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Since its inception and until now, oil palm plantations have been controversial in Indonesia. Although there is ample evidence presented by proponents proving that oil palm expansion has made an important contribution to the Indonesian economy, from an ecological point of view, it is claimed by critics to have negative impacts on the environment, one of which is the cause of natural disasters. The link between oil palm expansion and natural disasters is debated between critics and supporters of oil palm expansion. This study examines the theme of criticism of oil palm expansion as a cause of natural disasters and counter-discourse of supporting oil palm expansion. By using literature study methods and an environmental, sociological perspective, it is found that the discourse on the impact of oil palm plantation expansion shows a contradiction between the views of the New Ecological Paradigm (Paradigma Ekologi Baru or PEB) and the Human Exemptionalism Paradigm (Paradigma Keterpisahan Manusia or HEP). The Indonesian government is building a counter-discourse of ecological modernization to maintain and develop oil palm plantations expansion.

The leopard cat (Prionailurus bengalensis) is the most widespread feline in Asia. It has been recorded in a range of habitats, including monoculture landscapes, such as oil palm plantations. Here, we report on a study on the presence, home range, activity patterns and diet of the species in an oil palm landscape to assess their viability as biological pest controller of rats. The study took place in United Plantations/PT SSS estate in Central Kalimantan, Borneo, Indonesia. From July 2014 to March 2018, we captured 11 leopard cats in purpose-built cage-traps and fitted them with VHF radio-transmitters. They were tracked for a 44 months study period, during which we collected a total of 2.031 GPS locations used for estimating the respective cats’ activities and home-ranges. The cats are strictly nocturnal and prefer to hide and rest in thick bush, primarily consisting of sword-fern (Nephrolepis sp.) during day-time, but forage both on the ground and in the palm canopy at night. The average home range (95% FK) for male leopard cats is 1.47 km2 (n = 7; SD = 0.62 km2) with slightly smaller home range for females at 1.29 km2 (n = 4; SD = 0.28 km2). All individuals studied were recorded strictly within the oil palm plantation landscape, although mangrove forest habitat makes up 7% of the greater plantation landscape. In conclusion, leopard cats survive and reproduce well in oil palm habitats and are effective biological controllers of rats that can replace the traditionally used expensive and environmentally polluting chemical rat poisons.

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

A field trial experiment was conducted to investigate the degradation of metsulfuron-methyl at two application dosages, 15 g a.i/ha and 30 g a.i/ha, at an oil palm plantation. Soil samples were collected at ‒1, 0, 1, 3, 7, 14, and 21 days after treatment (DAT) at the following depths: 0&ndash, 10, 10&ndash, 20, 20&ndash, 30, 30&ndash, 40, and 40&ndash, 50 cm. The results showed rapid degradation of metsulfuron-methyl in the soil, with calculated half-life (t&frac12, ) values ranging from 6.3 and 7.9 days. The rates of degradation of metsulfuron-methyl followed first-order reaction kinetics (R2 = 0.91&ndash, 0.92). At the spray dosage of 15 g a.i/ha, metsulfuron-methyl residue was detected at up to 20&ndash, 30 cm soil depth, at 3.56% to 1.78% at 3 and 7 DAT, respectively. Doubling the dosage to 30 g a.i/ha increased the metsulfuron-methyl residue in up to 30&ndash, 40 cm soil depth at 3, 7, and 14 DAT, with concentrations ranging from 1.90% to 1.74%. These findings suggest that metsulfuron-methyl has a low impact on the accumulation of the residues in the soil at application dosages of 15 g a.i/ha and 30 g a.i/ha, due to rapid degradation, and the half-life was found to be 6.3 to 7.9 days.

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.

Kwatrina RT, Santosa Y, Bismark M, Santoso N. 2018. The impacts of oil palm plantation establishment on the habitat type, species diversity, and feeding guild of mammals and herpetofauna. Biodiversitas 19: 1213-1219. Indonesia is the world’s largest producer of palm oil. Contributing 2.14% to the country’s gross domestic product, palm oil plays an important role in the national economy from plantation sector. However, the expansion of oil palm plantations has brought negative impacts to forests and wildlife. Little is known to what extent these negative impacts on mammals and reptiles can be reduced through better management. To address this knowledge gap, the current study assessed species diversity as affected by the establishment of the oil palm plantation in Central Kalimantan, a tropical biodiversity hotspot in Asia. We conducted 25 line transect surveys and visual encounter surveys in oil palm areas, shrubs and secondary forests in these landscapes. The results indicated that the establishment of oil palm plantation negatively impacted species abundance and diversity, and changed the mammal and reptile species composition, by favoring ecologically generalist species. For forest specialist species, forested areas like HCV and HCS, play an important role in maintaining habitat heterogeneity in oil palm landscapes. Mammal species found in habitat conditions following oil palm plantations belong to some feeding groups, whereas all species of herpetofauna have terrestrial habitat types. These mammal and herpetofauna species can live and function in the food chain in the oil palm plantation ecosystem.

