The purpose of this study is to evaluate the thermal environment in forest for human behavior. We set three stations. Two are in the experimental plots controlled to classify the stand density in a Larix leptolepis and Pinus densiflora mixed stand plantation. The other one is in the grassland as the contrast station. At these station, we observed air temperature, humidity, global solar radiation, wind velocity, Oxford index, Sol air temperature and Windchill index in one weeks at four seasons. We made a comparative study of the thermal environment in the forest and the grassland. Analysis of the provided following results: (1) In summer, the hot environment in forest were eased by the descent of air temperature, global solar radiation and Sol air temperature. (2) In winter, the cold environment in forest were eased by the ascend of air temperature and the descent of wind velocity, Windchill index. Accordingly we found the forest envieonment were more comfortable than the glassland environment. (3) In summer, Oxford index of the forest were higher a little than the glassland, and it means discomfortable environment. We made a comparative study of the thermal environment in the high density plots and the low density plot. Analysis of the provided following results: (4) In the high density plot, the hot environment were eased by the descent of Sol air temperature, and the cold environment were eased by the descent of Windchill index. (5) The humidity had a relationship to the stand density. It suggested a possibility of the descent of Oxford index by the deduction of the stand dencity. (6) The global solar radiation had a relationship to the stand density. It suggested a possibility of the quantitative control of bright in the forest. Accordingly we found Sol air temperature and Windchill index were usefull for the evaluation of the forest environment for human behavior.

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The cylinder method was used in situ to estimate net mineralization in surface soil (0-10cm depth) of an established (83-year-old) stand and young (2-year-old) stand of sugi (Cryptomeria japonica) and hinoki (Chamaecyparis obutusa). The upper and middle part of the established stand and the upper part of the young stand consisted of hinoki and the lower part of the established stand and middle and lower part of the young stand consisted of sugi. Measurement sites were in the upper, middle, and lower sections in both stands. The amounts of inorganic nitrogen (NO_3-N+NH_4-N) found in the soil (0-10cm depth) were 1-10kg・ha^<-1> during one year, and no obvious differences between the sugi and hinoki stands or among the plots. The ratio of NH_4-N to inorganic nitrogen were decreaed from the upper to lower slope position in both the established and young stands. When the average soil temperature for one month became higher than above 5℃, net nitrigen mineralization occured and was accelerated with an increase of soil temperature. Net nitrogen mineralization increased from the upper to lower slope position in both the established and young stands. The ratio of NH_4-N to net nitrogen mineralization was higher in the established stand than in young stand. The ratio increased from the lower to upper slope position in the established stand, but there was no differece among the plots in the young stand. The net nitrogen mineralization in surface soil (0-10cm depth) in the established stand was 45-55kg ha^<-1>・yr.^<-1> and in the young standa was 50-80kg ha^<-1>・yr.^<-1>.

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Chamaecyparis obtusa ENDL. is one of the most important tree species for under-planting of multi-storied forests in Japan. Specific leaf area (SLA), photosynthetic capacity, light-photosynthesis curve, and chlorophyll content were measured on current year leaves of young C. obtusa trees growing under different light conditions in a multi-storied (Pinus densiflora S. and Z. -C. obtusa) forest. Photosynthetic rates were measured using the gas-phase oxygen electrode method. The results were as follows: 1) SLA increased remarkably under 40-50% level surface relative light intensity (LSRLI). 2) Photosynthetic capacity decreased under 40-50% LSRLI. 3) Saturation point of light-photosynthesis curve, and light compensation point decreased under low LSRLI, although initial gradient of light-photosynthesis curve is almost constant under various LSRLI. 4) Chlorophyll a・b ratio increased according to LSRLI, whereas, total chlorophyll content per unit leaf area is almost constant under various LSRLI. 5) The decrease in photosynthetic capacity under 40-50% LSRLI was due to the decrease of photosynthetic capacity per chlorophyll weight under 40-50% LSRLI. Based on these results, it is clear that the morphological and physiological characteristics of the current year leaves of C. obtusa showed remarkable changes under 40-50% LSRLI.

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Disturbance by various types of earth surface movement are characterized from a viewpoint of vegetation recovery to clarify their roles in forest dynamics. The earth surface movement refers to erosional processes and mass movement such as debris flow, landslide etc., which provide heterogeneous habitats consisting of several scoured (or denudation) and deposited zones. These scoured (or denudation) and deposited zones are the principal components of the earth surface movement to explain vegetation patterns and species diversity of forests. The disturbance intensity by earth surface movement can be graded from the forest floor less intensive to the conopy layer intensive. The effects of earth suface movement on modification of forest structure or promotion of regeneration habitats vary according to its intensity. We compared the disturbance by the earth surface movement with the other types of disturbance and generalized their roles in forest dynamics, by evaluating their effects based on the following three aspects: 1) physical intensity of destruction, 2) environmental changes for tree growth and recovery, and 3) modification of the succeeding disturbance regime. Variations in the effects of forest disturbance are one of the predominant factors controlling structural diversity such as species richness. Therefore, the wide ranges in size, intensity and degree of forest disturbance by the earth surface movement significaantly contribute to increase structural diversity. Further studies on spatio-temporal distribution of earth surface movement are needed to interpret long-term effects on dynamics and stability of forests.

