Jurnal Manajemen Hutan Tropika
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The Interpolation Method for Estimating the Above-Ground Biomass Using Terrestrial-Based Inventory
Get PDFThis paper examined several methods for interpolating biomass on logged-over dry land forest using terrestrial-based forest inventory in Labanan, East Kalimantan and Lamandau, Kota Wringing Barat, Central Kalimantan. The plot-distances examined was 1,000−1,050 m for Labanan and 1,000−899m for Lawanda. The main objective of this study was to obtain the best interpolation method having the most accurate prediction on spatial distribution of forest biomass for dry land forest. Two main interpolation methods were examined: (1) deterministic approach using the IDW method and (2) geo-statistics approach using Kriging with spherical, circular, linear, exponential, and Gaussian models. The study results at both sites consistently showed that the IDW method was better than the Kriging method for estimating the spatial distribution of biomass. The validation results using chi-square test showed that the IDW interpolation provided accurate biomass estimation. Using the percentage of mean deviation value (MD(%)), it was also recognized that the IDWs with power parameter (p) of 2 provided relatively low value , i.e., only 15% for Labanan, East Kalimantan Province and 17% for Lamandau, Kota Wringing Barat Central Kalimantan Province. In general, IDW interpolation method provided better results than the Kriging, where the Kriging method provided MD(%) of about 27% and 21% for Lamandau and Labanan sites, respectively
The Existing Condition of Mangrove Region of Avicenia marina, Its: Distribution and Functional Transformation
Get PDFMangrove ecosystem existence is important for environment and other organisms because of its ecological and economical values, so that management and preservation of mangrove ecosystem are needed. The purpose of this research was to determine the existing condition of mangrove, both its distribution and its functional transformation in Indah Kapuk Coastal Area. Avicennia marina becomes important as wave attenuation, a form of abrasion antidote. Transect-Square and Spot-Check methods were used to determine the existing condition of A.marina mangrove forests. Autocad program, coordinate converter, Google Earth, Google Map, and Arc View were applied in process of making mangrove distribution map. In western of research location exactly at Station 1 and Station 2, the density value of mangrove was 450 and 825 tree ha-1, respectively with sparse category because they were contaminated by waste and litter. In eastern of research location namely Station 3, Station 4, and Station 5 the mangroves grow well with density value of 650 (sparse), 1,500 (very dense), and 1,200 tree ha-1 (fair), respectively, eventhough the contamination still happened. The mangrove forests around the stations do not function as wave attenuation because there were many waterfront constructions which have replaced the function of mangrove forests to damp the wave. In short, it can be stated that the mangrove\u27s function has changed in a case of wave attenuation. The function of mangrove forests is not determined by mangrove forest density but it is determined by mangrove\u27s free position
Hyper Spectral Remote Sensing of Tropical and Sub-Tropical Forest (Editors: Margaret Kalacsca & G. Arturo Sances–Publisher: Azofeita CRC Press, Year 2008, 320 pages)
Get PDFIt is estimated that most of the problems in forestry associated with the spatial attributes. From the perspective of forest function that includes production, ecological, and social functions, the spatial aspects has always been a very important part. In Indonesia, the forestry areas is always dealing with very large areas which is mostly inaccessible due to limitation of roads, mountainous with steep slopes, cliffs, hills or wetland such as peat, swamp or marsh. This condition makes it difficult to collect the data in quick manner comprehensively with low cost. Veronique et al. (2012) recognized that remote technology may provide objective, practical and cost-effective solution. Currently, one of the most reliable data source that can be repetitively acquired with a unique and consistent traits are those derived from satellite imageries. It had been known that since the 1990s, earth resources remote sensing sensor is progressively developed either with finer spatial resolution, higher spectral resolution, more frequent revisit or wider dynamic range. The advent of high spectral resolution (e.g. hyperspectral) is quite challenging and prospectively gives a significant contribution, especially in forest management with higher level of detailed information. Without having adequate spatial information supported by strong scientific arguments, the forestry sector will be persistently pressured by many other sectors
Harvesting of Non-timber Forest Products by the Local Communities in Mount Halimun-Salak National Park, West Java, Indonesia
