Changes in the world's climate may alter the state of forests across broad areas, through changes in tree species composition, tree productivity rates, and natural disturbance regimes. These potential changes may also have a cascading effect on associated environmental services, such water yield, wildlife habitat composition, and biodiversity. The location, extent, and magnitude of potential changes to the climate will vary according to current regional climatic conditions. For example, RAVINDRANATH et al. (2006) suggest that some areas of India will become wetter and warmer under one 100-year climate change scenario. This paper examines the issues facing forest planners in an era of climate change, and illustrates the challenges and opportunities for assessing climate change scenarios in forest planning efforts. For example, accounting for tree species physiology in forest planning would allow analysts to recognize that some tree species may be less able to adapt to changing conditions. And, adding socio-economic change projections (development and recreational opportunities) to the analysis of policies will further help one understand the potential impact of climate on biodiversity. These and other additional aspects of quantitative forest planning will enable land managers and decision-makers to think through the vulnerability of forests to changes in temperature, precipitation, and wind speed. In addition, forest plans may need to consider actions that will reduce forest fragmentation, conserve biologically important resources, and reduce the vulnerability of forests to the risks presented along with an assessment of traditional forestry concerns (sustainability of timber production, sustainability of multiple uses, and sustainability of ecosystems). Thus there seems to be a need to assess broad-scale forest management scenarios that minimize adverse impacts and vulnerability to the uncertainties associated with insect, disease, drought, windthrow, and wildfire. This type of planning process would need to account for changes in climatic variables and associated changes in disturbance regimes, and recognize that some forests may be more vulnerable during the adjustment period.

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Many forests of the Atlantic region of western Europe are plantations created in the last century after a long history of deforestation. These forests have high growth rates by European standards and support competitive wood using industries. However, in some countries of the region (Scotland, Wales) there is increasing pressure to diversify the forests to meet the requirements of multifunctional forestry, while in other areas (the Landes region of south-west France) recent severe storm damage raises the need to increase the resilience of plantations to future climate change. A range of silvicultural systems can be used to diversify plantation forests, but these will have different impacts on indicators of sustainability. The framework of Forest Management Alternatives (FMAs) developed in the EU Eforwood project spans the range of possible stand manipulation from no intervention in a long-term reserve to complete above-ground biomass removal in short rotation forestry. Using the example of a Sitka spruce stand in Scotland, we present the values of a range of economic, environmental, and social indicators associated with each FMA. Traditional plantation management practices based on planting a single species and patch clear felling are more attractive in economic terms than for ecosystem services. A favoured alternative of combined objective forestry using a range of species and smaller clearfelled areas is not as attractive in economic terms and produces only small gains in ecosystem services. A close-to-nature option produces greater recreational and biodiversity benefits, while being only marginally less economically viable than clearfelling, because the use of natural regeneration saves on restocking costs. Current policies and guidelines for adapting forests to climate change propose greater use of less intensive FMAs at the expense of traditional plantation management and we illustrate possible impacts of such scenarios on selected sustainability indicators. Future development of this framework will need to link growth models with predictions of stand vulnerability to abiotic and biotic risks to allow more rigorous examination of the effects of changes in the balance of FMAs upon sustainability indicators. We outline research challenges which need to be tackled to allow managers to devise and implement appropriate silvicultural strategies to adapt Atlantic forests to climate change.

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The area covered by tropical forests is rapidly shrinking, and local wood shortages, land degradation, biodiversity loss and global warming are been recognized as the main negative impacts. This paper review literature and examines the depletion of tropical forests and implemented prevention strategies and discusses the remaining challenges to protect and implications for actions to restore the forests. The tropical forests are disappearing by 0.18% per year at a rate of 32,000 ha per day falling global per capita forest area to 0.6 ha in 1990 and projecting less than 0.2 ha by 2020. The tropical forests have been over-exploited creating serious threat on the production of forest goods and services. Some of the major global strategies proposed and implemented during the last few decades to combat tropical forest depletion include Tropical Rainforest Campaign in 1975; straightforward protected areas approach in 1980s; community forestry approaches in 1980s; market-based forest management after 1986; Tropical Forests Action Plan in 1987; The forest policy of World Bank in 1991; the integrated conservation and development programs through "Earth Summit" in 1992; forest certification in 1993; Millennium Development Goals in 2000 and Kyoto Protocol. Major challenges remaining in protection of tropical forests are recognized as the shifting socio-economic conditions of the countries; globalized financial markets; the worldwide commodity boom; and wood based industrial promotions. Many community-based forestry management strategies have currently become inappropriate without considerable external support. Eco-certification has hampered by corruption and weak governance while Kyoto Protocol has been defeated for political reasons. The international agreements and conservation programs have to be coordinated by the establishment of appropriate mechanism for coordination, consultation, and collaboration to conserve tropical forests. Dialogues and education campaigns among scientific, industrial and conservation interests have become a vital importance to slow harmful forest depletion with industrialization trends. Food security oriented forestry strategies and multipurpose forestry programs could be able to supply forest services and products to meet changing social, economic and environmental circumstances. Community forest governance would promote the sustainability of forest management with growing array of stakeholders, changing to multi-centric structures, and differences in scales, goals and means of forest management.

