Tamaraw (Bubalus mindorensis) is a wild water buffalo endemic to the island of Mindoro, Philippines. It is one of the world’s critically endangered species, and only three mountainous areas have confirmed tamaraw populations. One of the habitats, Mt. Aruyan, is inhabited by hundreds number of indigenous peoples (Mangyan) who live in clusters of villages. To understand the present status of the tamaraw in Mt. Aruyan, especially human-tamaraw conflicts, we conducted a field survey by camera trap, route censuses, and interviews with the Mangyan. One adult male was identified by camera trap and some individuals were identified by signs. Tamaraw habitat and the domiciles of the Mangyan completely overlap, and slash-and-burn farming by the Mangyan has significantly reduced tamaraw habitat. Moreover, outsiders poaching with guns directly contributed to the decline of tamaraw population. These results indicate that the conservation of tamaraw in the Mt. Aruyan habitat is extremely difficult. Therefore, conservation in other habitats is considered a higher priority.

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Ecological characteristics such as planted crops and soil fertility were studied in 60 home gardens in Phrae province, northern Thailand. The studied home gardens were 2 to 70 years old, and were mostly 400 to 600 m², which is small compared with those reported in previous studies of tropical and subtropical regions. In all, 275 species were recorded, of which 45% were tree species, followed by shrub (25%), herb (18%), and climber species (12%). The most common use of the plants was as food (27%), followed by ornamentation (24%), medicine (15%), building materials (14%), and fruit (12%). In many gardens, the numbers of species were 0.05 to 0.1 per square meter and 25 to 40 per garden. The Simpson and the Shannon-Wiener indices respectively exceeded 0.9 and 3.0. Cocos nucifera dominated the higher stratum of 10 m or higher. Although basal areas of tree species were typically less than 20 cm² m^-2, 12 home gardens showed basal areas exceeding this value. Actually, 437 trees (64 species) had a larger DBH than 20 cm, sometimes larger than 50 cm. Most these trees comprised only four species: C. nucifera (21%), Tamarindus indica (15%), Artocarpus heterophyllus (11%), and Mangifera indica (10%). Results reveal that species diversity of the home garden in this study was higher, especially in terms of unit area, than species diversity in other tropical regions, and higher than reported values of a mixed deciduous forest and teak plantations in northern Thailand. Most soils in the home gardens showed sandy clay loam to light clay texture. Both surface and subsurface soils were less acidic and rich in nutrient contents, irrespective of the fertilizer type (chemical, organic, and no fertilizer application). The cation exchange sites of the soils were saturated with exchangeable bases, predominated by Ca. Consequently, the levels of base saturation were greater than 100%. In comparison with other land uses in northern Thailand, the home gardens had characteristically high contents of nutrients throughout the soil profile.

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Soil fertility status under various types of upland farming was evaluated in a village in Mae Taeng District of Chiang Mai Province in northern Thailand. The farmlands were on sloping land in a transitional zone of hill evergreen and mixed deciduous forests (800-1000 m a.s.l.). Miang tea (Camellia sinensis var. assamica), traditionally cultivated as the sole main cash crop, has been replaced by other cash crops. The studied soils originated from granite (n=30), limestone (n=16), and shale (n=6). Clay minerals were composed mainly of kaolin minerals in the granite soils and quartz, chlorite, gibbsite, mica, and kaolin minerals in the limestone and shale soils. Soil texture classes differed among soil types. However, granite and shale soils showed similar chemical properties to each other with an acidic nature and lower levels of exchangeable bases. Irrespective of the parent material, the CEC values were correlated with soil organic matter contents but not with clay contents. The levels of soil organic matter and the resulting CEC as well as ECEC values were higher in the limestone soils than in the granite and shale soils. These results suggest that higher negative charges in the limestone soils were derived from soil organic matter and that these charges developed under higher soil pH conditions. The C/N ratios of the limestone soils were lower than those in the granite soils and shale soils, reflecting the well-decomposed status of soil organic matter. The granite soils were classified into three groups based on their physicochemical properties: forest-type soils (remnant forest, secondary forest, miang tea garden and lychee orchard), soils of annual crop fields, and soils of the home gardens. The forest-type soils were characterized by their strong acidic nature with lower contents of exchangeable bases and available P. Soils of the annual crop fields and those of home gardens showed a less acidic nature and nutrient accumulation occurring as a result of fertilizer application. However, a difference between these soils was that while the annual crop fields possessed preferable soil physical properties for crops caused by tillage management, soils of home gardens were subjected to compaction throughout soil profiles. In contrast to granite soils, the effects of different land uses on soil fertility were not evident in limestone soils. However, the annual crop fields and orange orchards had low total C and total N, engendering lower CEC values. Although the available P of these soils was high because of fertilizer application, fertilizer N in the annual crop fields seemed not to contribute to a buildup of total N and ammonium N. Both in lychee orchards with the granite soils and orange orchards with limestone soils, fertilizer P had accumulated around trees where fertilizer was usually applied. For shale soils, the subsurface soils under the oolong tea gardens (Camellia sinensis var. sinensis) were rich in total C and N and less compacted than soils of other land uses. Results show that different farming practices affected soil fertility status depending on soil types with different parent materials.

