|Budget Amount *help
¥2,000,000 (Direct Cost : ¥2,000,000)
Fiscal Year 1995 : ¥400,000 (Direct Cost : ¥400,000)
Fiscal Year 1994 : ¥1,600,000 (Direct Cost : ¥1,600,000)
The photosynthetic rate and the transpiration rate of Pasania edulis trees were measured under verious soil water conditions by controling watering in summer and fall in 1994, and those of Cinnamomum camphora, Pasania edulis and Quercus glauca trees were measured in the same way in 1995. And, the growth of Cinnamomum camphora trees planted in Hourai Sea-side Park in Marugame-city.
(1) The soil water conditions and the growth of the trees
The photosynthetic rate Pasania edulis trees showed the mid-day depression in summer even if the soil hold enough water. The reason of this mid-day depression was seemed high temperature. When the leaf temperature was over 35ﾟC,the photosynthetic rate became decrease. On the other hand, the transpiration rate increased by the leaf temperture. It found a close co-relationship between soil water potential and leaf water potential, and according to the soil drought, the photosynthetic rate and the transpiration rate decreased. The WUE (water use efficiency) showed lower in summer than in fall.
The photosynthetic rate and the transpiration rate of the Cinnamomun camphora trees and the Pasania edulis trees also decreased according to the leaf water potential, but the inflence of high temperature in summer on these two species were less than on pasania edulis trees.
(2) The growth of Cinnamomun camphor trees in Horai Sea-side Park
The soil comditions and root development of the Cinnamomun camphora trees planted in Horai Sea-side Park were investigated in spring in 1994. This park was on the reclaimed land, and the trees were planted about 20 years ago. However, the soil was compacted very densely. So, the root systems of the trees were very poor.
The soil improvement was dune in spring in 1994, and the investigations of the soil condition and the root development were carried out in winter in 1995. As the results, it was clear the effects of the soil improvement on the root development.