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The development policies implemented in Jambi Province, Indonesia, since the New Order era, have encouraged transformations in demography, regional paradigms, growth base sectors, and growth actors. This study aims to understand how the central government’s demographic policies and plantation development program have impacted regional land cover change, rural development transformation, and economic development in Sumatra Island’s biodiversity-rich rainforest region (Jambi Province). This study explores the shifts in village typology that have occurred. Descriptive analysis and cluster analysis were applied to collect data at the provincial level that included population, poverty rate, levels of education, HDI, GRDP, Gini index, and land cover. Village Potential Data at the village level was then used to build an infrastructure index and a diversity of activities index. The results of this study indicated that macro development indicators are in a positive trend: HDI, educational levels, GRDP per capita, and the proportion of the tertiary sector in GRDP have all increased. The growth of the tertiary sector was largely driven by the trade and motorized-vehicle repair sectors. The provincial landscape has changed significantly due to the expansion of oil palm plantations. At the village level, the infrastructure index and diversity index show an increase in the number of facilities and variations in economic activity in most villages. Some shifts in rural typology are highlighted: the increase in urban villages and in villages that specialize in oil palm plantation or other industrial plantation crops.

Logging and habitat conversion create hotter microclimates in tropical forest landscapes, representing a powerful form of localised anthropogenic climate change. It is widely believed that these emergent conditions are responsible for driving changes in communities of organisms found in modified tropical forests, although the empirical evidence base for this is lacking. Here we investigated how interactions between the physiological traits of genera and the environmental temperatures they experience lead to functional and compositional changes in communities of ants, a key organism in tropical forest ecosystems. We found that the abundance and activity of ant genera along a gradient of forest disturbance in Sabah, Malaysian Borneo, was defined by an interaction between their thermal tolerance (CTₘₐₓ) and environmental temperature. In more disturbed, warmer habitats, genera with high CTₘₐₓ had increased relative abundance and functional activity, and those with low CTₘₐₓ had decreased relative abundance and functional activity. This interaction determined abundance changes between primary and logged forest that differed in daily maximum temperature by a modest 1.1°C, and strengthened as the change in microclimate increased with disturbance. Between habitats that differed by 5.6°C (primary forest to oil palm) and 4.5°C (logged forest to oil palm), a 1°C difference in CTₘₐₓ among genera led to a 23% and 16% change in relative abundance, and a 22% and 17% difference in functional activity. CTₘₐₓ was negatively correlated with body size and trophic position, with ants becoming significantly smaller and less predatory as microclimate temperatures increased. Our results provide evidence to support the widely held, but never directly tested, assumption that physiological tolerances underpin the influence of disturbance‐induced microclimate change on the abundance and function of invertebrates in tropical landscapes. A free Plain Language Summary can be found within the Supporting Information of this article.

Funding: The research was carried out as part of a project funded by the Malaysian Palm Oil Board (MPOB). L. K. K and E. R. are both employees of MPOB. The research was carried out with the support of Sarawak Oil Palm Berhard (SOPB) on whose land the research project was based. Need for regional economic development and global demand for agro‐industrial commodities has resulted in large‐scale conversion of forested landscapes to industrial agriculture across South East Asia. However, net emissions of CO2 from tropical peatland conversions may be significant and remain poorly quantified, resulting in controversy around the magnitude of carbon release following conversion. Here we present long term, whole ecosystem monitoring of carbon exchange from two oil palm plantations on converted tropical peat swamp forest. Our sites compare a newly converted oil palm plantation (OPnew) to a mature oil palm plantation (OPmature) and combine them in the context of existing emission factors. Mean annual net emission (NEE) of CO2 measured at OPnew during the conversion period (137.8 Mg CO2 ha‐1 yr ‐1) were an order of magnitude lower during the measurement period at OPmature (17.5 Mg CO2 ha‐1 yr‐1). However, mean water table depth (WTD) was shallower (0.26 m) than a typical drainage target of 0.6 m suggesting our emissions may be a conservative estimate for mature plantations, mean WTD at OPnew was more typical at 0.54 m. Reductions in net emissions were primarily driven by increasing biomass accumulation into highly productive palms. Further analysis suggested annual peat carbon losses of 24.9 Mg CO2‐C ha‐1 yr‐1 over the first 6 years, lower than previous estimates for this early period from subsidence studies, losses reduced to 12.8 Mg CO2‐C ha‐1 yr‐1 in the later, mature phase. Despite reductions in NEE and carbon loss over time, the system remained a large net source of carbon to the atmosphere after 12 years with the remaining 8 years of a typical plantation’s rotation unlikely to recoup losses. These results emphasise the need for effective protection of tropical peatlands globally and strengthening of legislative enforcement where moratoria on peatland conversion already exist. Publisher PDF

