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Long Term and Large Scale Studies at the MONDORI-Dani 16ha Forest Plot in Ashu, Kyoto. Long term and Large scale research is difficult to continue for long term, because the members will easily change in short term and long term foundations is rare. University training forest can be suitable to carry out long term and large scale research. We want to summarize how could be carried out establishment and 3 times censuses of this study plot. Another purpose is how to continue this study with no official support from University forest which reduced their research because of right sizing. Research site: The MONDORI-Dani plot was established in Ashu research forest of FSERC, Kyoto Univ. in 1992, to investigate long term dynamics of cool temperate climax forest. Three times censuses have been done every 5 years, All trees of upper 10cm by DBH were measured with diameter. At the time the status of trees were checked and remarked. All area of the MONDORI-Dani catchment is covered by plot area, which totally is 16ha. Plot was divided to 256 sub quadrates, each size is 25m*25m. The dominant species were Cryptomeria japonica, Fagus crenata, Querqus crispula, Betula grossa.

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More than three decades has past since the launch of the first earth observing satellite, Landsat-1, in 1972. The accumulated images since then allow today retrospective monitoring of an ecosystem of a large area for a relatively long period. Observations of a large area for a long period are indispensable for an LTER. The change detection is an application of remote sensing, which can detect changes of forest canopies, or forest disturbances. With a time series of images, a history of the disturbances can be retrospectively extracted. Forest management today tries to mimic the natural disturbance regime so that the anthropological impacts would not exceed the tolerance of the ecosystem. In addition, anthropological disturbances have been observed to alter the succession and the biodiversity of stands afterward. Thus, the natural and anthropological disturbance regime is an indicator of the forest succession and the biodiversity that can be observed by the remotely sensed images. Remote sensing can be a good indicator that translates the results from intensive LTERs to a more straightforward manner so that the results can be extended to the all managed stands of the region. To prepare the images for the retrospective monitoring in future, we have to continue observation, archive them with metadata, and exchange information and ideas with people of different disciplines, as LTER participants always do for any other kinds of data.

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The area of desert and desertificated land in China is increasing by 14 thousand km2 every year. Major causes of desertification are excessive felling, grazing and agriculture, which are induced by human-activity. Greening is necessary to restore these deserted areas, and Chinese and Japanese government and NGO have achieved the artificial planting in the Loess Plateau of China so far. However, since the study about tree physiology was unsatisfactory, the "aged small trees" (poplars which repeat die-back) are often found in planting areas in the 1970s because of the lack of water. Therefore, it is very important to study about tree physiology and pick up the kinds of trees which are very drought-resistant for the purpose of selection for tree plantation. The measurement of stable-carbon isotope (d13C) is very useful to estimate the water-use efficiency of C3 plant, and the study of stable-carbon isotope have produced good results in the selection of the kinds of crop plant which are very drought-resistant. Thus, the objective of this study is to research drought-resistant character of trees along with gradient of precipitation in the Loess Plateau of China and to estimate the kinds of planting trees which are appropriate to each area. The correlation between ring width, stable carbon isotope and climate data are obtained using tree samples taken from the Loess Plateau of China. There was not good correlation between ring width and precipitation or temperature, and it is considered that the formation of tree rings are affected by factors other than climate condition. On the other hand, there is high correlation between stable carbon isotope of latewood and precipitation or temperature, and it is thought that the stomatal aperture is highly influenced by climate condition. Thus, it is suggested that it is useful to estimate drought-resistance of tree species on the basis of the relation between stable carbon isotope and climate data.

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Vertical and temporal trends in photosynthetic capacity (maximum rate of carboxylation (V_cmax) and maximum electron transport rate (J_max)) and leaf properties (LMA and leaf nitrogen per area (N_area)) in major three species, Betula platyphylla, Quercus mongolica and Kalopanax pictus were investigated. Generally V_cmax and J_max were lower in lower layer of their crown. Kalopanax pictus showed the highest V_cmax till August and the highest J_max till July among species. In three species, V_cmax was maximal in late June to late July but declined slowly with increase in leaf age. Vertical variability in V_cmax was described well by changes in N_area. However, top leaves of Q. mongolica showed lower V_cmax / N_area ratio despite of higher N_area compared with lower layer (August and October), suggesting that these top leaves were suffered from some stress, such as strong light or drought. On the other hand, the relation between V_cmax and N_area differed through season and among species. V_cmax / N_area ratio was maximal in late July but declined to October in three species. In late July, the apparent fraction of leaf nitrogen to Rubisco (R_F) as well as LMA reached the highest values. From these results, temporal variation in V_cmax was affected by the change in allocation of leaf nitrogen to Rubisco with leaf age. In conclusion, it was suggested that when the regression equation of V_cmax versus N_area was used for this deciduous forest, it was necessary to take account of the effects of the change in leaf age of each species.

