Theme 3 blog update: Malaysian Borneo field trials 2016-2025

We established our large-scale field trials at the Sabahmas Plantations Sdn. Bhd. palm oil plantation in Sabah, Malaysian Borneo, in Phase 1 of the project to investigate ERW and crop performance in basalt-treated versus control conditions. The potential for carbon sequestration by enhanced weathering is expected to be highest in the tropics, given the warm and wet tropical climate, combined with nutrient-depleted and acidic soil conditions and yet highly productive vegetation.

The enormous extent over which oil palm is planted in Malaysian Borneo (7 million hectares) and the prevailing warm humid climate, which favours rapid weathering, makes it a leading candidate crop for application of ERW technology.  

Our experiments have taken place in coupes of palms being replanted and that are mature (12 years) to investigate effects as plantations mature and during post-tree removal. Find out more about our progress each year since LC3M began in 2016. 

Jump to:

• 2016-2017
• 2017-2018
• 2018-2019
• 2019-2020
• 2020-2021
• 2021-2022
• 2022-2023
• 2023-2024
• 2024-2025
• Papers featuring our Malaysian Borneo trials

2016-2017 

Our geochemists have visited the oil palm (Elaeis guineensis) plantations at Sabahmas, a subsidiary of Wilmar International, and begun identifying potential catchments for field trials. Our pot-based experimental investigations are underway and focusing on oil palm and targeted tree species important in tropical plantations and forest restoration. Alongside oil palm, we are investigating Acacia (N₂- fixer with rhizobia) and Eucalyptus as key tropical timber cropping plantation forest species, covering around 8 million hectares and 18 million hectares globally, respectively, sourced from Sabah Softwoods, Berhad. We are also investigating fast growing “pioneer” species used in reforestation programmes, sourced from the Sabah Forest Research Centre, Sepilok, with the long-term view that basalt treatments could help promote reforestation by restoring degraded soils whilst simultaneously capturing carbon. Basalt rock dust has been sourced and delivered from our supplier in Tawau into Danum at SEARRP. All species are grown in pots with Oxisol soils, inside a large 3.2m tall shade house at Danum. Over the next year, this large replicated experiment will provide initial datasets on the treatment effects across this range of tropical trees with differing root microbial symbionts and guide field trials in the next phase of the programme.

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2017-2018 

Three pairs of control and experimental (basalt) catchments (~1 ha per catchment) were identified within Sabahmas Plantations Sdn. Bhd. that are appropriate for the study of chemical weathering rates and monitoring of oil palm growth, yield, and herbivory resistance (see below). In each catchment sediment traps were installed to measure landscape erosion rates and lysimeters installed to collect soil pore waters. Stream flumes and gauge stations were also installed to measure stream discharge, turbidity, and dissolved oxygen content. 36 palms were tagged for long-term monitoring in each catchment, and their diameter, height, leaf area damage and chlorophyll content were measured. 

An on-site chemistry lab has been set up with housing provided by Wilmar International, and the Research Assistants received a 3-week training course on how to collect water samples and make in-situ geochemical measurements (pH, temperature, electrical conductivity, and alkalinity). Preliminary (pre-basalt application) stream and soil water samples were collected from each catchment and measured for major cation and anion concentrations. These samples confirmed that the geochemistry of each control- and experimental-catchment pair is similar, thus validating the experimental design. In preparation for basalt application, 75 tonnes of basalt has been transported from Onika Quarry to the field site. To date, around 50 tonnes of basalt have been bagged for application (about 2,500 bags). Basalt will be applied to the experimental catchments at a rate of 50 t ha^-1 yr^-1. Basalt powder application began in mid-June 2018.

