The stand structure of a mixed dipterocarp forest was analyzed by using the data obtained from a fifty-two hectare research plot at the Lambir National Park, Miri, Sarawak, East Malaysia. The range of data analyses in the present study was confined to the topics of physiognomy while awaiting species identification data. The forest height evaluated by a height curve model of a hyperbolic equation was the tallest in Lambir among three research sites, Barro Colorado Island in Panama, Pasoh in West Malaysia, and Lambir in East Malaysia. By dividing the 52 ha plot into 1300 stands of 20 m &time; 20 m, the physiognomic dimensions, such as the biomass, tree density, maximum dbh, and basal area per stand, were calculated and their dependency on topography was statistically tested. The results of statistical tests suggest that the significant differences of physiognomic dimensions between stands are marked by different topographic conditions in terms of slope altitudes, angles, directions, and convexity degrees. The correlated change in physiognomic dimensions and local topography implies the dependency of the relative occurrence of three growth phases (gap, building, and mature phases) in the forest growth cycle upon topography. The size structure of the stands was analyzed by using dbh data and by assuming the exponential distribution of dbh. The stands were characterized by stratified subpopulations, whose total number per stand was in a range between two and seven. The variation in the number of sub-populations per stand corresponded well to the altitude difference between stands, suggesting correlated gradients in the forest stratification, forest growth cycle, and topography. All these results suggest the presence of predictable change of the huge and complex architecture of the rain forest at Lambir in relation to topography or environmental conditions such as soil and water. In these respects, the results seem to be favored by an equilibrium hypothesis rather than non-equilibrium hypothesis as a working mechanism of tropical biodiversity, though floristic composition can be independent from physiognomic dimensions.

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The distribution of mineral elements in different compartments of trees grown in a mixed dipterocarp forest in the Lambir Hills National Park, Miri, Sarawak was studied. 514 samples mainly of leaves, twigs and trunks, partly of roots, barks and litter were collected from 101 different trees of 62 species of 25 families. The samples were analyzed for 28 chemical elements, i.e. N, K, Ca, Mg, Mn, Na, AI, Br, Fe, B, Sr, Ba, Zn, Rb, Cu, Ni, Co, Ti, Sc, Cr, Pb, Ce, Li, As, Cs, V, Mo and Th. Essential elements as N, K, Mg, Mn, Fe, Band Ni showed higher concentrations in the leaves. Ca, Zn and Cu were found significantly higher in the twigs. These elements are known to be related to the auxin metabolism effective to the induction of the cell lignification. The elements with no characteristic concern to any physiological processes behaved as if they underwent passive uptake. The uptake of elements with toxic or negative effects to plants, e.g., AI, Pb or As seemed to be either blocked by the roots or they were safely stored in those organs as trunks and barks. Taken the fact into account that those elements actively associated with plant physiological processes are accumulated in the living plant organs, due attention should be paid to the high concentrations of Ba (Gluta oba), Co (Koilodepas laevigatum, Trigonostemon capilli pes , Allantospermum borneense) or Sr (Koilodepas laevigatum).

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The distribution of mineral elements in tree leaves of a mixed dipterocarp forest was studied on a plot in the Lambir Hills National Park, Miri, Sarawak. Special reference was given to specific accumulation and exclusion of a certain element. In total 237 leaf samples of 103 different trees from 62 species of 25 families were collected and their element composition was analyzed. The elements determined were N, K, Ca, Mg, Mn, Na, Fe, AI, B, Ba, Sr, Br, Zn, Rb, Cu, Ni, Ti, Cr, Sc, Pb, Co, Li, Cs, As, V, Ce, Mo and Th. Accumulator species were defined as such tree species which showed a higher concentration than the mean concentration of an element plus twice the standard deviation, excluder species as tree species with lower concentrations than the mean minus twice the standard deviation. The Ca concentration of the leaf samples were in general low with a mean value of 0.38 %. Trees of Dipterocarpaceae showed less accumulative nor exclusive tendency. Accumulators were Gluta oba for Ba, Mallotus sp. for Mn, Allantospermum borneense for Co, Koilodepas laevigatum for Ca, Sr, Co and Trigonostemon capilli pes for K, Mg, Ni and Co. An accumulation of AI by Memecylon sp. (Melastomataceae) corresponds with Masunaga's findings (Masunaga et al., 1995). In Markert (1993) Melastomataceae are recognized as Al accumulators. Co showed a specific distribution. Excluders could not be discriminated from the definition. However several species were found below the detection limit for Br, Mo, Li and Th. The wide range of element distribution in the rain forest canopy reflects the enormous diversity of absorptive or exclusive characteristics of elements among the tree species.

