Bambang Irawan

• Dean at Jambi University

In monoculture-dominated landscapes, recovering biodiversity is a priority, but effective restoration strategies have yet to be identified. In this study, we experimentally tested passive and active restoration strategies to recover taxonomic, phylogenetic, and functional diversity of woody plants within 52 tree islands established in an oil palm l...

Vegetation structural complexity has been identified as a vital factor for forest ecosystem function, stability, and resilience. However, agricultural land with much reduced structural complexity has largely replaced natural forests in the tropics. Therefore, restoring structural complexity in large-scale plantation monocultures by introducing agro...

The expansion of the oil palm industry in Indonesia has improved livelihoods in rural communities, but comes at the cost of biodiversity and ecosystem degradation. Here, we investigated ways to balance ecological and economic outcomes of oil palm cultivation. We compared a wide range of production systems, including smallholder plantations, industr...

In tropical regions, shifting from forests and traditional agroforestry to intensive plantations generates conflicts between human welfare (farmers’ demands and societal needs) and environmental protection. Achieving sustainability in this transformation will inevitably involve trade-offs between multiple ecological and socioeconomic functions. To...

Plant diversity effects on community productivity often increase over time. Whether the strengthening of diversity effects is caused by temporal shifts in species-level overyielding (i.e., higher species-level productivity in diverse communities compared with monocultures) remains unclear. Here, using data from 65 grassland and forest biodiversity...

Introduction High-throughput sequencing (HTS) provides an efficient and cost-effective way to generate large amounts of sequence data, providing a very powerful tool to analyze biodiversity of soil organisms. However, marker-based methods and the resulting datasets come with a range of challenges and disputes, including incomplete reference databas...

High-throughput sequencing (HTS) provides an efficient and cost-effective way to generate large amounts of sequence data. However, marker-based methods and the resulting datasets come with a range of challenges and disputes, including incomplete reference databases, controversial sequence similarity thresholds for delineating taxa, and downstream c...

Conventional management of oil palm plantations, involving high fertilization rate and herbicide application, results in high yield but with large soil greenhouse gas (GHG) emissions. This study aimed to assess a practical alternative to conventional management, namely reduced fertilization with mechanical weeding, to decrease soil GHG emissions wi...

Optimizing restoration outcomes is crucial for enhancing multifaceted diversity, resilience, and ecosystem functioning in monoculture-dominated landscapes globally. Here, we experimentally tested the performance of passive and active restoration strategies to recover taxonomic, phylogenetic, and functional diversity by establishing 52 tree islands...

Enhancing biodiversity in monoculture-dominated landscapes is a pressing restoration challenge. Planted tree islands can enhance biodiversity locally, but the role of processes at larger spatial scales is unclear. Using a multi-scale approach, we explored how these scale-dependent processes influence the diversity of seven taxa (woody plants, under...

Conventional management of oil palm plantations, involving high fertilization rate and herbicide application, result in high yield but with large soil greenhouse gas (GHG) emissions. This study aimed to assess a practical alternative to conventional management, namely reduced fertilization with mechanical weeding, to decrease soil GHG emissions wit...

Honey is a valuable non-timber forest product widely consumed by communities, with those living near forests sourcing it both from the wild and cultivation. Jujun Village, supported by the Faculty of Agriculture at Jambi University, received assistance in honeybee farming through the Wira Desa program from the Department of Forestry in 2021. As a n...

Enhancing biodiversity in monoculture-dominated landscapes is a key sustainability challenge that requires considering the spatial organization of ecological communities (beta diversity). Here, we tested whether increasing landscape heterogeneity, through establishing 52 tree islands in an oil-palm landscape, is a suitable restoration strategy to e...

In the United Nations Decade on Ecosystem Restoration¹, large knowledge gaps persist on how to increase biodiversity and ecosystem functioning in cash crop-dominated tropical landscapes². Here, we present findings from a large-scale, 5-year ecosystem restoration experiment in an oil palm landscape enriched with 52 tree islands, encompassing assessm...

Oil palm is the most productive oil crop, but its high productivity is associated with conventional management (that is, high fertilization rates and herbicide application), causing deleterious environmental impacts. Using a 2² factorial experiment, we assessed the effects of conventional vs reduced (equal to nutrients removed by fruit harvest) fer...

In the presence of market inefficiencies and missing information, agricultural technologies have often been introduced via subsidies to accelerate diffusion and spur adoption. Yet, for agricultural technologies that mainly generate positive environmental effects, it is not clear how subsidies affect adoption, maintenance, and additional investments...

How to enhance biodiversity in monoculture-dominated landscapes is a key sustainability question that requires considering the spatial organization of ecological communities (beta diversity). Here, we experimentally tested if increasing landscape heterogeneity - through tree islands - is a suitable landscape restoration strategy when aiming to enha...

Logged forests cover four million square kilometers of the tropics, capturing carbon more rapidly than temperate forests and harboring rich biodiversity. Restoring these forests is essential to help avoid the worst impacts of climate change. Yet monitoring tropical forest recovery is challenging. We track the abundance of early-successional species...

