The key task for forest planner is to describe the expected production potentials of forest, and to allocate the forest area to produce the timbers and services that are wanted. One of the most important decision that a forest owner must make is to determine whether a forest stand should be cut or reserved or when it should be cut in accordance with the estimation of its financial maturity period with the maximization of the total net present value of the whole forestry stand. Stochastic programming is the study of practical procedures for decision making under presence of uncertainties and risks. This paper aims to describe an approach for timber harvest scheduling and optimization of forest stands retention period by the considering of uncertainties and risks. The model is based on the expectation variance (E-V) criteria. The method is based on the combined use of a network planning system and a quadratic programming that generates treatments schedules for forest stands and selects optimal schedule combination. The forest planning system consists of two principal parts : optimization and simulation. In the simulation the future development of stands is predicted and a large number of possible treatments schedules are generated for each stands. The simulation also produces information on the results attained if the treatment schedule is applied. This model can therefore furnish more effective information on the long term forest management decision making of forest owners.

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In this study we conducted a comparison among the conventional methods of calculating mean and variance of felling age (MVF) and examined the implication of their use on forest planning such as setting of a standard felling age and yield projection by the Gentan probability (GP). We used the data of planted forest areas and their harvested areas on a national scale in 1990 and applied the following five methods to calculate MVF using the weights of ; 1. harvested areas, 2. felling probabilities, 3a. observed GPs, 3b. GPs estimated by the censored sample method and 3c. GPs estimated by the maximum likelihood method. As a result MVFs became smaller in the methods 1, 2 and 3a than 3b and 3c. When we employed MVF as a standard felling age, the difference between the expected average harvesting volume and the target harvesting volume by the Forestry Agency of Japan became smallest in the method 3c, so that it seemed effective to apply the mean of felling age by this method for a standard felling age. Furthermore in the case of yield projection using GP, both fitness of estimated harvesting areas to observed ones and realization of yield projection in near future were best in the method 3c, so that it seemed effective to estimate GPs by this method for yield projection.

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In China, forest management have mainly performed in the natural forest. The forest managers are imposed tax and various cost burdens, even the mechanism is different from the income tax system, so the load of the forest managers is high. Today, forest policy is approaching to the turning point that the natural forest should be protected and forest management should be mainly performed in the plantation and promotes participation from each social sector to bring up plantation in China. The taxation system in China has become the main factor which hinders the spread of forest management and the development of the silviculture, it is accompanied by the cause of the expanding social problem and illegal action in forested area. Therefore, it is necessary to review the taxation and cost burden system to have sufficiently considered the characteristic of the forest management in China. As a result, we think the system that the forest manager can keep their life and forest management in future and the Nation can get a tax income is appling the deducting tax rate and the 10th power of 10 separation system. Moreover, it found that the forest manager must have forest area at least equal to or more than 2ha.

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In order to establish forests with multiple functions and develop an excellent relationship between 21^<st> century man and the resource, it is necessary to consider this relationship since after the 1949 formation of New China. In this study, Shenyang forests were taken as and example and investigated to clarify the features and problems of the forest development process since that time. When considering the forest development process of Shenyang, the shift from weighting economic forestry to that of multiple use forestry can be seen. However, recognizable existing problems include insufficient forestry legislation, frequently changing, inconsistent forestry policies over time, and community forestry practices system set-up and other issues. From this work, it can be understood that a stead honest effort to facilitate a shift towards sustainable forestry practices is required.

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This is a case study of the management of Baoshan ecological national forest farm for welfare-supporting ecosystem services. Its aims are to demonstrate the specific problems of the designated management of ecological national forest farm for the public's interest via the examination of inside data and interviews with the people concerned, with regard to the financial management of the national forest farm, and to establish basic future directions for financial policies for the management of ecological national forest farms for welfare-supporting ecosystem services. The findings show that the actual business processes and objectives of the management had to be radically changed due to a shortage of funds, in spite of the formal establishment of Compensation Funds for the Protection of National Forests for Welfare-Supporting Ecosystem Services in 2004. Furthermore, the current standards for ecological compensation do not meet the needs of the ecological national forest farm at all. Accordingly, for the ecological national forest farm whose business objective is to minimize the value of ecosystem services of the forests, it is difficult to manage them by means of self-financing based on independent accounting, and therefore it is essential to provide government-sponsored financial assistance and ample funds for management.

