Dynamics of N₂-fixing bacteria such as Rhizobium, Azospirillum and Azotobactor, nodule number in the dominant legume Atylosia trinervia and P-solubilizing bacteria, actinomycetes and fungi were determined for two years in unburned and burned sites of a natural grassland, southern India. Populations of all Nz-fixing bacteria and nodule number in the dominant legume Atylosia trinervia significantly increased in burned sites. P-solubilizing bacterial and fungal populations were also increased significantly by surface fire but actinomycete population remained unaltered. Thirty six species of fungi were recorded with tricalcium phosphate solubilizing ability. The population densities varied between sites according to individual species. The burned site recorded significantly higher fungal propagules than unburned site. The most efficient P-solubilizing fungi were Absidia ramosa, Gongronella butlerii, Mortierella spinosa, Mucor racemosus, Rhizopus nigricans, R. stolonifer, R. oryzae, Aspergillus furnigatus, A. nidulans, A. niger, Thielavia terricola and Cheatomium lunasporium.

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Concentrations of 15 mineral elements - S, K, Al, Ca, Mg, Cl, Si, Na, B, Cu, Fe, Mn, P, Sr, and Zn - appearing in 457 bark samples of trees in a 1 ha observation plot in West Sumatra, Indonesia, were analyzed. Based on the analytical results, an elemental non-accumulating tree was defined for each element as a tree with its concentration of the element in question within the bottom 5% (in this case 23 trees) of the 457 samples, irrespective of tree species. The relationships between the spatial distribution of the non-accumulating trees and the soil edaphic status at two depths (0-5 cm and 5-15 cm) were studied.
The non-accumulating trees of K, Al, Ca, Na, B, Cu, Mn, Sr and Zn tended to be distributed in areas where the concentration of those extractable elements in the soil was low. This indicates that a positive association between the soil edaphic status and the nutritional characteristics of the tree bark existed, as demonstrated by the distribution pattern of these non-accumulating trees. On the other hand, the distribution of the non-accumulating trees of S, Mg, Si, Fe and P was rather independent of the soil edaphic status of those elements, suggesting that the distribution of these non-accumulating trees was affected more by genetic factors or by environmental factors other than the soil edaphic status of those elements.
The relationship between the elemental concentrations in the bark and in the soil was also studied. A significant positive correlation was observed for K, Mg, Na and Sr, and a significant negative correlation was observed for B, Mn and P among the 457 trees, suggesting that those elemental concentrations in the bark were strongly related to the soil edaphic status. The non-accumulating trees of K, Na and Sr were distributed in the areas with the low and narrow elemental concentration range in soil, suggesting that the low edaphic levels seemed to strongly contribute to the low concentration level in the bark. However, in terms of the other accumulating trees and non-accumulating trees, the concentration levels in the bark were considered to be regulated not only by the soil edaphic status, but also by the tree genetic characteristics.

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For the rehabilitation of the degraded and abandoned land in the tropical area, it needs to define the various characteristics of remaining natural forests. This work was done to find out a physical hazard for root elongation of plant at Lambir Hills National Park, Miri, Sarawak, Malaysia, with special reference to soil hardness and soil texture. Furthermore, soil moisture and soil temperature were monitored at the hill ridge and at the valley to show their annual fluctuation. Soil physico-chemical properties at the hill ridge and the valley were also investigated.
At the hill ridge, well-developed soils with a deep solum were found. Organic matter content was high only at the surface horizon (0-5 cm) where a root mat develops. Although soil moisture content fluctuated significantly, the soil was dry throughout the monitoring period. On the other hand, at the valley, soil moisture content was relatively stable even after the frequent rainfall. The small particles and nutrients at the valley have been brought by the continuous water and eroded particles supply from surroundings.
Based on the topographical investigation, the study area was roughly divided into 3 categories:
1) Steep slope area : Soil and vegetation status may be often affected and modified by the land slide or soil erosion. Soil texture was sandy loam, loamy sand, or loam. Gravelly materials often appeared in the subsurface layer at the depth of 20-40 cm, which are hard for root to penetrate into. This layer can be regarded as the one with physical hazard against root penetration.
2) Gentle slope area : Soil and vegetation status are relatively stable for a long time. Soil texture was light clay or heavy clay. Transported clayey materials were accumulated to a depth below 20 cm, and/or the in-situ weathering in the deeper part could have occurred because of the relatively stable topography.
3) Ridge area : Although soil and vegetation status looks stable in view of topography, moisture condition much fluctuated. Soil texture was clay loam or sandy clay loam, which was the middle range between that of a steep slope area and a gentle slope area. The physical hazard in the soil might not be found, but the rates of root elongation and plant growth may be slow since the soil is prone to be dry.