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We investigated the diversification and diversity in waxy rice cultivars (Oryza sativa L.) in Laos, using three complementary DNA marker systems. We documented three variable DNA markers, including a SSR locus RM190 (number of CT-motif repeat), G-T substitution, and 23 bp duplication. These were analyzed in 389 strains that were collected from northern and central Laos. Variation in cpDNA, presence of absence of a 69 bp deletion at the ORF100, was used for a background classification of all strains as indica or japonica. The three nuclear polymorphisms was all variation within waxy locus. In the RM190 region, nine alleles with different numbers of CT repeats (n=10, 11, 12, 16, 17, 18, 19, 20 and 22) were detected in non-waxy (Wx) alleles, while seven of them (n=12, 16, 17, 18, 19, 20 and 22) were found in waxy (wx) alleles. Compared to previous studies, more allele types were found in northern and central Laos than in neighboring countries. It is considered that the genetic diversity of rice landraces is high in northern and central Laos, and it may be because the high cultural diversity and diverse agricultural systems that persist there. The distribution of landraces with each CT allele type showed neither ethnic bias nor geographical bias. This suggests that there has been frequent exchange of landraces beyond political-borders and between ethnic groups in northern Laos.

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We made litter fall observations in a West Sumatran tropical rain forest every 2 weeks through 3 years (including the drought year, 1997). Seasonal changes in long-term average rainfall were bimodal, but even in the two dry seasons average monthly precipitation was > 200 mm. Leaf-fall rates in a year with normal rainfall peaked in the first dry season; leaves made up one-third of mean annual litter fall. Larger trees had highly synchronized leaf fall during the peak shedding period. Smaller trees shed simultaneously during severe drought. Twigs < 0.5 cm diameter tended to fall in proportion to the 3/2 power of leaf-fall rates; therefore, we considered autonomous twig fall in relation to the pipe model theory. Variances in reproductive organ shedding rates (seasonal and annual) were larger than those of leaves and branches, possibly because of the higher susceptibility of reproductive parts to drought. Reproductive fall rates in the year with normal weather peaked in May (flowers) and August (fruits). Seasonal patterns of flowering and fruiting were classified into three groups. Understory species had an “extended flowering” pattern. We discuss phenological patterns found in this very high humidity climate and the impacts of increasingly frequent droughts.

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Information on the dispersal distance achieved by disturbance-tolerant frugivores is critical for predicting the possibility of plant population persistence and the speed of vegetation recovery in degraded forests. We estimated the dispersal kernel of one large-seeded plant with ‘primate fruits’ rambutans (Nephelium lappaceum), generated by common palm civets (Paradoxurus hermaphroditus) in the degraded forest in the Tabin Wildlife Reserve, Sabah, Malaysia. We predicted that for the dispersal distance, civets are superior to macaques, which are another potential disperser for large-seeded ‘primates fruit’ in degraded forests. Observations on feeding trials showed that the civets often swallowed seeds, but both the macaques never did. Thus the mean seed retention times of the civets, 2.6 h, were much longer than those of macaques: 75 seconds for the long-tailed macaques and 156 seconds for the pig-tailed macaques. Radio tracking the activity of the common palm civets (4 males and 3 females) demonstrated that they traveled several hundreds of meters during gut passage time. The estimated mean dispersal distance was 216 m. Male dispersed the seeds in significantly longer distance (270 m) than female (156 m), reflecting the difference in home range size between sexes. These results indicated that common palm civets play an important role in the dispersal of large-seeded plants as long-distance dispersers, probably surpassing macaques.

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A survey of the number of fallen acorns from trees of three species in the beech family (Fagaceae; Lithocarpus edulis, Castanopsis sieboldii, Quercus miyagii) and the insects that eat these acorns was conducted on subtropical Okinawa Island between 2000 and 2005. The largest number of L. edulis acorns fell in 2001, whereas only a few acorns fell in 2005, and there was little annual variation in the other years. The acorn production of C. sieboldii was repeatedly synchronized and abundant, with large numbers of fallen acorns in 2000 and 2003. Although Q. miyagii produced large numbers of fallen acorns in 2000 and 2005, none were collected in 2002 and 2004. The years of maximum production of mature fallen acorns did not coincide among the three species during the 6-year study period. Eleven species of acorn-infesting insects were confirmed: five coleopterans, three lepidopterans, two hymenopterans, and one dipteran. Curculio hilgendorfi, Poecilips cardamomi, P. graniceps, and P. variabilis damaged acorns of all three tree species, whereas P. advena damaged only C. sieboldii and Q. miyagii acorns. Neoblastobasis biceratala damaged C. sieboldii and Q. miyagii acorns, but Camptomastyx sp. and Tortricidae (Olethreutinae) sp. damaged only those of C. sieboldii. Cynipidae sp. 1 damaged L. edulis and Cynipidae sp. 2 damaged Q. miyagii, whereas Tipulidae sp. damaged L. edulis and Q. miyagii. This study is the first to document the presence of P. cardamomi, P. graniceps, P. variabilis, and N. biceratala on Okinawa Island. Additionally, there are more species in the post-dispersal acorn-feeding guild (PAF guild) than in the mature acorn-feeding guild (MAF guild), and it is inferred that this guild difference represents a difference between subtropical Okinawa Island and the temperate zone.

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