Phytosociological study, based on Braun-Blanquet, was conducted to investigate actual vegetation in suburban areas of Bangkok. The results show that the plant communities of the study areas can be classified into 5 categories: 1) aquatic plant communities; 2) grassy weed communities; 3) quasi- natural forest communities; 4) secondary forest and mantle communities; and 5) an abandoned fruit orchard community. These communities involve 69 plant families, in 144 genera, and 188 species. The most characteristic communities were quasi-natural forests, such as the Dipterocarpus alatus community, Salix tetrasperma community, Erythrina fusca community, and Syzygium cumini-Elaeocarpus hygrophilus community. This report is the first description of these communities in suburban areas of Bangkok. The Salix tetrasperma community, in particular was not known in the tropics. The landscape in general, as well as remnants of natural vegetation, has been changed by human impact. For example, agriculture areas have been converted to residential areas and industrial areas. Wetlands and swamps have been reclaimed for golf courses and general infrastructure. The reason is the rapid urbanization, which encroaches into suburban areas. In addition, natural vegetation was replaced by substitute vegetation in degraded areas.

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Successive changes of stand structure and primary productivity of a ropical secondary forest from clear cutting were studied through long-term observation during 12 years from 4 years later after the event in a foothill rain forest area of West SumaEa, Indonesia.
Species number of trees over 5 cm dbh at the initial observation ranged from 30 spp. to 40 spp. per a stand being under 1000 m² in area, and this value was less than half of one in a matuled forest stands with same area. The secondary forest had some prominently dominant species derived from germination after the last logging. Growth rate of biomass was largely different among sites, and a sund on fertile soils conditions grew up to 300 metric ton ha^-1 in aboveground biomass within 9 years. Many canopy trees in the forest, however, rapidly died at the latter phase of this observation, and Eees sprouted from logged stumps and species in a matured forest both increased their dominance relatively. Frequent logging would be to the advantage of species having coppice generation because ofpositive correlation between a stump size and growth rate of shoots.
Hardness of stem wood of secondary species tended to be lower than one of matured forest species, and the property had a positive conelalion with relative growth rate of dbh (RGRD) for secondary species. A mathematical model based on this relation suggested that amount of photosynthetic product of a tree would not be largely different irrespective of stem hardness under similar external and internal conditions, and a tree would allocate the product to suitable positions for the growth ofvolume or bulk density based on is life srategy.
A time rend of a primary net productivity had the maximum value within a few years after logging, and tended to be constant. The value at the stable stages was not sigrificantly different from one of a neighboring matured forest, and was estimated at26 - 30 metric ton ha^-1 y^-1 as total primary productivity including roots. The RGRD - dbh of a stand largely changed with time on regeneration process, and it produced the maximum productivity at the initial stages. Basing on this time rend of this relation, we analyzed successive changes of stand structure and primary productivity under consideration with effecs of stem hardness of a Eee as physical property.

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An ecological study on the Ruteng Nature Recreation Park (TWA Ruteng), Flores Island, Indonesia was conducted with intent to obtain accurate and current information on the forest such as structure, species distribution and diversity, and aititudinal zonation in the island. Data were collected from quadrants taken at every 20m on line transects horizontally set up at an altitudinal interval of 100m in following five sampling sites, Lempang Paji, Uluwae, Mano, Ponggeok and Mocok in the TWA Ruteng.
Forest stands of TWA Ruteng were classified approximately into three groups or forest zones. The lowest group is only found at 520m in altitude at Mocok, and is a lowland tropical forest represented by Artocarpus elasticus and Canarium asperum. The second is a submontane forest between 800m and around 1500m. This group was assemblage of various forest types. Upwards from 800m, Celtis tetrandra-Itea macrophylla, Villebrunea sylvatica-Talauma sumbawensis, Elaeocarpus sphaericus- Mallotus philippinensis, Palaquium obovatum-Cryptocarya densiflora, Platea excelsa-Elaeocarpus floribundus, Pagiantha sphaerocarpa-Acer niveum, Pittosporum moluccanum-Palaquium obovatum, and Chionanthus ramiflorus-Litsea resinosa stands were recognized, and there were considerable number of common species among those forest stands. Two types of montane forest, Planchonella nitida-Platea excelsa stands at Uluwae and Ponggeok and Acer niveum-Chionanthus ramiiflorus stand at Mano, were recognized from 1500m to 2100m, but the last stand has a number of common species with high value of importance among the former stands. A number of forest types in the lowland area have a trend of convergence into a few types in higher altitudes with replacing species.
The highest value of total basal area reached 1 % of plot area at 1700m asl. at Ulwae. Mean basal area of a tree was low in high density ranges, but it gradually increased with decrease of density. A plot of an afforestation which has been kept naturally after planting, has low value of it, too, but its process of increase will follow in another way.
Forests between 500m and 1000m in altitude are usually confined with villages, and the villagers have exploited forest resources for their daily life. Their exploitation has been extended upwards into higher altitudes than 1000m. One example has kept in the forest as an Eucalyptus urophylla plantation. Ruteng forest should be protected more strictly for promoting people's health and for recreation than in the past.

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To survey geographical variation of taro, Colocasia esculenta (L.) Schott, isozyme variation was examined in 120 accessions of taro from China, Taiwan, the Ryukyu Islands, and Japan. The accessions were assigned to 12 groups, based on their isozyme phenotypes of PGM, SkDH, AAT, and ADH. Cluster analysis classified Japanese triploid accessions into four larger groups, and this classification agreed with previous studies. The triploid accessions classified into the same groups were found in Taiwan, the Ryukyu Islands, and Japan or in China and Japan. The geographical distribution suggested two different dispersal routes of triploid taro into Japan. One route was through Taiwan and the Ryukyu Islands, and the other directly from China. It was suggested that these routes might be characterized by some Japanese cultivars.

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We studied the population dynamics of two species of tortoise beetles, Aspidomorpha miliaris (AM) and A. sanctaecrucis (AS) (Coleoptera: Chrysomelidae: Cassidinae), feeding on a shrubby morning glory, Ipomoea carnea (Convolvulaceae), in Purwodadi Botanic Garden, East Java, Indonesia. Rainfall in Purwodadi is distinctly seasonal with 5-7 months of harsh dry season, lasting from March or April to October or November. In March of 1993, we established three study sites by planting 10 cuttings of the host plants on each site. We carried out a weekly census including mark-recapture of adults with color paints and construction of life tables for immature stages, from June 1993 to March 1996. Total number of leaves on the study sites increased during the wet season and decreased during the dry season, although effects of dry seasons on the change in the total number of plant leaves depended on the site condition (sunshine and water). We marked all beetles found on the sites (136 and 436 beetles for AM and AS, respectively). Adult populations of the two species increased in the rainy season, decreased as the dry season started, and disappeared in the late dry season. Seasonal trends in the adult numbers mainly reflected the oviposition activity of adults, which was high in the rainy season and diminished or nil in the dry season. The sex ratio was 1:1 in AM and largely female-biased in AS. Average adult residence time (days) on each site was 6.6 (male) and 8.1 (female) in AM and 7.0 (male) and 9.8 (female) in AS. The current results are discussed with our previous data of the two species in two localities with higher and less seasonal rainfall conditions, Padang (central Sumatra) and Bogor (West Java).

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A new species of the army ant genus Aenict"s is described from Sarawak, East Malaysia. This Bornean species is remarkable in having a polymorphic worker caste, and an inflated propodeum filled with red liquid in larger workers. The smaller workers possess narrower heads with the sides almost parallel, very short antennae and legs, and normal propodea. They were few in number and their function in colony organization is not known.

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