This study proposed the short-time period water-budget method, and estimated evapotranspiration in the Nutanotani watershed (34º27′N, 136º14′E), Mie University. The proposed method consisted of the following three analytical conditions: several critical discharges are selected between the 95 th and 365 th discharge in a discharge duration curve, each water budget period includes at least two continuous days of flood duration, and the water budget period is between 10 and 100 days. As for the calculated results by the proposed method, daily evapotranspiration were estimated throughout a water year. The difference between the maximum value and the minimum value of annual evapotranspiration in the same water year was 5.2% or less though the analytical condition of the proposed method was changed. The analytical condition of the proposed method can be adjusted according to the duration characteristics.

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The forest under common ownership in the former Toriumi district (now in Daito, City of Ichinoseki, Iwate Prefecture) provides a case study to clarify the relationship between municipal mergers and forests under common ownership in terms of management vision and issues for the future. First, the former and current state of this forest is reviewed, followed by information on developments accompanying municipal mergers in the area. The study consisted of interviews, a questionnaire survey, and document and literature searches. Results revealed that: (1) management of the forest was slack despite common ownership practices in the past. (2) Upon a forest of 186 ha belonged to the district formally with municipal mergers, relevant parties agreed to merge management and operation of the district’s forests. (3) The local population agreed to this move and was aware of the region’s responsibility for its own forests but had limited awareness of the need for relationships with other bodies. And they expect a forest function of public benefit. Focusing on the varied roles of forests and studying usage policies intended a tie-up with other bodies are crucial issues that are intended to effectively utilize local resources like forests under common ownership.

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We evaluated the relationships of some environmental factors to the success of Cryptomeria japonica afforestation and the degree of regeneration of hardwoods in C. japonica plantations in three watersheds in Akita Prefecture, a snowy region of northern Japan. Both stem density and canopy height of C. japonica declined as elevation increased: at elevations of more than ca. 650-m, heights fell below the threshold for the lowest site productivity class (least economical), and the densities were less than standard values. Various hardwoods such as Swida controversa, Eleutherococcus sciadophylloides, Clethra barbinervis, Prunus grayana, Fagus crenata, and Quercus crispula had regenerated in C. japonica plantations in all three of the surveyed watersheds. As elevation increases, it becomes harder to establish C. japonica plantations and easier for hardwoods to grow, but at much higher elevations, dwarf bamboos grow vigorously and inhibit the regeneration of hardwood trees. At elevations of more than 870-m, not only the establishment of C. japonica plantations but also the regeneration of hardwoods have been unsuccessful. We conclude that it is effective to give priority to areas at elevations of less than 650-m, which roughly corresponds to 2.0-m in maximum snow depth, for the efficient management of C. japonica plantations as commercial forests on a watershed scale. For plantations located in higher elevations, it is necessary to shift priority from commercial to environmental purposes.

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In a 21 years even-aged Japanese cypress plantation, we conducted investigation about the strip-cutting influences to the stand floor micro climates and vegetations for 15 months from cutting. The relative light intensity in the stand floor rose from 0.15 to about 0.3 in stand edge, and nearby 0.6 at the center of cutting area. Among the air temperature, air vapor pressure, soil temperature, and the soil water content in stand floor, soil temperature showed the most remarkable change at cutting area and stand edge. The diversity index (H´) of stand floor vegetation was calculated from the population of sapling and area coverage. Immediately after cutting, H´ of cutting area showed the minimum value. However, 15 months after, it was recovered even to the same grade as the stand interior. Through the investigation term, H´ of stand edge was still maintain high value, and in addition, H´ was rose in the stand interior. Strip-cutting has the feature in the broadly cutting area and edges, micro climate and the vegetation influences in the stand floor. These results were considered to be effective in the maintenance of the biodiversity on the Japanese cypress plantation.

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For evaluating the effect of coniferous plantation thinning on water resources, our previous study (Komatsu et al., 2007c) developed a model for predicting changes in annual evapotranspiration caused by coniferous plantation thinning. This model is comprised of transpiration and interception evaporation parts. The model needs to be verified from three viewpoints, stability of transpiration amounts with thinning, decrease in interception evaporation amounts with thinning, and applicability of the model to catchment scale. This study mainly focused on verification of the interception evaporation part. Based on seven datasets of interception evaporation derived from earlier publications, we compared model prediction results with the observed results. Model prediction results agreed fairly well with the observed results, indicating validity of the interception evaporation part of the model. Based on one dataset for verifying applicability of the model to catchment scale, model prediction results agreed fairly well with the observed results, implying applicability of the model to catchment scale. We should note that validity of the transpiration part of the model was not examined. Applicability of the model to catchment scale was not fully examined due to lack of observation data. Thus, we raised observation data that should be required for further model verification and presented guidelines for future observation studies.

