Life Cycle Assessment of Wood Pellet Product at Korintiga Hutani company, Central Kalimantan, Indonesia

Climate change has forced human being to adapt in fulfilling their energy needs sustainably. In Indonesia, forestry activities has been considered as an emission rather than carbon sink. This study aims to analyze the inputs, outputs, and potential environmental impacts of wood pellet production in a forest company using life cycle assessment (LCA). The wood pellet is made from Eucalyptus pellita plantation. Analysis was made for 1 planting cycle or 6 years, and allometric equations were used to estimate the ability of industrial timber plantation forest to absorb CO2. Production of wood pellet starting from plantation requires inputs as follows: diesel fuel, electricity, NPK and other fertilizers, pesticides, and electrical energy. Those inputs produced emissions, of which the largest was N2O of 551.2927 kg, followed by NH3 of 7.5275 kg generated from NPK fertilizer. Another was PO43- amounted at 0.1792–0.2229 kg from liquid fertilizers and pesticides. Potential acidification came from 13.3675 kg SO2 eq, and eutrophication of 0.4021 kg PO43- eq. The greenhouse gas (GHG) emission was 678.0270 kg CO2 eq from the plantation activities, especially from diesel-based energy consumption, while wood pellet mills only released 0.1053 kg CO2 eq of GHG emissions. Thus, total emissions from 6 years' time of wood pellet production are much lower compared to the average CO2 absorbed by the plantation forest, of which annually is 36.34–67.69 ton ha-1year-1.

Growth Response to Weed Control and Fertilisation in Mid-Rotation Plantations of Eucalyptus pellita in South Sumatra, Indonesia

We report on a study of mid-rotation weed control and nutrient management in Eucalyptus pellita plantations in South Sumatra. The study was established at two contrasting sites (representing high and low productivity for the region) that had previously carried three rotations of Acacia mangium. A combination of weed control, nitrogen (N), and phosphorus (P) fertiliser were applied at 1 and 2 years after establishment. We found that the addition of up to 250 kg N ha−1 applied either at 1 year or 2 years after planting did not improve growth. The application of P (30 kg P ha−1) at age 1 year (in addition to 12 kg P ha−1 applied at planting) did not enhance tree growth either. Keeping the plantation free from weed competition throughout rotation (full weed control) enhanced wood volume up to age 4 years at the high-productivity site, while it improved wood volume up to the end of rotation at age 6 years at the low-productivity site. An additional experiment assessing the effect of weed control in the early phase of plantation establishment revealed that weed competition reduced young tree growth of E. pellita substantially. The results of the studies support the current practice of plantation management of E. pellita in the region that applied only P fertiliser at planting time and that kept trees free from weed competition before canopy closure. Full weed control throughout rotation is worth practicing at lower-productivity sites to achieve maximum productivity.

Sprouting and rooting ability of the plus trees of Eucalyptus pellita, E. brassiana and its hybrid in Wanagama, Indonesia

The demand for eucalypts has greatly increased since they are raw materials for timbers, plywoods, pulp and papers, and essential oil production. This study aimed to select the plus trees and determine the sprouting and rooting ability of E. pellita, E. brassiana, and their hybrids in Wanagama. Plus trees selection and girdling were conducted in December 2019. Cuttings were picked from the 3rd-4th nodes of sprouting at 8-10 cm in length. A completely randomized design was applied in a factorial experiment with three levels of Indole Butyric Acid (IBA) (100, 1000, and 4000 ppm) and two types of media (media 1: sand, rice husk charcoal and cocopeat (2:2:1), media 2: sand, topsoil and dung-fertilizer (2:2:1)), with ten replications. Results selected a total of 53 plus trees candidates (29 of E. pellita, 12 of E. brassiana, and 12 of hybrid). E. pellita is the best in sprouting ability (100% survival; 41-60 shoot/trees, 127-161cm shoot length, 0.53-0.57cm shoot diameter, and 194-252 leaves/shoot). Cuttings of E. pellita treated with 100 ppm IBA gained the highest survival and leaves production (96%-100%; 14-16 leaves), followed by E. brassiana (52%-66.67%; 7 leaves) and the hybrid (4% to 8.33%; 3-4 leaves). These results may contribute to arranging better strategies for mass production of selected eucalypts.

Early Monitoring of Health Status of Plantation-Grown Eucalyptus pellita at Large Spatial Scale via Visible Spectrum Imaging of Canopy Foliage Using Unmanned Aerial Vehicles

Eucalyptus is a diverse genus from which several species are often deployed for commercial industrial tree plantation due to their desirable wood properties for utilization in both solid wood and fiber products, as well as their growth and productivity in many environments. In this study, a method for monitoring the health status of a 22.78 ha Eucalyptus pellita plantation stand was developed using the red-green-blue channels captured using an unmanned aerial vehicle. The ortho-image was generated, and visual atmospheric resistance index (VARI) indices were developed. Herein, four classification levels of pest and disease were generated using the VARI-green algorithm. The range of normalized VARI-green indices was between −2.0 and 2.0. The results identified seven dead trees (VARI-green index −2 to 0), five trees that were severely infected (VARI-green index 0 to 0.05), 967 trees that were mildly infected (VARI-green index 0.06 to 0.16), and 10,090 trees that were considered healthy (VARI-green index 0.17 to 2.00). The VARI-green indices were verified by manual ground-truthing and by comparison with normalized difference vegetation index which showed a mean correlation of 0.73. This study has shown practical application of aerial survey of a large-scale operational area of industrial tree plantation via low-cost UAV and RGB camera, to analyze VARI-green images in the detection of pest and disease.

