The forest stratification and species diversity of the old-growth Cryptomeria japonica D. DON natural forests on Yakushima were studied. Five fine-scale permanent plots of 0.80-1.00ha were established in these forests, and the height and DBH of all living trees were measured twice with intervals of 15-19 years. Using the discriminant analysis method, each plot was stratified into two strata and the degree of stratification was quantified. The upper and lower strata were almost entirely composed of coniferous and broad-leaved species, respectively. The difference in the intensity of past cutting was considered to have affected the species diversity. The recruitment, mortality and stratification patterns showed that the regeneration of coniferous species might depend on the occurrence of large canopy gaps due to typhoons. The stability of the maximum tree height suggested that the typhoons limited the maximum tree height. A negative correlation between the degree of stratification and species diversity was observed, indicating that the degree of stratification was indirectly affected by the effect of past cutting on species diversity. From these results, it was concluded that both artificial disturbance due to cutting and natural disturbance due to typhoons played an important role in the dynamics of forest stratification and species diversity of C. japonica natural forests on Yakushima.

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The current situation and problems of forest management in Hungary need to be viewed in the light of the ecological and historical background of forestry in Hungary. As far as the natural environment is concerned, the following ecological factors have been the most significant in the development of forest management. Hungary is a small Central-European, lowland country, surrounded by mountain ranges on all sides. A continental climate, small amounts of annual precipitation, relatively low levels of air humidity, hot summers, cold winters and the lack of densely forested mountainous terrain, tailor the potentialities of forestry management in Hungary. Furthermore, forest resources are limited - forest cover is only 18% of the total land area, of which 85% is deciduous stands, and 70% of that is hardwood stands. To add to this, the forest is threatened by game overpopulation, frequent droughts, heavy and wet snowfalls and decreasing ground-water levels. As for the history of forest usage, more or less uncontrolled utilization of forest resources characterized the period until the second half of the nineteenth century, when the first Forestry Law was enacted in 1879. After the First World War, the Paris Peace Treaty (Versailles 1920) deprived Hungary of 84% of her forest cover. The Second World War's high demand for wood once again led to large-scale exploitation. As a consequence, Hungary's forests became more or less even-aged and less diverse in species. During the communist era, vast barren areas were afforested by non-native conifers, hybrid poplars and black locust. Though these plantations proved useful in protecting agricultural areas from deflation and erosion, their harvest and regeneration will place a heavy burden on their owners and managers, as huge areas are maturing at the same time. Furthermore, these plantations have recently turned out to be susceptible to climatic hazards, pests and diseases. A relatively short rotation and regeneration period, and the spatial and temporal concentration of logging operations were the main features of the 55 years of state forest ownership and management. From the middle of the 1980's, the importance of sustainable, environmentally sound, "nature-friendly" forest management has been emphasized. The recent privatization of forestland led to the development of private forest management, and the re-evaluation of forest management and forestry policy has become necessary to address the issues of the new situation.

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The recent transformation of the structure of forest ownership in Hungary, generated by the social and economic changes of the early 1990's, presented a brand-new operational environment for forest management. The main problems raised by the privatization of forestland are briefly as follows: 1. The number of forest owners and forest managers has become very high, laying a heavy burden on forestry authority and forestry policy. 2. The average size of the management units in the private sector has become very small, making yield regulation and sustainable forest management difficult. 3. Not only did the management units become smaller, but also, in many cases, forest areas belonging to the same owner are separated from each other. Forest management on these areas is inefficient and costly. 4. The majority of new owners, though the descendants of the original owners who managed the forests before the Second World War, lack experience and skills in forest-related activities, and therefore the assistance of forestry professionals is necessary, which increases costs. 5. A considerable proportion of forest owners are unwilling to co-operate with each other. 6. The number of absentee owners is high. 7. In state-owned forests, the marginal, degraded and poor quality stands were often (not always) privatized. 8. The forest stands' natural and structural endowments in the private sector are less advantageous for forestry than in state forests. 9. Finally, the nearly insurmountable task of management planning and supervision of private forests presses heavily on the shoulders of one single organization-namely, the State Forestry Service. In order to deal with the problems enumerated above, some measures have already been taken. Some of them were manifested as legal regulations under the framework of the Forestry Law (1996) and its enacting clause (1997). One example is the wide range of government subsidies, which are to support private forest management (especially joint management) and ecological interests in forestry. Others were carried out at the level of forest management policy, in accordance with the regulations of the new law. These involved changes in the areas of registration and supervision of private owners, the structure of management planning policy and the National Forestry Database. As might be expected, the adjustment of Hungarian forestry policy to the new working environment is a gradual progress. There is still a long way to go before we know whether the changes at the legal and professional level will prove appropriate or not. As a future consideration, the importance of communication and cooperation with the forest owners and the local populace, public participation in planning and decision-making, and the improvement of public relations policy must be emphasized.

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Recent policy measures have recognized people's participation in forest/watershed conservation in the Asian countries. In places like Nepal, where societies are highly stratified by caste/ethnicity, people's concerns and socioeconomic conditions have significant implications for implementation of watershed management activities. This paper analyzes the relationship between people's concerns, socioeconomic conditions, land use, terrain slope and proportion of caste/ethnic households. The analysis revealed that there is a significant effect of caste/ethnicity on people's concerns and socioeconomic conditions. It was also found that people's concerns are more serious in the medium and high slope areas compared to the flat areas. Predictor variables for food availability are proportion of low caste households in the ward, and medium and high slope area. For fuelwood availability, they are walking distance to fuelwood forest, ownership of farmland, low caste households, high caste households and proportion of level terrace in the ward. Proportion of low caste households is the main predictor of illiteracy, followed by high slope area. Thus, it was found that people's concerns are collectively affected by the socioeconomic conditions of the local people, land use and natural conditions.

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In this study, we applied a supervised classification technique for mapping the vegetation types in a tropical forest area. In applying the supervised classification technique, one of the problems is the selection of the training area. We used two methods of selection. In the first method the training area was selected directly from field observation. In the second method, we selected the training area from a paper printout of LANDSAT TM 542 using visual interpretation. The training areas from the two methods were then used for classifying the same image by the maximum likelihood classification technique. The maximum likelihood classification from the training area obtained by field observation gave a kappa accuracy of 90.7%. By comparison, the training area obtained by visual interpretation gave a kappa accuracy of 85.8%. The T test indicated that there was no significant difference in their kappa values, and through the overlay technique, the classification map obtained by both methods also showed similar consistency. Thus, the second method was considered to be an accurate and simple method applicable for tropical forests that are usually situated in remote areas with poor accessibility.

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