The expansion of oil-palm plantations in Indonesia is often blamed as the driving causes of deforestation and impacts on environmental changes including the destructed biodiversity. Our understanding regarding environmental impacts on biodiversity is still limited. We address this issue by examining the diversity of butterfly and bird species under two type habitat conditions in Central Borneo. We calculated the butterfly and bird species number, richness, evenness, similarity, and composition inside the established oil-plantation area comprising four large-scale plantations and seven smallholding plantations, as habitat after plantation establishment. In comparison, we did so similarly inside secondary forest and shrubs, as habitat before oil-palm plantation establishment. Our results revealed that the habitat after plantation establishment exhibited a higher number of butterfly and bird species than the habitat beforehand. However, the richness, evenness, and similarity indices for the species revealed variations, which were affected by dominant species in two habitats. The establishment of oil-palm plantation brought about significant impacts on the composition of species and affected the species similarities between two habitats. The oil-palm plantation landscape and reserved forest vegetation were essential in supporting diversity and ecological role of species on habitat condition after oil-palm plantation establishment.

Termites are vital members of old-growth tropical forests, being perhaps the main decomposers of dead plant material at all stages of humification (decay). Termite abundance and diversity drop in selectively logged forest, and it has been hypothesised that this drop is due to a low tolerance to changing micro-climatic conditions. Specifically, the thermal adaptation hypothesis suggests that tropical species are operating at, or close to, their thermal optimum, and therefore, small temperature increases can have drastic effects on abundance, however, other climatic variables such as humidity might also cause termite abundance to drop. We tested termite tolerance to these two climatic variables (temperature and humidity). We found that termites had a higher CTmax than expected, and that three traits, feeding group, body sclerotisation, and nesting type, were significantly correlated with CTmax. We found that termite desiccation tolerance was low, however, and that all termite genera lost significantly more water in a desiccated environment than in a control. Body sclerotisation, the only trait that was tested, was surprisingly not significantly correlated with desiccation tolerance. Our results suggest that desiccation, rather than ambient temperature, may be the determining factor in dictating termite distributions in modified forests. Should climate change lead to reduced humidity within tropical rainforests, termite abundances and the rates of the functions they perform could be severely reduced.

Syarifuddin, Hafnisiregar E, Jambak J, Suryani C. 2018. The impact of oil palm plantation on ecology of rambutan (Nephelium lappaceum) insect pollinators. Biodiversitas 19: 1347-1351. The establishment of oil palm plantation in Sumatra was the result of massive conversion of its rainforest. Many studies have shown that oil palm plantation is a main threat to biodiversity including insect pollinators. However, its effect on the ecology of insect pollinators is still poorly studied. In this study, we investigated the impact of oil palm plantation on the species richness and composition, abundance as well as pattern of time period and duration of insect visit on rambutan, Nephelium lappaceum, flowers. Insect visitors of flowers were compared between rambutan grown in the Oil Palm Plantation (OPP) ecotone and the one in the mixed Oil Palm Garden Forest (OPGF) ecotone. Number of visiting insects on each pannicle in ten minutes period and number of flowers and pannicles visited within 2 minutes were enumerated. The length of time of a randomly selected individual of the most abundant insects visited a flower and a pannicle was also recorded. The results showed that species composition of insect visitors was different between the two ecotones and total insect abundance was significantly higher on rambutan flowers located in the OPGF ecotone compared to rambutan trees grown close to oil palm plantation. The insect visitors on rambutan flowers in the OPGF ecotone were dominated by bees while in the OPP was dominated by Calliphorid fly. Among the main pollinators, the bee Apis cerana visited far more flowers and pannicles compared to Trigona sp and Chrysomya sp. Thus, more evidence showing that oil palm plantation probably has caused the disappearance of main species of bee pollinators, reduced abundance of flower-visiting insects, change of pollinator species composition, change of the pattern of time and change the duration of insect visit of rambutan flowers.