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For the rehabilitation of the degraded and abandoned land in the tropical area, it needs to define the various characteristics of remaining natural forests. This work was done to find out a physical hazard for root elongation of plant at Lambir Hills National Park, Miri, Sarawak, Malaysia, with special reference to soil hardness and soil texture. Furthermore, soil moisture and soil temperature were monitored at the hill ridge and at the valley to show their annual fluctuation. Soil physico-chemical properties at the hill ridge and the valley were also investigated.
At the hill ridge, well-developed soils with a deep solum were found. Organic matter content was high only at the surface horizon (0-5 cm) where a root mat develops. Although soil moisture content fluctuated significantly, the soil was dry throughout the monitoring period. On the other hand, at the valley, soil moisture content was relatively stable even after the frequent rainfall. The small particles and nutrients at the valley have been brought by the continuous water and eroded particles supply from surroundings.
Based on the topographical investigation, the study area was roughly divided into 3 categories:
1) Steep slope area : Soil and vegetation status may be often affected and modified by the land slide or soil erosion. Soil texture was sandy loam, loamy sand, or loam. Gravelly materials often appeared in the subsurface layer at the depth of 20-40 cm, which are hard for root to penetrate into. This layer can be regarded as the one with physical hazard against root penetration.
2) Gentle slope area : Soil and vegetation status are relatively stable for a long time. Soil texture was light clay or heavy clay. Transported clayey materials were accumulated to a depth below 20 cm, and/or the in-situ weathering in the deeper part could have occurred because of the relatively stable topography.
3) Ridge area : Although soil and vegetation status looks stable in view of topography, moisture condition much fluctuated. Soil texture was clay loam or sandy clay loam, which was the middle range between that of a steep slope area and a gentle slope area. The physical hazard in the soil might not be found, but the rates of root elongation and plant growth may be slow since the soil is prone to be dry.

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To clarify the soil-plant relationship in the Sakaerat Environmental Research Station (SERS), northeast Thailand, soil survey was conducted in the two major types of forest, i.e., dry evergreen forest (DEF) and dry dipterocarp forest (DDD. In addition, DDF with fire protection treatment since 1967 (FPDDD was also selected as a study plot to know the effect of protection of land cover during dry season on both soil and vegetation. As a result of the soil analysis, such as soil hardness, soil morphological, physical, chemical, and mineralogical properties, the current vegetation in the SERS seemed to be affected greatly by the strength of the impacts (fue) given to the forest. If no fire protection is attempted in the DDR soil erosion due to loss oforganic matter on the surface soil is easily brought about. Soil properties such as clay content and associated properties (water holding capacity, cation exchange capacity, water penneability, and moisture content) become worse easily and shortly, after soil erosion.
The various soil properties of the FPDDF can be considered in the intermediate condition between those of DDF and DEF. The stronger the impact of fire is, the more the soil erosion occurs. On the basis of soil properties, the following mechanism can be suggested to explain the current vegetation; once the original vegetation was desroyed, DEF type forest could not regenerate easily in such a dry and infertile soil condition, and therefore, the other type of vegetation, i.e., DDF, is found elsewhere in northeast Thailand at present. The extremely dry soil condition currently found in the DDF is not intrinsic property of a forest soil. It is created by the removal of the vegetation which used to be there. The fire protected DDF suggests it.

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Studies on hydrobiogeochemistry were carried out in a hill-evergreen forest in northern Thailand. In this study forest climate conditions are characterized by a clear seasonal pattern of precipitation with dry and rainy season. Chemical properties of precipitation, throughfall and drainage waters were measured from December 1993 through February 1995. During the study period, annual precipitation was 2184 mm in the rainy season from March to October. Annual throughfall was 2936 mm. Higher throughfall would be attributed to fog interception by the canopy. Elemental fluxes in bulk precipitation and throughfall were high in the early rainy season from March to May. Elemental concentrations in forest drainage water of this watershed were in the lower range of concentration reported in other studies for tropical forests. Especially, Ca²⁺,Mg²⁺, Cl^- and NO₃^- were very low concenfiations. For SO₄^2-, NO₃^-, NIH⁴⁺ and Si concentrations in drainage water declined in the rainy season and increased during the dry season. These results suggest the minimum element losses from this tropical watershed.

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Solute input and output budgets were evaluated for an evergreen broadJeaved forest in southem China. Inputs and outputs varied with season, and were linked to water flux pattems. During spring to early summer with high water flow, solute output increased especially for base cations, HCO₃^-, and Si. The sulfur that accumulated in the watershed (723 eqlhaly) were probably derived from atmospheric sources in the urban and industrial areas in the southwestern part of China. Considering internal cycling, nitrogen was highly retained in the soil (409 eqlha/y). Loss of K was inhibited by internal cycling. Sodium was not held tightly in this ecosystem. For Mg, content in vegetation was high, but production by weathering was also important. Atmospheric Ca input contribute to higher output of Ca.

