The spatial distribution and topographic dependence of vegetation types and treepopulations were studied by using census data of 7, 940 trees ?? 5 cm DBH in a 6.875 ha plot located in natural forests in the Chichibu Mountains, Central Japan. The vegetation in the plot was divided into four types in terms of tree species composition and the 55 tree species were divided into four species groups based on the maximum total basal area of each vegetation type. The spatial distribution of each tree species population depends on the topographic gradient. Moreover, each vegetation type was differentiated according to the elevation gradient and the range of each vegetation type was affected by the degree of topographic development. Gradual change of vegetation types mainly composed of three species with stable tree populations, Tsuga sieboldii, Fagus crenata, and Fagus japonica, is explained by lack of large scale disturbance, occurrence of erosion and deposition in the whole area, and differing moisture regime along topography.

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A surface failure occurred after completion of the handy dynamic cone penetration test at 169 points in a 0.46 ha area, which was designed to clarify the ground characteristics related to the preceding collapse. The slip layer of these collapses coincided with the layer with a N_c value of less than 1 accompanied by a slight increase to the deeper layer. We named the layer located deeper than 50 cm, a "fragile layer". Out of 169 points surveyed 54 points had a fragile layer. All of them were located downward of the knick line, and 50% of their bottom boundary was 7080 cm deep. Meanwhile, 15 old scars 77 ± 6 cm in depth had no fragile layer, and were also traced only downward of the knick line. Comparison between the depth of the old scars and that of the bottom boundary of the fragile layer remaining on the slope suggested that the fragile layer plays an important role in the generation of these collapses. Shear strength of the fragile layer was 0.5 kN/m², but it abruptly changed to 10.0 kN/m² in deeper layers. These fragile layers may be missed if we use the conventional penetration test criteria, i.e., N_c-value of about 510 accompanied by a significant rise in the adjacent lower layer, but should be a key to detecting a surface failure in the future.

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We conducted a carbon balance analysis on the timber production process from plantation to lumber production based on a sugi (Cryptomeria japonica) forest stand just before harvesting. The production process was divided into three phases: the tending phase, the log-production phase, and the lumbering phase. The study area was set up in a sugi (Cryptomeria japonica) forest stand owned by Hoshino Village, Fukuoka Prefecture in Japan. Our analysis showed that the amount of carbon sequestered in this forest stand just before harvesting was estimated at 201.53 Ct/ha, resulting in 100.92 Ct/ha in a log-scale. This amount was further reduced to 65.16 Ct/ha in the lumbering products. We also estimated the carbon-equivalent amount released by consuming energy for production under logging and sawing activities. Based on the total amount sequestered in this forest stand, the percentage of the carbon-equivalent release in the tending phase was estimated at 0.13%, while it was 0.39% in the log-production and 3.85% in the lumbering phase. Harvesting and sawing residues were estimated at 67.66% of the total amount in the forest stand. If these were utilized as biomass energy sources, their carbon-equivalent amount would become 19.33% without considering energy consumption for utility, and 18.08% with it.

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The delay of thinning in planted forests has become one of the major problems for Japanese forest management. Using the proportional hazard model, this study aimed at the estimation of the probability distribution of elapsed time to first thinning after Sugi planted stands become subject to subsidized thinning, and of the effect of real stumpage price to the distribution. The data of thinning history in the period of 1980 to 1999 was gathered for 250 ha of privately owned Sugi stands in Misaki, Kaminaka Town, Tokushima Prefecture, planted betwen 1964 and 1989. Two findings were obtained. Firstly, the probability that thinning occurs dropped after a peak at 7 to 8 years of elapsed time, resulting in a significant ratio of stands remaining without thinning. Secondly, the decision of first thinning was affected by the real stumpage price, defined as the ratio of stumpage price to forestry labor wage. The drop of real stumpage price was thought to be a cause of a sharp decline in vigorousness of thinning during the 20 years of the observation period.

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There are few studies dealing with the time series data for soil respiration and its spatial variationin a small mountainous catchment which is located on the complex terrain in Japan, generally. Soil respiration rate was measured at 96 soil colors in the small mountainous catchment (1.6 ha) in this study. The relation between soil temperature, soil moisture content ratio and measured soil respiration rate was expressed by one function in spite of the fact that the measured places were located in different topographical parts. To verify this function, soil respiration rate was measured at anothor 264 soil colors in the same catchment. The relative difference between calculated and measured soil respiration rate was 25%. The time series data for daily soil respiration was estimated by this function used with the monitoring data for soil temperature and soil moisture content ratio at 5 places in this catchment. These daily soil respiration rates fluctuated at almost the same time and their relative variation ranges between 50 and 140% in one year.