The increasing global demand for vegetable oils has resulted in a significant increase in the area under oil palm in the tropics during the last couple of decades, and this is projected to increase further. The Roundtable on Sustainable Palm Oil discourages the conversion of peatlands to oil palm and rubber plantations. However, our understanding of the effects on soil organic carbon (SOC) stocks and associated greenhouse gas (GHG) emissions of land use conversion is incomplete, especially for mineral soils under primary forests, secondary forests, rubber and other perennial plantations in the tropics. In this review we synthesised information on SOC stocks and GHG emissions from tropical mineral soils under forest, oil palm and rubber plantations and other agroecosystems across the tropical regions. We found that the largest SOC losses occurred after land use conversion from primary forest to oil palm and rubber plantations. Secondary forest and pasture lands showed lower SOC losses as well as total GHG (CO2, N2O and CH4) emissions when converted to oil palm and rubber plantations. However, due to the limited data available on all three GHG emissions, there remains high uncertainty in GHG emissions estimates, and regional GHG accounting is more reliable. We recommend long-term monitoring of oil palm and other perennial plantations established on tropical mineral soils on different soil types and regions on SOC stock changes and total GHG emissions and evaluate appropriate management practices to optimise production and sustainable economic returns, and minimise environmental impact.

Swamp forests on deep tropical peatlands have undergone extensive deforestation and draining for agriculture and plantations, consequently becoming globally significant carbon (C) sources. To study the effects of land-use change on peat as a biological environment, which directly affects decomposition dynamics and greenhouse gas emissions, we sampled peat from four common land-use types representing different management intensities in Central Kalimantan, Indonesia. The near-pristine swamp forest was used to describe unmanaged conditions, and the three other sites in order of increasing management intensity were reforested; degraded; and agricultural. We examined peat substrate quality (total C & nitrogen (N), dissolved organic C (DOC) and N (DON)), organic matter quality characterized by infrared spectroscopy, and microbial biomass and extracellular enzyme activity, to describe both biotic and abiotic conditions in peat. We found that the peat at altered sites was poorer in quality, i.e. decomposability, as demonstrated by the higher intensity of aromatic and aliphatic compounds, and lower intensity of polysaccharides, and concentration of total N, DOC, and DON compared to the peat in the swamp forest. The observed differences in peat properties can be linked to changes in litter input and decomposition conditions altered after deforestation and draining, as well as increased leaching and fires. The quality of the peat substrate was directly related to its biotic properties, with altered sites generally having lower microbial biomass and enzyme activity. However, irrespective of management intensity or substrate quality, enzyme activity was limited primarily to the first 0–3 cm of the peat profile. Some differences between wet and dry seasons were observed in enzyme activity especially in swamp forest, where the most measured enzyme activities were higher in dry season. Reforestation 6 years before our measurements had not yet restored enzyme activity in the peat to the level of the swamp forest, although the topmost peat characteristics in the reforested site already resembled those in the swamp forest. This is likely contributed by the limited capacity of the young tree stand to produce litter to support peat formation and restore the quality and structure of the peat, and the chemical weed control performed at the site. Therefore, we conclude that intensive land management, including deforestation and draining, leads to the surface peat becoming poorer biological environment, and it may take long time to restore the peat properties.

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.

RSPO is sustainable. It is one of many certification labels to justify a sustainable palm oil practice. The objective of this study is to identify monetary benefit and cost with the existing operating scenario of the company, or if the company is registered as the RSPO member. To identify the benefit or cost that might occur, this research compared the NPV, IRR, and benefit-cost ratio among the alternative scenarios. An ex-ante projective cash flow is simulated using the company’s historical financial report from year 2012-2016 to obtain monetary perspective of the amount of money required by the plantation to proceed with certification. Certification should cost the plantation around 466 billion rupiahs with only 66 billion rupiahs of additional income from CPO premium if the company is able to complete its certification by 2019. Total benefit of income obtained from selling the certified products of CPO and PKO may cover the certification expense which does not exceed the cost paid with the discrepancy of 331 billion rupiahs. This amount can be used to establish another palm oil plantation, create jobs and contribute to domestic products. However, the net monetary loss is close to the value obtained from timber upon land clearing, which was at 286 billion rupiahs. Being sustainable is probably never about monetary value but more about the responsibility of managing the sustainable oil palm plantation and the environment that must be taken care of. Keywords: RSPO, oil palm plantation, cost and benefit analysis, oil palm in Papua, RSPO finansial benefit