One of the major problems involved in surveying vegetation cover in urban areas using satellite images is that there are many areas of vegetation which are smaller in size than the resolution of satellite data. By overlaying satellite images with corresponding vegetation maps, we examined the relationship between vegetation cover ratio and vegetation index pixel by pixel. It was found that as the vegetation cover ratio decreases, the difference between it and the vegetation index becomes increasingly more significant. Based on the average vegetation index, we estimated the area of vegetation and found that this method was more accurate than the more widely used method of supervised classification for estimating vegetation areas. This was because our method is capable of estimating areas in proportion to the mix of vegetation cover, that is, it is more suitable for estimation of actual vegetation cover in urban areas.

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This paper clarifies the current status of the cutting reporting system in Japan. This system was enacted as part of the Forest Law after the Second World War. Initially, a cutting permission system was introduced, and this was later changed to the current cutting reporting system. Recently, the percentage of forest owners filing cutting activities by the cutting reporting system has been low. As a result, several problems have occurred, for example, the forest resource database can not be updated. To determine the reasons why forest owners do not file the cutting reporting form, a questionnaire was conducted in July 1995, and responses were obtained from 666 forest owners and 33 forest advisors. It was found that: (1) The percentages of forest owners and forest advisors who are familiar with the cutting reporting system are 49.1% and 66.7%, respectively. Over 20% of both categories are not even aware of the existence of the system. (2) The percentages of forest owners and forest advisors who filed all cutting activities during the past five years were 12.2% and 5.0%, respectively. There were many forest owners who did not file cutting reports even though they were aware of the system. (3) The reasons why forest owners do not file the report are not only a lack of familiarity with the system and its requirements, but also erroneous or deliberate misinterpretation of the system, i.e., a cutting report is not required if cutting activities are small in size. (4) Of the forest advisors, 45.5% recognize the necessity of reporting cutting activities for the promotion of the local forestry program. The importance of the cutting reporting system and the possibility of promoting its use are discussed and six policy recommendations are presented. Most notably, increased publicity must be started as soon as possible.

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This report deals with yield tables of natural shii (Castanopsis spp.) stands for timber production developed using a stand density-control diagram. Since natural hardwood stands such as shii stands don't generally have normal diameter distributions, mean diameter doesn't give appropriate information about the numbers of trees. Median or upper-hinge diameter, however, give direct information about tree number for any distribution types. In the light of the discussions, the shii stand density-control diagram was improved by replacing equivalent mean diameter lines with equivalent upper hinge lines. Then management plans for timber production were discussed and a site index table was compiled. These led to the development of yield tables for different goals of timber production goals.

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The national park system of Japan was the first to integrate regulatory land use zoning within scenic areas that encompass a diversity of landownership patterns. This was because zoning regulation was the only practical way to establish national parks in a country lacking public land. The most influential factors determining the park and its zoning boundaries were land ownership and the regulation of forest management of 1933. 90% of proposed park lands was forested and often used for forestry. The boundaries of parks were determined after consideration of landownership: Public forests were preferred, and the restrictions governing private forests were relaxed in the case of inclusion. As a result, only 13% of the park lands were private when the twelve original parks were designated by 1936. As the majority of public land was national forest, the national park system of Japan was based on these forests as cores. This was due to following reasons. First, the national park policy could coexist with forestry when economic pressure was low and harvesting was not mechanized. Second, promoters of national parks were associated with forestry education, and sustainable forestry was popular issue among them. Third, case-study models like the American parks and the domestic Forest Law suggested that management of forested areas in the parks could continue. Thus, forestry was the real force behind the national park policy in Japan. Before the Second World War, influence of forestry on the national park policy was acceptable. However, as economic demands on forests increased after the War, easily manipulated forest landscape guidelines and double agency management made the forest areas in the national parks vulnerable to economic demands and jeopardized national park management.

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To illustrate the features of the post-war development of a large-scale forest business and its economic characteristics, this paper focuses on the relationships between technical developments in the management of man-made forests and forestry labor. It uses Hayami Forestry of Miyama-cho, Mie prefecture as a case study. Hayami Forestry, in the course of post-war development and while coping with the changes in the timber market, has continued establishing man-made forests, created a system of comprehensive forest management, and developed new employment conditions. Based upon developments in the production of good quality timber and the relative advantage of Japanese cypress prices in the timber market, the trend of long-rotation management began in the 1970's. In the 1990's, with the establishment of new labor and employment conditions, there were increased levels of employment of new young labors and at the same time, the mechanization of forestry entered a new phase.

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Since very early times Sri Lanka has had many forms of forestry practices including forest plantations. The British introduced modern plantation forestry in the 19th centry. Since then the plantation forestry sector has grown and legal and institutional frameworks have developed, although the total forest cover of the country has dwindled. Today forest plantations cover about 3% of the land area and comprise exotic as well as native tree species. Primarily they supplement the nation's timber and fuelwood needs. During the last decade several changes have taken place in the country's plantation forestry; (1) increased international funds, (2) increased awareness of forestry, (3) orientation toward the public (4) increased planting of indigenous trees and (5) a transition from government monopoly to a mix of state-owned and privately-owned plantations. For a sustainable future of forestry, forest plantations should be planned holistically, with consideration of alternative forestry practices, and the national land use, energy and timber utilization needs.