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This study aimed to assess how the mixture type and the ratio of broad-leaved trees in mixed stands of coniferous and broad-leaved species affected the evaluation of a forest landscape. We created 8 montage pictures with various mixture types (single tree or group mixtures) and ratios of broad-leaved trees. The photos were evaluated by 155 college students using the semantic differential and the paired comparison methods. The results of factor analysis indicated that views of mixed stands are evaluated based on affinity, orderliness, refreshment and activity. Subjects most liked the broad-leaved stand, followed in order by single tree mixed, coniferous, and group mixed stands. In the mixed stands, the higher the ratio of broad-leaved trees, the better subjects liked that forest stand. The mixture type had a stronger effect on evaluating a forest landscape than did the ratio of broad-leaved trees. Subject characteristics such as sex or academic year did not greatly affect the forest landscape evaluations.

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This study used IKONOS "Geo" imagery to detect damage to pine stands caused by pine wilt disease. The study was conducted in pine stands on Mt. Tsukuba in Ibaraki Prefecture, Japan. 66 plots (10m × 10m each) were established in the study area, taking damage ratio into consideration ; all the trees were tallied and examined for damage. Ratios of damage, healthy pine trees, and hardwood trees were then calculated in terms of basal area. Pan-sharpened colour imagery and multi-spectral imagery were analysed, and normalised difference vegetation index (NDVI) values were calculated from the images. The relationship between the mean NDVI for pixels in the plots and the field-observed conditions in the plots was then examined. The damage ratio and the ratio of hardwood trees tended to decrease and the ratio of healthy pine trees tended to increase as the NDVI increased for the two imagery types. Moreover, to validate a prediction method, regression equations were derived from half of the plots and applied to the other half of the plots. The root mean square errors (RMSEs) of predicting the damage ratio and ratio of healthy pine trees from the NDVI were approximately 0.15 and 0.12, respectively, for the pan-sharpened imagery ; the RMSEs for the same two ratios were approximately 0.17 for the multi-spectral imagery.

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In the Nakatsu River basin (3,544ha) in the Tanzawa Mountains of Kanagawa Prefecture, Japan, we analyzed relationships between the residual tendency of the landslides that seen in 1947 and topographic factors using the "Quantification n" method. We classified the landslide areas into two types : a "revegetative" type, which had disappeared by 1993, and a "residual" type, which was still existing in 1993. In the analysis, elevation, azimuth, inclination, cross-sections of slopes and turning points of inclinations were employed as the topographic factors. As a result, the order of the partial correlation coefficients and ranges of the items was elevation > azimuth > turning points of inclinations > cross-section of slopes > inclination, with influence by elevation and azimuth particularly large. Residual tendency was mostly observed at 900m or more a.s.l., and increased with elevation. In azimuth, residual tendency was seen mostly in slopes facing S, SE and W. In slopes in high elevation regions, especially those facing S and SE, it appears that the residual landslide period became so long because invading plants on landslides were not established easily due to disturbance of the surface soil by freezing and melting. In such an area, it may be better to give priority to soil conservation in forest management, especially to promote the growth of the main types of vegetation in a natural forest.

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The thinning of sugi plantations has become an important policy issue for private forests in Kagoshima Prefecture. To help clarify the potential effects of thinning on forests, we evaluated the system yield table, SILKS, which can predict yields and simulate thinning based on the present condition of a stand. Furthermore, the model can reflect the management intentions of forestry engineers. The growth model used was based on a forest stand in Kagoshima Prefecture, and was derived by correlating stand density and yield. Inputs to the simulator included stand age, average height of dominant trees, and the stem number per hectare necessary for the ecosystem to function. After quantifying the quality of the stand, we simulated three different thinning methods and predicted the effect of each method on yield. These simulations provide forest owners with a visual depiction of the effects of thinning, thus leading to a better understanding of thinning management and easing forest management planning. The aim of SILKS is to provide as many prediction results as possible from little information. The system, which seems to satisfy the basic requirements for a yield table, should clarify the effects of thinning and help evaluate the economic merit of sugi plantations.

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This research examines the economic backwater region of North-West China. The aim is to identify what kind of changes have emerged in the management techniques of noubokurinka due to the entry of corporations into willow production and its usage. The methodology involved interviewing the noubokurinka of W village who produce willow regarding the desert plantations of Inner Mongolia. This region is typical of an area that has promoted its economy and at the same time desert plantations through the combination of enterprise and farming. Willow is one of the most prolific species of tree in desert areas as it is suitable for securing areas of sand and sand dunes. Up to now it was used as fuel or sold as raw material in craftwork and construction, but it was only ever harvested in small quantities with the majority left to run wild. Companies entered the market from 1999 onwards causing the use of this left-over product to rise dramatically and presenting willow plantation farmers with an opportunity for improving development. As a result, a new source of income became available during the winter months while the salary of noubokurinka simultaneously increased. Year by year the benefits became clear. However because harvest and plantation rely solely on manual labor, large scale management is no more than the accumulation of small scale management and there are none of the usual merits. In the future, mechanization will be essential to raise levels of efficiency at harvest time in order to realize sustainable development in desert regions. As well as simply collecting willow for use as raw material there needs to be growth of production via the creation of a system that increases added product value via techniques such as secondary processing.