The availability of land cover in the form of forest is very important in the watershed system (DAS). The decrease in forest cover and the carbon content stored in a watershed also shows a decline in the quality of the watershed. The research aims to examine changes in land cover that occurred during the last twenty years in the Pengabuan Watershed...

To secure high yield, tropical oil palm plantations are fertilized, and understory vegetation is controlled by chemical clearing with herbicides. These treatments cause a drastic turnover of soil microbes and cause loss of beneficial mycorrhizal fungi. Here, we tested if reduced fertilization and weeding instead of conventional treatments restored...

The response of tropical trees to the change of light intensity has been reported to be varied among different species. Some reports argued that the growth was increasing parallel to the increasing of light intensity, but other reports mentioned that the sensitivity to the light intensity was depending on the species. Another environmental factor t...

Microclimate and Land Surface Temperature (LST) are important analytical variables used to understand complex oil palm agroforestry systems and their effects on biodiversity and ecosystem functions. In order to examine experimental effects of tree species richness (0, 1, 2, 3 or 6), plot size (25 m², 100 m², 400 m², 1600 m²) and stand structural co...

Agroforestry options such as mixed-species tree planting and natural regeneration in oil palm plantations may alleviate negative effects of forest loss on biodiversity and ecosystem functioning. The effects of agroforestry on microclimate and land surface temperatures (LST) remain largely unknown despite their central role in controlling abiotic an...

In tropical landscapes dominated by oil palm monocultures, scattered trees can contribute to biodiversity, regulate diverse ecosystem functions and deliver goods and services. However, basic quantitative information about such trees is often lacking. The objectives of our study were to identify the landscape-wide density and distribution patterns o...

Rainforest conversion to woody croplands impacts the carbon cycle via ecophysiological processes such as photosynthesis and autotrophic respiration. Changes in the carbon cycle associated with land-use change can be estimated through Land Surface Models (LSMs). The accuracy of carbon flux estimation in carbon fluxes associated with land-use change...

The conversion of highly diverse tropical lowland rainforests to monocultures of oil palm and rubber leads to drastic changes in fungal community structures. The magnitude of structuring effects, driven by changes in root or soil properties, on trophic groups with different ecological functions (mycorrhiza, saprotrophs, and pathogens) remains unkno...

Financially profitable large-scale cultivation of oil palm monocultures in previously diverse tropical rain forest areas constitutes a major ecological crisis today. Not only is a large proportion of the aboveground diversity lost, but the belowground soil microbiome, which is important for the sustainability of soil function, is massively altered....

Native tree planting in oil palm plantations represents one management option to increase biodiversity in oil palm dominated landscapes. Using a randomized controlled trial, we test which policy options can promote tree planting. Our policy interventions include pure information provision and a combination of information and free seedling provision...

Logged forests cover four million square kilometres of the tropics and restoring these forests is essential if we are to avoid the worst impacts of climate change, yet monitoring recovery is challenging. Tracking the abundance of visually identifiable, early-successional species enables successional status and thereby restoration progress to be eva...

Conversion of lowland tropical rainforests to intensely fertilized agricultural land-use systems such as oil palm (Elaeis guineensis) plantations leads to changes in nitrogen (N) cycling. Although soil microbial-driven N dynamics has been largely studied, the role of the plant as a major component in N uptake has rarely been considered. We address...

Kabupaten Tanjung Jabung Barat memiliki tanaman kelapa dengan luasan 38.546 Ha dengan produktivitas sebesar 50.494 ton dan produktivitas perhektarnya sebesar 1,2ton/ha (Statistik Perkebunan, 2013 dalam Kemala, 2015). Salah satu sentra penghasil kelapa di Kabupaten Tanjung Jabung Barat adalah di Kecamatan Tungkal Ilir Desa Tungkal I Dusun Bahagia. D...

This study evaluates the effects of two policy instruments on the adoption of native tree planting in oil palm plantations. The first instrument is an information campaign on tree planting in oil palm. The second instrument combines the information campaign with a structural intervention that provides native tree seedlings for free. We implemented...

Oil palm plantations are intensively managed agricultural systems that increasingly dominate certain tropical regions. Oil palm monocultures have been criticized because of their reduced biodiversity compared to the forests they historically replaced, and because of their negative impact on soils, water, and climate. We experimentally test whether...

Due to over exploitation, the population of Eusideroxylon zwageri is decreasing drastically. One simple technique to conserve the last remaining genetic resources of E. zwageri is by air layering. The experiment was divided into two. The experiment was conducted from July 2018 to February 2019. The first experiment was conducted using branches that...

Large‐scale conversion of tropical forests into oil palm monocultures has led to dramatic losses of biodiversity and ecosystem functions. While ecological restoration is urgently needed in many oil palm landscapes, there is a lack of scientific knowledge of sustainable management strategies. We established experimental tree islands of varying sizes...

Oil palm monocultures are highly productive, but there are widespread negative impacts on biodiversity and ecosystem functions. Some of these negative impacts might be mitigated by mixed-species tree interplanting to create agroforestry systems, but there is little experience with the performance of trees planted in oil palm plantations. We studied...