Diversity of parasitic Hymenoptera in different ecosystem types in Central Bangka, Bangka-Belitung Islands.Hymenoptera richness is dominated by parasitic species. More than 80% of Hymenoptera play a role as parasitoid on arthropods that are mostly insects. Diversity of parasitic Hymenoptera is widely studied in various types of terrestrial ecosystems including agro-ecosystem and non-agro-ecosystem. This study aimed to invent and compare the diversity of parasitic Hymenoptera in three different ecosystems, i.e., forest, oil palm plantation, and ex-tin mining. The location was located in Central Bangka Regency, Bangka Island. The study was conducted in Juli 2014 until October 2015. Parasitic Hymenoptera was collected with insect sweep net and yellow pan trap on one transect line with 1000 m length. Parasitic Hymenoptera were found on forest as much as 732 morphospecies, 326 morphospecies on oil palm plantations, and 293 morphospecies on ex-tin mining. Diversity and abundance of parasitic Hymenoptera on forest was higher than oil palm plantation and ex-tin mining area. Braconidae family was found dominant on forest, however on oil palm plantation and extin mining area the dominant family was Scelionidae.

The diversity of bacterial communities in aquatic sediment of rainforest and oil palm plantation at Sumatra was studied using pyrosequencing of 16S rRNA gene and common biodiversity indices. Phylogenetic approach was used for revealing the community shift of bacterial phyla and genera in both areas. Ecological approach used soil pH, total Carbon (TC), total Nitrogen (TN), available Phosphorus (AP) measurement and bacterial diversity with Shanon and Simpson indices, and bacterial richness with Chao1-ACE indices and OTUs. Bacterial diversity and richness in aquatic sediment of forest area was higher than that ones in oil palm plantation area, although their pH, TC, and TN in both areas were not different significantly. The majority of sequences related to Proteobacteria (34.85%), Acidobacteria (32.67%), Nitrospirae (6.86%), Chloroflexi (4.31%), and Actinobacteria (4.02%) were from forest; whereas those related to Acidobacteria (46.10%), Proteobacteria (25.86%), Nitrospirae (9.20%), Chloroflexi (4.99%), and Actinobacteria (2.34%) invented from oil palm plantation. The genera of Alphaproteobacteria and Betaproteobacteria dominated in genera phylotype of bacterial 16S rRNA phylogenetic revealed both aquatic sediment of forest and oil palm plantation. The most genera in the phylogenetic tree from aquatic sediment of both areas was Burkholderia. The bacterial community shift in aquatic sediment of forest transformation indicated higher bacterial diversity index, richness index, some of phyla and genera in aquatic sediment from forest than from oil palm plantation.

Understanding how anthropogenic disturbance influences patterns of community composition and the reinforcing interactive processes that structure communities is important to mitigate threats to biodiversity. Competition is considered a primary reinforcing process, yet little is known concerning disturbance effects on competitive interaction networks. We examined how differences in ant community composition between undisturbed and disturbed Bornean rainforest, is potentially reflected by changes in competitive interactions over a food resource. Comparing 10 primary forest sites to 10 in selectively-logged forest, we found higher genus richness and diversity in the primary forest, with 18.5% and 13.0% of genera endemic to primary and logged respectively. From 180 hours of filming bait cards, we assessed ant-ant interactions, finding that despite considered aggression over food sources, the majority of ant interactions were neutral. Proportion of competitive interactions at bait cards did not differ between forest type, however, the rate and per capita number of competitive interactions was significantly lower in logged forest. Furthermore, the majority of genera showed large changes in aggression-score with often inverse relationships to their occupancy rank. This provides evidence of a shuffled competitive network, and these unexpected changes in aggressive relationships could be considered a type of competitive network re-wiring after disturbance.

