Chemical properties of tropical peat soils and soil solutions under sago palm plantation in Sarawak, Malaysia were discussed. Strong acidic soil reactions and high contents of organic matter were observed in most of soil samples. Chemical properties were obviously different between deep peat soils (DPS) and a shallow peat soil (SPS). Chemical properties in DPS changed with depth. Electric conductivity, ash contents and total nitrogen contents tended to decrease with increasing soil depth, whereas humification degree of peat soils tended to increase with increasing soil depth. Bulk density of surface layer was about 0.1 Mg m^-3 except for SPS and shrinkage of peat soil causing land subsidence have not occurred by land reclamation for sago plantation.
 Dissolved organic carbon, electric conductivity and acidity in soil solutions decreased with increasing soil depth. There was a significant positive relationship between dissolved organic carbon and acidity. Principal components of acidity might originate from various organic acids. Proportions of cations in soil solutions to those in soils were different due to their positive valences. Higher proportions of monovalent cations were in soil solutions compared to divalent cations. Fe content in soil solution was very low and high proportion of Fe was organic bound form.
 Physico-chemical properties of soils and soil solutions clearly represented the process of peat accumulation and soil formation condition. There was not clear relationship in deep peat soils between sago growth and chemical properties in soils and soil solutions.

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 A filed survey was made in the northern and central islands of Vanuatu to clarify the distribution, growth environment and utilization of Metroxylon salomonense (Warb.) Becc. and M. warburgii (Heim) Becc.. Four po pulations of M. salomonense on Gaua in the Banks Islands and Malakula were found in this survey: one at the eastern site of Gaua and two at the northern site and one at the southern site of Malakula. M. warburgii grew on Gaua, Espritu Santo and Malakula. M. salomonense and M. warburgii were called as takur dun and tagura, respectively on Gaua. Contrarily Metroxylon palms were generally called as natangura on Malakula, while M. salomonense was occasionally recognised as wild natangura in an area in southern Malakula. On Espritu Santo, M. warburgii only distributed and was called as natangura. The soils at the growing sites of both M. salomonense and M. warburgii were well-drained, however soil moisture condition seemed to fulfill the water requirement of Metroxylon palms at each site. Native people had used sago (starch extracted from pith inside trunk) as an emergency food until the 1950s at least on Gaua, though sago was not used at all the sites. The most important contemporary use of Metroxylon palms is for house construction material such as thatch (atap) in Vanuatu and』M.warburgii is cultivated entirely to harvest the leaves for making thatch.

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 In this study on the effective utilization of sago residue, analysis of sago residue as a lignocellulosic resource was undertaken. The cellular components and the cell sizes in deconstructed sago residue were examined. These results showed that sago residue is predominantly composed of parenchyma cells (The occupation area ratio was approximately 85%). In addition, the fiber and vessel contents were low, and these elements were remarkably damaged. These findings indicate that the sago residue is not suitable as a source of raw fiber material. The various properties of sago residue as a powder sample, which include grindability, internal surface area, and crystallinity of cellulose and starch, were then evaluated. From these analyses, it was clear that sago residue is more easily ground than Sugi (Cryptomeria japonica), and the crystallinity index for cellulose was reduced after simple processing. In the sago residue, the value of the internal surface area is higher than that of regenerated cellulose. Because sago residue possesses these properties, sago residue is suitable for use as a powder raw material in chemical modifications.

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