Fuelwood Characteristics of Five Species Grown in Merauke Forest

Papua has a large area of production forests, such as in Merauke. These forests provide great benefits for the pulp and wooden industries, which generate a large amount of biomass waste. Therefore, this study aimed to investigate the proximate analysis, specific gravity, calorific value, and Fuelwood Value Index (FVI) of wood and bark of five species, namely Acacia mangium Willd, Acacia crassicarpa A. Cunn, Eucalyptus pellita F. Muell, Melaleuca viridiflora Sol. Ex Gaertn, and Lophostemon suaveolens Sol. Ex Gaertn. The calorific value ranged from 4,066 to 5,435 cal/g, while the FVI values ranged from 4.04 to 76.41. The highest calorific value was observed in the bark of Melaleuca viridiflora, while the highest fuelwood value index was observed in Eucalyptus pellita wood. Furthermore, the calorific value of wood was higher compared to the bark in all species. There was no significant correlation between specific gravity, calorific or FVI value. It is noticed that a strong correlation (r = -0.92*) was observed between the calorific value and volatile matter in the bark. Based on the proximate analysis results, only the moisture content level was significantly correlated with the calorific value of wood or bark.

Productivity of Eucalyptus pellita in Sumatra: Acacia mangium Legacy, Response to Phosphorus, and Site Variables for Guiding Management

We report on experimental studies conducted in South Sumatra with interrelated objectives to (i) examine the trends in production covering 30 years, including three rotations of Acacia mangium followed by Eucalyptus pellita which replaced A. mangium for managing the widespread threat of diseases; (ii) understand the effects of inter-rotation slash and litter management applied to acacia (legacy effects) on E. pellita growth; (iii) assess the long term changes in the top soil layer arising from above; (iv) evaluate, through a network of experiments, across the landscape, the nature and extent of growth responses to additional phosphorus. This data was also used to explore some of the critical site and stand variables which determine the variations in productivity and responses to management. The current growth rates of E. pellita are lower than those achieved in A. mangium. The management-legacy effects by conserving site resources provides a sustainable base for the growth of E. pellita, but for further increase in productivity, additional management actions are necessary. Changes in soil pH, carbon, N and extractable P were relatively small after four rotations. Supply of P at planting gave wood volume gains at harvest, ranging from 16 to 66% across sites. The plinthite layer in the soil profile was related to productivity, with higher growth rates of E. pellita occurring when the plinthite was at deeper layers. There is much scope for increasing productivity per unit area in this landscape, and available knowledge can be synthesized into a package of best practices for application. Management should aim to improve the quality of inter-rotation management to ensure more than 90% survival, and fast growth rates during the first 2 years. We provide a framework for further research and for refining management to produce the much needed additional domestic wood supply for the local industry.

Early Root Development of Eucalyptus pellita F. Muell. Seedlings from Seed and Stem Cutting Propagation Methods at Nursery Stage

Macropropagation using cutting for larger multiplying seedlings is cheaper and efficient instead of clonal seeds for uniform plant material seedling production. However, information on root growth of Eucalyptus pellita at early development from seed and stem cutting of E. pellita seedlings is still lacking. With such information, it is useful for forest plantation company management in enhancing the understanding of strategies to optimize yield production with the appropriate agronomic or silvicultural approach in the field of planting. Therefore, the objectives of this study were to compare the root development of two different types of propagation seedlings of E. pellita and to study the effect of various nitrogen concentration levels on two different types of propagation of E. pellita seedlings. The study was conducted using E. pellita seedlings from two different types of propagation, namely, seed and stem cuttings, along with three different nitrogen concentrations (0, 50, and 200 kg N ha−1). Shoot biomass, root intensity (RI), total root intensity (TRI), root biomass, root length density (RLD), and specific root length (SRL) were recorded. Dried shoot biomass, RLD, and SRL of E. pellita seedlings using stem cutting were significantly higher ( P < 0.05 ) compared to seed, whereas there were no significant differences ( P > 0.05 ) for root biomass, TRI, and RI between the propagation types of E. pellita seedlings. In conclusion, E. pellita seedlings from stem cutting were greater in terms of root distribution compared to propagation by seeds at the nursery stage, and 50 kg N ha−1 was the optimal nitrogen concentration level from the considered levels to be applied to the E. pellita seedlings.