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Avicennia marina seedlings were grown at 7 different levels of seawater (0, 25, 50, 75, 100, 125 and 150% seawater) in the greenhouse. The effect of external salinity on the early developmental stage of A. marina was studied by examining germination, the growth performance and photosynthetic rate. At lower salinity seed germination took place quickly and the germination percentage was higher than that in higher salinity. The optimal growth was recorded in 25% seawater. In the sodium chloride free medium the growth of seedling was inhibited. High salinity caused the increase of fallen leaves and decrease of the growth performance. However, all seedlings appeared to have grown up in higher external salinity. The photosynthesis was affected by external salinity, but A. marina could maintain the positive photosynthetic production at higher external salinity of 125 and 150% seawater. In conclusion, though salinity is an important factor which affects the establishment and growth of a seedling, A. marina appears to be an effective salt tolerant plant species.

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The salt tolerances and initial growth of Kandelia candel and Rhizophora stylosa of mangrove plants were examined in different salinity conditions. The natural growth of K. candel and R. stylosa seedlings in the Oura and Kesaji Rivers, the effects of a treatment of quick change from fresh water to saline water, and the recovery experiment of nutrient deficiency were researched.
The growth inhibition occurred in 1.8% sodium chloride treatment, both in K. candel and R. stylosa seedlings. An increase in chlorophylls content and leaf thickness appeared in saline treatments. This shows a character of regulator halophyte. The result suggests that appropriate salinity is one of the important factors of both mangrove species. In natural seedlings, cation concentrations were similar to that of cultivated seedlings grown in 1.8% salinity. This indicates that the cation concentration analyzed in this experiment is not a limiting factor for their salt tolerance. Nutrient deficiency appeared only in the cultivated condition. By the spraying of a urea solution, the seedling can recover its original good condition. Hence, it suggests that ammonium form ion as a nitrogen resources is a very important factor for their growth.

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Diet and ranging patterns of gorillas (Gorilla gorilla graueri) and chimpanzees (Pan troglodytes schweinfurthii)were studied during the 1994 dry season in the montane forest of KahuziBiega National Park. A transect census was also made to estimate the diversity and density of trees in primary forest, secondary forest and swamp. Although the diversity of trees in this area was lower than those estimated in lowland tropical forest, more than half of the total 50 tree species were used for foods either by gorillas or by chimpanzees during the study period. A semi-habituated group of gorillas and a unit group of chimpanzees extensively overlapped their diet and ranging areas, but gorillas tended to consume fibrous foods qualitatively and quantitatively and to range in wider area than did chimpanzees. Gorillas daily traveled in both primary and secondary forest to avoid reuse of the previous ranging areas, while chimpanzees persistently range in a small patch of primary forest. The diversity and density of food trees with bearing fruits were higher in primary forest than in secondary forest, and both apes preferred the fruit species which trees appeared at low densities in the transect. The low density of chimpanzees may be owed to the small size and fragmented distribution pattern of primary forest in this area. The differences in foraging patterns between gorillas and chimpanzees may reduce ecological competition between them.

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Biology of Sumatran Xystrocera globosa, a stem boring cerambycid pest of leguminous trees, was studied by laboratory breeding. The larvae were fed an artificial diet and kept either singly or in groups. Patterns of development and survivorship in immatures and survivorship and fertility in adults were described quantitatively. The larvae established better in group rearing than in isolation, but showed cannibalism in groups from the 2nd instar onwards. Semel parous nature in reproduction was noted.

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Thirty eight species belonging to 12 mutillid genera are recorded from Borneo and neighbouring islands. Yamanetilla gen. nov. (type species: Odontomutilla nipponica Tsuneki), Petersenidia dayak sp. nov. from Sarawak, Sinotilla lambirensis sp. nov. from Sarawak, Smicromyrme borneo sp. nov. from Sabah, Andreimyrme sarawakensis sp. nov. from Sarawak and hitherto unknown female of Trogaspidia cydippe (Mickel) are described. The genus Radoszkowskius Ashmead (type species: Mutilla simplicijascia Sichel et Radoszkowski) is resurrected in the tribe Trogaspidiini.