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2018-2019 

During the 2018/2019 research season, the LC3M field site at Sabahmas Oil Palm Plantation, Malaysian Borneo became fully operational. Approximately 210 tonnes of basalt was transported from Onika Quarry, Tawau to the site. 10,500 gunny sacks were filled with basalt (around 20kg/bag) and applied from August to December 2018. Building on the 3 pairs of control and experimental (basalt) catchments that were established in 2017/2018, the field site was expanded to include an additional 10 pairs of control and experimental oil palm plots, each 60m × 60m. The 10 additional pairs will be used to monitor oil palm growth, yield and herbivory resistance. In each of the13 pairs, 36 palms were tagged, marked and measured for their diameter, height, leaf area damage and chlorophyll content before basalt application. We will re-measure them in June 2019, approximately 6 months after basalt was applied. Water sample collection (streams, soil pore water, and rain) commenced in October 2018. Stream samples were analysed on-site for electrical conductivity, pH, and alkalinity (see below) and all water samples have been analysed for major cation concentrations.

Initial geochemical results suggest that there is a rapid weathering response to basalt application. Unexpectedly, data from the 3 pairs of control and experimental (basalt) catchments indicate that ~3 months after basalt was applied to the experimental catchments, stream water alkalinity concentrations declined rather than increased, relative to the control catchments (see below).

Alkalinity is largely comprised of bicarbonate (HCO₃^-), the carbon storage reservoir produced by chemical weathering. These surprising results suggest that CO₂ consumption rates are lower in the basalt-treated catchments as compared to the control catchments. Future work will investigate why alkalinity concentrations declined (e.g. formation of secondary minerals, such as carbonate) and track whether this trend continues over a longer timeframe.

2019-2020 

The 2019/2020 field season ran according to plan until the end of March 2020 when an outbreak of COVID-19 led to the temporary closure of both field and laboratory activities on the instruction of the government. Operations were subsequently permitted to recommence on 8^th June 2020 – we are relieved!

Analysis of alkalinity data collected from the three pairs of experimental catchments to date together with stream discharge data (that is continually logged at each of the field sites) reveals that the rate of carbon dioxide removal from the atmosphere by weathering processes in the oil palm catchment (both control and basalt-applied sites) is extremely high: around 7 x 10⁶ mol/km²/yr. These carbon dioxide removal rates are comparable to rapidly eroding small basaltic islands (0.3 – 6.4 x 10⁶ mol/km²/yr), and indicate that catchments in warm and wet climates dosed with crushed silicate rock are particularly well-suited to carbon dioxide removal via enhanced rock weathering.

Cumulative removal of atmospheric carbon dioxide via alkalinity generation for one of the paired control and basalt-treated catchments is shown in the graph below. As of 1^st January 2020 the uptake of atmospheric CO₂ via weathering had been enhanced by ~15% through the addition of basalt. Carbon dioxide capture in the basalt catchment continues to increase relative to the control catchment and may be expected to be higher than this value by the end of 2020. Atmospheric CO₂ may also be removed via the generation of pedogenic carbonate; thus quantifying this will be a key focus of our activities over the coming year.

The application of crushed basalt is also having an impact on palm yields and resistance to herbivores. Those palms producing fruits in basalt-treated catchments had approximately 38% higher yields than those in the control catchments (see below); they were also better defended against insect herbivory (loss of leaf area was reduced by ~20%) than palms from the control catchments.

(a) Comparison of the increase in cumulative CO₂ removal (CDR) from the small-scale pilot ERW study in East Anglia, UK, and Sabahmas Plantations Sdn. Bhd. oil palm catchment in Lahad Datu Sabah, Malaysian Borneo, where the extent of CDR is defined as the difference in CO₂ removal via alkalinity generation between a basalt-treated catchment (dosed at 40 t ha^-1) and an untreated (control) catchment. Note that the magnitude of CO₂ removal is much higher in Malaysia relative to the UK, as its warm and wet climate effects higher weathering rates.

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2020-2021

Our ERW field trials were again impacted to some extent by government-enforced lockdowns related to COVID19 between October and December 2020. A further 50 tonnes/ha of basalt was applied to the large experimental catchments between September 2020 and March 2021; application took longer than usual as it had to be suspended during the COVID lockdown. A further 40kg of basalt was applied to each palm in the 10 paired palm-focused plots. 

