In this research, the ski grounds developed on the mountain side slopes of the OHU mountains, running longitudinally through Iwate prefecture in Japan, were selected as the survey stands.
We compared those ski grounds with their nearly parallel neighboring natural forest belts to examine how those ski grounds affect the environmental conditions of earth such as surface erosion and somephysical properties of soil including permeability, hardness of soil, and coarse porosity. The results of the examinations are as outlined below. 1. Soil hardness The surface soil of the ski ground was apparently much harder than that of corresponding forest-belts. 2. Permeability: The forest land was apparently greater in saturated hydraulic conductivity and coarse porosity at spots on the slope different from the neighboring ski ground. On the other hand, the surface soil of the ski ground indicated the lowering of permeability in the order of nearly 10^-3. 3. Volume weight: The ski ground was apparently greater in volume weight at spots on the slope different from than the forest land. 4. Soil pH: A tendency toward a gradual increase in the pH of the soil was observed in the ski ground as a result of the line that is scattered over the ski ground after each ski season. 5. Erosion depth: An increase in erosion depth was observed on the surface of the ski ground, especially a marked increase in erosion depth in a ski ground which was most recently developed. 6. Infiltration: As a result of laboratory experiments examining the infiltration of soil in the ski ground using a simple lysimeter, we found that both the loss of litter and the hardening of ground surface considerably affect the infiltration rate of soil.

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Rooftop planting has thermal control effects on indoor environment. The effects, however, very greatly according to the building structure, residents' daily activities, and local meteorological conditions as well as with the planting structure. The present paper uses two approaches to discuss the thermal control effects of rooftop planting on the indoor environment of reinforced-concrete (RC) building.
First, we selected occupied RC building for a survey. From summer to winter, we measured the cross -sectional temperature and heat flow distribution from the roof to the occupied room. By reviewing the results of this survey, we clarified the thermal control effects of rooftop planting under conditions disctated by residents' daily activities, planting structure, and building structure.
Then we simulated numerically different room temperature conditions and sectional structures of roofs, including the soil layer thickness, water content, heat insulating material, and rooftop planting. Through this simulation, we calculated the long-term and daily changes of the room-side surface temperature of the ceiling. Using the simulation data as indices, we discuss the control effects of rooftop planting on the indor thermal environment.

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In order to improve the germination percentage ofLespedeza bicolorTURCZ. in revegetation technique, we conducted some indoor experiments with respect to the germination conditions and pretreatments for breaking hard seed. Light conditions did not affect the germination percentage of pretreated seeds, but incubation temperature influenced it as follows: Constantly high or low temperature was favorable for germination ofL. bicolor, whereas alternating temperature depressed it. As for the pretreatments for breaking hard seed, methods including scratching the seed coat were most effective. Hot-water immersion and forced-air drying were also successful. In an experiment wherein we divided the seeds into four seed coat color classes and soaked them in hot water for various lengths of time (t), germination percentage (Y) was well-described by a diminishing returns curve whose independent variable was t: Differences in the curves' shapes showed that the response to heat is affected by seed coat color. Accounting for the percentage of germination, seed viability, convenience and cost, it was considered that hot-water immersion at 70°C for 2-4 min. would be suitable as a pretreatment for increasing the germination percentage for practical propagation.

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