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In Taiwan, the idea of ecotourism emerged in the 1980s when Taiwan's national parks began to provide educational tours and interpretation services for visitors. Since then, ecotourism has been a popular term for marketing tourism in national parks, forest stations, natural reserves and rural areas in Taiwan. The "Ecotourism White Paper" for Taiwan was completed by the National Council for Sustainable Development (NCSD) in 2004, in an attempt to provide more environmentally sound guidelines for ecotourism management. One of its key management strategies is to determine a "tourism carrying capacity" for each destination to prevent its environment from degradation. Therefore, it brings up the question of how the manager of an ecotourism destination can properly determine a carrying-capacity limit that would stand the test. To examine this issue, this paper briefly reviews some applications of tourism carrying capacity for forest recreation management in Taiwan, and then explores the inherent features of management problems in ecosystems as well as some strategies to deal with them. Lastly, the implications for the future applications of tourism carrying capacity in Taiwan's forests are discussed, and it ends in the conclusion that tourism carrying capacity should be tackled as a decision-making issue in ecosystem management. That is, tourism carrying capacity is a management action that should be evaluated over time, and it is not a fixed number to be determined.

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Forestry is facing new challenges due to, e.g. multiple needs and values of people and society, globalisation of markets and changing climate. To safeguard the benefits to current and future generations, governments have applied different means of regulation. In global markets, individual market players, such as forest owners, companies and consumers, seek their own benefits. Sometimes conflicts appear between governing and market behaviour. To close this gap, there is a shift towards new governance emphasising voluntary, community and market-based instruments such as certification, community forests or commercial values for ecosystem products and services. Consequently, there is a need for decision support for market players, such as forest owners, and policy support for governmental consumers of ecosystem products and services. Luckily, recent advances in science and technology make it possible to support complicated decision- and policymaking situations. The aim of this study was to illustrate how information and communication technology helps to connect mathematical modelling with multipurpose forest management. First, the methodology and implementation of the Finnish MELA system are presented as an example of knowledge transfer in practical forestry. Thereafter, a case study is used to illustrate how MELA can be linked with multisource national forest inventory (MS-NFI) data, a geographic information system (GIS) and web-based services to facilitate collaborative planning and social learning in the context of a local forestry programme.

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Timber-frame building is a symbol of Japan's "Culture of wood" which makes use of renewable natural resources for construction. We face the global issue of limited natural resources, it is to this Japanese tradition of timber-frame building that we should turn to in to guide us to an important future course. 90 percent of cultural buildings designated by Japanese government are made of wood. The purpose of this paper is to estimate total material amount for timber cultural buildings and the forest resources needed to maintain wooden cultural assets and to propose social systems in order to secure forest resource for long-term more than one hundred years. About 40 percent of building parts are commonly replaced and at times requiring complete dismantlement. Total material amount of timber cultural buildings for government-designated structures was estimated approximately 300,000 m^3, annually a volume of 2,220 m^3 in standing trees was needed to secure 600 m^3 of repair materials. The average amount of wood used per square meter in timber-framed cultural buildings is on the order of 0.5 m^3. This means that these structures fix about 10 times the carbon as ordinary forest. For society as a whole to support the maintenance of cultural assets, it is necessary to disperse these risks as much as possible. Additionally, technical support measures are needed for forest owners to grow high-quality, large-diameter trees, and measures are needed to effectively use and raise the market value of timber that is produced but is not suitable for cultural asset repairs. That makes it necessary to increase the building of large-dimensional timber structures using large-diameter timbers, thereby inducing change in the manner of timber construction so that large-diameter timbers are primary. This will make it possible to log plantation trees at larger diameters and provide for longer rotation cycles.

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Mitigation of climate change by forest carbon sequestration is one of the ecosystem services that will be taken into account in future forest planning. The potential capacity of forests to sequester carbon is determined by edaphic and climatic factors, but the actual carbon accumulation is highly controlled by management. The effects of the management practices on stand development are successfully analyzed with traditional stand simulators that rely on empirical data. One of the current challenges is to understand how ecosystem services, such as carbon sequestration and timber production, can be managed in the changing climate, i.e. under conditions of which there are no observations. The objective of this study was to investigate the responses of forest soil and vegetation to a climate change under different management scenarios ranging from intensive thinning to unmanaged stands. The responses of tree growth and forest carbon sequestration to changes in temperature and precipitation (+3℃ and +10%, respectively) under different management scenarios were investigated with a process-based forest model (PipeQual) which was combined to a soil decomposition model (ROMUL) and a soil water balance model. According to our simulations, the growth response of Norway spruce to increased temperature was positive. Carbon stocks of both vegetation and soil were increased with the changing climate in all the simulated management scenarios. In the changing climate decomposition of soil organic matter was accelerated, however, increased litter input resulting from enhanced growth of vegetation compensated this decrease. Intensively harvested stands had a decreased carbon stock in the vegetation, which resulted in low litter production and decline in soil carbon stock after thinnings. The simulations with the process-based forest growth and soil model can guide management by determining a sustainable level of biomass harvest.

