Summary 1.Termites are major decomposers in tropical regions and play an important role in soil processes. This study measured the impact of land-use intensification on the termite assemblage of lowland rain forest in Jambi Province, on the Indonesian island of Sumatra. Termite composition was assessed in seven land-use types along a disturbance gradient, from primary forest, through different silvicultural systems, to grassland and cultivated land without trees. A range of environmental variables was also measured. 2. Termite species richness and relative abundance declined as follows: primary forest > selectively logged forest > mature 'jungle rubber' (a diverse agro-forest dominated by rubber trees) > mature rubber plantation > young Paraserianthes falcataria plantation (a softwood tree) > Imperata cylindrica grassland > cassava garden. Termite richness fell from 34 species in the primary forest to one species in the cassava garden. The relative abundance of soil-feeding termites showed a significantly greater decline along the gradient than did wood-feeding termites. 3. Of the environmental variables, woody plant basal area was most strongly correlated with termite species richness ( r = 0·973) and relative abundance ( r = 0·980). This reflects the response of forest-adapted termites to progressive simplification of the physical structure of the habitat, resulting in the reduction of canopy cover and alteration in microclimate, and the loss of feeding and nesting sites. 4. Synthesis and applications . Comparisons with other studies show that the decline in termite species richness and relative abundance seen at Jambi is a general trend that occurs elsewhere when forests are converted to other land uses. To help mitigate the loss of termites when forests are disturbed, we recommend the following management practices: the use of reduced-impact logging techniques, maximizing forest patch size and connectivity, minimizing length of forest edges, and leaving dead wood to decay in situ .

Plant and bird diversity in the Indonesian jungle rubber agroforestry system was compared to that in primary forest and rubber plantations by integrating new and existing data from a lowland rain forest area in Sumatra. Jungle rubber gardens are low-input rubber (Hevea brasiliensis) agroforests that structurally resemble secondary forest and in which wild species are tolerated by the farmer. As primary forests have almost completely disappeared from the lowlands of the Sumatra peneplain, our aim was to assess the contribution of jungle rubber as a land use type to the conservation of plant and bird species, especially those that are associated with the forest interior of primary and old secondary forest. Speciesaccumulation curves were compiled for terrestrial and epiphytic pteridophytes, trees and birds, and for subsets of 'forest species' of terrestrial pteridophytes and birds. Comparing jungle rubber and primary forest, groups differed in relative species richness patterns. Species richness in jungle rubber was slightly higher (terrestrial pteridophytes), similar (birds) or lower (epiphytic pteridophytes, trees, vascular plants as a whole) than in primary forest. For subsets of 'forest species' of terrestrial pteridophytes and birds, species richness in jungle rubber was lower than in primary forest. For all groups, species richness in jungle rubber was generally higher than in rubber plantations. Although species conservation in jungle rubber is limited by management practices and by a slash-and-burn cycle for replanting of about 40 years, this forest-like land use does support species diversity in an impoverished landscape increasingly dominated by monoculture plantations.

Although Gyrinops versteegii has been domesticated by local community in Sragen Regency, the environmental factor and species which high compatibility with G. versteegii still not know yet. The objectives of this s have have n research were 1) o know which one of those vegetation communities that gives the best the diameter and height t growth of the domesticated G. versteegii 2) to know the environmental factors that influenced the growth of the , and diameter and height of the domesticated G. versteegii. Sampling was done systematically with a plot of size 20 20m × for trees, 10 10m for poles, and 5 5m for saplings with a total of 28 plots. SPSS Program version 22 was used for × × cluster, one-way anova, correlation, and multiple regression analysis. The results showed that for achieving the best G. versteegii growth, the G. versteegii should be planted under the community group which was dominated by Paraserianthes falcataria, T grandis, Gliricidia sepium and Eugenia aquea. Environmental factors affecting . , diameter growth of G. verteegii were organic carbon of the soil and the vegetation density. Meanwhile the environmental factors affecting the height growth of G. versteegii were temperature, light intensity, relative light intensity, organic carbon, C N ratio, P, Mg, air humidity, and clay content.

