CO_2 emission and CH_4 uptake by forest soils were measured in two Hinoki cypress stands (TNG and FMY) in Higashitsuno Village, Kochi, southern Japan. In each stand, control and thinning plots (20×20 m^2) were established adjacent to each other in the spring of 2002. The gas flux was measured by the closed-chamber method every month from August 2002 to March 2003. The means for CO_2 emission rates in the control and thinning plots were 1.24 and 0.91 gC m^<-2>d^<-1> in TNG, and 1.39 and 1.44 gC m^<-2>d^<-1> in FMY. The means for CH_4 uptake rates in the control and thinning plots were 3.20 and 2.13 mgCm^<-2>d^<-1> in TNG, and 2.12 and 2.53 mgCm^<-2>d^<-1> in FMY. The analysis of the repeated measures ANOVA revealed that the thinning plot in TNG had lower CO_2 emission rates (P=0.03) and marginally lower CH_4 uptake rates (P=0.07). In the thinning plot of TNG, lower CH_4 uptake rates may be related to lower soil bulk density due to soil compaction and erosion. In contrast, the thinning in FMY did not significantly affect CO_2 emission, and the interaction of sampling time and plot was significant for CH_4 uptake (P=0.04). The results suggest that the effect of thinning on soil CO_2 emission and CH_4 uptake may differ among Hinoki stands.

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The effect of thinning on leaf-fall dynamics in a following year was studied in three Hinoki cypress stands (TA, TB and FM) in Higashitsuno Village, Kochi, southern Japan. In the spring of 2002, a pair of 20×20m^2 plots was established adjacent to each other in thinned and unthinned blocks in TA and FM, and heavily and lightly thinned blocks in TB. Leaf-fall of Hinoki cypress was measured every month from July 2002 to March 2003. Amount, time and duration of leaf-fall were compared among the plots by the logistic model. Total leaf-fall was decreased with thinning due to canopy foliage removal. The time of maximum leaf-fall rate differed by 12 days among the stands, but did not differ greatly between two plots within a stand (1-2 days). Duration of leaf-fall greatly differed among the stands, but did not differ between two plots within a stand. Although thinning decreased the amount of leaf-fall of the following year, it did not affect time and duration of leaf-fall strongly in Hinoki cypress plantations.

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The inherent regularity of branching and degree of plasticity in relation to light environment were comparatively investigated in two closely related shrub species Vaccinium hirtum and V. bracteatum. Vacciniumhirtum is a clonal and small shrub less than 2 m tall, while V. bracteatum is less clonal, and up to 5 m in height. About 50 aboveground stems were selected for each species at various light conditions. For both species, branching patterns were quantified by the number, length, and elevation angle of daughter shoots produced at the parent shoots. Effects of parent shoot length and light level on the branching patterns were also examined using multiple regression analysis. In both species, number and length of daughter shoots were positively correlated with parent shoot lengths, indicating size-related branching rules existed in Vaccinium hirtum and V. bracteatum. In V. bracteatum, there was a significant effect of light on the branching patterns, suggesting a high degree of plasticity in response to light conditions. These results suggest that parent shoots produced larger number of shorter and more vertical daughter shoots in V. bracteatum at higher light conditions. In contrast, branching patterns were strongly determined by the parent shoot length and less influenced by light conditions in V. hirtum, implying a strong internal regulation and low degree of plasticity in branching. These results suggest that long and erect parent shoots produced shorter and more horizontal daughter shoots in V. hirtum regardless of light conditions. These differences in the regularity of branching patterns and degree of plasticity can be relevant to the differences in growth habit between Vaccinium hirtum and V bracteatum.

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We observed the fruit foraging process of Angelica tree Aralia elata by frugivorous birds in a warm-temperate coniferous plantation in order to study the feature of seed dispersal of A. elata. Three bird species, those were Japanese white-eye Zosterops japonicus, Oriental turtle dove Streptopelia orientalis and Willow tit Parus montanus, were observed foraging fruits of A. elata among 14 frugivorous bird species observed in the plantation. S. orientalis was considered not to contribute seed dispersion because to be a seed predator. The most effective disperser of A. elata was concluded Z. japonicus with its high frequency of eating fruits. Few seeds were dispersed under the crown of the mother tree of A. elata by birds. It was estimated that seeds of A. elata eaten by birds were dispersed widely in the plantation.

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Edible mushrooms, Lentinula edodes, Pholiota nameko and Naematoloma sublateritiu, were inoculated to Quercus crispula killed by the infestation of Platypus quercivorus. All three mushrooms flushed fruitbodies not only from logs cut in 1m length, but also from standing dead trees. For all three mushrooms, more fruitbodies were harvested from logs cut from trunks higher than 2m above the ground than from logs cut from trunks lower than 2m above the ground, suggesting that the lower part of trunks with a large number of entry holes bored by P. quercivorus are not suitable for cultivation of these edible mushrooms. L. edodes were inoculated to the logs at different timing after felling. The amount of fruitbodies was larger from logs inoculated at 4 days after felling than from logs at 3 months after felling. Three strains of L. edodes with different capacities to prevent mycelial growth of the symbiotic fungus of P. quercivorus were inoculated to standing dead trees and logs. The amount of fruitbodies was the smallest when "TohokuS10" that has the highest preventive capacity was inoculated. These results suggest that Q. crispula trees killed by the infestation of P. quercivorus are useful for cultivation of edible mushrooms, but it is difficult to combine harvesting large amount of fruitbodies and controlling emergence of P. quercivorus.