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In this study we demonstrated the procedures for model estimation and prediction based on the nonlinear mixed model (NLMM) technique. Since the unequally spaced and unbalanced longitudinal data used to fit forest models are often correlated and unequally varied, generalized error structures were examined and compared to the independent and identically distributed (iid) structure. In addition, since the vast majority of forest models are developed to be used as predictive tools on new data once the model coefficients have been estimated, predictions from the fitted model with and without accounting for the generalized error structures were evaluated on both model fitting and independent model validation data sets. Results showed that, under the NLMM framework, the iid structure is a superior choice for addressing correlated and heteroscedastic errors, provided that the model is appropriate for the data. This outcome has important practical implications, as a simpler error structure can achieve better predictions than more complex structures. The theoretical and practical consequences of ignoring or accounting for the error structure in NLMM estimation and prediction are discussed.

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Forests provide many goods and services and the demands for quality information about forests are continuing to increase. These demands include detailed information about an increasing range of forest characteristics and resources - both wood and non-wood based - on small, nominated units of land. For example, Kyoto-type carbon credit schemes operating at a high tier, and therefore in the most valuable markets, require precise and unbiased estimation of carbon pools in forests at specific sub-hectare locations. Simultaneously, landscape-level management decisions, especially those related to biodiversity, may require information about stand characteristics and their spatial distribution over thousands of ha or km^2. Historical approaches for forest inventory were often classified into strategic/national, operational/regional or tactical/local scales to support management decisions at corresponding scales. However, recent trends of increased attention to the role of even individual forests in local and global economies and environments - evidenced by international conventions and agreements like the Montreal Agreement or Kyoto Protocol, and international monitoring of specific areas of deforestation and degradation - has reduced the usefulness of the strategic/operational/tactical separation. Strategic decisions made during international policy negotiations may significantly affect tactical or on ground decisions on specific forested lands, while conversely good but independent tactical decisions may put strategic management goals at risk. Disagreement amongst inventories at the various levels (e.g. where the sum of tactical inventories does not equal the strategic inventory) increases the probability for conflict between strategic and tactical management decisions. This paper summarises the framework used in the National Carbon Accounting System (NCAS) developed by the Commonwealth Government of Australia to support policy-development especially in relation to global climate change and forests. The framework allows for the integration of information captured through long-term satellite sensing, physiological and empirical modelling, field-based measurements and regional "text" information. Although policy-development is obviously at a "strategic" level, the framework is flexible enough to also provide information at sub-hectare levels and supports seamless tactical decision-making as well. The information provided supports Commonwealth policy development and this paper demonstrates how NCAS also provides valuable information for other management purposes ranging from tactical management of fuelwood and farm timbers at the scale of individual farm forests, through to landscape-level structural diversity and biodiversity management.

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Climate change and biological invasions are threats to healthy forest environments throughout the world. Some species that have previously caused only small-scale damage have now become serious pests, causing massive outbreaks and yield losses including in Scandinavia. The spatial scale of outbreaks and intensity of defoliation caused by the common pine sawfly (Diprion pini L.) can vary between years, due to fluctuation in population dynamics. The study area is situated in Ilomantsi, eastern Finland, where D. pini has caused vast needle losses in managed Scots pine stands. We aimed at developing an accurate and cost-efficient inventory method for insect damage, in which we compared stratified adaptive cluster sampling, random adaptive cluster sampling and simple random sampling. Stratified adaptive cluster sampling proved to be the most accurate method and was a promising candidate for inventorying and monitoring pest insect damage in the study. Adaptive cluster sampling is a promising method for inventorying and monitoring such phenomena when area does not remain constant all the time.

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The objective of this study was to assess the vulnerability of forest ecosystem to climate change in Korea using MAPSS-CENTURY (MC1) model, one of Dynamic Global Vegetation Models (DGVMs). Also, it was to suggest selected and concentrated adaptation strategies for local government on the basis of this assessment. For the MC1 simulation of past years (1971-2000), the climatic data was prepared by the Korea Meteorological Administration (KMA). In addition, for the future simulation, the Fifth-Generation NCAR/Penn State Mesoscale Model (MM5) coupling with atmosphere-ocean circulation model (ECHO-G) provided the future climatic data under the SRES (Special Report on Emission Scenario of IPCC) A1B scenarios. This study predicted the changes in vegetation distribution by climate change, and it analyzed the spatial and temporal variation of the Net Primary Production (NPP) and Soil Carbon Storage (SCS) using the MC1 model simulations. The vulnerability assessment of forest ecosystem can be divided into two categories; 1) the vulnerability of vegetation distribution and 2) the vulnerability of forest ecosystem function, such as the NPP and SCS. In addition, the sensitivity and adaption capacity were evaluated for each category. As results of the vulnerability assessment, relatively vulnerable areas were situated in the western coastal part and south eastern inland of Korea. Based on the spatial variation in vulnerability, we could suggest that the central and local governments need to prepare concentrated adaptation strategies for climate change based on the vulnerability assessment.