Tree breeding of teak results in selected clones with high growth. Intensive silviculture is required to support a large-scale clonal teak plantation. Appropriate spacing is one of the methods to increase forest plantation productivity. Research of teak clone spacing was conducted on a seven-year-old clonal teak plantation with randomized completely block design. The treatments tested in this study were four plant spacing distances, namely, 3 m × 3 m, 6 m × 2 m, 8 m × 2 m, and 10 m × 2 m. Results show that spacing had significantly different effects on diameter, height, bole height, branch angle, crown area, crown projections, volume, and competition index. However, the height growth did not exhibit any significant differences. The 10 m × 2 m spacing produced the best diameter growth, crown area, and competition index, but has a low volume per hectare and the lowest height of free branch and branch angle. Meanwhile, the 3 m × 3 m spacing will increase bole height and stand volume per hectare. This result suggests that spacing could improve the growth of teak clone but must be followed by intensification of proper maintenance to reduce branch angle and increase bole height.

Arrowroot (Maranta arundinacea L.) is an important starchy plant which has potential utilization for food, industry and medicine. The study was undertaken to assess the variability in morpho-physiological characters, tuber yield and starch content of 23 arrowroot populations in Garut District, West Java. The result showed some significant differences in morpho-physiological characteristics, tuber yield and starch content. Growth characteristics revealed that Cilawu population recorded the highest values for some characters: high, leaf number, abovegrowth biomass and tuber biomass. Cikajang population showed the highest tuber yield (210.6 g per plant) followed by Cilawu population (134 g per plant). Cikajang and Cilawu populations also provided the highest tuber biomass, 46.6 g and 60.0 g respectively. Cilawu population was a second population producing the highest starch content (26.1 %) after Cibatu population (27 %). The higher heritability coupled with genetic advance revealed for fresh tuber yield indicated that selection on basis of the character may be helpful to improve arrowroot yield. Most of the growth characteristics had not significant correlation indicating that the characteristics are not good indicator for selection. Cilawu, Cikajang and Cibatu populations have good potential to produce the high quality and quantity of tuber for arrowroot cultivation in Garut District.

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The selection of species for enrichment planting that involves native species in a secondary lowland dipterocarps forest as one of the tropical rainforest types should be conducted to maintain the sustainable management of tropical rainforests. The research of species trial of dipterocarp species was planted under a randomized complete block design with four replications. The following parameters were examined: survival rate, diameter breast height (DBH), pilodyn penetration (PP), and stress wave velocity (SWV). The survival rate (F ¼ 1.72; p ¼ 0.047), DBH (F ¼ 6.67, p < 0.0001), and pilodyn penetration (F ¼ 14.19; p < 0.001) significantly differed at 12.5 years after planting. The survival rate of Shorea leprosula was the highest (85%) of all the species, and the survival rate of other species, namely, S. macrophylla, S. ovalis, S. johorensis, S. scaberima, and S. parvifolia, was more than 70%. The best growth of DBH parameter was observed in S. platyclados. The DBH growth of S. platyclados 12.5 years after planting were 27.62 cm (mean annual diameter increment [MADI] ¼ 2.2 cm/year). The species whose growth in DBH was similar to those of S. platyclados were S. leprosula, S. parvivolia, and S. ovalis. However, stress wave velocity (SWV) was not significantly different among dipterocarp species (F ¼ 1.26; p ¼ 0.234). Pilodyn penetration (PP) was significantly correlated with DBH (Pearson's correlations ¼ 0.306; p < 0.001), whereas stress wave velocity was not significantly correlated with DBH and PP (p > 0.05), and their Pearson's correlations were 0.043 and À0.012, respectively. These results suggested that each dipterocarp species varied in terms of their growth and wood properties. Thus, choosing the species for enrichment planting in secondary tropical rainforests depends on the characteristics of each species and the desired final product of forest management.

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