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"The project of the development of fast-growing and high-yielding forest plantation in key areas" is one of the "Six Major Forestry Projects" promoting the development of the entire forestry in China, aimed at the development of the industrial aspect in forestry. Most of the target areas of this project are the farmlands in plain agriculture districts, and so the success of this project strongly depends on the business condition of the farmers of these lands. The objective of this paper is to clarify the actual conditions of farmers' business and to promote the project, by analyzing the forestry management of farmers in Village S, Henan province, which is located in the North China Plain. In this paper the following facts have become clear ; 1) farmers have anxiety about forestry management, and so they cannot actively invest lands, funds, and labors in this project ; 2) farmers are extremely unfamiliar with the technology of planting trees that ultimately become the main entity of this project ; and 3) the species of the planted trees are homogeneous and there are many single-species forests, and so it is anticipated that this homogeneity would impose adverse effects on the ecosystem conservation in plain agriculture districts and the sustainable development of plain forestry.

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This paper examines silvicultural systems that may reduce future labour requirements, focusing on old sugi Qapanese cedar) plantations and taking both the yield and workforce into consideration. A 65-year-old sugi plantation of the University of Tokyo Forest in Chichibu, Saitama Prefecture, Japan, was used as the model stand; the yield and the required workforce for a roation of the stand were predicted. The stand rotation age was set at 65 years for the clear-cutting system; 100, 120 and 150 years for long-rotation systems; and 80 and 100 years for multi-storied forest systems. A thinning simulation thinned the stand after 65 years by a thinning rate of 30% and 60% of the total number of trees for the long-rotation systems and by a thinning rate of 70% for the multi-storied forest systems. For the multi-storied forest systems, sugi seedlings were assumed to be underplanted just after thinning. Long-rotation systems except the 120- and 150-year rotation systems with thinning rates of 30% had higher yields per year than the clear-cutting system; compared with the clear-cutting system, all the long-rotation systems also had higher yields per worker. On the contrary, multi-storied forest systems had higher yields per year but lower yields per worker than the clear-cutting system. These results indicate that forests could be managed to maintain both yield and to reduce labour requirements by introducing long-rotation systems.

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The maturity and sustainability of plantation forests in Japan have not been confirmed yet partly because approximately half of the total plantation area still requires silvicultural operations such as thinning and partly because the amount of reforestation has decreased drastically in recent years. The purpose of this paper was to develop a method for assessing maturity and sustainability of forest resources based on two previously created methods by Nagumo and Shiraishi. Nagumo's method, which assesses in reference to the normal forest with the same rotation, was more likely to underestimate maturity due to the high requirements of sustainability. While Shiraishi's method was easy to use, but was not applicable to the forests with entirely uneven age-class distribution. We integrated these methods, and then provided the new method which was simple and informative. Using this, the plantation forests in Japan were proved to be mature enough and to be sustainable with 70-year rotation.

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We analyzed the growth patterns of pure even-aged plantations of four North American hardwood species, yellow poplar (Liriodendron tulipiferd), black birch (Betula lento), pin oak (Quercus palustris), and north catalpa (Catalpa speciosd), in Iwate Prefecture, Japan. Yellow poplar plantations showed more vigorous height growth than natural hardwood stands in high-quality sites in Iwate Prefecture. The periodic annual volume increase in all the plantations except those of black birch in 2004 exceeded the simultaneous mean annual volume increase. The stand volume of yellow poplar plantation with a planting density of 1000 trees/ha was 476 m^3/ha when the stand was 28 years old; this was 2.4-4.2 times as much as the stand volume of the other three species in plantations with planting densities of 1000-2500 trees/ha and ages of 28-31 years.

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Demand for using GPS receivers in the forest has been growing higher recently. However, effective use of GPS in the forest subjects to a few issues, namely (1) influence of topography on sky openness, (2) degradation of GPS signal by trees, and (3) handiness of GPS receiver in the forest. With the forthcoming GNSS and RNSS, and available GPS satellite forecasting, the influence of the topography should be reduced to some extent. Comparison of Bluetooth GPS receiver carrying highly sensitive SiRFstar III GPS chipset and conventional GPS receiver was carried out in the forest. It was found that highly sensitive GPS receiver is able to reduce GPS signal degradation problem significantly. Besides, cableless Bluetooth GPS receiver can be very handy for the use in the forest. So, even at the present moment, GPS is practical tool in the forest.

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