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Outdoor experiences are important for infants to grow healthier.This report studies on the effects of Waldkindrgarten in Germany by researching two Waldkindergartens in Augsburg, Bavaria. Parents selected Waldkindergarten to let their children to grow healthier by experiencing nature and they recognized the educational effects were improvings of communication, hands skill, less stress, and so forth. On the other hand, they pointed the tasks were educational programs were different at each Waldkindergartens,lack of teachers, and so forth.

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1. PurposeThough canopy interception increases with rainfall intensity (Tsukamoto et al. 1988), few studies on this phenomenon have ever been carried out and its mechanism is unknown. In this study the author analyses the relationship between rainfall intensity and canopy interception based on the observation in a young Chamaecyparis obtusa stand and introduces a new hypothesis on the mechanism of this phenomenon.2. MethodCanopy interception was measured in a young Chamaecyparis obtusa stand, age 11-12, in the Hitachi Ohta Experimental Watershed of Forestry and Forest Products Research Institute (Ibaraki Prefecture, Japan) for the years of 1999-2000. Canopy interception was derived as the difference between gross precipitation and net precipitation (summation of throughfall and stemflow). Rain events were delimited when no rainfall was observed more than 6 hours since the cessation of rainfall. The author considered for those rainfall events that were more than or equal to 20 mm and analyzed on an hourly basis.3. ResultsIn each rain event canopy interception intensity (hourly canopy interception) was proportional to rainfall intensity (hourly rainfall). The inclinations of the regression lines for rainfall intensity and canopy interception intensity were calculated for all the rain events for two years of observation. These values of inclination are defined as the dependence of canopy interception intensity on rainfall intensity. The dependence of canopy interception intensity on rainfall intensity shows seasonal change: it tends to strong in summer and to weak in winter.4. DiscussionSince rainfall intensity is not included in the heat budget method as a parameter, dependence of canopy interception intensity on rainfall intensity cannot be explained by heat budget. Thus far, two canopy interception processes have been considered: evaporation of interception during rainfall and after rainfall. The author proposes the third hypothesis to explain above mentioned results. That is, a raindrop hits the canopy and it splashes to produce a lot of small droplets which can evaporate quickly. The stronger rainfall becomes, the larger the size of raindrops are (Marshall and Palmer 1948). This gives rise to kinetic energy of raindrop, therefore, the number of splashed droplets increases with rainfall intensity.In the Mito Meteorological Observatory (about 25 km apart from the observation site) relative humidity during rainfall at the same time with the observation site was 94 % with a standard deviation of 1.9. If you assume a constant relative humidity of 95 %, a calculation demonstrated that a small droplet with a radius of 25 micrometers that falls at the terminal velocity disappears after only 2-3 m fall by evaporation depending on air temperature. This hypothesis can explain the seasonal change in the dependence of canopy interception intensity on rainfall intensity. The reason why the dependence of canopy interception intensity on rainfall intensity is strong in summer is that water vapor pressure deficit is high in summer and the splashed droplets can evaporate with ease under high temperature.

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Rainfall and runoff were observed at bare land watershed (0.048ha), vegetation recovery watershed (0.12ha) and forested watershed (0.14ha) to study difference of the runoff characteristics with vegetation recovery in granite mountain. Observation was conducted at the university forest in Aichi. Peak discharge and runoff coefficient of bare land watershed was higher than those of forested watershed. Peak discharge and runoff coefficient of vegetation recovery watershed are between those of bare land watershed and forested watershed. The runoff peak and runoff coefficient characteristics are found to be changed with vegetation recovery, but more time is required for runoff response recovery than the surface vegetation change.

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Effects of soil physical properties on rainfall-runoff responses have already been evaluated through an analysis by the one-dimesnional Richards' equation. A new challenge for the scaling-up application of this method to two-dimensional slope was made in this paper. The theoretical analysis employed several dimesionless parameters derived from the slope topographic properties such as slope length and gradient as well as soil physical properties reprsented by a soil pore distribution function. The role of runoff processes on a two-dimesional slope in rainfall-runoff responses was successfully assessed by quantative distributions of rain-water to four componets consisting of unsaturated storage, groundwater storage, subsurface flow and saturation overland flow. An increase of the water storage on a slope responding to a rainwater supply, which contributes to a decrease of the peak runoff, was basically controlled by soil physical properties, indicating an agreement with that obtained from the one-dimesional vertical infiltration process. Our analysis for the two-dimensional runoff process on hillslope quantitatively evaluated that the increase of water storage may be coupled with an occurrence of the saturation overland flow.

