Characteristics of parameters in power equation (r=az^b where r is the crown radius (m) at a given distance z (m) from the tree apex, and a and b are parameters) for representing the sunny crown profile were examined for Hinoki cypress (Chamaecyparis obtusa ENDL.). Three hypothetical models were constructed; Model 1: the values of a and b are unique for each tree, Model 2: the value of b is common to all trees, Model 3: the values of a and b are common to all trees. The three models were compared using AKAIKE'S information criterion (AIC) and root mean squared error (RMSE). Data were obtained from 112 sample trees selected in six pure stands of even-aged Hinoki cypress. Model 3 was inferior to the other two models in terms of AIC and RMSE. Model 2 was superior to Model 1 in terms of AIC. Although Model 2 gave a larger value of RMSE than that of Model 1, the difference was only 0.006m. When the profile of the sunny crown of a Hinoki cypress tree is represented by the power equation, we can assume that parameter b is invariant between trees and that parameter a varies from tree-to-tree.

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The function of the forest as a carbon sink is now a growing concern worldwide and there is a need to accurately estimate the forest biomass. A method was developed for estimating the stem weight based on the volume-density of stem measured by soft X-ray densitometry and the stem volume estimated by morphological analysis. The volume of log segment at each height and in each year was calculated using a formula for cone trapezoid, and the dry weight was calculated by multiplying the volume by the volume-density. These calculations were made using the application program [Stem Density Analyzer (SDA)] operating on Microsoft Windows-XP. The sample tree for analysis was chosen from the sample trees in the secondary breech forest at Kaminagawa Experimental Forest, Yamagata University. The cross sectioned wood disks were obtained from the stem at 1-m intervals. After drying, they were photographed with the soft X-ray together with the standard absorber for calculating volume-density. This film was scanned with a permeation-type image scanner, and the image data were analyzed with WinDENDRO. The annual growth in wood volume and dry weight increased year by year, but the growth in 1965 and 1995 was extremely poor. In the 82-year-old tree, the sum of each annual growth in dry weight was 441kg, and the amount of carbon estimated by multiplying a carbon ratio 0.5 was 220kg. The amount of carbon stored in the stems can be estimated precisely by calculating the weight of stems in each diameter class using this new method.

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To make fundamental information regarding wood quality for forest planning of teak (Tectona grandis L.), the variation of wood density, a reliable index of wood quality, were investigated. Six teak trees were sampled from two districts, Sylhet and Rangamati in Bangladesh. Wood density was measured by soft X-ray densitometry. Wood density remained more or less constant from pith to bark within individual trees, but varied between the two sites. Tissue proportions (Fiber, vessel, parenchyma and ray) varied conspicuously in narrower rings but were more stable in rings wider than 2mm. Vessel proportion was negatively and ray proportion was positively correlated with wood density. Ray proportions are considered to be tree specific and under genetic control. When planning to produce quality teak of higher wood density, proper site selection is the first and most important step. From the standpoint of uniformity and higher wood density, it is advisable to grow teak maintaining the ring width above 2mm and selecting trees with higher ray proportions for improving wood density. In teak, the differences in wood density between juvenile wood and mature wood were small. It is estimated that wood density is not affected by initial radial growth, consequently not affected by initial spacing.

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This study aims to categorize the approaches of four projects which were analyzed and verified by two cut ends; 1) the Construction of Participatory Framework (CPF) to establish adequate rules and good organization, and 2) the Building of Farmers Capacity (BFC) to enhance farmers' capacity in technical and financial phases of their groups' activities. It was possible to classify the four project approaches utilizing results of semi-structured interview survey with key informants about the support strategies and the contents of support from projects to farmers groups in this study. It was confirmed that Triple C (the Sustainable Rural Development Project in the Provinces of Cocle, Colon and Panama), RSEN (The Selective Reforestation with Native Species), and PROCCAPA (the Panama Canal Watershed Conservation Project) were classified with the New Paradigm approach emphasizing people but MARENA (the Management of Natural Resources Project) was classified with the Old Paradigm approach which did not consider BFC. Triple C was classified as a Financial Emphasized Type, and RSEN and PROCCAPA were determined to be Technical Emphasized Types. According to the differences in the countermeasures for the lack of income generation to farmers, RSEN has been classified with Payment Approach and PROCCAPA has been classified Communication Approach. In the next study, this classification resulted through the scoring will be from the view point of farmers for verifying which approach promotes farmers participation more or which approach propels farmers' activities more effectively in order to contribute to the suitable design of future projects for sustainable management of natural resources.

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We present two models of log-linear equations for biomass estimation in planted stands of 3- to 10-year-old Acacia mangium Willd. trees, using destructive sampling data of 59 trees in West Java, Indonesia. The log-linear equations include parameters for individual leaf, branch, stem, aboveground, belowground (root), and total biomass. Average annual increments of stand-level biomass were estimated at 7.77 to 10.09t ha^-1 y^-1 (model A) and at 7.91 to 10.27t ha^-1 y^-1 (model B), with the largest values in the 5-year-old stand. Following the methodology presented by IPCC National Greenhouse Gas Inventories Programme, we calculated basic wood density (D), biomass expansion factors (BEF), and root-to-shoot ratios (R) of the study stands. The value of D increased significantly as stand age increased from 3 to 8 years, but did not significantly differ between 8- and 10-year-old stands. The value of BEF did not differ among the 3- to 8-year-old stands (average 1.332) and decreased to 1.180 in the 10-year-old stand. The values of R increased significantly with stand age, from 0.157 to 0.190. The BEF values of A. mangium in this study were smaller than the default values for the tropical broad-leaf forest type (dbh>10cm) given by IPCC (mean, 3.4; range, 2.0-9.0). Because many factors may affect the parameter values of log-linear equations and D, BEF, and R for biomass estimation, the equations and values provided in this study are only applicable to A. mangium forests growing under comparable climatic, stand age, forest management conditions.

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Teak (Tectona grandis) is one of the royal hardwood timbers due to its mellow color, decorative grain, nice texture and odor. A huge demand for the species exists all over the globe. As the supply of teak timber from natural forests is low, hence a plenty of teak plantation is being raised to meet the supply. Financial analysis helps to find out a viable investment option clarifying optimal return scenario. There is a paucity of data on actual yield obtained at harvest of teak in Bangladesh. Limited works on growth and yield have been reported so far in this regard. This study clarifies the investment option on teak plantation in Bangladesh through historical trend analysis, model development and proper valuation techniques. From the findings of the study, it is found that quantitatively teak plantation raised in the past was profitable, currently it is profitable and it will remain profitable in future as well. However, there are risk and uncertainties in any investment especially in long term forestry investment the risks and uncertainties are very high. Probable risks options are identified and how much these risks are sensitive to the results also quantified for this study. It is expected that the findings of the study will have a positive contribution to the professionals and researchers around the world dealing with teak.

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