Soil fungi are key players in nutrient cycles as decomposers, mutualists and pathogens, but the impact of tropical rain forest transformation into rubber or oil palm plantations on fungal community structures and their ecological functions are unknown. We hypothesized that increasing land use intensity and habitat loss due to the replacement of the...

Renewable energy opens up prospects for answer the problem and an eco-friendly solution directed to energy security. Indonesia as a rich country of biodiversity resources, has a high potential for developing new and renewable energy derivates from plants. One of those biodiversity resources that had been investigated is nipah (Nypa fruticans Wurmb)...

Renewable energy opens up prospects for answer the problem and an eco-friendly solution directed to energy security. Indonesia as a rich country of biodiversity resources, has a high potential for developing new and renewable energy derivates from plants. One of those biodiversity resources that had been investigated is nipah (Nypa fruticans Wurmb)...

Plant species have different abilities to sequester and to store carbon in a forest ecosystem. The content of fixed carbon in the forest biomass shows its suitability as bioenergy resources. Biomass with a higher fixed carbon content can produce more energy. The proximate analysis was conducted on nine types of lignocellulosic materials, such as Te...

The objectives of this study were to evaluate the effects of sublethal cadmium concentrations on the levels of cadmium, metallothionein and histological changes in gills of East Java strain tilapia (Oreochromis niloticus) at different salinity levels. Cadmium concentrations in the control groups (without cadmium) at all tested salinities ranged fro...

The expansion of oil-palm plantations threatens tropical biodiversity and ecosystem functioning. While the expansion of oil palm has been associated with positive welfare effects, the strong dependence of local livelihoods on a single crop species also entails social and economic risks. Alternative management strategies could be important in mitiga...

Tropical biodiversity is threatened by the expansion of oil-palm plantations. Reduced-impact farming systems such as agroforests, have been proposed to increase biodiversity and ecosystem functioning. In regions where oil-palm plantations already dominate the landscape, this increase can only be achieved through systematic ecological restoration. H...

Smallholder-dominated agricultural mosaic landscapes are highlighted as model production systems that deliver both economic and ecological goods in tropical agricultural landscapes, but trade-offs underlying current land-use dynamics are poorly known. Here, using the most comprehensive quan-tification of land-use change and associated bundles of ec...

Primer pair sequences for plants, bacteria, and archaea

Supplementary Figures 1 - 9, Supplementary Tables 1 - 5, Supplementary Note 1 and Supplementary References

Tropical lowland rainforests are increasingly threatened by the expansion of agriculture and the extraction of natural resources. In Jambi Province, Indonesia, the interdisciplinary EFForTS project focuses on the ecological and socio-economic dimensions of rainforest conversion to jungle rubber agroforests and monoculture plantations of rubber and...

Two series of a study on the correlation between soil properties and distribution of ironwood (Eusideroxylon zwageri Teijsm.&Binn.) varieties had been conducted in Senami, a natural foreststand, Jambi,Indonesia. The firstwas using purposive random sampling. The samples were taken from the locations where the E. zwageri varieties naturally grow in t...

The analysis of indigenous knowledge, morphological observations, and molecular variation are valid approaches to study plant biodiversity. A combination of these complementary methods allows a better understanding of the diversity within ironwood (Eusideroxylon zwageri Teijsm. et Binn.), an endangered ‘wild’ tropical tree species, at molecular and...

Four Eusideroxylon zwageri Teijsm. & Binn. varieties had been described. A study on growth performance of one-year old seedlings of E. zwageri varieties had been conducted to study the comparison of shoot growth performance and survival among E. zwageri varieties. The varieties were exilis, grandis, ovoidus, and zwageri. The study was conducted in...

Four Eusideroxylon zwageri Teijsm. & Binn. varieties had been described. A study on growth performance of one-year old seedlings of E. zwageri varieties had been conducted to study the comparison of shoot growth performance and survival among E. zwageri varieties. The varieties were exilis, grandis, ovoidus, and zwageri. The study was conducted in...

Zugl.: Göttingen, Universiẗat, Diss., 2004.

Ironwood (Bulian/ulin/belian/borneo ironwood) (Eusideroxylon zwageri T.et B.) belongs to family of Lauraceae, tribus of cryptocaryeae and subtribus of Eusideroxylineae. It is one of the most important construction wood in Indonesia because it is not vulnerable to termites and other ubiquitous tropical wood-destroying insects and fungi. Research on...

/ha) Balam Palaquium sp (Pa) 0.33 21.40 9.21 0.77 12.42 Bulian E. zwageri (Ez) 0.26 24.68 19.98 1.10 5.18 Jelutung D. costulata (Dc) 0.33 12.00 1.16 0.09 0.72 Kacang-kacang S. javanica (Sj) 0.20 8.00 0.91 0.03 0.18 Keruing Dipterocarpus sp. (Di) 0.37 17.00 1.26 0.11 1.28 Medang Litsea sp. (Li) 0.29 15.60 19.02 0.99 11.07 Meranti Shorea sp. (Sh) 0.2...