Diel carbohydrate dynamics were studied on a canopy-layer species of Hydnocarpus ilicifulius in Dry Evergreen Forest (DEF) in Thailand. The measurement was conducted in the beginning of dry season in 1997. Leaves, twigs, stems and roots were sampled every 3 hours during a 24-hours period, and contents of sucrose, hexose and starch in all tissues were quantified. The fluctuations of total nonstructural carbohydrate (TNC) content in every organ seemed to have a baseline with a few peaks on the line. The minimum values of TNC contents in all organs were around 1.00 mg gt of DW and they suggested a “baseline” of the fluctuation. The baseline would define a long-term carbohydrate storage in the organ and the peak showed the temporary increment. The peaks occurred at 3 to t hours later from the peak of organs immediately above. The different peak occurrences seemed to reflect the mass carbohydrate movement because the time difference in the peaks reasonably fit with the reported value of translocation rate. The ranges of diel fluctuations were equivalent to that of the seasonal change reported in the past. It was suggested that studies of carbohydrate contents in plants should take this large variation into consideration.

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To analyze carbon dynamics between leaves and the other plant parts, we developed a compartment model and compared the differences between canopy-layer species and underlayer species in Dry Evergreen Forest (DEF) in Thailand. Hydnocarpus ilicifolius was selected as a canopy species and Glycosmis parva as an underlayer species. Using our model, the carbon export rate was estimated by subtracting the changes in carbohydrate content from carbon gain by photosynthesis during a continuous 24-hour period. The results for H. ilicifulius suggested that assimilated carbon was stored as starch in the morning, but as monosaccharide for the rest of the daytime. Carbon export occuned not only in the night, but also during the day when the light intensity was low for H. ilicifulius. In the case of G. parva, the translocation occurred the most of the 24-hour period, with the highest carbon export during periods of sunflecks. Thus, translocation of carbon appeared to occur during night and under Iow light intensity in both species. Furthermore, the accumulated carbohydrate might change the form against the environmental changes. Our study showed that carbon flow in tree species could be more flexible than has generally been thought and that the dynamics differed between H. ilicifulius and G. parva.

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Research on the environmental knowledge and the utilization of plants by Tanimbar-Kei societies has been carried out. Data and information were collected from Tanimbar-Kei island in December 1991 and January 1992. The method used was by interviewing head of village, head of tradition (Orang Kaya) and persons who knew well about the useful plants and the environment.
The utilization of plant resources observed in the Tanimbar-Kei island was recorded, and there were more than 297 species consisted of 80 cultivated species, seven semi domesticated species and 2|0 wild species. Those species provide material used for : medicine, foods, material culture, construction, fence, firewood, rope, handicrafts, poison, tools, and others.
In the traditional life of Tanimbar-Kei society, the available natural resources reflected on various established customs and tradition. In the above relationship, a clear division was realized when research was conducted among the conserved, cultivated, and uncultivated areas. This relayonship was not merely dividing spaces where they live in, but followed by various rules on time of hunting and shifting in cultivation.
The structural units recognized by the Tanimbar-Kei were as followed : awarat (plants), rahan (house), rahan ruhun yalin (house garden), oho (village), ve’e (garden/dry field), kat (secondary forest), yat (primary forest), vavelek (place sacred), roa (sea), nangan (land) and naho (island).

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In Thep Prathan village, Eastern Thailand, there is an increasing interesting in wana kaset, a category of agroforestry. Wana kaset is a mixed plantation of useful trees, considered to be an imitation of natural forest by the farmers, however, is ofrather artificial characters actually. The purpose ofwana kaset is both for sale and for house consumption. Most species in wana kaset are edible trees, eaten as desserts or sweets. Farmers’ intention can be said to be the reconstruction of the forest by more sophisticated way, which supplies cash income, foods as a little luxury, and other good living environment also.

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