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The diameter at breast height (DBH)-tree height relationship for Japanese red pine (Pinus densiflora) in an extensive natural forest (27.86ha) was studied at the Kyushu University Forest in Miyazaki (UFM), southern Japan. DBH-height allometry and the shape of height distribution based on DBH class were analyzed using a generalized allometric equation and the Weibull distribution function, respectively, and a height estimation model based on DBH (HEMD) was constructed. The slope of the DBH-mean height curve at a forest level was steeper than that for Pinus densiflora stands at a plot level. The height distributions based on DBH class were positively-skewed and the degree of skewness was stronger at sizes <20cm and >50cm. HEMD described height distribution and DBH class-volume distribution well at a forest level. The effects of stand structure on size diversity and the DBH-height relationship of Pinus densiflora in the UFM were discussed.

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We compared sky factor, which is used in the field of architecture, and openness grade with measured relative illuminance. Sky factor and openness grade were measured on hemispherical photographs taken with an equidistant formula fisheye lens. The measurements were conducted under uniformly overcast skies at 20 points in a hinoki (Chamaecyparis obtusa) stand. Sky factor corresponded well with relative illuminance and the errors were ranged from -0.96 to 0.98 (%). By contrast, openness grade was lower than relative illuminance, and the regression coefficient between them was 0.62. The difference between sky factor and openness grade was due to the effect of the projection formula of the fisheye lens. In conclusion, sky factor was a better estimator of relative illuminance than openness grade. Furthermore, it was shown that it is important to state clearly the kind of fisheye lens used when measuring sky factor or openness grade.

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This paper considers the timing of timber harvesting under uncertainty. The decision of a forest manager who maximizes the expected utility is formalized using a form of the closed loop control model. The stochastic optimization problem derived is very similar to the deterministic single stand problem known as the classical Faustmann formula, but there is a notable difference. Whilst optimal rotation periods are certain in the deterministic world, they are random variables in stochastic circumstances. Stochastic optimal rotation periods are difficult to include in forest economic analyses. Fortunately, under some technical assumptions, we can find a non-stochastic variable named "barrier" which corresponds to the optimal cutting stock size in the deterministic world. This paper shows that the von Neumann-Morgenstern forest manager cuts his/her trees when the stochastic stumpage values reach a certain amount, that is the barrier. Comparative statics on the barrier were conducted to evaluate the effect of planting costs and the degree of the manager's risk aversion. The results show that the barrier rises as planting costs increase or as the Arrow-Pratt index of absolute risk aversion becomes smaller.

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This paper presents a comparison of the accuracies of four ground-survey methods; point sampling (PS), line sampling (LS), circular plot (CP), and concentric circular plot (CCP), when used to estimate the current values of number of stems, basal area and volume per hectare. The comparison was conducted to evaluate the utility of the four methods for continuous forest inventory (CFI) for forest management. Data were gathered on two occasions from a sugi (Cryptomeria japonica D. DON) stand in the Takakuma Experimental Forest, Kagoshima Prefecture, Japan. After entering the data of the entire study area in a file, the sample-trees of each ground-survey sampling methods were selected by a BASIC program. For PS and LS, basal area factor 4 was used. For LS, the line length was 10 m, and stems on both sides of the line were selected. For CP, the radius was 6 m, corresponding to 0.011 ha; for CCP, the radii were 5 and 10 m, corresponding to 0.008 and 0.031 ha respectively. The sampling intensity was 12 samples, and the systematic sampling process was applied 10 times for each method. The accuracy of each method varied according to the variable. On both occasions, CCP was slightly superior to the other three methods for the estimation of basal area and volume, and CP was slightly superior for estimating the number of stems. However, there were no marked differences in sampling error between the four methods. Therefore, the most appropriate method cannot be selected solely on the basis of sampling error.

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In this study we compare the accuracy with which four ground-survey techniques estimate change. The methods compared are; point sampling (PS), line sampling (LS), circular plot (CP), and concentric circular plot (CCP), which can all be used as permanent samples in a continuous forest inventory system. Data were collected on two occasions from a sugi (Cryptomeria japonica D. DON) stand in the Takakuma Experimental Forest, Kagoshima Prefecture, Japan. For the PS and LS methods a basal area factor of 4 was used. For the LS method, the line length was 10 m, and the stems on both sides of the line were selected. For the CP method, the radius was 6 m, corresponding to 0.011 ha; and for the CCP method, the radii were 5 and 10 m, corresponding to 0.008 and 0.031 ha respectively. Twelve samples were systematically sampled and the process repeated 10 times for each method. The CP method was the most accurate for estimating the change in the number of stems per hectare, but there were no significant differences between the four methods for estimating basal area or volume.

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Variations in successions following commercial (industrial) cutting of pine forests in the eastern Siberia were studied. The dimensional hierarchy of trees in the stands were determined by morphometric methods. Structure and biomass of aboveground vegetation were studied. The greatest aboveground biomass was found to be near 70 ton/ha (100% dry matter). This biomass accumulation rate is close to natural coniferous forest with about the same growing stock in Hokkaido, Japan. Maximum average annual biomass increment was found to be 1.9 ton/ha.

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