We continued to measure palm diameter and height and leaf chlorophyll content index and damage every 6 months, and soil and leaf samples were collected. In 2020, the palms produced harvestable fruits for the first time and palm yield (total fruit bunch weight/palm in kg) was quantified for all study plots in late September 2020 and again in January 2021. Stream water samples, soil water samples, sediment run-off and soil samples were collected as usual, although water sampling had to be suspended between October and December 2020 due to the lockdown. 

We are working to quantify the potential contribution of fertiliser treatment to stream water chemistry. Initial analysis of elemental molar ratios suggests that fertilisers contribute to the loadings of Ca, Mg and Sr in stream waters. By contrast, there were no significant variations in stream water nutrient loadings between the basalt-amended and control plots. Soil carbonate concentrations are extremely low in both basalt-amended and control plots and below the detection limit of most techniques. To redress this, we have conducted soil leaching procedures to chemically isolate the soil exchangeable and soil carbonate fractions. In this way, we have shown that the soils contain ~0.05-0.1 wt% CaCO₃ and, as yet, there is no statistically significant difference in the CaCO₃ content of basalt-amended vs control soils. 

A total of 936 palms continue to be measured for growth, resistance to disease and pests, and fruit yield. Between 2019 and 2021, the relative changes in palm diameter and palm height were statistically identical between basalt-amended and control plots. Palms located in basalt-amended plots showed a slight improvement in photosynthetic capacity compared to control plots, that is potentially related to the easing of herbivory.

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2021-2022

Atmospheric CO₂ drawdown has been quantified via the export of alkalinity in stream waters and the change in soil carbonate content. The silicate-rock amended and reference catchments were found to have a similar extent of CO₂ drawdown via alkalinity export (respectively, 3.8±0.8 (1SD) and 3.7±0.6 (1SD) tCO₂ ha^-1) when all catchments were averaged over the study period (October 2018 to July 2021) (see below). However, we observed differences between the different plots: two of the plots displayed a similar extent of CO₂ removal for both the amended and reference catchments, but the third amended catchment had a higher extent of CO₂ removal (4.5^-0.2_+0.1 tCO₂ ha^-1) relative to its adjacent reference catchment (3.5^-0.2_+0.1 tCO₂ ha^-1). The ~1 tCO₂ ha^-1 difference in CO₂ removal rates determined for this catchment pair can likely be attributed to increased weathering of silicate minerals in the amended catchment and is similar to the value predicted by reactive transport modelling. Soil carbonate concentrations were low (on average < 0.2 wt% CaCO₃) but we measured a significant increase in the amended catchments relative to the reference catchments (by ~0.03 wt% in the top 30 cm of soil) since the crushed silicate rock was first applied. The magnitude of CO₂ drawdown via alkalinity export and carbonate precipitation determined for these agricultural catchments is around an order of magnitude higher than in natural forested catchments in Sabah. 

One postulated co-benefit of amending highly acidic degraded tropical soils typical of oil palm plantations with crushed basalt is that the resulting soil pH increase improves nutrient uptake by palm roots to potentially increase production. Statistical analyses of the yield data collected over 4 years from the treated and control catchments and smaller plots are now showing a significant (P < 0.05) increase in oil palm yields resulting from increased bunch numbers per palm and an increase in bunch weight by up to 10% (see graph below). These results support our original hypothesis and are being followed up by detailed analyses of leaf tissue chemistry and ongoing collection of yield data.

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2022-2023

Basalt was first applied to young oil palms on a plantation in Sabah, Malaysian Borneo, in 2018. The palms first began to fruit in mid-July 2020 and the early effects of basalt application on oil palm yield can now be assessed. Analysis of 936 palms (468 treated with basalt and 468 “control” palms that were not treated) indicated a significant difference in the number of fruit bunches per palm between palms that were treated with basalt versus those that were not since the palms began to fruit (see graph below). 

