Forests at the urban fringe are very important as a factor of the attractiveness of urban life, but the decrease of forested areas is inevitable due to the rising market value of forest land. This paper examines the decreasing forests of the urban fringe and proposes alternative plans for the preservation of these areas. Forest area per capita (FAC = F/N) is calculated from the following formula: (F/N) = a・exp(p(N/S))…(1), where F is forest area, N is population, S is city area, N/S is density per sq.km, and a and p are coefficients. In the example of 44 districts in Osaka prefecture in 1990, parameter a is estimated at 11,022 and p at -0.00429. The coefficient of determination (r^2) is 0.973. From the population and forest areas in Takatuki city in Osaka prefecture over 25 years, parameter a is 833.50, p is -0.000556 and r^2 is 0.973. The city of Takatuki expects that the population there will increase to 400,000 by the year 2000. If N is 400,000 and S remains constant in Eq.(1), the forested area in Takatuki decrease by 955 ha. by the year 2000. The degree of forest adequacy (DFA) is calculated from the following Mitscherlich function : DFA = 100(1-exp(a・(F/N))…(2), where a is the function parameter. In the example of green areas, populations, and DFA of residents at 6 elementary school districts in Takatuki city in 1985, a is -0.024 and r^2 is 0.845. DFA decreases as forest area per capita decrease. For example, the forest area in Takatuki, where the population is predicted to be 400,000 in the year 2000, should be increased by 556 ha. to keep the same DFA in Eq.(2).

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A new type of hypsometer, called a J-type hypsometer, which utilizes a distance meter was developed, and some of its characteristics was tested. The K-type hypsometer uses a distance meter as does the J-type hypsometer, however, the J-type facilitates measurement. Height measurement testing on a forest stand suggested that the J-type hypsometer was as precise as other hypsometers, but required greater measurement time. A separate test under optimal measurement conditions revealed that longer distances and lower height measurements caused lower precision, and that the J-type hypsometer did not require more measurement time than a blume-leiss hypsometer. It was concluded that the J-type hypsometer is useful in Japan because a great part of Japanese forests grows on mountainous slopes, areas in which this type of hypsometer facilitates height measurement.

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The purpose of this study is to determine the appropriate landscape image for Japanese cedar stands on the basis of three stand factors : the stand age, the level of pruning and cleanliness of the stand, and the amount of shrub layer. The forest landscapes were classified into 10 typical types, these types were then analized by applying semantic differential image analysis. The results of factor analysis clearly classified the landscapes into some groups based upon vitality, orderliness, and space perception. These three images correspond to the stand age, the level of pruning and cleanliness of the stand, and the amount of shrub layer and/or stand density, respectively.

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A diameter distribution growth and yield model for Caribbean pine and a linear programming (LP) harvest scheduling model were dynamically integrated so that they could be operated routinely through a mixture of macros and spreadsheets on a PC. The growth and yield model produces stock table estimates of log assortments via equations predicting net basal area/ha, maximum diameter at breast height outside bark, standard deviation of all diameters at breast height over bark and number of stems per hectare at any future age from inputs of basal area/ha, maximum diameter at breast height and side bark, standard deviation of diameters at breast height and stems/ha at a specified age, together with initial stocking and use of a Reverse Weibull probability density function. The LP model can be used to schedule harvests annually from numerous stands or blocks for up to seven years ahead subject to constraints on areas available, allowable logging methods, logging productivity, equipment and manpower productivity, market demands and storage capacities at ports or utilisation plants. The use of spreadsheets catered for sophisticated matrix generation and report-writing, while also providing a simple means of integrating the harvest scheduling model with outputs from the growth and yield model.

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