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We investigated micro geomorphology, light environments and species composition of riparian vegetation along a montane stream in northern Japan. Vegetation structure was compared between sites around a dam and sites of more up stream.
In sites around the dam, micro geomorphology was relatively homogeneous and the light levels were higher than in sites of more up stream.
In sites around the dam, vegetation paches larger than in sites of more up stream. Species diversity in vegetation paches were not variance, however, species diversity of whole study sites were relatively homogeneous in sites around the dam than sites of more up stream.
In sites around the dam, Pioneer trees such as Alnus and Salix invaded.
In sites around the dam, earth and sand accumulated and river slopes became gentle and stable. These created relatively homogeneous micro geomorphology and large vegetation paches and promoting tree invation.
These changes of environments reflected relatively homogeneous species composition.

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Introduction
Riparian disturbance has recently considered to play important role in regeneration of diverse tree species of riparian forests. We investigated spatial distribution of vascular plants in a temperate riparian forest to elucidate the role of debris flows on the secondary succession and species diversity in a riparian forest.

Study site and methods
1) Study site
The study was conducted in Kanumazawa Riparian Research Forest (KRRF), northern Japan. The Kanumazawa forest has contrasting stands (riparian and an adjacent terrace). The riparian stand contains a mixture of various species, while the terrace is overwhelmingly occupied by Fagus crenata and Quercus crispula. Around KRRF, 315 vascular plant species has been recorded, 81% of which are found in the riparian zone.

2) Spatial distribution of vascular plants
Vegetation survey was performed in August 2000. Sample quadrats of 2x2m were regularly placed with 10-m spacing (totally 2.47ha, n=203 for the riparian stand and 112 for the terrace). All vascular plants in the understorey (<3m in height) in each quadrat was recorded.

3) Tree regeneration on debris avalanche and stable forest floor
Sapling (>30cm in height) census was performed in each of the 2x2m quadrat to compare densities of tree saplings between the riparian and terrace areas. The census has been continued every two years from 1994. On a debris avalanche (680m²) formed in 1988, both secondary succession and tree regeneration have been followed from 1992. We systematically placed 27 2x2m quadrats on the avalanche. In each quadrat we recorded species and the degree of vegetation recovery in August and monitored established seedlings in September. From 1996, we also monitored all saplings on the avalanche and in an adjacent canopy gap. Only canopy and subcanopy tree species were analysed.

Results
The riparian stand contained more species in understorey than the terrace. Species diversity was also significantly higher in the riparian zone than on the terrace.
Vegetation structure contrasted between the two stands. On riparian forest floor excluding debris avalanche, perennials, shrubs and ferns occupied a total of 78% of recorded species in each quadarat, and trees less than 10%. On the debris avalanche, the frequency of tree species accounted for 18%. In contrast, the terrace stand was occupied by trees (canopy or subcanopy) and shrubs by nearly 90%, and herbaceous and fern species was rarely found. Thus riparian vegetation consists mainly of various herbaceous and fern species, while those on the terrace of woody species.
Sapling density was generally low over the KFFR, but in sites with soil disturbance saplings were relatively abundant. Saplings of 26 species (80%) of canopy and subcanopy trees have established on the debris avalanche, though in the canopy gap, only Aesculus turbinata was regenerating. Dominant species on the avalanche were Acer mono, Fagus crenata, Ulmus laciniata, Cercidiphyllum japonicum, and Zelkova serrata. Survival rates of these saplings became lower with increasing years after the debris flow. These results suggest that debris flow provides suitable sites for tree regeneration but its effect on the seedling establishment appears to be short-lived.

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Dynamics of the undergrowing bamboo, Sasa kurilensis population was investigated for 8 years after mass flowering and death, with special reference to behavior of the unflowered patches. Sasa species often dominate in the undergrowth of the forests in the cool-temperate and boreal zones in Japan. Mass death of Sasa provides the chance for tree species to regenerate.
In 1995, S. kurilensis flowered to die over thousands ha near the Lake Towada, northern parts of Japan. We set a 1 ha permanent plot (Kougakudai Plot) to observe the dynamics of the beech forest after mass death of S. kurilensis in 1996. There were non-flowered S. kurilensis population among the flowered population. The total area of non-flowered patches was 0.41 ha within the 1-ha plot in 1996. However some of these population flowered several years after mass flowering. Twenty-one percent of the non-flowered population had been died till 2003.
Although Sasa species are reported to produce tens of thousands of seeds when they flowered simultaneously in the wide range, they produce few seeds in the small-scale flowering. In Kougakudai Plot, mean seedling density after mass flowering was 25.6 / m² in 1996. However we hardly observe the seedlings in the later flowered populations. Vegetation dynamics in such patches may be different from that in the mass flowered population, because other species can grow without the competition with Sasa seedlings in such patches.

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A background of various long-term hydrological phenomena in University Forest in Aichi, the University of Tokyo, is given by a dynamics of its forest ecosystem since the 1920s into the next several decades. Dominant species has changed from P. densiflora to Q. serrata and is predicted to be Q. glauca in the future.

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