Number of fruit bunches per palm in control and basalt-treated sites in Sabahmas Plantations Sdn. Bhd., Lahad Datu, Sabah Malaysia. In nearly every harvest, the quantity of fruit bunches produced per palm on basalt-treated areas was significantly higher than on control sites. Error bars represent the standard error of the number of bunches per palm.

Basalt-treated palms recorded a significantly higher number of bunches per palm than control sites (0.618±0.002 bunch/palm and 0.559±0.002 bunch/palm, respectively). Similarly, log total bunch weight per palm also showed a significant difference between treatments (see graph below), where palms treated with basalt had a higher log total bunch weight per palm compared to control sites (2.208±0.001 and 2.160±0.0.001 respectively). An average yield differential of 0.2±0.07 tonne ha^-1 per harvest was seen when basalt was applied at a rate of 50 tonne ha^-1 per year, with basalt-treated sites outperforming control sites in terms of yield. As the oil palms have not yet reached optimum yield (which typically occurs 12-13 years after transplanting), the fruit bunch yield can be expected to increase in future years.

Error bars represent the standard error of log total bunch weight per palm.

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2023-2024

The performance of carbon dioxide removal (CDR) technologies across Global South regions vulnerable to climate change is poorly understood. Initial assessment of our field trial data so far indicates that amending soils annually with a coarse crushed basalt (50 t ha^-1 yr^-1) over five years drives 67% dissolution of the basaltic minerals leading to a cumulative CDR potential of 32 ± 3 t CO₂ ha^-1 yr^-1. This is three-fold higher than observed in a temperate US Corn Belt EW field trial with the same application rate and likely reflects the warmer wetter sub-tropical climate of Malaysia.

Our operations at this important EW field trial site continue.  We have now applied 1,257 tonnes of basalt to the oil palm plantation of Sabahmas Plantations Sdn. Bhd. in Sabah, Malaysian Borneo, from August 2018 to November 2023. Visual Evaluation of Soil Structure (VESS) scores conducted in 2022, 2023, and 2024 revealed consistent significant improvements in soil condition (t_0.05,28 = 5.67, p<0.001; see below), where basalt-treated sites had better soil structure compared to untreated sites (3.43±0.23 and 4.83±0.1, respectively). Sites treated with basalt have a higher soil pH compared to untreated sites, for the soil below the palm (5.5 ± 0.09 and 5.0 ± 0.06, respectively) and the soil between the palms (5.3 ± 0.08 and 5.0 ± 0.06, respectively). 

Provisional analysis of our data collected indicate that between 2021 and 2024, palm oil yields increased significantly by 10-25 % per month on the basalt-treated sites (see below). In terms of revenue increase, this amounts to $100-$260 gain annually following EW treatment with basalt and discounts the cost of undertaking EW operations substantially. As the oil palms continue to grow, yields rise in subsequent years (usually peaking 12-13 years after transplanting), during which we will continue to assess basalt treatment effects on yield.

In June 2023, we conducted a series of five day-long deliberative workshops with residents across five different locations in Malaysia (see below). Three workshops were held in Kota Kinabalu, the capital city of Sabah, involving two groups of randomly recruited members of the public and one group of specialists (e.g. NGOs, civil servants). Two further workshops took place in Lahad Datu town and the rural village of Kampung Tampenau, which were selected due to Lahad Datu's significance as one of the largest oil palm plantation landscapes in Sabah.

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2024-2025 

In the third quarter of 2024, we sampled soil in both basalt-treated and control sites before another round of basalt application. The basalt was applied for the 7^th time at the rate of 30 tonnes per hectare, a reduction of 20 tonnes per hectare from the previous rate. Analysis of the oil extraction ratio of palm fruits harvested in November 2024 shows that oil palm treated with basalt continues to outperform oil palms from the control sites (24.03±1.08% for basalt-treated palms vs 21.55±1.27% for control palms). In addition to regular water sampling, oil palm observations and fresh fruit bunch census, further visual evaluations of soil structure and analyses of the oil extraction ratio will be conducted in the second quarter of 2025.

