Spatial distribution was analysed for all plot trees and representative tree species in two duplicate I-ha plots established in a foothill rain forest 16 km west from Padang, West Sumatra, Indonesia. All tree trunks ≥ 8 cm dbh were distributed randomly in both plots. Spatial correlation between dead trees and recruited trees during the 8-year period was locally negative while broadly positive, suggesting that the random spatial pattern is dynamically maintained by mechanisms of density-dependent regulation.
All of five abundant canopy/subcanopy non-pioneer species, i.e. Hopea dryobalanoides, Gonystylus forbesii, Cleistanthus glandulosus, Mastixia trichotoma, and Grewia florida, and typical pioneer Macaranga spp., including M. gigantea, M. hypoleuca, M. pruinosa and M. triloba, showed a clumped distribution, particularly for smaller size classes. Two subcanopy non-pioneer species, Mastixia and Grewia showed a shift from a regularly decreasing density with height in one plot with larger gap area to bimodal height distribution in the other plot with smaller gap area. They also showed a similar tendency in spatial pattern such that the negative spatial correlation was observed between seedlings (< 1 m high) and poles (1-10 m high) and between poles and tall trees (≥10 m high) in the plot with larger gap area but that was found between seedlings and tall trees in the plot with smaller gap area. Such pattern was also observed for gap-demanding Macaranga spp., and they were concluded to be less tolerant than Hopea, Gonystylus and Cleistanthus, in which no height distribution difference nor spatial pattern difference was observed between two plots. These more tolerant species showed a positive correlation between tall trees and seedlings, but no correlation between tall trees and poles. These results reflect the dynamic alternation of tree species within a limited area of forest.

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Horizontal variance of a stand structure and productivity in a tropical foothill rain forest was analysed with the dbh census data obtained from the successive observation for 8 years at a 1-ha forest stand in West Sumatra, Indonesia. Targets of the census were trees over 8 cm in dbh.
Individuals at each dbh class distributed randomly in horizontal pattern. The quadrat method based on the dimensions per some unit area showed that the aboveground biomass was higher aggregated in spatial distribution because of the strong influence of the scattered emergent trees. Main canopy trees being about 35 cm in dbh largely affected the horizontal distribution of leaf biomass and productivity, and the degree of contagion of these values was lower than that of aboveground biomass.
We estimated the stand structure and productivity around 2336 points in a plot, arranging systematically at intervals of 2 m, from the values per projection area of a tree covering each point. Bird’s-eye-view diagrams were presented to visualize the horizontal distribution patterns. The three-dimensional distribution of estimated relative illuminance showed the horizontal and vertical stratification in a 1-ha forest stand. The frequency distribution of biomass, productivity and relative illuminance at lower levels under 20 m in height could be approximated by the log-normal distribution. The coefficient of variance of productivity was higher than those of aboveground and leaf biomass. A simulation of the regeneration process at a gap site in a mature forest reproduced the high variance of productivity.

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The amount of litter fall in a mangrove forest at Phang-nga Bay on the west coast of Thailand was estimated by trapping the litter over a 12 months period. The average litter was 550 g dry weight m^-2yr^-1 of which 93 - 99 % was leaf material. The monthly maximum litter fall (82.76 g dry weight m^-2) was in January (the dry season) while the monthly minimum (24.0 g dry weight m^-2) was during July and August (the wet season). The average nitrogen and phosphorus supply analyzed from the leaf litter were 2.688 g m^-2 yr^-1 and 0.257 g m^-2 yr^-1, respectively.

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A study on the decomposition of mangrove senescent leaf litter was conducted at Khao Kao Canal, Phang-nga Bay. The collected leaves were distributed in litter bags and immersed in seawater for 12 months. The litter decayed rapidly in the first 6 weeks as determined by weight loss. The weight decreased to 30-60% of the initial leaf weight during this period. Thereafter, the rate gradually decreased. The litter completely decomposed within 8-12 months. It was found that the decomposition rate depended on the frequency of submersion as affected by the tide. Therefore, sites close to the mouth of the estuary showed a faster rate of decompositiop than those in the forest or upstream. Additionally, benthos fauna such as crabs, polychaetes, mollusks, amphipods and sipunculids found in the litter bags also played an important role in the degradation of mangrove litter. However, seasonal weather changes appeared unlikely to enhance the rate of decomposition.

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Body size was compared between queens and workers in two New Guinean swarmfoudning Ropalidia species, R. bambusae and R. leopoldi. Queens of R. bambusae tended to have longer mesosoma and larger metasoma than workers. Although the canonical discriminant analysis using nine morphological characters showed that there was only partial overlap between queens and workers, respective characters of them overlapped considerably if compared separately. Queen/worker size ratio within a colony for the mesosomal length was 1.02, which was smaller than inter-colonial difference. Although only one queen and seven workers were available for R. leopoldi, there seem to be distinct size dimorphism in this species. Queen/worker size ratio for mesosomallength was 1.16, and this value was comparable to that in R. montana, which has been known to represent distinct female caste dimorphism.

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Life histories of two cJupeid fish species (Stolothrissa tanganicae and Limnothrissa miodon) in northwestern Lake Tanganyika were studied. S. tanganicae spawns offshore all the year round but more actively in the first half of the year. This fish comes to be exploited by the Zairian artisanal lift net fishery at an age of about 2 months and length of about 3 cm in standard length, and attains 9.35 cm when one year old which approximates to its longevity. L. miodon enters into the exploited phase at an age of 2-3 months and length of about 3 cm, grows up to 9.24 cm when one year, and approaches to an asymptotic length of 13.5 cm. The two species grow to their maximum sizes slowly for their short longevity. They have lower proportions of gonadal weight to body weight than many other fish species, suggesting that they possess a lower level of reproductive effort. An increase in the mesh size of the commercial fishing net is effective in enlarging the exploitable fish biomass.

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The ethnobotany, particularly the relationship between people and forests, of the Dolok Sibual-buali Nature Reserve Area was studied. The villages around the Nature Reserve are traditionally established away from forests and agricultural areas and are inhabited by the Batak ethnic group. Within the village, houses are built closed to each other without home-garden. The village is usually surrounded by sawah (paddy-fields), ladangs, and forests at the outer edge. Five out of 15 villages around the Dolok Sibual-buali Nature Reserve are remote and far away from the center of community activities. The magnitude of dependency on the forest products of the people in the remote villages is relatively greater than do the people in the other villages. The people in the remote villages utilize the Nature Reserve as resources for traditional medicine, home industry, and daily needs such as food, including resources of traditional food industry, fire woods and construction materials.

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The Aka hunter-gatherers in northeastern Congo exchange various forest products with neighboring cultivators. While meat comprises an important exchange item in other forest areas of central Africa, it is rarely exchanged in the northeastern Congo region because of the spread of guns among the cultivators. Irvingia nuts comprise one of the most important exchange items, instead. Irvingia nuts are exchanged either in the form of nuts or the processed cake. The goods exchanged for the nuts are mainly agricultural products, whereas that for processed cake are manufactured goods such as pots and clothes. The nuts circulate within the village, and processed cake is traded to the area outside the village sphere as an important element of local and regional economies. The implications of these differences for the economic life of both the Aka and the cultivator are discussed.

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Two sets of rainfall records previously published by Indonesian institutions were summarized to examine regional difference and seasonality of rainfall in Java, especially sites in and around Bogor.

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