Byram's fireline intensity values were calculated in order to estimate the intensities of Japanese forest fires by simulating a test fire using Rothermel's firespread model, which has been widely employed in analyses of North American forested ecosystems. The sensitivity of the fireline intensity approximation was determined by examining the variation in each of the fuel parameters. The results showed that none of the parameters, with the exception of surface-area-to-volume ratio, had a significant effect on fireline intensity. Therefore, constant valuesof these parameters could be used in the calculation, regardless of the type of fuel. The estimated fireline intensities were higher for fern grasslands than for forests, and were influenced by both the wind velocity and the slope. The fireline intensity values for most Japanese forests were calculated as below 850 kW m^-1 and were similar to those reported for North American forested ecosystems. However, fireline intensities in Pinus densiflora forests with dense Dicranopteris linearis undergrowth reached values of more than 20, 000 kW m^-1; similar values have been reported for Mediterranean-type ecosystems, such as fynbos and chaparral, which are widely considered to be adapted to recurrent fires.

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To evaluate the influence of geomorphic site conditions, such as microrelief and soil hardness, on the growth response of trees planted as a buffer forest around cultivated land (wheat farm), we measured the height growth of planted Picea glehnii, soil bulk density, penetration resistance profile, and relative elevation of the land surface. Tree height varied from place to place, and the ratio of dead trees ranged from 3040%. The soil bulk density averaged 1.24 Mg m^-3. The penetration resistance profiles indicated that a hard soil layer resulting from vehicular traffic occurred at depths of 0.20.6 m. The relationships between the three-year height growth of trees and three independent variables (relative elevation, soil bulk density and soil water content) were analyzed using stepwise multiple regression analysis. All the relationships were significant, and a lower relative elevation and higher local soil moisture and hardness resulted in a decrease in three-year height growth. We concluded that exceeding the optimum soil moisture in relation to microrelief and a hard soil layer have negative effects on the growth response of P. glehnii.

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We analyzed the relationship between the location of anchor points for H-type cable systems and the terrain factors related to slope failure potential. Slope failure potential is one indicator of the suitability of a terrain for a forest road network that connects effective anchor points. To determine such effective anchor points for H-type cable systems on a digital terrain map, we used a pair of skylines representative of those that have been rigged up for H-type cable systems in recent years. The height of the loading blocks was based on a temporary operation method that roughly ensures safety of the skylines by limiting tension of the lifting lines, the practicability of which we confirmed in this paper. Results of the analysis showed that slope failure potentials at the selected anchor points were significantly lower than at other points. At the selected anchor points, significant terrain factors that decrease slope failure potential were as follows: cross-section of slopes, turning point of inclination, catchment area, and their interactions. However, slope inclination at the selected anchor points was significantly larger than at the other points (a large slope inclination increases slope failure potential).

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To clarify the effect of cutting and regeneration on microbial activity, natural forest and selective cutting forest were compared to Gmelina arborea Roxb. plantations, shrubs, and arang-arang (Imperata cylindrica) in terms of microbial biomass Carbon (C), Nitrogen (N) concentration, C mineralization, Net N mineralization, Gross N mineralization, and N immobilization. Difference among natural forest, selective cutting forests, plantation, shrubs and arang-arang obviously changed microbial activities rather than amount of soil organic matter. The microbial biomass decreased about 50% in plantations and shrubs. The ratio of N immobilization to gross N mineralization in natural forest and selective cutting forest was low about 5070%, although it was high (more than 90%) in plantations and shrubs. The N supply was low in plantations and shrubs and much lower in arang-arang area.

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To evaluate the relationship between soil moisture excess and needle size, we studied Picea glehnii planted at a moist field and sampled needles that expanded in 2001, 2002, 2003, and 2004. We observed wide variation in needle length (L_t) among individuals: the lower the individual position, the shorter the needle length in 2001, 2003, and 2004. Although we did not observe a significant relationship in 2002, the deviation in L_t among individuals was the smallest for the four years. The mean L_t among individuals was small in 2002 and 2003, while it was large in 2001 and 2004. In addition, we observed yearly variation in L_t within individuals, but there was little change in the rank of its size across years. Furthermore, the mean L_t among individuals was positively correlated with evapotranspiration ability (λE') in the period that is considered to influence leaf expansion strongly. A large L_t was observed in the years with a large λE' and vice versa. These results suggest that both microrelief and weather conditions may affect soil moisture excess at the study site, and may cause variation in L_t among individuals and yearly variation in L_t within individuals.