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Recently, several studies have shown relationships between tree radial growth and climatic factors. It is generally assumed in dendroclimatological studies that there exists relationship between tree radial growth and the climatic factors. In this study, we analyzed the relationship between tree radial growth of Pinus densiflora and climatic factors that had been collected from sample sites in central urban area, Seoul in Korea. Based on sensitivity analysis of radial growth using a variety of combinations of independent variables, temperature has a positive effect on radial growth. The standard growth appeared better in the north and south aspects where the mean temperature was higher than other aspects. This study also indicated that spatial autocorrelation existed in standard growth with the range of 250m, indicating thatthere exist spatial differences in tree growth due to micro climatic and topographical variability. This result can be used to develop accurate regional process based model for reasonable management of urban forest.

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In this study, Pinus parviflora var. pentaphylla trees from four ridges (sites) on Mount Gassan in Yamagata Prefecture were sampled for tree-ring analysis. Two cores were collected from each of the 32 individuals sampled. After confirming the synchronization of tree-ring-width fluctuations within each site and among sites, correlation coefficients were calculated between tree-ring-width fluctuations and monthly climate data for precipitation, snowfall, daylight duration, and average temperature. t-values of the synchronization of tree-ring width among sites were higher than 3.46, indicating a significant correlation at the 0.1% level. Synchrony was not significantly different among sites. The range of synchronization was estimated to be within a radius of 14 km. The correlation coefficients between the tree-ring-width index and meteorological data for the previous year in December, January snowfall, and April temperature were significant at the 1% level. Our results suggest that P. parviflora var. pentaphylla trees from mountain ridges provide reliable information on past climate events and are thus suitable for assessing dendroclimatology.

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The development of empirical biomass models has gained a great deal of attention during recent decades. These models have been constructed to facilitate the quantification of forest biomass and carbon sequestration benefits, but few empirical models exist for estimating the stand biomass of teak (Tectona grandis L.f.) plantations. This study therefore sought to develop stand-level biomass models that use minimum input data for teak plantations in Central Java, Indonesia. Stand biomass and other stand variables were derived from forest inventory data in Balo (Kebonharjo, Central Java). We used linear and nonlinear regression to develop four types of biomass models: volume to biomass, basal area to biomass, age to biomass, and age and basal area to biomass. These models were then validated using an independent data set. Results indicated that teak stand biomass was accurately estimated using the volume-to-biomass model. In addition, while the accuracy of the age and basal area-to-biomass model was comparable to that of the volume-to-biomass model, the basal area-to-biomass and age-to-biomass models were less accurate. Depending on the availability of input data, at least one of these models will be appropriate for estimating teak stand biomass. Thus, these models should prove quite valuable in supporting the multipurpose management of teak plantations in Java.

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Carbon sequestration by plantation forests depends on the site conditions and silvicultural system used. This study estimated the spatial distribution of carbon sequestration by sugi (Cryptomeria japonica) plantations in a study area according to site quality and thinning regime. The study area was the University of Tokyo Forest in Chiba, which is located on the southern Boso Peninsula, Japan. Site index curves were created from height measurements in sugi plantation experimental plots. Sixty-five sampling points were located in sugi plantations, and the heights of three to five dominant trees around each sample point were measured. The site index was calculated for each sampling point, and the average height at 60 years of age was estimated from the average height at each sampling point using the site index curves. Site factors were calculated from a digital elevation model (DEM) in a geographic information system (GIS). Discriminant functions were developed from five site factors: slope, shaded relief, distance from a ridge, plan curvature, and the wetness index. The correctness rate was 60%. In addition, stand growth was predicted for each site quality using LYCS ver. 2.32 under low thinning at frequencies of 1, 2, 3, and 5 times. Carbon sequestration was estimated from the growth of stand volume multiplied by the basic density, biomass expansion factors, ratio of total biomass to aboveground biomass, and carbon fraction. The estimated carbon storage and sequestration for the study area were mapped using GIS according to the site quality estimated from the five site factors and specified thinning regimes. The average carbon storage per hectare peaked at a thinning frequency of one. Thinning during the young stage increased carbon storage, although frequent and strong thinning regimes decreased carbon storage. The average carbon sequestration per hectare increased with thinning frequency because more frequent thinning leads to faster growth just after thinning in more stands. These maps enabled us to understand the change in carbon storage and sequestration over the study area according to the chosen silvicultural system.

