In the forested mountainous region of northern Thailand, traditional tea cultivation lands—called the ‘miang tea gardens’—have been maintained for the production of chewing tea called ‘miang’. These miang tea gardens consist of tea trees that are covered by tall shade trees and small patches of forest. Therefore, the miang tea gardens have been recognised as an agroforestry system. The long-term changes in the population and land use patterns in the miang producing villages (miang villages) have not yet been identified, particularly during the last three decades, when Thailand experienced drastic socioeconomic changes.
This study attempts to elucidate the dynamics of one of the miang village, specifically, the P community in PMO village in Chiang Mai Province. Applied methodologies include conducting direct interviews with the villagers, mapping of the gardens using global positioning system (GPS) and an analysis with geographical information systems (GIS). This paper discusses the population and land use developments that took place in this village and its socioeconomic factors.
We classified the village history into the following two phases: the ‘expansion phase’ and the ‘declining phase’. The former extended from 1970 to the early 1980s, and the latter spanned the late 1980s to 2002. During the expansion phase, the population of the P community increased with the prospect of an increase in the production of miang both inside and outside the village. The miang farmers began converting mature forests into the miang tea gardens. Contrary to this trend, during the declining phase, the population of the P community declined due to the migration of the working population to other industries, following a recession in the miang market. During this phase, the management of the miang tea gardens coped with the abovementioned socioeconomic developments surrounding the production of miang. In order to diversify the utilisation of land, the management adopted strategies—such as converting the production of miang into drinking tea production, cultivating fruit and coffee trees, grazing cattle and accepting ecotourism.

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This research presents indigenous knowledge of the Baduy community in using and managing natural resources in their homeland. The Baduy community lives in a special reserve of sacred forestland (in state forest) with an area of 5,101.85 ha in Banten Province, Java Island, Indonesia. They have indigenous knowledge of how to live in harmony with nature. To sustain their traditional customs, the Baduy people have been implementing a strict code of conduct and taboos guided by their traditional government. They classify their land into five categories as follows: huma, kebon, reuma, leuweung kolot, and leuweung titipan. They also arrange specific terms for a traditional tenure system. Swidden farming is the main pillar of their livelihood and they follow sequential activities on their swidden farming based on a traditional calendar. Due to the taboos imposed by their ancestors against using many products from outside, the Baduy people have been producing their livelihood products for a long time. They use raw materials extracted from the forest area which is rich in natural resources. With increasing contact with outside communities, as well as a high demand of cash income, the Baduy people sell some of their products to outsiders. Similar to many other indigenous people around the world, the Baduy people today live with a dual economy of subsistence and cash income.

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This study observes the characteristics of private forest (PF) in Sumberejo village and the role played by PF on farm household and village economy. Economic base techniques including location quotient (LQ), surplus of income, and multiplier effect (M_e) were applied. PF in Sumberejo were developed by farmers with timber trees species, mainly teak and mahogany which were planted on three forms of the silvicultural system, i.e. monoculture, polyculture, and agroforestry. The farmers managed PF on their own habit to determine such constraints concerning their land and to respond a high demand of timber in Java. Many buyers involved in timber market in Sumberejo created a variety of marketing channels which give farmers to choice the convenience's buyers. Even though, PF has not contributed a big portion to the total household income, but it was important as saving asset. Economic base analysis confirmed that PF is a basic sector of the economy in Sumberejo and created surplus of income for that village. Further analysis proved that PF has the biggest M_e value. This indicated that PF is “prime mover role” sector and therefore it can be promoted as “engine” for economic development of that village.

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A study on nutrient cycling and nutrient balances at different scales in the autonomous region of Guangxi was carried out. Using data from a survey in representative cropping systems in different counties and nutrient input: output calculations based on published data, the agricultural statistics revealed a detailed knowledge about the nutrient inputs from organic and inorganic resources to the main cropping systems on lowland and upland. The overall consumption of N and K was not sufficient to cover the demand of the crops whereas the P balance showed a positive value. In lowlands, N inputs clearly exceeded outputs whereas on the uplands the balance of N was negative, leading to overall negative balance for nitrogen. Substantially more potash fertilizer is required to overcome the negative balance and the severe K deficit observed. The prediction for future mineral fertilizer consumption indicates 7-10%annual increase to meet the growing demand and to establish balanced nutrient budgets in the farmlands.