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To estimate the downslope distance of leaf-litter transport in a given time on the forest floor, we conducted a field experiment with artificial leaves and used the data to construct two models for the transport rate of those leaves. A statistical model with three independent variables was derived from stepwise multiple regression analysis of the field experiment data : the component of wind speed at 1 m height that was perpendicular to the contour line, the forest floor vegetation cover, and slope gradient. An empirical model having the same variables was developed with additional consideration given to the process of leaf movement. The empirical model is regarded as more accurate than the statistical model, because it has a lower Akaike Information Criterion (AIC) value. To derive the transport rates of real leaves, we calculated the ratio of transport rate between the real and artificial leaves for nine species. These ratios ranged from 0 to 6.1. For leaves of deciduous species, the ratio tended to be higher the larger was the area and the lower was the falling velocity. The empirical model and the ratios of the transport rates promise to be useful for predicting leaf transport on a forest floor similar to our research site and for determining the size of the area that contributes leaf-litter to streams.

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An overabundance of Sika deer (Cervus nippon) at Mt. Ôdaigahara, in west-central Japan has necessitated the introduction of exclusion fences to protect forest decline from excessive feeding damage. However, the effect of these exclusion fences on the biodiversity of arthropods within the protected areas has not been investigated. In this study we examined the relationships between the volume of dwarf bamboo (Sasa nipponica), the major forage for the deer, on associated with browsing by deer and the structure of ground beetle assemblage. Both inside and outside of the exclusion fences, pitfall traps were setup in plots that had been assigned treatments of either no treatment (control) or artificial clipping of dwarf bamboo. Ground sticky traps were also set up in each plot to sample the abundance of small animals as the diet of ground beetles. Bamboo volume did not reltate to abundance, species richness, or diversity of the ground beetle assemblage. The abundance of the most dominant beetle species, Leptocarabus kumagaii, increased positively in response to both bamboo volume and the abundance of Orthopterans. The second most dominant species, Pterostichus fujitai, did not relate to bamboo volume, but decreased in abundance in relative to the propotions of open canopy. The third most species, Pterostichus microcephalus, decreased in abundance relative to bamboo volume, but increased positively in response to the abundance of Collembolans, Dipterans, and Hymenopterans. These results suggested that reduction of bamboo volume by browsing of deer did not affect the diversity of ground beetle aseemblage but affected its structure.

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To evaluate the mechanical stability of the Japanese larch (Larix kaempferi Carr) against wind loading, tree-pulling experiments were conducted in Tokachi, Hokkaido. The Japanese larch forests of this region are frequently subjected to strong winds from typhoons. These winds can cause root breakage and damage tree stems. Wind damage is a major source of economic loss in this region. The relationship between angle of inclination at the tree base and the turning moment showed that average angle of inclination was 9.7º at the maximum turning moment Mmax. Correlation analysis revealed that the correlation coefficient between M_max and the diameter at breast height D was greater than that between M_max and other elements (tree height (H), slenderness ratio (H/D), stem volume (D²H), weight of branches and leaves (W_cr), stem weight (W_s), total weight (W_t) ). Significant relationships were observed. D was the best index of M_max. M_max increased in proportion to the 2.6 th power of D for uprooting and to the 3rd power of D for stem breakage. It was suggested that the mode of failure varied with the diameter; larger trees were uprooted, while smaller tress were broken.

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The cost recovery from wildland recreation has become international issues. In Japan such trends are found only in specific facilities such as mountain toilets. However, diverse cost recovery methods had developed at Mt. Fuji in Edo period (1600∼1867), and contributed to the trail and climber management as well as to local economy just like current ecotourism guidelines. There exists no record on environmental education but environmental impacts were much smaller than current ecotourism. The author analyzed the trail and climber management, and its cost recovery methods based on historic documents and clarified the following. First, six mountain villagers not only managed four routes, but they visited Edo (Tokyo) and other areas to invite potential customers to Mt. Fuji as early as in the 16th century, and managed them properly. This contributed to sustainable development of local communities and brought Mt. Fuji boom in the early 19th century among the populace. Second, in the earlier stages climbers often complained of inconsistent amount of fees solicited at many places. Gradually the accommodation managers in each mountain village charged a lump-sum payment in advance, and the climbers received vouchers valid at respective gates. Furthermore, the unification of the climbing fees and discount to specific climbers was proposed. Third, gradually hospitality management rules was established to sustain climber-dependent communities. Four, Omiya Shrine in charge of the mountain top went backward to charge individual fees at the crater wall.

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This paper describes the characteristics of high resolution satellite data, methods to observe single trees and forest stands using it, and the results of previous studies. It also introduces its applications and discusses problems and future directions. High resolution satellite data can be used to observe individual trees, to identify treetops by local maximum filtering, and to segment individual tree crowns by the watershed method or the valley-following method. Since digital numbers of satellite data show different values even in a forest stand of the same species depending on the relationship between the position of the sun and the direction of the tree crown surface, object-oriented classification is recently used for extracting forest information. High resolution satellite data have been mainly used for urgent issues such as forest damages and in cases when it is difficult to obtain information in fields. Though the problems as optical sensor still remain, information, which are obtained from high resolution satellite data, certainly increase by the advance of sensor resolution. I consider that it is important to accumulate experiences on its analysis from a viewpoint of drawing such information practically and coping actual issues.

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