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The effect of windbreak on wind erosion control was studied by model experiment in a wind tunnel. Three types of windbreak (Simple forest, Shrubs, Complex forest) and eight kinds of complex forest type windbreak were experimented as the models. Shrubs roughened the roughness of surface layer and enlarged the drag coefficient of tree trunk layer. Consequently the wind speed at the windward fringe was reduced and the recovery of wind speed in the windbreak was controlled, furthermore wind speed reduced much exponentially in the windbreak. As a result, it clarified that the complex forest type windbreak was a highly effective windbreak rather than simple forest and shrub type windbreak. Type4 windbreak showed the best effect on the reduction of wind speed to the point of 5H at leeward side, although the wind speed showed a tendency of quick recovery at the back of windbreak in this type. Type1 windbreak seemed to be beteer as a windbreak because of the uniformity of accumulation of drifting sand although Type8 windbreak was the best from the point of catchable effect of drifting sand. We conclude through the experiment that Type1 windbreak arranged trees and shrubs on alternate rows could be selected as the most desirable windbreak for erosion control in the desert area.

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Population of indigenous ectomycorrhizal (EM) fungi in degraded and eroded lands is generally low. Application of ectomycorrhizal fungi to their soils may be often effective. This paper examines the potential for management of EM symbiosis. Selection and screening of effective EM fungi are very important for inoculation and infection to pioneer plants. Candidate fungi collected at volcano Mt. Bandai in Fukushima and the Sakurajima Island in Kagoshima, and at poor granite site of Mt. Tanakami in Shiga were as follows: Pisolithus tinctorius (Pers.) Coker et Couch f. tinctorius, P. tinctorius (Pers.) Coker et Couch f. turgidus (Fr.) Pilat., P. tinctorius (Pers.) Coker et Couch f. pisocarpius (Fr.) Pilat., Astraeus hygrometricus (Pers.) Morg., Laccaria amethystea (Bull.) Murr. Particularly, Pisolithus group was the most common candidate and thay were associated with Pinus densiflora, Pinus Thunbergii, Betula Ermanii, Betula Maximowicziana, Alnus firma. Elementary species Pisolithus tinctorius were made up differeent forms at each site. Basidiospore inocula of Pisolithus and Astraeus, and vegetative inocula of Pisolithus were effective for two and three-year-old and especially current seedlings in Mt. Tanakami, in University Forest of Ehime University in Matsuyama, Ehime and the Sakurajima Is., Introducion of EM fungi to each site brought about good results for enhanced survival rate and increased seedling growth compared with each control, and their results were further promoted by using covering materials made of non-woven polyestel fiber.

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Rainfall, snow, throughfall and stemflow of Picea jezoensis, Tsuga diversifolia, Abies veitchii, Betula ermanii were collected at subalpine coniferous forest on Mt. Ontake, Nagano Pref., from June 1990 to May 1994. The pH of the througfall and stemflow were lower, and the EC of them were greater than the values of rainfall at the opening. The pH of rainfalls decreased according to increasing of EC, especially at the stemflow of P. jazoensis and T. diversifolia. The pH of throughfall and the stemflow of B. ermanii and A. veitchii related with the pH of rainfall at the opening. Although the pH of the stemflow of T. diversifolia and P. jezoensis kept even values irrespective of the values of rainfall at the opening. Ionic concentration of throughfall and stemflow were greater than the one of rainfall at the opening and snow. The ionic concentration in the rainfall was much less than the average data reported by Environment Agency becaouse of sample collection at high elevation. However, total ionic depositions were estimated as same as the average amount in Japan because of greater annual precipitation.

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Recently, we are studying on the relation between the vegetation and its environment in an arid area in northwest of China. In this paper, we reported some results on the measurement of air temperature and relative humidity which were collected in August and September from different areas of Xinjiang Uygur Autonomous Region and Gansu Province in China. Values of moisture per dry air were read out as another humidity indicator by the psychrometric chart based on the relationship between temperature and relative humidity. In comparison, the diurnal ranges of temperature in the desert of Xiaotang, especially near the ground, are larger than those in the oasis of Aksu. Moisture in the oasis is generally slightly higher than in the desert. It is thought that conditions in areas without vegetation show more clear diurnal variation of air temperature than those in oasis. Differences on temperature and humidity were not apparent from areas with sparse stand of Populus to areas with sparse Tamarix scrub on a river side, and as the remaining Populus stands became fragmentary and sparse in the deseart areas. In some cases, however, values of temperature were almost lower, and values of air moisture were higher in Populus stands than outside the stands. The tendency than desert areas were more hot and dry than oases was clear based on the measurements done intermittently for one day trip from Aksu to Korla. As big cities produce "heat-island", oases produce "moist-island" in the arid region because they include wide and well-cultivated areas.

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