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Photosynthetic rate(A), transpiration rate(E), stomatal conductance(gs), leaf water potential(Yw), and leaf water relations were studied for canopy leaves of Quecus mongolica(Qm), Betula platyphylla(Bp), and Kalopanax pictus(Kp). gs and A reached maximum in the morning and continued to decrease until dawn. Yw decreased below -1.5MPa during midday but leaves maintained enough positive turgor via osmotic adjustment. Yw did not affect A and gs. From these results, we concluded that hydraulic limitation did not cause any severe stresses in these canopy leaves.

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Somatic Embryogenesis and plant regeneration from immature seeds of Pinus armandii var. amamiana, a species threatened with extinctionEmilio Maruyama, Yoshihisa Hosoi, and Katsuaki Ishii (Forestry and Forest Products Research Institute)Pinus armandii var. amamiana (Yakutanegoyou) is a five-needle pine species endemic to Japan. The natural population of Yakutanegoyou is restricted to the Tanegashima and Yaku Islands (Kagoshima Prefecture). Because, it is believed that the natural population is only 1,500 to 2,000 individuals, this species has been registered as endangered species in the Red Data Book of Japan Wildlife¹⁾. In situ and ex situ conservation of this species has being considered as a prior importance. So, we try to reproduce this species by tissue culture techniques through somatic embryogenesis as an alternative of ex situ conservation.Somatic embryogenesis in Pinus armandii var. amamiana was initiated from immature seeds collected from early July. Collected seeds were washed with 100% ethanol before disinfection in 2.5% (w/v available chlorine) sodium hypochlorite solution for 30 min. Then, seeds were rinsed with sterile distilled water. After seed coats had been removed, the megagametophytes that containing immature zygotic embryos were cultured on EM^1-2) medium containing 2,4-dichlorophenoxyacetic acid and 6-benzylaminopurine. Embryogenic cells were transferred to fresh medium and subcultured at three-week intervals in the same medium. After proliferation, embryogenic cells were transferred to EM media containing maltose and abscisic acid (ABA), and supplemented with and without polyethylene glycol (PEG) and activated charcoal. After two months of culture, the best result regarding to the number of somatic embryos per Petri dish was obtained on medium containing maltose, ABA, PEG, and activated charcoal. Cotyledonary somatic embryos were transferred to EM medium without plant growth regulators. About 50% germination frequency was achieved. Germinated embryos that showed epicotyl growth were transferred into vessels containing vermiculite or fluorialite substrate fertilized with modified Nagao's plant food solution^1-2) and kept in culture room before ex vitro acclimatization.1) Environment Agency of Japan (2000)Threatened wildlife of Japan -Red Data Book 2nd ed.-, Japan Wildlife Research Center2) Maruyama, E. et al. (2000) Plant Biotech. 17: 281-2963) Maruyama, E. et al. (2002) J. For. Res. 7:23-34

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This study examined contribution of phototropism in development of tree form on forest slopes, where spatial gradient in light environment exists. Main stem inclination (MSI) of mature trees on forest slopes were measured for Cryptomeria japonica (Cj), Pinus densiflora (Pd), Quercus myrsinaefolia (Qm), and Quercus serrata (Qs). MSI was larger in Qs, intermediate in Pd and Qm, and smaller in Cj. Intensity of phototropism and gravitropism in main stem of seedlings were determined on the four species. Change in MSI caused by phototropic response to unilateral illumination was larger in Qs, intermediate in Qm, and smaller in Pd and Cj. Change in MSI caused by gravitropic erection to artificial inclination was larger in Pd, intermediate in Cj, and smaller in Qm and Qs. Gravitropic erection to artificial inclination was inhibited by unilateral illumination. Intensity of the inhibition corresponded with the intensity of phototropism in each species. The intensity of phototropism in the seedlings and the MSI in the mature trees on the forest slopes were significantly correlated among those species, while the intensity of gravitropism did not showed significant correlation with the latter. Resultant stem inclination on forest slopes depends more on intensity of phototropism responding to spatial gradient of light environment than on that of gravitropic erection responding to passive inclination cased by such as slope falure.

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Policy measures for the restriction and the promotion of the forest management limited to specific areas in the private land by the government were examined. In a new policy based on the new Forest and Forestry Basic Law, one of its features are to limit the range of the object area of the subsidy based on the expected effectiveness of the forestry promotion. The stock of the resource is in excess compared with the demand. The ratio of the subsidy has increased extremely compared with the cost. Those are the background of the policy change to limit the object district of the forestry promotion.

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