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Water chemistry of two rivers in Central Kalimantan, Indonesia was surveyed in September 2003. Effects from sea salt on the surface water chemistry of the river appeared 94 km upstream from the mouth of the Sebangau River, although little effect from sea salt appeared 45 km upstream from the mouth of the Kahayan River. Water discharged from canals (Paduran, Pangkoh and Pulangpisau) into the mainstream of the Sebangau River and the Kahayan River showed lower pH compared to the mainstream water of the rivers, implying sulfuric acid loading from the canal to the mainstream of the rivers. The ratio of SO₄^2-/Cl^-, which was used as a parameter for estimating the contribution of pyritic sulfate to the river water chemistry, showed that the sulfuric acid loading from pyrite oxidation appeared from the river mouth up to 145-179 km upstream in both the rivers.

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Peat samples from a 3.60 m core collected from Rawa Danau, West Java, Indonesia, were studied to reconstruct past vegetation and climate changes. The study carried out combining visual observations, elemental analyses, stable carbon and nitrogen isotope analyses as well as CuO oxidation of lignin residues. Variations of total organic carbon (TOC: 55.53-3.18 %, mean 23.31 %), total nitrogen (TN: 2.52-0.06 %, mean 0.94 %) and water content (WC: 46.8-93.2 %, mean 79.0 %) with core lithology reflected dry and wet cycles. Vertical profiles for TOC, TN, WC and core lithology also had signatures of heavy precipitations and consequent land sliding at the abrupt change of climate (wet cycles). Variations of (C/N)_a (15-93, mean 27) and δ¹³C (-27.0 to -30.1 ‰, mean -28.5 ‰) of organic matter (OM) in the peat core indicated that the organic material was comprised of terrestrial C3 plant material. The direct input of aquatic plant matter was small or overwhelmed by high terrestrial input, although changes in lake productivity due to decreasing/increasing nutrient availability were reflected in δ¹⁵N profile. At low elevations in the tropical area, a large shift in vegetation zones was not likely observed. Most species might persist at the site when small-scale localized environmental changes and human disturbances or natural forest fires occurred, but the abundances of particular species might change, depending on the natural conditions in which a species could grow. However, vegetation changes associated with periodical sequence of dry and wet microenvironment were inferred from the total lignin phenol (TLP) profile.

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Twenty-one taxa in 4 genera (Calophyllum, Mammea, Mesua s.l. and Garcinia) of Guttiferae from several areas in Peninsular Malaysia were used to investigate the status and relationships of taxa within the family Guttiferae using the chloroplast DNA trnL-trnF sequence data. Molecular phylogeny results indicated that Calophyllum, Mammea and Garcinia are monophyletic genera. However, the genus Mesua appeared to be polyphyletic as Mesua ferrea did not form a cluster with the other Mesua taxa. Therefore, the molecular phylogeny supports the morphological classification that Mesua taxa in Peninsular Malaysia other than M. ferrea, be transferred back into genus Kayea. On the other hand, the molecular phylogeny disagrees with the morphological classification of Calophyllum wallichianum var. wallichianum and C. wallichianum var. incrassatum as varieties of C. wallichianum. Therefore, the status of these two varieties should be reinstated to distinct species as C. wallichianum and C. incrassatum respectively.