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The purpose of this study was to conduct a yield prediction from 2001 to 2050 on a national level by developing the Gentan probability-based model that combined yields of 47 prefectures. First, the Gentan probabilities were estimated for the 22 prefectures that had reliable harvesting data by the maximum likelihood method. Second, these prefectures were clustered into 3 groups based on the estimated Gentan probability patterns, and then the synthesized Gentan probabilities were estimated for each cluster from the aggregated stand areas and harvested areas of prefectures which belonged to the same cluster. Third, the other 25 prefectures without reliable harvesting data were classified into the preceding 3 clusters by discriminant analysis with socioeconomic explanatory variables. Fourth, harvesting volume were calculated for each prefecture based on the estimated Gentan probabilities: The former 22 prefectures employed the Gentan probabilities derived from their own harvesting data while the latter 25 prefectures employed the synthesized Gentan probabilities corresponding to their cluster number classified. Finally, a yield prediction was conducted from 2001 to 2050 based on the 5 scenarios that increased the means and standard deviations of Gentan probabilities in 47 prefectures by -10%, -5%, 0%, 5% and 10% every 5 years during the prediction periods. The results showed that harvesting areas decreased as the means and standard deviations got raised, and that the scenario of 0% increase brought about moderate result. To actualize this scenario, a standard rotation age in the Regional Management Plan should be raised 5-7% every 5 years for next 50 years.

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Selection forest is a forest managed with the uneven-aged silvicultural system, in which trees are removed individually from a large area periodically. Selection system has been used to manage natural forests in Hokkaido, northern Japan. This study demonstrated the characteristics of natural selection forests in central Hokkaido. A case analysis was conducted at the University of Tokyo (UT) Hokkaido Forest to closely examine the structure and geography of selection stands. We used a total of 1,382 sample plots that had established in selection stands during 1996-2005 and the spatial information on stand classification with 10-m grid digital elevation model. We calculated the mean dominance and density of trees with DBH&ge;5 cm, which were 30.7 m^2 ha^<-1> and 792 individuals ha^<-1>, respectively. Juveniles (Height&ge;1.3 m and DBH<5 cm) had a mean density of 561 individuals ha^<-1>. An asymmetric and peaked distribution was observed in tree and juvenile density. The predominant tree species included Sakhalin fir (Abies sachalinensis), Yezo spruce (Picea jezoensis), Japanese linden (Tilia japonica), and painted maple (Acer mono). An inverse J-shaped diameter distribution was maintained in tree density. Selection stands were mostly located on an area between 300-600 m a.s.l..

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The aim of this research was to develop an indicator of genetic diversity for three major conifer species, Abies sachalinensis, Picea jezoensis and Picea glehnii, and to evaluate landscape-level genetic diversity in the Toyohira River basin, of Hokkaido, Japan. Biodiversity is a key factor for sustainable forest management and often defined at three levels, ecosystem of region, species and genes. Ecosystem and species levels of diversity can be evaluated at the landscape level based on ground survey and spatial information. On the other hand, genetic diversity at the landscape level is rather difficult to assess due to the size of the distribution area and because ground surveys and direct measurements of genetic difference are needed to clarify biogeographical characteristics. For this study, we first defined a genetically homogeneous area. We then developed a genetic diversity indicator, "number of fathers," using forest register information. Finally, we evaluated the genetic diversity in our target basin. The results show that Abies sachalinensis and Picea jezoensis were widely distributed in their own "high diversity" genetic zone, whereas the high-diversity zone for Picea glehnii was distributed as islands. These results reflect biogeographic characteristics and show that the developed indicator for genetic diversity is appropriate for illustrating landscape-level genetic diversity in the Toyohira River basin.

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Crop damage caused by wildlife, including macaques, has become an increasingly serious problem in Japan. We focused on two Japanese macaque troops with adjacent home ranges. We calculated landscape indices of their habitats and measured differences in frequency of farmland invasion between the troops. Our objective was to determine the relationship between troop invasion frequency and landscape indices (size, shape, and configuration). Location data of the "Yonekura" and "Otsuki" troops were collected by radio telemetry from 2004 to 2006. The home range areas of the two troops were estimated using the Minimum Convex Polygon method. A land-cover map was acquired from remotely sensed imagery (ALOS/AVNIR-2). This map was classified into five landscape classes (forest, farmland, urban, grassland, and water). Troop home range areas were overlain on the land-cover map, and landscape patches included in home ranges were counted. To discern differences between troop habitats, the landscape index of each patch was calculated. Size, shape, and configuration of habitat were selected according to a previous study. A generalized linear mixed model was applied to identify environmental factors contributing to farmland invasion by the troops. We calculated the importance of the variables that contributed most to farmland invasion. The home range area of the Otsuki troop was larger than that of the Yonekura troop, and within the ranges, the ratio of farmland to home range and the ratio of urban land to home range were higher for the Otsuki troop. For each landscape index, a difference was found between the habitats of the two troops. In models of the two troops, distance between farmland and forest boundary and distance from a road were important factors. Moreover, the frequency of farmland invasion differed in distances from exclosure fences. Differences in farmland invasion between troops were attributable to differences in habitat landscape indices. The shape of the Otsuki troop habitat was relatively complex, increasing opportunities for macaques to come in contact with farmland. Our results show that it will become increasingly easy for Otsuki troop to invade farmland.