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To assess the current population dynamics of trees in an isolated 100-ha tropical forest fragment in Singapore we censused all trees >=1 cm dbh in a 2-ha permanent plot in 1993 and again in 1995 (N=13,470). We then examined the pattern of recruitment into the 1 cm dbh size class, comparing recruits to the existing flora and comparing recruitment rates among species to test hypotheses about patterns of short-term change. The overall plot recruitment rate was 6.5 % (annualized rate of 2.6 %), comparable to recruitment rates found in tropical forests elsewhere in the world. The hypothesis that species diversity is declining was found to be untrue, the recruitment class had a slightly elevated diversity compared to the existing 1-3 cm dbh class. When we classified species by abundance class, floral form, dispersal form, stature class and successional status, we found no evidence that abundant species are becoming more abundant, nor was regeneration of dioecious species repressed, and all stature classes were replacing themselves at similar per-capita recruitment rates. There was no sign of successful invasion by secondary forest species and the majority of secondary forest species in the canopy show no evidence of replacing themselves. The only evidence of biologically significant change among recruits was in regard of dispersal syndromes. We found that species with abiotically dispersal (both Dipterocarpaceae and non-Dipterocarpaceae) showed per-capita recruitment rates of over 10 %, compared to 6.5 % for biotically dispersed species. However, comparative data from large forests suggest that these high rates may be generally characteristic of these species. In contrast, the family Myristicaceae, rich in species and individuals, and closely associated with dispersers now extinct in Singapore, showed a recruitment rate of only 2.5 %, far below what comparative data from unfragmented forests portray as characteristic. Thus, in contrast to the bird and mammal populations, for which over half the species have been lost in the last 150 years, our data on the current short-term dynamics of trees reject the hypothesis that most species of Bukit Timah are in the midst of rapid decline.

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Environmental revisionists see the local landscape as a product of centuries-long interaction between man and nature. Based on this standpoint, examined in this essay is the ecological and ideological relatioship of the Mbuti hunter-gatherers of the Congo Basin with the forest world. While human activities are generally thought to be destructive to the environment from a conventional Western viewpoint, an examination of the Mbuti case indicates that they also impose positive impacts on the forest environment. A preliminary analysis of their use of forest and its resources suggests that their habitation and activities in the forest may have contributed to the maintenance of the forest resource base, rather than deteriorating it, and that they comprise a part of a large recycling sysytem of the forest world. The “circulation in the forest”, or “continuity with the forest”, shown in the ecological sphere is also represented in their view of the forest. The Mbuti view the forest as a womb, as the place where they come from, and also as the place where they go after the death. Their hunting is not merely a foodprocuring activities, but also the process through which they confirm the continuity with the forest world. Such a life deeply incorporated into the forest ecosystem and the view of nature deriving from it show a marked contrast with the Western idea of the forest, which is based on dualistic opposition between man and nature.

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The Satawalese (Central Caroline Islands, Micronesia) conceptualization on the nature is described with special reference to the division of time, folk-orientation, folk-taxonomy, and taboo observances. Sidereal, lunar, and celestial movements and natural phenomenon such as the wind direction, precipitation, riping of breadfuit, and fish run are combined together to make the timereckoning and folk-orientation system of the island. Folk-taxonomy of marine life and the associated food observances as metaphors well reflect the maritime tradition of the people in which profound knowledge and marine lore are accumulated. Individual sets of these folk knowledge are examined as the hypothesized tripolar and circulation models. Land and sea are regarded as being opposed each other in terms of odour of the two areas but both regimes are neutral to the heavenly world. Odours related to human sex and female blood are also avoided by the supernatural beings controlling the land and the sea. These three domains figure a tripolar model of odour. Pwuupw has three meanings: triggerfish (Balistidae), the southern Cross (Crux) and the space allocation in the navigational knowledge of Pwuupwunapanap. The polysemic use of pwuupw suggests the integrated conception of nature as a circulation model between the sea and the heaven. The study of indigenous knowledge and cultural construction on the nature is also essential to an understanding about on-going degradation processes of the environment.

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The Munda people, who lives in the Chotanagpur plateau in eastern India, is a ricecultivator. This paper is to investigate the Munda’s view on Nature.
I begin to discuss the concept of soul in Mundari, which is very complicated. In the correspondence to the word ‘soul’ in English, we have four words; e.g. ji, roa, raisi, wnbul. The words roa and raisi are used only for humanbeings, domesticated animals; i.e., cows and goats, and main crops; i.e., rices and finger millets. Further, I found the paratlelism between human’s or ancestoral soul and rice’s soul in the myths and rituals. This is an important idea to understand the Munda’s view on Nafire.
Moreover, the Munda people prays God for successful rice cultivation in the agrarian rituds. These ue singbonga (Sun God), buru bonga (Mountain God) and ikir bonga (River God). All is belonging to the nature. It means that the rice-ancestor-nature complex can be found in the Munda microcosmos.
ln conclusion it seems to me that the Munda culture also contains a typical feature of pan-Asian rice culture. We need a comparative study on Asian rice culture in this respect.

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