We analyzed the characteristics of 283 sites where sika deer caused bark-stripping damage in plantation forests in Kumamoto Prefecture, between 2000 and 2001. We developed four prediction models of the occurrence probability of bark-stripping damage using logistic regression. As independent variables, we used 16 factors, including topographic (elevation and slope angle), geographic (distance from the nearest road, etc.), vegetation (the number of cells used for forestry, agriculture, etc.), and stand (planted species and stand age) factors. The model with the lowest Akaike Information Criterion (AIC) and the greatest accuracy of classification showed that bark-stripping damage was strongly related to elevation, slope angle, and distance from the nearest road. The accuracy of the model was improved when the factors "planted species" and "stand age" were added. Finally, we drew a map showing the probability of bark-stripping damage. Such information should prove very useful in forest management planning.

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To examine the factors affecting the density of Japanese hare-the main prey of golden eagles-we investigated forest structure, understory plant biomass, and hare densities in the Akita-Komagatake mountain area. The densities of Japanese hare were estimated by fecal pellet counting. The hare densities correlated with the dry weight of the herbal plant biomass in summer (JulyAugust) ; however, it did not correlate with the estimated understory plant biomass above the maximum snow surface in winter (NovemberApril). In all seasons, the hare densities correlated with the forest canopy heights. These results suggest that understory plant biomass is the main factor affecting hare densities in summer. Canopy height is considered to be an effective environmental factor to estimate the hare densities because it controls understory plants, which form hare food and provides cover to hare for hiding from predators.

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A paired watershed experiment was conducted in the Fukuroyamasawa Experimental Watershed (35°12'N, 140°06'E) in University Forest in Chiba, The University of Tokyo. The watershed is located in a Tertiary formation area and is covered by a mixed plantation of Sugi (Cryptomeria japonica) and Hinoki (Chamaecyparis obtusa). The annual precipitation and annual mean air temperature are 2, 170 mm and 14.2°C, respectively. Watershed-A (WS-A, 0.802 ha) was the control watershed and Watershed-B (WS-B, 1.087 ha) was the treatment watershed. WS-B was clear-cut in the spring of 1999 and the same species were planted in 2000. The annual water yield in WS-B in the 3 years after cutting increased by an average of 295.9 mm/year. The discharge was often exhausted in the dry seasons before cutting, but after cutting the discharge was never exhausted. The discharge duration curve in WS-B stabilized after cutting because the ratios of ordinary, low, and scanty discharge to the total discharge increased.

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I proposed new measures for quantifying a stem form in relation to the stem surface area. The measures were given by the ratio of the stem surface area to the side area of a column, of which diameter and height were equal to stem diameter at a given height and total tree height, respectively. By this definition, the proposed measures were named "form-factors for stem surface area". These measures were computed using Japanese cedar (Cryptomeria japonica D. Don) and Japanese cypress (Chamaecyparis obtusa Endl.) data. For form-factors at 0.40.6, 0.8 and breast height, there was no significant correlation between these form-factors and stem sizes, i.e., total tree height and diameter at breast height. For form-factors at 0.5 and 0.6 in relative height and at breast height (κ_0.5, κ_0.6 and κ_b), there was no significant difference between cedar and cypress. The averages of κ_0.5, κ_0.6 and κ_b were respectively 0.903, 0.808, and 0.622 for cedar and 0.902, 0.799, and 0.612 for cypress. Therefore, it was concluded that κ_0.5, κ_0.6 and κ_b were most effective form-factors among the measures proposed in the present study.

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The CO₂ flux (RCWD) from coarse woody debris (CWD) was measured using an automated chamber system for two years from 2002 to 2003. RCWD showed clear diurnal changes that followed the daily change in surface temperature of CWD. In the short-term, RCWD decreased sharply with increasing water content during rain events and then increased slowly after rain events. In the long-term, RCWD increased exponentially with temperature and the RcvvE, in summer was about eight times greater than that in winter. The variation in RCWD at the same temperature was caused by variation in the water content owing to rain events. An exponential function using temperature and a quadratic function using water content explained 85% of the variance in RCWD and reproduced the long-term changes in RCWD caused by temperature and the short-term changes in Rc, , , caused by water content. RCWD showed diurnal, short-term, and seasonal changes with the temporal trends in temperature and water content.