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Using the standard parameters of stand and logging conditions and incorporating cost reductions and discount rates, I estimated the financial yield under the soil-rent theory, present value of future profit (PVFP) model, and forest-rent theory. I observed the effects of cost-cuttings on shifts in the optimal cutting age and the range of acceptable cutting age caused by the simultaneous harvesting of adjacent conifer plantation stands in Japan. Under the forest-rent theory, the optimal cutting age was 110 years, which was the upper limit of the calculation. The lower limit of the range of acceptable cutting age was greater than 100 years under all assumptions. With simultaneous harvesting, the optimal cutting ages under all assumptions were within the acceptable ranges, and the acceptable range could be narrowed for PVFP. Shifts in the optimal cutting ages resulting from simultaneous harvesting were small compared to those caused by changing the discount rate and the rate of subsidies for planting and silvicultural operations. These results indicate that forest managers can decide on cutting age without being concerned about the dispersal of the current stand ages and the optimal cutting ages of adjacent stands.

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This study developed the method to extract production forests based on economic balances with considering regeneration expenses for sustainable forest management. This study defined production forests as forests where expected revenues at clear cutting surpassed all costs such as harvesting and regeneration expenses. These revenues and costs were estimated based on forest registration and GIS data. The study site was Kanuma Area of Tochigi Prefecture. From the results of the double log prices their level from 1981, this model could relatively accurately estimate a variety of revenues and costs according to log prices. According to the result on the current conditions with considering regeneration costs, only 1.93% was extracted as production forest candidates. Thus, the implication is that conducting sustainable forest management at cutting age, 60 years is difficult based on the current conditions in this area other than 1.93% stands. This could be the reason why 94% of the forests are classified as those intended for water and soil conservation although Kanuma area is one of the famous forestry areas in Tochigi Prefecture. This situation occurred due to low log prices and high costs. All costs on smaller areas, subsequently volumes of subcompartments were much more expensive than log prices of even Hinoki cypress because all costs included indirect costs which were almost all fixed costs, the smaller the areas, subsequently the volumes, the higher the costs. Therefore, it will be necessary to decrease all costs considerably by extending forestry-operation sites while merging small subcompartments. Moreover, estimations that involved cutting ages set at 80, 100, and 120 years were conducted while considering long-term rotation management. However, the percentage of production-forest candidates increased a little because there was no change in the quality of logs, subsequently log prices. This study did not consider effects of changing log prices along with log quality and some kinds of subsidies. Developing the forest-road networks and extending forestry-operation sites through the merger of small subcompartments should be also examined. The next study will analyze these effects and which factors have the ability to decrease costs.

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In this study, the forest road network planning method for combining the arborescent forest road network and the circular forest road network was examined, and the road network planning program was made. First, the developed planning method for the forest road network selected the target sub-compartment which had the most benefits among sub-compartments. The benefits were calculated from the species, forest ages, yield tables, and log prices. After selecting the target sub-compartment, it determined an attainment point that is a terminal point of the arborescent forest road in the target sub-compartment. The target attainment point was the point to which the total distance from all grids in the target sub-compartment was minimized. Also, it determined the route of the forest road from the existing road to the target sub-compartment, using the Dijkstra method to minimize earth-work costs, where the gradient of the forest road was below 60%. Afterwards, it checked the route of forest roads from the target attainment point along the contour line, using the Dijkstra method where the gradient of the forest roads was below 35%, to develop the circular network. The program repeated these processes until the density of forest road network reached a predefined value. The road network program was able to plan the forest road network with different numbers of circular networks with the same density of the forest road network by changing the search range of forest roads along the contour line. Then, the development of forest road network and the skidding/yarding efficiency were evaluated. As a result, the average skidding/yarding distance on the forest road network developed by the program was shorter than that of the actual forest road networks constructed by a forest owner; the average distance between attainment points was also shorter than that of the actual forest road networks. Therefore, the program could plan forest road networks on which skidding/yarding efficiency and traffic benefits were improved.