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Streamwater quality was measured for two years in a small, forested snow-covered basin in an inland part of Tohoku, Japan. The average major ion concentrations in the Himekami Experimental Basin were lower than nationwide averages. A change in streamwater quality mainly arose from the change in water discharge caused by rain or snowmelt. Positive correlations were found between discharge and pH, electrical conductivity (EC), and the Na⁺, Mg²⁺, Ca²⁺, Cl^-, HCO^3-and SiO² concentrations, and negative correlations were found between discharge and the SO₄^2- and NO₃^-concentrations. In the early stage of snowmelt, we observed a clear effect of snow coverage on the water quality, and the Na⁺, Cl^-, SO₄^2-, and NO₃^-concentration increased with snowmelt, owing to the high concentra-tions in snow. After the active stage of snowmelt, the Na⁺, Cl_-, and SiO₂ concentrations were affected by a dilution effect of the water from melting snow. By contrast, the SO₄^2- and NO₃^- concentrations also increased after the active stage of snowmelt. Increases of both ion concentrations are attributed to either outflow out of the snowpack or their elution from shallow soils. However, the response of the two ions during an event that involved both rain and melt water suggests that SO₄^2- and NO₃^- in streamwater during snowmelt were strongly affected by outflow out of the snowoack and their elution from shallow soils, resoectivelv.

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DNA moleculermarkers were developed for discriminating Zao larch, which remainsin the Zao mountains, from Japanese larch, which is widely distributed over the mountain regions of central Japan. RAPD fragments appeared specifically in Zao larch or in Japanese larch were screened respectively, and SCAR primer-pairs were designed. Consequently, three markers appeared highly specifically in Japanese larch, and two markers in Zao larch, were acquired. Using these five markers simultaneously, it became possible to discriminate Zao larch and Japanese larch wth a misidentification probability of 4.91 × 10^-7. Of these five markers, three markers with higher discriminatory power, easily identified thetwo kind of larches (probability of misidentification: 2.45 × 10^-5).

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Serious damage caused by glaze occurred in the forest of Hidaka from the 22nd to the 23rd of February 2004. The entire damage area has reached about 163 ha where 84% of the area is occupied by Japanese larch (Larix leptolepis Gordon) forest. In this research, the weather conditions at the time damage occurred were investigated, and the relationship between the damage rate to Japanese larch forest and site conditions was analyzed by using various analysis methods. It was considered that a warmer air (air temperature above 0°C) layer must have existed at the upper air (more than 400 m in altitude) during the nights of 22nd and the 23rd. This is why the glaze did not damage the higher altitude area. The scores of aspects were higher in the N-NW direction, which suggests that the damage might have been expanded by the winds after ice accretion. The scores of the average diameter at breast height indicated that the damage rate in larger diameter (>25 cm) threes was reduced.

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Forest certification has widely accepted as integral tool for addressing SFM issues around the world. The primary purpose of this study is to discuss key issues of two types of dominant certification schemes-FSC and PEFC through a comparison of current statistics and status of program implementation. On the other hand, the important of another parallel approach which can be illustrated by the initiatives of the forestry sectors and governmental agencies being previously opposing segments of a broad range of stakeholders is discussed. The development of the FHPC is a result of consensus building based on societal values of what were acceptable forest harvesting practices to maintain ecosystem integrity and long-term socio-economic needs. The formula and implementations of these codes are far from perfect, but have significantly contributed to advancing forest harvesting practices. Two types of approaches-forest certification and practice codes, will play an important role as a "catalyst" and "powerful driver" towards responsible forest harvesting practices because these initiatives have requirements related to corporate environmental policies, industrial process planning, use of best availabletechnology, self-auditing, and a commitment to continual improvement.

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Portable field spectroradiometers with high spectral resolution developed in the last decade have made it possible to trace photosynthesis processes at multi-scale by measuring changes in certain narrow band reflectance that is associated with the photoprotective mechanisms. Optical sensors mounted in airborne vehicles have spectral resolution as high as that of portable field spectroradiometers. This provides a possibility to estimate the global carbon budget using remote sensing techniques. Photoprotective mechanisms including xanthophyll cycle-dependent thermal energy dissipation and water-water cycle-dependent active oxygen scavenging are briefly reviewed. Three reflectance indices, namely, normalized difference vegetation index (NDVI), water band index (WBI) and photochemical reflectance index (PRI) are introduced and their ecophysiological meanings are explained. In addition, the application of these indices in estimation of photosynthetic carbon gain from the single leaf to the landscape level is discussed.

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