In order to clarify changes of runoff characteristics of pipeflow, measurements of precipitation and pipeflow were conducted at a forested watershed situated in the paleozoic-mesozoic hills for three years. Similar changes in runoff characteristics were observed for two pipes ; the maximum discharge rate of pipeflow increased, the recession hydrograph of pipeflow became steep, and the duration of pipeflow discharge became short. However, the changes of runoff characteristics had no significant effect on relationships between total rainfall and total discharge from pipes. Based on observations of sediment yield from soil pipes, it was suggested that the pipe structure changes caused the changes of runoff characteristics of pipeflow.

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Potted, two-year-old Pinus densiflora seedlings grown under outdoor condition were carried into the greenhouse, which had an adjusted minimal temperature of 18°C, on February 20th, March 2nd, 12th, and 22nd before budding. They were again returned to the outdoors on May 21st. Afterwards, we determined the percentages of lammas shoot formation, the lengths of winter buds at the end of December, and the numbers of male and female flowers in the next spring. As heating treatments in the greenhouse initiated earlier, the percentages of lammas shoots and the lengths of terminal buds became greater. The number of the male flowers in the heated seedlings became more abundant than that of outdoor seedlings, while the number of the female flowers became fewer. The elongation of the terminal buds as the result of the lammas shoot formation seemed to be related to the differentiation of the male flowers. However, the number of the male flowers was infrequent in excessively-elongated buds. Moreover, few seedlings had both male and female flowers in any treatment.

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The effects of temperature on the terminal bud formation of Populus×euramericana cv. 1-214 grown under short-day condition were investigated. When the night temperature was 25°C, the day temperature of 20 to 30°C exerted little influence on the critical photoperiod of the terminal bud formation, but the lower temperatures of 10 to 16°C were promotive under longer daylength, and the day temperature of 10°C induced the terminal bud formation even under 18-h photoperiods. Under the constant tempera-ture of 15°C, 14.25-h photoperiods showed SD effect, but under the lower and higher temperatures than 15°C, 14.25-h photoperiods showed LD effect.

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An investigation was performed on the nutrient levels of a 30-year-old Pinus massoniana (masson pine) plantation and the nutrients supplied to the soil by litterfall on the upper, middle and lower slopes in Fujian Province, China. The total biomass accumulation on the upper slope was 82 t ha^-1, and those on the middle slope and lower slope were 2.4 times and 2.9 times, respectively, as that of the upper slope. Because undergrowth of the masson pine plantation was rich, the biomass of the undergrowth was equivalent to 11-17% of the above ground of masson pine. The undergrowth plays an important role in nutrient circulation. Usually, after clear-cutting a masson pine plantation, the leftover organic matter on the ground is courteously burned. In this investigation, the total amounts of organic matter (sum of leaves and branches of masson pine and organic matter of the undergrowth and A₀ horizon) left on ground after clear-cutting were 21.5, 46.4, 59.8 t ha^-1 on the upper, middle, lower slopes, respectively, in which N contents were 187, 400, 460 kg ha^-1, respectively. Large amounts of nutrients will be washed away after clear-cutting and burning preparation. If clear-cutting is repeated in short rotations, it is a concern that Mg would not circulate smoothly in the ecosystem.

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An attempt was made to select a statistical model for a neural network were used for selection of trees for thinning. AIC, MDLP, and FPE were selected as models with higher generalization ability, and a three-layer back-propagation model was used as the learning algorithm. This was applied to a two-output pattern, whose output was "thinned" or "unthinned", as well as various input and hidden patterns, a number of learning data and some learning conditions. It was found that: (1) Many of the models showed good results when the number of hidden units was one or two degrees. (2) When the number of hidden units was one, the number of error patterns recognized in learning was zero, from the view point of generalization, and the results were the same as those when the number of hidden units was two. (3) Irrespective of whether the number of output units was one or two, good generalization was shown even if the learning data accounted for about 20% of all data.

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This paper aims to examine the structure of residents' consciousness on man-a gement of rural forest, focusing on the difference among inhabitant attribute types using chi-square test. Among residence term types, significant difference between new comers and established residents was found on knowledge of the communal forest and recognition of no use and management of the communal forest. Among occupation types, significant difference was found on recognition of use and management of the communal forest to conserve the rural landscape, recognition of use and management for prevention from disasters or for water conservation, and participation in maintenance of the communal forest in cooperation. It is assumed that these difference especially appeared between farmers and white-collar workers or people without regular occupation. Among types of farm management will, significant difference between the positive and the negative was found on knowledge of the communal forest and participation in maintenance of the communal forest in cooperation. In a conclusion, these attributes will are recognized as the most direct factor that effects upon management of rural forest.

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Changes in the density and distribution of Sika deer within a 520 ha catchment in Kyushu mountain range were estimated by dendrochronological method. Through previous studies and investigating the present relationships between density of faecal pellets and browsing rate, annual bark stripping rates were shown to be an indicator of past deer densities by employing dendrochronological techniques. Young(from 4 to 10 years old)Japanese cypress plantations were shown to have high carrying capacity through the relationship between year after planted and faecal pellet densities. Increases in the area of young plantation over the whole catchment during the period from 1982 to 1991coincided with a measured increase in rates of bark stripping. After 1992, the area of young plantation declined, but rates of bark stripping remained high. These results suggest that initial expansion of young forest plantations caused increases in the carrying capacity for deer and consequently increases in deer population size. It is suggested that increased densities of deer, caused increased pressure on available food resources, and consequently deer proceeded to disperse and throughout the whole catchment. Hence, the past and present densities and distribution of deer seems to have been greatly affected by the size and arrangement of young forest plantations.

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New self-locking, mechanically functional carriage was devised and developed, which is exclusively used for uphill yarding under cable logging system of a standing skyline and a main line, together with upper and lower stoppers. The carriage consists of a runner and two semicircular frames, which are connected with the runner by hinges and drawn by springs each other. The stoppers are movable on the skyline by release of its inside wedge, namely by pulling a rope from the ground. The principle of the self-locking depends on the relations of size among three cuttlefishly shaped parts of the choker-cone and two stopper projections. The feature of the apparatus exists in its simple structure, freedom from trouble, and realizing one effort of operation from lateral yarding to transport of logs including self-locking. The reliable function of the carriage was recognized through some field tests at the felling site and its practical use is near at hand.

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We present methods of reinforcing the aggregate base course confined by the cubic structure of geotextiles, in order to reduce the settlement of aggregate by improving the rigidity of aggregate base course. An aggregate base course using geotextiles has conventionally been reinforced by placing the geotextiles between the subgrade soil and aggregate layer. We compared the placing method with the cubic structure method experimentally. The settlement occurring at the center of the loaded portion of the aggregate surface confined by the cubic structure of geotextiIes is smaller than that of the conventional methods. Parameter u_t/u_s, expresses the bearing effect of the base course, specifically the rigidity of the aggregate layer. The result of the bearing effect of the base course is obtained in the case of combining the conventional method with the cubic structure method.

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