No full textLocal communities around the forest need to be involved in securing the sustainability of Mount Halimun Salak National Park (MHSNP), for example through the utilization of non-timber forest products (NTFPs) such as flora in the utilization zone. This research was aimed to provide data and information about 3 kinds of vegetation producing resin (Pinus merkusii, Agathis dammara, and Hevea brasiliensis) and the harvesting NTFPs by the community in the forest vicinity. The research was conducted in MHSNP, and data were analyzed through quantitative-descriptive. The survey method was employed in the study through interviews of respondents using structured questionnaires. This study revealed that the vegetations at the stage of tree comprised of the following: (1) Agathis dammara (damar) with Importance Value Index (IVI) of 276.15% and density of 452 trees ha-1, (2) Pinus merkusii (pine) trees with IVI of 300.0% and density of 552 trees ha-1, and (3) Hevea brasiliensis (rubber) trees with IVI of 217.42% and density of 85 trees ha-1. Pine, damar, and rubber sap tapping afforded contribution in 59.18, 4.41, and 60.71%, respectively of the total household incomes. Community involvement in the collection of NTFPs in national parks implicated to the increasing of the forest communities revenue and the forests will be maintained since public can get benefits from forest resources. Forest management should be directed as a producer of NTFPs that can increase the economic income of forest communities with attention to ecological factors
Land Use Conversion and Soil Properties in a Lowland Tropical Landscape of Papua New Guinea
Get PDFLand use conversion affects natural soil processes and can potentially decrease soils productivity. A representative area was selected to study the effects of land use conversion in Unitech Campus, Southeastern lowlands of Papua New Guinea (PNG). Area selected for the study was once covered by tropical rainforest and has been subjected to various land use types over time. Representative soil samples were collected under 4 main land use types (secondary forest, plantation forest, grassland, and agricultural garden) at 2 depths (0-0.15 m and 0.15-0.30 m) with 3 replicates per land use. Soil bulk density, water infiltration rate, and cumulative water infiltration values were significantly greater (p < 0.05) under grasslands than under secondary and plantation forests. Among soil chemical properties, extractable potassium content and pH showed significant differences (p < 0.05) among the land uses, pH values increased upon conversion of forested lands to grassland or agricultural gardens. Conversion of secondary forests into grasslands or agricultural gardens leads to depletion of Bray\u27s phosphorus and extractable potassium. Tree-based land uses were optimum due to better nutrient cycling conditions and lower bulk density compared to grassland and agricultural garden despite the low pH conditions and lower water infiltration
Candlenut Tree Management on People Forest in Tanah Pinem Subdistrict, Dairi Regency, Indonesia
Get PDFCandlenut tree is one of the multipurpose tree species because almost all parts of the plant can be utilized. The candlenut trees grow and are distributed in all provinces of Indonesia. Tanah Pinem in Dairi Regency is one of the candlenut-producer area. The objectives of this study were to learn and describe the management of candlenut tree in Tanah Pinem Subdistrict. The research was conducted with survey method by collecting data in the field. Primary data were obtained through structured interviews, while secondary data were obtained from relevant institutions and previous researches. The data were analyzed and described to learn how the community manage the candlenut tree and the condition at that time. The results showed that the candlenut tree is one of the plants that are beneficial because it can be a source of income for the community and play a role in safeguarding the environmental conditions of Tanah Pinem subdistrict. However, the management of candlenut tree was not intensive. Area size and production of candlenut tree tended to decrease each year. About 90% of Tanah Pinem subdistrict topography are steep and very steep, and it is necessary to replant the land with trees such as candlenut to protect the land from erosion and landslide hazards
Arbuscular Mycorrhizal Fungi and Biochar Improved Early Growth of Neem (Melia azedarach Linn.) Seedling Under Greenhouse Conditions