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In order to meet the needs of society's increasing demands for forest products in the coming years, sustainable forestry must become more efficient. Therefore, we propose to bring aerial and terrestrial survey technologies into the forest, as well as virtual production strategies, which are well-established in manufacturing. Precise position information of forest work machines and individual trees are necessary for a highly accurate navigation in the forest. As GPS does not provide the required accuracy, especially under a closed canopy, we propose a new localization approach based on a multi-sensor system. The approach will help to preserve the forest health while raising efficiency and enables applications based on highly accurate position information. The first part of this article gives a review on common localization strategies. The next part introduces the components of the sensor system in detail. In the third part the underlying principles are clarified and examples are given of how these are applied to new applications in forestry. The results are evaluated and compared to conventional measurement techniques.

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Stands of Cryptomeria japonica and Chamaecyparis obtusa have different functions: in particular, diversity of understory vegetation and prevention of soil erosion, but their distribution is not always delineated and distinguished on forest maps. This study investigated the relationship between parameters in the image segmentation procedure for high-resolution satellite data and generated object size in object-oriented classification, and distinguished objects of C. japonica and C. obtusa by means of discriminant analysis. Thirty-six sample plots were established in C. japonica and C. obtusa stands in the national forests of the Koisegawa watershed. QuickBird panchromatic and multispectral data was used for this study. Segmentation, which is the first step in object-oriented classification, was applied to the image data of the sample plots, and species were assigned to corresponding objects generated from the image segmentation. For these objects, the average and standard deviation of digital number for the four multispectral bands and panchromatic band and the Normalized Difference Vegetation Index (NDVI) were calculated within them. Discriminant analysis to distinguish C. japonica and C. obtusa was conducted using these twelve variables of average and standard deviation as independent variables. The correct distinction was made for 100% of C. japonica objects and 95.5% of C. obtusa objects. The results clarified that it was possible to distinguish C. japonica and C. obtusa patches using high-resolution satellite data.

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The purpose of this study was to outline the present pattern of forest cover and change in Thakurgaon, northern Bangladesh. Forest cover changes were identified and approximately delineated by remote sensing. Remote sensing technologies are used to monitor forests in many parts of the world. The availability of extensive and timely imagery from various satellite sensors can aid in identifying forest area and the rates and patterns of deforestation. We conducted a comprehensive assessment of forest cover changes in Thakurgaon from 2006 to 2008 using imagery from the Advanced Land-Observing Satellite (ALOS). Bangladesh is poor in forest resources, with approximately 14% forest cover in the country as a whole and only about 3% cover in the Thakurgaon area. Rapid population expansion has resulted in increased wood consumption and resource overexploitation that have degraded forest reserves. Near major population centers, large areas have been rapidly converted from forested to non-forested land. The most evident cause of forest loss is conversion of forest to agriculture, for both food and cash crop plantations. By analysis of ALOS imagery, we could clearly identify changes. The results can help foresters identify endangered areas and prioritize management. We found marked increases in forest area in places protected by local governments or private forest owners. Some cultivable land areas were converted into forest and open forest land, although these results may have been affected by cloud cover in the satellite imagery.

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High resolution satellite images of forests have a key role to play in natural resource management. We describe and evaluate a new analysis technique for 1- Identification of the juniper's tree crown 2- Estimating juniper forest density by counting trees per hectare, 3- Estimating vegetation indices. In this paper, we introduce a new means of analysis for counting trees, calculation of the vegetation index (VI) and comparison with tree numbers per hectare. Results showed linear regression models between the normalized difference vegetation index (NDVI), the soil adjusted vegetation index (SAVI), the optimized soil-adjusted vegetation index (OSAVI) and number of trees per hectare R^2=0.79, 0.79, 0.87, CV%=19.22, 19.27, 19.22 respectively. In addition, the linear regression of counting trees with the new analysis technique by TreeVaW software and trees measured by ALOS data (Avnir-2 and Prism) R^2=0.72 will be demonstrated. In this study, we have found a useful tool for counting trees in arid and semi-arid regions, thus enabling estimation of biomass and better decision making for natural resource managers in fields of environmental benefit.

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In the last decades, to cope with the reduction of forest resources and covers, models of community forest management have been considered to apply as a potential system in mountainous areas in Vietnam. There have been many trial models that were applied and are requiring an analysis of the real effects. This article aims at exploring features of the community forest management in terms of forest resources and benefit mechanisms, institutional arrangements and compromises of local people, and clarifying the community's response to this forest management model in Central Vietnam. By applied the multi-criteria analysis approach for the multi-use framework of community forest management, this research revealed that the flexible application in developing benefit sharing regimes based on the forest reserve and stable forest models has been applied as the initiative to give chances of getting benefits from forest resources to local people. Institutional structures as well as roles and responsibilities have also been developed and agreed significantly at the local communities. However, since the allocated forest is low reserves and quality, and inconsiderable capacity of products as to current needs of communities, the participation of those poor communities is still limited. Additionally, lack of detailed planning and orientation after forest allocation has restricted the realization of benefits from forest as well as communities' independence and self-management. Therefore, to solve the realization of benefits that helps to motivate the participation of local people in forest management, it is necessary to consider carefully and use flexibly the integrated analysis framework and solutions. Especially, the attention should be paid to establishment funds for forest protection and development activities within the first five years after forest allocated. At the same time, providing guideline documents and assistance for treating cases violated as well as applying simple sylviculture techniques are also needed.

