Phenological changes in leaf production, leaf fall and inflorescence production of an understory palm, Pinanga coronata (Arecaceae), in a tropical montane rainforest on Mount Halimun, Westjava, Indonesia, were observed monthly for a period of 17 months (November 1998 to March 2000). Meteorological data indicated that there were yearly dry (June to September) and wet seasons (October to May), and that the air temperature varied little through the year. Leaf turnover rate (average leaf production and fall rates) decreased during the dry period. However inflorescence production was continuous rather than seasonal. The number of leaves in a crown was nearly constant throughout the study period. Adult shoots that produced more leaves produced more inflorescences. Leaf production rate of P. coronata is sensitive to water availability. Therefore, water is one of the significant resources for growth of P. coronata.

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Soil biodiversity may relate to environmental changes in the soil. To determine how soil environmental factors relate to soil bacterial diversity, we compared culturable bacterial communities in soils under bare ground (BG, highly degraded), dry dipterocarp forest (DDF, moderately disturbed) and dry evergreen forest (DEF, the original vegetation) that form a degradation gradient in the Sakaerat Environmental Research Station (SERS), Thailand. The Shannon diversity and evenness and Simpson indexes were determined using the sole carbon source most probable number method. Variation patterns of these indexes were analyzed for three data sets obtained during the dry (February) to wet aune) seasonal transition. Only the March data set had significant differences in the diversity indexes among the vegetative types. In March, BG soil had a significantly lower Shannon diversity index (1.77) and evenness index (0.64) than the others (2.34 and 0.84 for DDF and 2.41 and 0.87 for DEF), and a higher Simpson index of 0.23 (0.08 for DDF and 0.07 for DEF). Repeated measures analysis of variance at p=0.05 indicated that both vegetative type and sampling time were significant sources of variation of the Shannon indexes, while only sampling time was a significant source of variation of the Simpson index. Simple and multiple regression analyses and a redundancy analysis ordination diagram showed that throughout the period of the study, soil water content was the most significant soil environmental factor with regard to the Shannon and Simpson diversity indexes. The soil bacterial communities under all the vegetative types had higher diversity and evenness in the wet months. The transition from dry to wet season had a grater effect on variation of the diversity indexes than did the soil degradation gradient.

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This paper examines livelihood diversity and flexibility in a village located near Miri, Sarawak, Malaysia. At present, a single typical livelihood of the Iban or an Iban village no longer exists, because the Iban easily adapted their livelihood in accordance with the local socio-economic changes. Even within a village, there are occupational options and periodic changes for each household. Studies on the Iban:zs livelihood have so far focused on the individual household (bilek farnily) unit This paper extends those analyses to stress the importance of the functions of household members, with respect to the conditions of labor, such as a number of household members capable of working and their ages and sex, character and work and activity preference, and individual skills. Individual members who have different characteristics and abilities contribute to a diverse and flexible way of livelihood characteristic of the Iban.
In this study, it is found that the present livelihood and the periodic livelihood changes were brought about through the activities of individual members of households. Presently, in the village studied, various kinds of livelihood activities are practiced, including: planting wet paddy, pepper cultivation, rattan basketry, logging, and waged work outside the village. Preference for these activities by each household is different. Some households engage in all of the above-mentioned activities, while others only work for a wage. Waged work outside the village seems important, but some households make a living without it. Periodic changes in livelihood relate to changes in socio-economic conditions. Major changes occurred before the 19405 (the main activities were hill and wet paddy cultivation and wild rubber tapping), from the 1950s to the 1970s (main occupations were wet paddy cultivation and Para rubber tapping), and after the mid-l980s (various kinds of activities as mentioned above).

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Thirteen mineral element concentrations in leaf samples of 478 native plants growing in peat swamps and heath forests of Central Kalimantan were detemined. Chemical properties of surface soils in the study sites were also determined. In all sampling sites the mean concentrations of essential macro-elements were variable than that of micro-elements. The chemical properties of surface soils necessitate that the peat podzolic soils are nutrient-limited. However, some native plants growing on these soils show a preference to accumulate excessive concentrations of particular micro-elements, such as Na, Mn, Al, and Si, in their leaves. The results of this study confirm that the concentrations of elements in plant leaves appear to be indicative of site variation and are the result of environmental adaptation. AI, Si, and Na were the principal elements determining the nutritional characteristics of the native plant leaves. However, only AI has clear inter-element relationships for each plant group. Therefore, the relationships between AI-Na and Al-Si in leaves reveal important strategies of plant adaptation to the nutrient-poor ecosystems of peat swamps and heath forests. Native plants belonging to the Eurosid I evolutionary group had very high AI concentrations in their leaves, both in Lahei and Kalampangan peat swamp forests. Combre/ocarpus rotunda/us (Anisophylleaceae family) was predominant in the study sites and, could be regarded as an AI accumulating species (leaf AI concentration within the range of 2,000 - 10,000 mg kg^-I). AI-accumulating species likely restrict the accumulation of other mineral elements in their leaves, whereas non AI-accumulating species tend to accumulate other mineral elements in their leaves. Although the mechanism for this eco-physiological adaptation remains unclear, it is suspected that AI-accumulating species (c.f. C. rotunda/us) have developed efficient strategies enabling them to utilize low amounts of essential elements in order to be able to grow in a nutrient-limited environment. Information gathered about AI-accumulation by certain wild plants will useful in selecting appropriate species to rehabilitate damaged peat swamp and heath forests.

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