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Papers featuring our Malaysia field trials

Cox, E., Lim, R., Spence, E., Payne, M., Beerling, D. & Pidgeon, N.F. et al (2025) Question-led innovation: public priorities for enhanced weathering research in Malaysia. Environmental Science and Policy, 163, 103977. https://doi.org/10.1016/j.envsci.2024.103977 Published 31 December 2024

Abd Aziz, A., Nor Ghani, A., Sugiyama, M., del Barrio Alvarez, D., Cox, E., Spence, E. & Kamaludin, M. (2024). Public perception of Carbon Dioxide Removal (CDR) and its influencing factors: Evidence from a survey in Malaysia. Sustainability Science. http://dx.doi.org/10.1007/s11625-024-01587-2 Published 26 November 2024. 

Hilser, H., Cox, E., Moreau, C., Hiraldo, L., Draiby, A., Winks, L., Andrews, M.G. & Walworth, N.G. (2024) Localized governance of carbon dioxide removal in small island developing states, Environmental Development, Volume 49, 2024,100942, https://doi.org/10.1016/j.envdev.2023.100942. Published 30 November 2023.

Kemp, S. J., Lewis, A. L., and Rushton, J. C. (2022) Detection and quantification of low levels of carbonate mineral species using thermogravimetric-mass spectrometry to validate CO2 drawdown via enhanced rock weathering. Applied Geochemistry, 146, https://doi.org/10.1016/j.apgeochem.2021.105023. Published 18 September 2022.

Larkin, C.S., Andrews, M.G., Pearce, C.R., Yeong, K.L., Beerling, D.J., Bellamy, J., Benedick, S., Freckleton, R.P., Goring-Harford, H., Sadekar, S. & James, R.H. (2022) Quantification of CO₂ removal in a large-scale enhanced weathering field trial on an oil palm plantation in Sabah Malaysia.  Frontiers  limate, 4, https://doi.org/10.3389/fclim.2022.959229. Published 30 August 2022.

Epihov, D. Z., Saltonstall, K., Batterman, S. A., Hedin, L. O., Hall, J. S., van Breugel, M., Leake, J. R. & Beerling, D. J. (2021) Legume-microbiome interactions unlock mineral nutrients in regrowing tropical forests. Proceedings of the National Academy of Sciences, USA, 118, e2022241118. https://doi.org/10.1073/pnas.2022241118. Published 16 March 2021.

Beerling, D. J., Kantzas, E., Lomas, M. R., Wade, P., Eufrasio, R. M., Renforth, P., Quirk, J., Sarkar, B., Andrews, G., James, R. H., Pearce, C. R., Khanna, M., Koh, L., Quegan, S., Pidgeon, N. F., Janssens, I., Hansen, J. & Banwart, S. A. (2020) Potential for large-scale CO₂ removal via enhanced rock weathering with croplands. Nature, 583, 242-248. https://doi.org/10.1038/s41586-020-2448-9. Published 8 July 2020.

Kelland, M.E., Wade, P.W., Lewis, A.L., Taylor, L.L., Sarkar, B., Andrews, M.G., Lomas, M.R., Cotton, T.E.A., Kemp, S.J., James, R.H., Pearce, C.R., Hartley, S.E., Hodson, M.E., Leake, J.R., Banwart, S.A. & Beerling, D.J. (2020) Increased yield and CO₂ sequestration potential with the C₄ cereal Sorghum bicolor cultivated in basaltic rock dust amended agricultural soil. Global Change Biology, 26, 3658–3676. https://doi.org/10.1111/gcb.15089. Published 21 April 2020.

Edwards, D.P., Lim, F., James, R.H., Pearce, C.R., Scholes, J., Freckleton, R.P. & Beerling, D.J. (2017) Climate change mitigation: potential benefits and pitfalls of enhanced rock weathering in tropical agriculture. Biology Letters, 13, 20160715. https://doi.org/10.1098/rsbl.2016.0715. Published 5 April 2017 as part of the mini-series “Enhanced rock weathering: biological climate change mitigation with co-benefits for food security”.

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Stay tuned for our final update instalment next year!