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Wooden cultural buildings are a symbol of Japanese culture. It is necessary to secure a supply of large logs to maintain these important cultural buildings in perpetuity. Besides to having a large diameter and length, these logs need to have a high quality of wood. However, it is difficult to secure a permanent supply of such logs. That is because required large diameter and long materials logs are usually not offered at a customary timber-market. Prescribed conditions to maintain important cultural buildings are strict and require using the same building technique as well as using the same tree species of the same tree quality. That imposes a demand for the trees of the same kind, size and wood quality as it is used in existing wooden cultural buildings. Therefore, there is a need to conduct a research on the quantity of the demand and to investigate capability of forests to fulfill such demands. We need to secure a sufficient supply of required trees and to find out a present state of large sized trees. This paper presents our developed technique to estimate a standard size of standing trees which have served to produce a large-sized building material for wooden structures. We have taken a representative sample from published reports on Japan's cultural buildings built throughout Heian (794-1185) and Kamakura (1185-1333) period. Furthermore, in order to presume the size of saw-wood, we have measured logs at the warehouse and have calculated the width of sapwood. Moreover, in order to calculate the height and the relative taper-curve using a three-order equation, we have measured heights, DBH as well as diameters along the trunks of standing Japanese cypress trees growing at Kiso area of Japan. Finally, we have estimated standard sizes of standing trees which have served to produce a large-sized building material for wooden structures. Now, we have information on standard sizes of standing trees which have served to produce a large-sized building material for wooden structures. Furthermore, using our developed technique and measuring only the DBH, now we can assess a present state of standing trees being suitable for the maintenance of wooden cultural buildings. The standing trees being the most difficult to obtain were the trees of size used to build the 18 pillars of Nandaimon at Todaiji temple. These pillars have a size of 1 meter in diameter and 19.17 meters in length. We have estimated that the standing trees should have a DBH more than 150 cm to be of use in producing such large sized pillars. Even at Kiso area where a large-sized Japanese cypress trees still can be found, it is extremely difficult to secure a supply of trees having a DBH larger than 150 cm. Hereafter, the present state of large trees should be assessed. Furthermore, a relatively large forest area should be bequeathed for the purpose of securing a permanent supply of large-sized trees having a required good-quality. Our next tasks are to follow up the growth of the prospective trees in forests.

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Recently, forest education, which the Forest and Forestry Basic Act describes "promoting the use of forests for education", has been attracting attention. For its part, the Forestry Agency started to promote "Forest Environmental Education" and "Education for Wood Products Use". There are a wide variety of activities, but the actual types of activities in forests have not been understood. So sites in forests for forest education have not yet been considered. In order to gain a comprehensive understanding of the forests for forest education, outdoor and nature activities in forests were examined as actual activities of forest education. In this study, we analyzed the content of activities in forests and the places for activities through a questionnaire survey on outdoor nature activities in forests in Hachioji, Tokyo, Japan, and analyzed the relationship between the content of forest activities and places for activities. Due to the diversity of forest type and land use in this city, there should be many different type of forest activities. We sent various groups a questionnaire which were considered to be involved with forests activities, and then analyzed the contents of activities in forests, forest types and places for the forest activities through cross-tabulation. The survey started by asking whether any activities had been implemented, and if so, asking the details of the three main activities. We sent the questionnaire to 467 groups, of which 215 (46.0% of the total) responded in 2006. A total of 129 groups listed activities in forests (60.0% of the respondents). And 224 actual activities were recorded. We analyzed 209 activities implemented in Hachioji by 103 groups, without incomplete example data. The results of our investigation on the actual conditions revealed a wide variety of 13 kinds of forest activities. Every activity was carried out in all forests types, but zouki-bayashi was used most frequently. Regarding site type, public places such as parks were used most frequently. To consider the relationship between contents of activities and forests, forest activities were characterized mainly by the use of forest sites, based on the ownership and the need to obtain permission for use. Forest activities tended to use forest sites related forest use form: Use-type (a) with no change to the forest such as walking/hiking was implemented mainly in "open areas" that allowed public access. Use-type (b) with a direct impact on forests was implemented mainly in "closed areas" with restricted use. Use-type (c) was mainly implemented in specially designated facilities. Another activity was held in various places with little impact on forests. Use-type (a) was most common. In conclusion, we considered that the content of forest activities is closely related to the use of the forest; especially the impact on forests from forest activities is a major factor. If forestry works were more widespread, it would be necessary to keep forest places where direct impacts on forests in open areas were allowed. Furthermore, it should be necessary to analyze the impact of each kind of activity on forests.

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