This paper presents a review of the spatial pattern analysis of individual trees in natural forest stands by the quadrat and distance methods. These methods have been used for three purposes (1) to identify spatial pattern, (i.e. uniform, random, or aggregated), (2) to estimate density and (3) to analyze spatial pattern structure. The separate use for each of the above purposes causes bias in density estimation. The concept of "intensity and grain" developed by PIELOU (1977) was applied to overview spatial pattern analysis. The intensity expressed by an index of aggregation has three roles; (1) for identifying spatial pattern, (2) for correcting bias in density estimation and (3) for analyzing grain of spatial pattern, i.e. mosaics, or sizes of clumps etc. Spatial pattern analysis methods from the point of the three roles are reviewed and spatial patterns of individual trees in natural forests and the problems in natural forest inventories discussed.

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This paper reports on the economic evaluation of simulated harvests resulting from various forest management plans. First, a series of procedures for the economic evaluation of forest management on the basis of sustainable forest plans were developed. The plans evaluated consist of a long-term plan, in which approximately equal areas would be cut during each working period, and medium-term plan, in which approximately equal amounts of labour would be involved each year. Costs, gross income, and net income of forest management are evaluated according to these plans. Next, Compartments 25 to 28 in the Tokyo University Forest in Chiba Prefecture were used as study areas, and they were assumed to be a working unit. The forest plans were made by using a geographic information system for sugi (Cryptomeria japonica) and hinoki (Chamaecyparis obtusa) plantations with 60-, 70- and 80-year rotations. Costs, gross income and net income for the plans were evaluated under nine sets of conditions of cost and timber price. Under the present conditions, net incomes per hectare were 1,176 thousand yen for the 60- and 70-year rotations and 852 thousand yen for the 80-year rotation. The investment in the study site was profitable even under the worst set of conditions, even though the internal rate of return for a coniferous plantation is low. Therefore, if Japanese foresters have sufficient growing stock and forest roads, they can derive high profits from forest management.

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Searching for an optimal harvest scheduling regime has been a major concern of forest managers. The balance of costs and benefits of a management practice vary depending upon its efficiency. This study addresses the harvest scheduling problem with a log transportation network within the integer programming framework. A harvest scheduling system was constructed with using commercial software, CPLEX, as an optimizer to search for an optimal tactical solution. A case study was conducted using a forest management problem in Chile over a short time horizon to investigate the effect of integer restrictions on road construction and harvest decision variables on the regime. Computational comparison of a linear programming formulation and integer programming formulation showed that without considering road construction constraints in the problem formulation, serious costs may result in the management regime. Timing of the harvest of a unit may also change when integer restrictions are imposed on the harvest decision variables.

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In this paper, a prototype of a public participation handbook is presented. This proposal can become a reference for producing official handbooks of the national forests in Japan. Procedures for public participation in the planning process are divided into following seven stages. (1) Pre-planning (2) publicity of the planning system and public participation process, (3) explanation of the present states and problems of forests, (4) collection of opinions, discussion and analysis, (5) preparation of assessments and alternative plans, (6) determination, explanation and recording of the final plan, (7) promotion of acceptance of the final plan. Under the present planning system in the national forests, an acceptable handbook is required, because public participation in the forest planning process is an essential factor.

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The profitability of forest management has been declining due to stagnating domestic timber prices and increasing management cost. With a waning in enthusiasm on the part of the forest owners, forest management is now in a state which is less than desirable. With this, there is no supply system which corresponds to the maturing of forest resources. In the river basin forest management system, it is necessary to constitute a system encompassing production, processing and distribution, from upstream to downstream. For this, it is vital that comprehensive information related to forests and forestry be systemized and a networked information system in a management unit be established. Such a network should provide the following functions 1) information exchange 2) collection of information for marketing 3) inter-connection with various industries 4) efficient management. In this paper, a sample system is proposed for the study site and related problems are discussed.

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Based on the system volume equation presented previously, a new index was proposed for analyzing the change of stem taper within a stand in competitive situations. Using this index, the stem taper variations was analyzed over time within a stand for Cryptomeria japonica and Chamaecyparis obtsusa. In both species, the stem taper was highly correlated with the diameter at breast height. The change in stem taper variations over time was examined in this paper and was found to be different between species.

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Since 1972, an experimental management system for Japanese oak (Quercus mongolica var. grosseserrata) has been studied in a natural Japanese oak forest approximately 200 ha in area in the Kyushu University Forest in Hokkaido. The management system was imposed by clearcutting in tongue-shaped blocks surrounded by shelterbelts; rotations were 150 years. The silvicultural process to which the natural oak forest has been subjected was designed to produce high-quality timber. For the 20 years between 1973 and 1992, the number of first-year oak seedlings established by the silvicultural process averaged 61,000 per ha per year. For the 20 years between 1972 and 1991, the area managed averaged 8.64 ha per year. For the 20-year period, the timber volume derived from thinning and final cutting averaged 240 m^3 per year. The average revenue obtained by selling this timber was 1,169,000 yen per year. The average cost of silvicultural management was 600,000 yen per year, excluding the management costs for staff members and related factors on the Kyushu University Forest. Thus, the average net revenue per year was 569,000 yen for the 20-year period.

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The author has developed "The Reserved Forests Database", which contains maps, photographs and attributive information for the retrieval of forest data. From this database, one can retrieve various types of information about reserved forests, including maps and photographs. The computer system of this database is based on the Macintosh personal computer. The hardware devices required by this system are a CPU, a monitor and an optical-disk driver, and the application software programs required are FilemakerPro and Grand-muse. Although graphic data requires large memory capacity, 300 data sets were successfully stored on one optical disk by using a data compression technique. This database can be applied to various purposes and can be used for the visual interpretation of a forest.

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