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This study examines the influence of the growth state of Hinoki (Chamaecyparis obtusa (Sieb. et Zucc.) Endl.), estimated from its DBH and bark thickness; the body size of the Japanese Horntail (Urocerus japonicus (Smith)); and the presence of ovarian nematodes on the oviposition of the Japanese Horntail. When infected by ovarian nematodes, the potential fecundity of the Japanese Horntail decreased noticeably and the oviposition rate fell to almost half. There was no correlation between the growth state of Hinoki and the oviposition rate of the Japanese Horntail non-infected with nematodes. However, there was a negative correlation between the growth state of Hinoki and the oviposition rate of the Japanese Horntail infected with nematodes. The multiple regression analysis of the oviposition rate and number of oviposited eggs on the growth state of Hinoki, the body size of the Japanese Horntail, and the absence or presence of ovarian nematodes showed that the oviposition was affected by the absence or presence of ovarian nematodes and the body size of the Japanese Horntail. However, it was not affected by the growth state of Hinoki. Thus, the oviposition of the Japanese Horntail was not markedly depressed by the growth promotion of Hinoki.

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We constructed a diagnostic system of the interspecific hybrids between A. mangium and A. auriculiformis using DNA molecular markers. The species-specific RAPD (random amplified polymorphic DNA) fragments were selected in each species, and 42 SCAR markers were designed based on the sequence data of these fragments. Two codominant markers were detected in the SCAR markers. They are highly species-specific and show the phenotypes with different fragment length between the two species. These markers make it possible to reliably identify putative interspecific hybrids.

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Enrichment of microsatellite DNA regions was examined using triplex affinity capture (TAC) in the genomic DNA of Chamaecyparis obtusa. TAC reaction was operated under a condition of pH 5.2, and the sequences of 45 enriched DNA fragments were determined. The efficiency of TAC enrichment was evaluated based on the frequency and the length of CT/GA-repeats appearing in their sequences. The TAC condition was confirmed to be effective in enrichment, since 40 fragments (89%) possessed more than three-time-repeat arrays. More than ten-time-repeat array, however, was recognized only in 2 fragments (4%). By optimizing the TAC condition, this technique brings the possibility into a practical development of microsatellite markers.

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The root tips of Sciadopitys verticillata were observed lightmicroscopically to know their morphological type of arbuscular mycorrhizas. They had vesicules, intracellularly coiled arbuscules and hyphae spreading directly from cell to cell, which are the characteristics of Paris-type arbuscular mycorrhizas. The mycorrhizas of Cryptomeria japonica and Chamaecyparis obtusa were also observed, and their morphological types were Paris-type and Arum-type, respectively.

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High resolution molecular markers allow precise identification of clones and give information on diverse variables such as levels of pollen contamination, self-fertilization, and the genetic contributions of constituent clones as pollen donors. The use of such markers in seed orchard studies has accumulatively provided new insights, which could not be obtained by conventional methods, revealing that small percentages of mislabeling or misplanting occur in most seed orchards, and levels of self-fertilization are generally low (<5%), but often more than 30% of pollen comes from external sources. Furthermore, the genetic contribution of specific orchard clones as pollen donors often severely deviates from the genetic contribu-tion expected under panmixia. To obtain the maximum potential genetic gain, the following measures should be carefully applied: 1) to prevent errors in clone management, the identity of every ramet should be reconfirmed using molecular markers, and mislabeled clones should be removed, 2) to minimize pollen contamination, seed orchards should be established apart from conspecific forests, and the proportion of orchard pollen in the pollen cloud should be maximized by pollen management measures such as flowering promotion or supplemental mass pollination (SMP) treatments, 3) to reduce self-fertilization, the number of ramets of each clone should be reduced, 4) to promote panmictic mating, the male fecundity of orchard clones should be equalized, and extremely early-or late-flowering clones that do not match the flowering phenology of other clones should be removed.

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We identified problems in clarifying relationships between forest properties (e.g., broad-leaved/coniferous, canopy height, etc.) and evapotranspiration rates, and then proposed a plan to solve the problems. Furthermore, we showed how much the plan has accomplished. The problems were such that the generality of observation results is unclear. That is, it is unclear whether observation results at a site are applicable to other sites. We pointed out that developing a model that expresses evapotranspiration rates as functions of meteorological conditions and site parameters is useful for examining the generality of observation results. Then, we developed a model and described the model structure. For using the model, four examinations are required: 1) dry-canopy evaporation rates in a growing season, 2) wet-canopy evaporation rates in a growing season, 3) seasonal pattern of dry-canopy evaporation rates, and 4) seasonal pattern of wet-canopy evaporation rates. We have completed the examination of dry-canopy evaporation rates in a growing season using the Priestley-Taylor coefficient (α), and obtained the following two conclusions. First, α values for broad-leaved forests tend to be higher than those for coniferous forests. Second, α values for coniferous forests relate to canopy height.

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