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We observed spatial and topographic patterns of canopy gap formation in a mixed dipterocarp forest over 4 years (1993-1996) (new gaps) and before 1993 (old gaps) in a 24-ha plot in Sarawak, Malaysia. Results showed a much lower canopy gap-formation rate (0.63 gaps ha^-1; mean gap area: 49.4 m² ha^-1, gap formation ratio: 0.067% year^-1 for ≤2-m gaps) than the range reported for tropical forests in the Neotropics. The spatial aggregation of new canopy gaps and old large-scale gaps on steep back slopes suggests that canopy gaps are closely linked to topography, especially to landslides. Uprooted trees were concentrated on steeper and more concave slopes and at more intermediate elevations than expected by chance, and occasionally caused landslides. Broken trees, including standing dead trees, were distributed at higher altitudes and on more convex slopes than uprooted trees. A variety of species-specific modes of gap makers between the two types of treefall suggest a degree of predictability in the type of treefall that will be present at different topographic positions. The marked differences in frequency distributions of area ratios of ≤2-m gaps to ≤5-m gaps within each gap showed temporal and spatial heterogeneity of vegetation recovery between new and old gaps. Thus, a forest with low gap-formation rates and abundant and nonrandom distribution of small-scale disturbances suggests spatial heterogeneity of vegetation recovery and contributes to a variable distribution of habitat specialists in canopy gaps.

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A comparison of tree architectures and allometries between two congeneric, light-demanding species, Pterospermum diversifolium and P. javanicum (Sterculiaceae), revealed that P. diversifolium is favored over P. javanicum at high light levels, but that the opposite is true at low light levels. Therefore, the abundance of these species within a landscape is likely to depend largely on habitat heterogeneities in understory light conditions. To verify this prediction, we compared the abundances and population size structures of these species among three 1-ha plots established on a ridge, a slope, and a flat plain within a tropical floodplain forest in East Kalimantan, Indonesia. We found a significant difference in understory light conditions among the plots: ridge > slope = flat plain. The abundances and size distributions of P. javanicum within the plots indicate that this species has a wide habitat range in the study area, from flat plains to slopes and ridges. We found no P. diversifolium in the flat plot; the habitat of this species may thus be restricted to ridges and slopes. Differences in the population size structures between the ridge and slope plots suggest that P. diversifolium regenerates more abundantly on ridges than on slopes. We discuss differences among plots in the abundance and size structure of P. diversifolium from the viewpoints of habitat heterogeneities in terms of differences in understory light and soil water conditions.

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The early stages of vegetation recovery were studied on a degraded lowland peat-swamp in Narathiwat Province, southeastern Thailand. Vegetation censuses were carried out nine times over a six-year period following a severe fire. 50 1m² quadrats (15 for the first census) were established, and the phytosociological vegetation profile for each quadrat was surveyed each year. Also, the population structure of Melaleuca cajuputi Powell (density, maximum height and maturity) was investigated. The results showed that vegetation height and coverage expanded rapidly, but the total number of species increased slowly. M. cajuputi seedlings emerged about three months after the seed rain that occurred at the time of the fire. By a year and a half later these trees had built up a dense canopy and started sexual reproduction. These results show that vegetation recovery was induced primarily by the vigorous growth of the M. cajuputi population in the study site.

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Tropical secondary forests own enormous potential and ecological function due to their vast area, and are an increasingly important component of the forest resources in the tropics. This paper reviews main research outcomes of secondary forests during their succession process. Soil-stored seeds significantly contribute to the development of secondary forests, increased levels of incident light temperature stimulate seed germination, whereas remnant vegetation and seed predator have strongly negative influence on the rate of initial colonization. Species and number of secondary forests generally increase with succession process. Early successional species are generally shade-intolerant while late successional species are shade-tolerant. The time frame that plant species richness in secondary forests approach old-growth forests varies considerably depending on forest type, type and intensity of past land use, and environmental conditions. Plantation can accelerate germination and growth of seeds by improving the light, temperature and the degree of humidity of soil surface layer, so that they greatly accelerate the processes of plant succession. Most herbivores feed in secondary forests because pioneer species in secondary forests do have little or no mechanical or chemical protection against herbivores and many early and late serial tree species in secondary forests produce edible fruits in large quantities. Environment and fire have some effects on secondary forest succession. In early succession, relatively more biomass is allocated to resource acquiring tissues (leaves and fine roots) and in later stages more is allocated towards structural materials (woody stems and coarse roots). The nutrient cycling of secondary forests is quick during approximately the first 15 years of succession and it decreases as forests age. The losses of soil organic matter and N due to deforestation and burning decreases soil fertility of secondary forests.

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