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The validity of the regionalization of the Kanto Breeding Region was investigated from genotype by environment interaction (GEI) and genetic gain (ΔG) using the data of 21 clonal tests with 12 common elite clones. The degree of GEI in the Kanto Breeding Region was significantly large. As for the present four breeding area regime, the degree of interaction of clones by regions was larger than that of clone by progeny tests within a region, and both appropriate and inappropriate breeding areas existed together in terms of both GEI and ΔG. In order to consider the newly regionalization based on environmental conditions, principal component analysis (PCA) using climatic data was performed. Based on the result of PCA, the Kanto Breeding Region was divided into the inland side and the Pacific Ocean side, and one of this regionalization pattern for considering the data of clonal tests seemed to be more appropriate than the present four-breeding-area regime from the view of both GEI and ΔG. On the other hand, the integration of the present four breeding areas into two combined areas seemed to be unsuitable from the view of both GEI and ΔG.

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The present study investigated the evalua-tions of 17 Japanese forests that were made by 4 certification bodies based on the number and types of items that theyconsidered to be "requiring improvement." Materials were taken from the summaries of the evaluations that each body made publicly available on its web site. In all, the FSC uses 10 Principles and 56 Criteria to make evaluations.Of these, Principle 6 (Environmental impacts) and Principle 7 (Management plan) were cited by all certification bodies as "requiring improvement, " while there were differences in other items. At any rate, all 17 forests received certification, regardless of the number of items "requiring improvement". It was concluded that a common trait of the certification bodies was their educational or instructional evaluations.

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Flight ability of Hirticlytus comosus (Matsushita), one of the most serious insect pests of Podocarpus macrophyllus (Thumb.) in Japan, was assessed under laboratory conditions. Flight duration was measured by the tethered flight method and flight speed was measured by the fixed-distance flight test. The mean duration of a flight was 77 s, but the duration of a flight was 30 s or shorter for 14 out of the examined 28 adults. Some adults which flew for 180 s or longer were so exhausted that they could not walk after ceasing the flight. Mean flight speed was 1.58 m/s. Both flight duration and flight speed did not changed with the adult age. Mean and maximum distance of a flight were calculated from the estimated flight speed and duration as 122 and 1, 170 m, respectively. These results suggest that the flight activity of adult H. comosus is relatively low and thus the adults would make repeated short flights for dispersion and reproduction in the field.

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Genome sequencing efforts have been initiated recently for many plants and plantpathogenic microbes. These efforts are providing a new and powerful means of investigating plant pathogens. Here we briefly review the current status and futureprospects of genomics in plant pathogenic microbes, including bacteria, fungi and nematodes. We also describe our EST (Expressed Sequence Tag) project on the pine wood nematode, Bursaphelenchus xylophilus.

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The purpose of this paper is to understand the current situation of local dwellers in protected areas, by revealing the reality of biodiversity conservation management in those areas, and to examine the tangled relationships between nature and human-kind. In order to protect precious biodiversity on earth, discussions on this topic are carried out internationally, and protected areas are increasing throughout the world. Because local dwellers often occupy the areas which are also designated as protected areas, the rights of those people should be ensured. While preservationists and government authorities have achieved biodiversity conservation and succeeded in acquir-ing foreign currency by establishing protected areas and eco-tourism in them, those did not contribute to the economic benefits of local dwellers, but rather, jeopardized their customary lifestyles. These different attitudes towards nature by different stakeholders are causing conflicts between biodiversity and culture. It is indispensable to delegate some responsibilities for the management of protected areas from the central to the local, and to construct the management system which can share benefits among stakeholders, by providing direct meeting between self-supported local organizations and governments in conjunction with third parties such as NGOs.

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