Get PDFThe objective of this research was to determine the effect of biochar on the seedling quality index and growth of neem tree seedlings and arbuscular mycorrhizal fungi (AMF) development grown on ultisol soil medium. Two factors in completely randomised experimental design was conducted under green house conditions and Duncan Multiple Range Test was used to analyse the data. The results showed that neem seedling quality index was improved by interaction of AMF fungi and biochar amandment. The growth of neem seedling was significantly increased by interactions of arbuscular mycorrhizal fungi and biochar. The combination treatment of Glomus etunicatum and biochar 10% gave best results of height and diameter, and significantly increased by 712% and 303% respectively, as compared to control plant, while the combination treatment of Gigaspora margarita and biochar 10% gave the best result of shoot dry weight, and root dry weight and significantly increase by 4,547% and 6,957% as compared to control plant. The mycorrhizal root colonization was increased with increasing biochar added, but decreases when 15% of biochar was applied. N, P, and K uptake of 12 weeks neem seedling old was higher and significantly increased as compared to control plant
Biomass Estimation Using ALOS PALSAR for Identification of Lowland Forest Transition Ecosystem in Jambi Province
Get PDFThe accurate information derived from high accuracy of remote sensing imagery analyses coupled with field observation data are required to develop a sound forest management. The study is mainly emphasized on assessment of the capabilities of remote sensing imageries to identify ecosystem types within the transitional ecosystem. Since, the predominant transition ecosystems found within the study area were secondary forest, rubber jungle, rubber, oil palm plantation, and also other land cover such as mixed plantation and shrubs, therefore, the models developed were focused for those ecosystem types. Prior to any further analysis, this study was initiated to develop the biomass estimation model using 50 m resolution of ALOS PALSAR image in transition ecosystem, Jambi Province. Biomass models were developed by analyzing the relationship between backscatter magnitude and field biomass. Backscatter magnitude from 1 polarization images, namely HH, HV, and one additional band of ratio of HH/HV were analyzed simultaneously with field biomass. The best models established are AGB = 42,069 exp (0.510 HV) and AGB = 1,610 exp (-0.02 HV²) with R² of 52.3% and 50,8%, respectively. The models are then used to map out the biomass distribution within the transition ecosystem and to identify the factors affecting the magnitude of biomass content for all transition ecosystem types
Genetic Diversity of Eurycoma longifolia Jack Based on Random Amplified Polymorphic DNA Marker
Get PDFEurycoma longifolia Jack is one of the extensively exploited medicinal plants in Indonesia. The objectives of this study were to obtain information on genetic diversity and population genetic structure of E. longifolia to formulate effective conservation plan. RAPD marker was used to assess the genetic diversity of E. longifolia collected from 5 natural populations in Riau Province. A total of 25 plants were analyzed using 5 RAPD primers, which amplified produced 44 scored DNA bands. The mean observed number of alleles per locus (No), number of effective alleles (Ne), and percentage of polymorphic loci (PPL) of E. longifolia were 1.57, 1.34, and 56.80%, respectively. The degree of differentiation among populations of E. longifolia was 0.31 (Ht = 0.29; Hs = 0.20). The mean value of estimated gene flow among populations of E. longifolia was 1.11 individual per generation. The UPGMA dendogram formed 2 significant clusters. The first cluster consisted of Pelalawan and Kampar populations, while the second cluster was formed from Kuansing, Rohul, and Rohil population. The genetic diversity information in this study is very important to perform efficient conservation and effective future management of its genetic resources.
Double Dividend from Tariff Differentiation of Reforestation Fund
Get PDFDistortionary levy applied uniformly to all diameter classes of logs from logging natural forest can lead to inefficiencies; certain diameter should be left in the field because it is not economical to be used. Win-win or Pareto improving solution can be achieved if the government is more flexible. Social welfare is higher because of the waste that can be utilized to create employment, production and additional benefits for employers, as well as revenue for the state. Even if the levy rates are forced to zero for small-diameter timber, governments is actually not harmed at all because from the beginning the government does not get any revenue from small timber that is left in the field as waste. In scarcity situations of timber from natural forests, it is desirable if the government is considering differentiating charges in order to reduce or possibly eliminate the volume of waste generated by the levy. In general, tariff differentiation done in the form of higher tariffs for higher diameter logs. If possible, the lowest diameter limit of logs is forced down to its technical limits. That is, the processing tool that will determine how the minimum diameter logs can be processed profitably.Keywords: tariff differentiation, efficiency, timber utilization, government revenue, win-win solutionDOI: 10.7226/jtfm.19.2.16