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Deforestation in tropical forest is continuing, and may be a cause of global environmental problems. Yet how the deforestation effects the environment is somewhat obscured. As a first step, an investigation of the differences of environmental characteristics between a natural tropical forest and deforested canopies has been conducted.
Some measurements in a tropical swamp forest, a secondary forest, and a reclaimed paddy field in Narathiwat province, Thailand have been carried out.
The measurements are made to clarify energy and mass exchange rates between the canopies and the atmosphere using micrometeorological methods. In the forest, those measurements are being conducted from a 38 meter-high observation tower constructed in June, 1992.
Results obtained show that the deforestation of the tropical swamp forest undoubtedly changes the micrometeorology. In particular, the changes clearly appear in heat, water vapor, and carbon dioxide which are transported especially during the dry season. It was proved that a newly developed system to estimate gas flux by using the eddy accumulation theory shows excellent performances to promise reliable gases fluxes measurements in natural environment.

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A study of ‘baribhita’ (homestead in English) and its utilization was conducted in a village 100 km north of Dhaka, situated on a natural levee of the Old Brahmaputra floodplain. A typical ‘baribhita’ consisted of ‘uthan’ (middle yard), ‘jongol’ (back yard), and ‘pukur’ (tank) in front of the ‘uthan’. ‘Uthan’ was a well maintained open space and was used as a space for postharvest processing and daily life. Various fruit trees and vegetables were planted and livestock were kept there. In contrast to ‘uthan’, ‘jongol’ was less tenured and many wild plants grew there. ‘Pukur’ was a place for bathing, washing and cooking. It was also utilized for fish culture which became popular because of its high profit. Palms and vegetables were usually grown around ‘pukur’.
‘Baribhita’ was a very important place for tree plantation in the floodplain, and for planting vegetables in the rainy season as well. Fruit trees were also intensively planted for multiple purposes. Most vegetables grown were of the creeping type. Under the vegetable trellis or in ‘jongol’, shade-tolerant plants and seedlings of fruit trees were planted. All of these plants made full use of the limited space of ‘baribhita’. ‘Baribhita’ played an important role in providing villagers with daily necessities.

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Sri Lanka has a long tradition of forest conservation. Colonial powers exploited the country’s forests yet, since the late 1800s modern conservation was begun by the British. Today about 14% the land area is under complete protection and in the recent past protected areas as well as forest plantations have increased despite that natural forest cover has plummeted to about 22% of the land, area. Institutional deficiencies and some agricultural practices and illicit fellings pose threats to forest conservation in Sri Lanka. However overall situation does not seem to be unsatisfactory.

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Fern species composition and fern community were observed at oil palm plantation and adjacent natural forest near Kuala Lumpur in Malaysia, with respect to tree size and structure. Sixteen fern species were found on oil palm trunks. Six species of Nephrolepis biserrata, Davalia denticulata, Vittaria ensiformis,Asplenium nidus,A. glaucophyllum andA. longissimum are common on various sizes of oil palms (1-8.5m height). Early invasion of fern community on oil palm trunks is conducted by N. biserratas and D. denticulata. Microhabitat of N. biserrata seems to be a sunny site while that of V. ensiformis a shade site on oil palm trunk. Fern species composition and frequency change during oil palm development and with different height. A. nidus sometimes (19% of tall and 3% of all trees) occurs in natural forest; and invades on oil palms exceeding 4m height. A. nidus seem to be a micro-ecosystem for some insects. Such vertical vegetation cover by epiphytic ferns on tree trunk seems to contribute a high phytodiversity at narrow site and insect biodiversity as well as canopy in tropical rain forest.

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The genetic structure of Shorea macrophylla in Sarawak was examined by using allozyme variation. Fifteen seedling families each originated from a single mother tree, henceforth called families, were selected at west and central Sarawak. Leaves were sampled from 30 seedlings per family, and were subjected to allozyme analysis. Percent of polymorphic loci was 43% and the mean heterozygosity (H_e) of the species was 0.209. The UPGMA cluster analysis conducted for the fifteen families extracted three genetic clusters, which were accordant with three geographic ranges, Kuching, Sri Aman, and Bintulu, respectively. G_ST for these three populations was estimated as 0.208, meaning 20.8% of total genetic diversity occurred in the variation among three populations. Thus the genetic structure of S. macrophylla was characterized by moderate genetic diversity within species and high genetic differentiation among local populations.

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Lindernia crustacea, a nectarless but zygomorphic tropical herb with solitary inflorescences, increased flowering in prorpotion with biomass accumulation after a doubling of atmospheric CO₂, compared to control plants. Pollen grain number and size, per flower, was no different, while pollen viability was lowered slightly by the elevated CO₂ treatment. Mean number of flowers produced during a three week period, flower dry weights, shoot and root dry weights all increased by 22-34% under elevated CO₂. Statistically, only root biomass, pollen viability and individual rate of flower production were substantially affected.

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