It would be fair to say that knowledge of the forest types of lowland tropical Asia is greater than that of the neotropics, but not as complete as that of Africa, where the integrative role of A.E.T.F.A.T. (1959) has set an example that no other continent has so far succeeded in emulating. This collaboration resulted in continental vegetation maps of unprecedented uniformity and precision. Two pioneering efforts do exist in Asia though, which provide a basis at least for reviewing what we know, and drawing up a schematic classification as a basis for discussion and refinement. These are the landmark and remarkably detailed preliminary survey of the Forest Types of India and Burma (Champion, 1935), and its revision for modern India alone with S. K. Seth (1968); and the magnificent mapping program of the Institut de la Carte lnternationale du Tapis Vegetal, the University of Toulouse, and the French Institute at Pondicherry. Both rest on a combination of a wealth of personal experience on the ground, and a rather comprehensive though inevitably regionally patchy literature, equally essential for success. The comprehensive forest working plans which have been and remain a tradition of India, and formerly Burma, were particularly important sources of ground information.
Champion & Seth’s classification (Table 1) gives primary emphasis to physiognomy including leaf phenology, and structure including life forms and morphological characters, with less emphasis on species composition and dynamics. This was done explicitly in recognition of the influence of historical biogeography on the former, and of the confounding effects, and often local specificity of successional vegetation, widespread though it was even then. Their approach indeed provided a regional frame. But the downplaying of dynamic aspects led to a static rigidity which has made it inadequate in an era of actively managed, not to say degraded forests. The subordination of floristic information, and even of dominant species, to structure and physiognomy has obscured major regional differentiations which are related to geology and soil, rather than to climate and climate-correlated factors such as fire.
The Pondicherry group have consciously attempted to address both these shortcomings. Their method depends, first, on a classification of climate on criteria found, by empirical experience in many regions of the world, to be the most correlated with vegetation: Mean temperature of the coldest month, annual rainfall, and length and number of dry seasons. Second, it depends on comprehensive ground truth, extrapolated by means of aerial photographs, which has permitted use of dominant species as a major basis for their vegetation classification. In effect, soils-correlated variation on geographical scale is thereby incorporated, though the necessary soils survey data to define the interrelationship between vegetation and soil often does not exist. Comprehensive ground truth has also provided the means to more completely understand the dynamic relationships between different vegetations, and to more rigorously identify seres. The Pondicherry group have now extended their work from India including the Himalayas, and Cambodia to Indonesia, where they have published ‘bioclimate’ maps for Sumatra and Borneo, and a vegetation map of Sumatra.

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Studies on the early secondary succession were carried out in a lowland mixed Dipterocarp forest and a kerangas (heath) forest in East Kalimantan, Indonesia. The results show that there is a correlation between the species strategy with the physical and chemical soil status in the early secondary succession. In Mixed Dipterocarp Forest (Red- Yellow Podzolic soils) seedlings of secondary species were important as the initial colonizers. In contrast, vegetative resprouts (trees and shrubs) were the main component of Kerangas Forest (Podzol soils). A model of species strategy in relation to changes in soil property associated with the early secondary succession is presented.

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Effects of density on plant growth and self-thinning process were studied in tropical forest plantations of Melia azedarach and Azadirachta indica from one year-old to six year-old. The density levels were controlled by changing the initial tree number per area from 625 trees ha^-1 to 40000 trees ha^-1 and l57 trees ha^-1 to 40000 trees ^-1 for M. azedarach and A. indica, respectively. The density dependent mortality was remarkable in M. azedarach plantations. But it was not evident in A. indica plantations which had slow growth on very poor soil. The ω-ρ relationship and ω-ρ trajectories were approximated by Hozumi’s model. The coefficient values of the model were compared with those of former results from Eucalyptus camaldulensis and Pinus strobus. The β value of the model for M. azedarach and A. indica differed from 3/2 which expected from the Yoda’s 3/2 power law. This seemed to be due to the lack of severe death of individual trees in all plots during the period of the study. The growth of these two species followed the general logistic growth curve which was characterized by changing asymptotic tree size and intrinsic growth rate during the growth period. The lag time for both species was equal to zero. There was no distinct difference in maximum biological time between these species.

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Thrinchostoma asianum sp. nov. is described from Sumatra as the first record of the subgenus Diagonozus known by four African species. T. asianum shares the unusually long lower part of the head with these species but is less differentiated in some features. This species is probably oligo-trophic to Impatiens korthalsii flowers.

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Flowering patterns and pollination syndromes were compared among four sympatric Impatiens species (Balsaminaceae) in tropical montane rain forests in Sumatra, Indonesia. Pink flowers with long filiform spurs of I. platypetala produced nectar of 26 % sugar both in the daytime and at night and were po11inated by crepuscular hawkmoths, Macroglossum corythus. Yellow flowers with gradually tapering spurs of I. korthalsii, I. talangensis and I. eubotrya produced nectar of 34-39 % sugar, mainly in the daytime, and were po11inated by two specialized long-tongued anthophorid bees and an unusually long-tongued halictid bee. Spur morphology essentially determined nectar accessibility. Although the three Impatiens species partially shared the three bee species, they partitioned their po11inators by differing in sites of pollen deposition on the bee's bodies. The low po11inator visitation rates per day were compensated by the extended flowering period of the four species. Nectar robbing by two anthophorid bee species was observed, for the first time in Southeast Asia.

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The height and numbers of pneumatophores of a mangrove, Avicennia marina, were investigated under different levels of plant densities and flooding water level on an experimental stand. Initial plant densities were assigned to four levels, 30, 45, 89, and 260 plants per square meter. After two years and nine months, water levels were changed to keep ground level (control), and 9cm above ground (flooded). The average numbers of pneumatophores per plant under lower plant densities were greater than those under higher densities. Pneumatophores became longer in height and greater in number when the plants were kept under flood. The total numbers and the rate of increment of pneumatophores of the higher density pots under flood well exceeded the numbers of the lower density pots under control. It was concluded that the pneumatophores of A. marina were highly responsive to water level.

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Mangroves in general, and estuarine wetlands in particular, perfonn a number of biological and hydrological functions that are economically valuable and benefit society. Over 4.25 million ha of mangroves in Indonesia are today listed by the Department of Forestry as being of national importance. Based almost exclusively upon the ecological importance of mangrove forest for the fishery sector, the appreciation of nursery values has made a major contribution to mangrove conservation (Sukardjo, 1990). Today, however, as the cumulative importance of mangrove wetlands is increasingly realized, and while threats to mangrove environment increase (e.g., in Java), the case for mangrove conservation has begun to rest increasingly upon the demonstration of other functions and services which Indonesian mangrove can provide to human society (Sukardjo & Toro, 1988).
Mangrove swamps are facing long-tenn impacts from a range of both man-made and natural causes. Man-made impacts caused by agriculture, coastal development, industry and resulting pollution will continue to be significant in many areas. Natural phenomena related to climatological and localized conditions, such as sea level rise, and subsidence, will also have significant impacts especially when they are combined with man-made impacts. Visual-cultural values are the finite natural resources available for human use or perception which are within, or associated with, mangrove areas.

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