Understanding the regrowth condition and pattern for the vine plant Epipremnum aureum is important for effective removal of this invasive species. The purpose of this study was to clarify the influence of the light environment, size of the plant body, and existence of roots on the survival and regrowth of a piece of the plant body of E. aureum. We surveyed the survival and regrowth of E. aureum for plant cuttings of different sizes under three light conditions representing the outside, edge, and inside of forests (Experiment 1), and for plant cuttings of different sizes with or without roots inside forests (Experiment 2). In Experiment 1, we observed a high mortality outside forests, but confirmed higher survival rate and probability of regrowth at forest edges and inside forests. Even one leaf with a stem and root could regrow under low light intensity, whereas the amount of regrown plant organs or tissue was higher for a larger cutting. In Experiment 2, the number of roots increased more rapidly for plant cuttings without initial roots than for those with initial roots, although the amount of regrown plant tissue increased with increasing cutting size. Even small pieces of the plant body of E. aureum with no roots frequently survived and regrew under low light intensity. This indicates that small pieces of the plant body should not be left at forest edges or inside forests during removal work.

The knowledge of xylem maturation manner is importance to foresters and wood processors as it has major implications for end-product quality. This study aims to evaluate the maturation manner of secondary xylem in Eucalyptus camaldulensis for solid wood production. The samples were 45 twelve-year-old trees from 15 families with different radial growth in a progeny test site for the E. camaldulensis second generation in Thailand. Two mixed-effect models (cambial-age dependency and diameter-growth dependency models) were developed for radial variation of wood properties, resulting in that the cambial-age dependency model was a good fitting for all wood properties rather than growth-diameter models, with a few exceptions. Therefore, the secondary xylem of this species matures depending on cambial age rather than diameter growth. Changing ratios of multiple wood properties at 1-year intervals estimated by the cambial-age dependency model became stable after a cambial age of 11.8 years. The wood formed after starting xylem maturation showed 1) longer wood fiber length, 2) smaller number and larger diameter of vessels, 3) larger diameter and thicker wall thickness of wood fiber, and 4) higher density and compressive strength, rather than those formed in the early growth stage. Based on the results, desirable wood properties for solid wood products can be obtained by prolonging the rotation period from the present short rotation periods.

The foraging and feeding behaviors were observed for the myrmicine ant Calyptomyrmex rectopilosus collected in northern Vietnam. C. rectopilosus was found to be a specialized predator on the arthropod eggs, and the queen fed on trophic eggs and engaged in oral trophallaxis with workers. Unlike Calyptomyrmex nitidiusculus sp. nov. [referred to as Calyptomyrmex sp. in the paper by Ito (2001)] observed in Bogor, West Java, Indonesia, workers of C. rectopilosus never showed larval hemolymph feeding. The behavioral response to cricket eggs was also observed for 13 omnivorous and/or predatory ants, and compared with that of C. rectopilosus. Calyptomyrmex nitidiusculus sp. nov., is described based on the worker, queen and male collected in the Bogor Botanical Gardens, West Java, Indonesia.

Oil palms are extensively planted in tropical countries and causing a severe decline in biodiversity. Alley-cropping is an agroforestry practice that has been proven to sustain greater diversity of terrestrial arthropods than monoculture plantations. However, the environmental factors responsible for these differences remain unclear. This study aimed to identify the environmental factors influencing terrestrial arthropod abundance and richness in alley-cropping and monoculture oil palm plantations. We sampled terrestrial arthropod using 840 pitfall traps under seven treatments: oil palm alley-cropping systems with Bactris, bamboo, black pepper, cacao, and pineapple; and two oil palm monoculture systems. We assessed the microenvironment (presence/absence of alley cropping, vegetation coverage, soil surface temperature, soil moisture, light intensity, and relative air humidity) at each sampling site. Overall, 14,358 arthropods belonging to 19 orders were collected. The presence of alley-cropping was the only factor that positively affected the arthropod abundance and order richness. Arthropod abundance was negatively affected by soil moisture, suggesting that the dominant species, even in alley-cropping, were generalist species acclimated to dry soil conditions. Our study suggests that alley-cropping in oil palm plantations could increase the terrestrial arthropods diversity by increasing the diversity of vegetation (even with only one additional crop), rather than improving habitat microclimate. However, as microclimate remained intense, alley-cropping with only one secondary crop in our study site would not be sufficient to conserve forest specialist species. We suggest that producers of oil palm pay close attention to the potential of alley-cropping incorporating multiple secondary crops to increase biodiversity in plantations.

To understand the biomass and floristics of secondary forests in Borneo better, we established a one-hectare plot on the lower slopes of Gunung Kelam in West Kalimantan, Indonesia. We recorded 683 stems (≥5 cm dbh) representing 50 species, 44 genera and 27 families; the five species with the greatest Importance Value were Artocarpus elasticus (IV＝81.5), Vitex pinnata (40.2), Cryptocarya ferrea (14.2), Polyscias elliptica (12.7) and Gordonia excelsa (10.7); stem dbh distributions differed among species indicating that succession was still occurring. The stand basal area was 29.0 m². We estimated biomass with eight different allometric equations. Four equations (Chave, Hashimoto, Kenzo and Manuri-DGH9) showed very close agreement at around 137 Mg ha^－1 suggesting they were all suitable for mid-aged secondary forest biomass estimation in this region. Despite tree diversity and biomass being lower than nearby primary forest, secondary forests will become increasingly prevalent in the future and this therefore necessitates their increased study and conservation.

For many years, there has been a prevailing belief that the activity of soil microorganisms in tropical forests is limited by the availability of phosphorus (P). This belief has traditionally found support in experimental research, consistently demonstrating that the addition of P leads to an increase in heterotrophic soil respiration. However, we have introduced an alternative hypothesis that challenges this conventional perspective. Our proposition suggests that the evidence traditionally utilized to substantiate this belief is, in fact, an outcome of increased carbon (C) availability resulting from abiotic processes initiated by the release of organic matter from soil mineral surfaces, which occurs as a consequence of P addition. Indeed, our previous study has empirically established two significant findings: (i) the acceleration of soil respiration through P fertilization, accompanied by the absence of concurrent stimulation in litter decomposition, and (ii) the immediate increase in extracted DOC resulting from the laboratory introduction of P prior to extraction. In the present study, we have expanded upon the existing body of evidence by providing field-based support that soils subjected to P fertilization display a reduced ability to adsorb newly introduced DOC. The prolonged period of 9 years of continuous fertilization tended to diminish the adsorption capacity of experimentally added DOC, which probably facilitated the acquisition of C by soil microorganisms and thus contributed to the stimulation of soil respiration in our study site. Building upon our previous findings, we propose that the traditionally used evidence to substantiate microbial P limitation is, in fact, a consequence of abiotically increased C availability resulting from P addition.