium Plantation Based on Silica-free Ash Content

Preliminary research to understand the flammability of 14 species of shrubs and 8 species of trees based on silica-free ash content was done in order to recognize which shrubs or trees are more flammable. The results show that the silica-free ash content of shrubs and trees leaves was greater than the stems ranging between 1.7% and 11.4% for leaf and 0.4% and 7.8% for the stems. The shrubsDicranopteris linearis, Imperata cylindrica, Eupatorium pubescens, Lantana camara, Eugenia sp.,Cliforia laurifolia, Pterospermum sp.,Hibiscus similis, Clidemia hirta andTrema orientalis must be considered when fire invades the plantation as well as the treeParaserianthes falcataria, Eucalyptus urophylla, Calliandra callothyrsus, andPeronema canescens.

EARLY PERFORMANCE OF TEN TIMBER SPECIES PLANTED UNDERACACIA MANGIUMPLANTATION ON ANIMPERATA CYLINDRICAGRASSLAND SITE IN SOUTH KALIMANTAN, INDONESIA

ABSTRACT Early performance of nine indigenous and one exotic shade-tolerant timber species planted under an 8-year-old Acacia mangium plantation on an Imperata cylindrica dominated grassland site was studied for three years in South Kalimantan, Indonesia. The aim was to investigate the differences in early survival and growth between these species. Twenty seedlings of each species were planted in a completely randomized design between the rows of A. mangium. Three years after planting, Anisoptera marginata and Eusideroxylon zwageri showed no mortality, Swietenia macrophylla had a survival of 85%, Dipterocarpus grandiflorus 80% and Shorea balangeran 70%. Other dipterocarps had a mortality of 35–80% during the third year when serious drought occurred. S. macrophylla had a slow initial height growth but thereafter clearly outperformed other species, reaching a cumulative height increment of 267 cm during 36 mo. Height increments of A. marginata, S. balangeran and E. zwageri were 121, 97 and 78 cm, respective...