An increase in the area of unthinned planted forests is a major issue in Japan, and incomplete record-keeping means that a method for detecting unthinned stands is required. An important indicator of unthinned stands is stand density. In this study, we compared two stand density estimation methods, the discrete Fourier transform method and the local maximum (LM) filtering method, using simulated very high resolution satellite imagery. Evenaged Japanese cedar (Cryptomeria japonica) stands were modeled. Trees were positioned as though planted in a lattice pattern typical of these forests in Japan. The discrete Fourier transform method was more accurate than LM filtering and was stable over a range of stand densities, whereas the accuracy of LM filtering was sensitive to stand density and calculation conditions. Hence, the discrete Fourier transform was superior to LM filtering to estimate even-aged coniferous stand density.

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The Afforestation and Reforestation project activity under the Clean Development Mechanism (A/R CDM) is one of the policies set under the Kyoto Protocol. A/R CDM is to remove greenhouse gases by the afforestation or reforestation project in developing countries and has some specific features: non-permanency, uncertainty, and longterm. The introduction of the new policy targeted on the sink sector, the Reducing Emissions from Deforestation and Forest Degradation in developing countries (REDD), is considered in a next framework starting from 2013. REDD will give positive incentives for the reducing emissions from deforestation and forest degradation. The purpose of this study is focusing on proposal for the promotion of REDD, based on the analysis of the advantages and disadvantages of A/R CDM. To analyze the issues of A/R CDM, this paper especially focused on two stakeholders, project participants and host countries. Project participants regard A/R CDM (and REDD) as "business" and host countries consider them as "development policy." It is often said that much more discussion on implementation of REDD should be done based on the lessons from A/R CDM, but there have been no studies on sorting out problems especially concerned with A/R CDM, and on discussing how to reflect the lessons from A/R CDM to REDD. The research results showed that while A/R CDM had some innovative advantages such as giving financial incentives for the carbon sequestration function of a forest and helping to attain Sustainable Forest Management, there were many problems from the both viewpoints of "business" and "development policy," i.e. complex rules, low profitability, long-term corporation risk, and low priority for many countries. These results lead to the conclusion that there are restrictions and barriers to promote A/R CDM under the present rules and support systems. The recommendations for REDD are as follows; REDD is environmentally-sound and can be evaluated as a good system to contribute the multilateral functions of forest and local job-creation on forest management and conservation, but has disadvantages to restrict all "activities leading to the destruction of forests." The project scale of REDD would be much larger than that of A/R CDM, so that consideration on social aspect would be more significant. It is desirable to make the rules of REDD easy to use and understand for both developed and developing countries, to decrease the long-term corporation risks by structuring the partnership among stakeholders, and so on.

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We propose a new multiple-criteria decision-support (MCDS) system to consider the optimum area distribution and spatial layouts of forest types in forest zoning. We formulated a new index (W') that considers social demand for forests, potential capacities of forests and functional diversity of forests. Area distribution of each forest type (e.g. timber production, ecosystem preservation) was considered by maximising the index (W') using the Lagrange multiplier method. We dealt with the spatial layouts of the forest types by applying 0-1 integer programming. The applicability of the new MCDS system was validated through a case study at a national forest in Fukushima Prefecture, Japan. The following forest types were considered in the case study: timber production, water conservation, soil conservation, recreational land use and ecosystem preservation. The social demand for each forest type was quantitatively evaluated by an opinion poll. Potential capacities were assessed for each subcompartment using an existing index, regression analysis and valuation standards. We compared results derived from the index W' with results from six other methods. These methods were derived from combinations of the terms included in W'. The results from the new index were the most balanced and had relatively high scores for each item (social demand, potential capacity, functional diversity). The sum total of the scores was highest for the new index amongst all the methods. Each forest type was allocated adequately by integer programming. Thus, we concluded that the new MCDS system provides the most suitable area distribution and spatial layouts of the different forest types, taking account of both aspects of social demand and potential capacity of forest stands.

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Information on tree and stand growth is essential to ensure sustained timber yield in tropical natural forests, but very little is known about stand dynamics of tropical seasonal forests, especially in the mainland Southeast Asia. Stand dynamics of seasonal evergreen forest in central Cambodia were estimated from 20 sample plots measured in 1998 and 2003. Data for all trees with diameter at breast height (DBH)≧10cm and for commercial species DBH≧10cm or DBH≧minimum diameter cutting limit (MDCL) were evaluated. In 1998, 67 species, of which 19 were commercial trees with DBH≧MDCL, were found at tree densities of 544.5 and 23.4 trees/ha, basal areas of 23.8 and 6.3m^2/ha, and stem volumes of 192.9 and 64.3m^3/ha. The mean diameter increment between 1998 and 2003 was 0.33 for all species and 0.32cm for commercial species; mean mortality rates were 2.4% and 0.5%, mean recruitment rates were 2.5% and 1.4% and volume increments were 1.09 and 0.86m^3/ha. These values are similar to those reported from tropical rain forests in Amazon and Southeast Asia. Estimated volume increment (0.86m^3/ha/year) for commercial trees with DBH≧MDCL was significantly larger than the figure (0.33m^3/ha/year) previously used in Cambodian management systems.

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