Agricultural land use is an artificial ecosystem. Insect pollinators are important keys to success of the agroecosystem. Converting natural landscapes to agricultural land, such as oil palm and rubber plantations, affects the insects. The research aims to study diversity and abundance of insect pollinators in three different agricultural land uses, i.e. oil palm plantation, rubber plantation, and jungle-rubber. Scan sampling method was used to explore the diversity of insect pollinators. Observations of the insects were conducted from 08.00 to 10.00 AM and 02.00 to 04.00 PM in sunny days. There were 497 individuals of insect pollinators collected, which belong to 43 species in three orders (Hymenoptera, Diptera, and Lepidoptera). Number of species and individual of insect pollinators found in rubber plantations (31 species, 212 individuals) and oil palm plantation (23 species, 188 individuals) were higher than that in jungle rubber (7 species, 97 individuals). Insect pollinators in oil palm plantations were dominated by giant honey bee (Apis dorsata) and stingless bee (Trigona sp. [=aff. T. planifrons]), whereas in rubber plantation, they were dominated by small carpenter bees (Ceratina lieftincki and Ceratina simillima), and in jungle-rubbers were dominated by hoverfly (Syrphid sp.) and Apis andreniformis. Higher foraging activities of insect pollinators occured in the morning.

Invertebrates are dominant species in primary tropical rainforests, where their abundance and diversity contributes to the functioning and resilience of these globally important ecosystems. However, more than one-third of tropical forests have been logged, with dramatic impacts on rainforest biodiversity that may disrupt key ecosystem processes. We find that the contribution of invertebrates to three ecosystem processes operating at three trophic levels (litter decomposition, seed predation and removal, and invertebrate predation) is reduced by up to one-half following logging. These changes are associated with decreased abundance of key functional groups of termites, ants, beetles and earthworms, and an increase in the abundance of small mammals, amphibians and insectivorous birds in logged relative to primary forest. Our results suggest that ecosystem processes themselves have considerable resilience to logging, but the consistent decline of invertebrate functional importance is indicative of a human-induced shift in how these ecological processes operate in tropical rainforests., Invertebrates are key components in the ecological functioning of tropical forests. Here, Ewers et al. show that, compared to primary forest, logging halves the contribution of invertebrate species to several key ecosystem processes, including litter decomposition.

International audience; For sustainable oil palm production, barn owl (Tyto alba) predation should be enhanced and monitored to better understand its impact on rodent population dynamics, notably for selective predation based on age or size. Our aim was to assess the best combination of osteometric variables that predict eye lens weight and thus the relative age of an individual Rattus tiomanicus based on pellet remains. We captured 161 individuals in an oil palm plantation in Indonesia and measured 15 osteometric variables for the jaw, skull, and femur. We investigated the variables’ correlations with eye lens weight and estimated the measurement errors. In addition, 120 pellets were collected to assess the frequency of different types of bones. Predictive modelling was then used. We suggest that the model using the femur length would be more appropriate, even if it is slightly less precise than the models that consider the skull and jaw variables. The femur was well represented in the pellet sample, its length highly correlated with the eye lens weight, with a low measurement error. Our study demonstrates the utility of femur length for age prediction in prey from macroremains in oil palm plantations, wherein most pellets are headless and R. tiomanicus is the dominant prey.

"Results from remote sensing analysis, participatory mapping, socio-economic interviews, and hotspot information that were analyzed in a geographic information system (GIS) show how fire has changed the landscape through its use in land preparation for oil palm and timber plantations and in the development of transmigration settlements. These timber and oil palm plantations have greatly altered the livelihood options of the communities, and have created conflict between communities and companies over land-use allocation and tenure. In many cases, conflict over tenure has been the motive for forest and land fires during the annual dry season. The study suggests that, where partnerships between communities and companies were established to develop oil palm and timber plantations that included a greater sharing of benefits and use of land, the incidence of fires designed to damage the planted resource was greatly reduced."