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Reutilization of food waste is expected to establish a social system in which all kinds of waste are recycled. We investigated the utilization of fermented food waste as a substrate for a nutrient of sawdust cultivation of an edible mushroom, Pleurotus ostreatus. When Pleurotus ostreatus was cultured with a medium consisting of sawdust and rice bran (3:0.5 involume), the addition of the food waste to the medium at 6.4% of total volume gave similar cultivation time and fruit body yield to the standard medium (sawdust:rice bran=3:1). Pleurotus ostreatus was cultured with only sawdust, the addition of the food waste at 19% gave similar fruit body yield to the standard medium, but cultivation time was prolonged, as can be expected from the decreased growth rate of the mycelia. Harvested fruit bodies did not differ in shape and color from those obtained with the standard medium. The cultivation time was decreased by mixing perlite which would improve aeration in the medium. These results indicate that the food waste can be used for commercial cultivation of Pleurotus ostreatus.

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Forest fire occurrence danger rate was predicted using human factors which are the main factors responsible for the forest fire occurrence and meteorological elements which are causative factors. A target area in Hiroshima Prefecture was classified into 117 meshes of 10 km mesh units, and the forest fire occurrence danger rate for each mesh from 1998 to 2002 was taken as a target variable. The descriptive variables used were population density as a human factor, vegetation as a non-meteorological factor, and effective humidity, effective rainfall and MO (Experimental Live Moisture) as meteorological factors, and multiple linear regression analysis was performed. When the prediction accuracy by a multiple regression equation was assessed in terms of conformity with the number of fires which actually occurred, a multiple regression equation using population density, vegetation and effective humidity as a meteorological environmental factor was found to have the highest conformity.

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Water content of surface soil was investigated by comparing adjacent thinning and control plots in Hinoki cypress plantations (TNG and FMY) in Higashitsuno Village, Kochi Prefecture. Thinning was carried out in the spring of 2002. In TNG and FMY, the soil type and stand age were different. Water content of surface soil at 5 cm depth was measured by the oven-drying method (using 100mL soil sampler) every month from August 2002 to December 2003. In addition, water content was also measured automatically by the Time Domain Reflectometry probe (TDR) every hour. The average of volumetric water content measured by the oven-drying method in the control and thinning plot in TNG was 38.5% and 48.1%, respectively. In FMY, it was 32.7% and 42.0%, respectively. Two-way ANOVA revealed that the thinning plot has significantly higher water content in surface soil than the control plot in TNG and FMY (P<0.001). The frequency distribution of water content by TDR showed that the water content in the control plot tended to decrease dramatically in TNG and FMY. The water content of surface soil in the thinning plot increased because evapotranspiration decreased as result of reducing the number of trees following thinning. Although the soil type and stand age were different between the two plantations, the results suggest that the water content of surface soil in a Hinoki plantation increases following thinning.

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Floor vegetations of Sugi (Cryptmeria japonica) plantations made after terrace paddy-fields were studied. Sugi plantations after terrace paddy-fields (terrace plantations) showed high site quality accounting for high canopy height. Species richness (d=Species number/log_<10> (Plotarea)) of vascular plants on forest floor varied from 3.6 to 31.7, and it was explained by canopy openness and amount of A_0 layer. There were no significant differences between normal plantations and "terrace plantations" for species richness in each life form, in each seed dispersal type and in total. Common species in forest plantations in Kochi, Lindera sericea, Callicarpa mollis were inferior for frequency, coverage and plant height. Some indicator plants, which show high productivity of the site, were observed in "terrace plantations". For both of canopy height and indicator plants, high productivity of "terrace plantations" was confirmed.

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In order to investigate the damage due to outbreak of zonate leaf blight of Swida controversa, seasonal and within-crown distribution patterns of defoliation caused by this disease were studied in a cool temperate deciduous forest in the northeast part of Kyoto Prefecture, Japan. Proportion of shoots with blighted leaves increased from July to October in the first-order shoots elongating in May and in the second-order shoots elongating from June to July, and from August to October in the third-order shoots elongating from June to July. Defoliation was evident from July to August on the first-order shoots, and from August to September on the second and third-order shoots. From September to December, the number of leaves decreased due to the disease infection and naturally-occurring death. Defoliation was severer at the lower leaf layers than at the upper leaf layers of canopy trees, whereas defoliation was slight in suppressed trees irrespective of leaf layers.

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