Perspective Chapter: Oil Palm Plantations Can Offset Carbon Loss and Improve Livelihoods of Rural Communities in Africa

1. Introduction

Global efforts are underway to establish CO₂ mitigation policy amid uncertainty about the deeper economic consequences of its actions. Common wisdom currently holds that palm oil producers should not be considered as viable candidates for carbon offset credits because their plantations historically result from the conversion of tropical forests. This position may not be tenable, particularly in Africa, where plantations were established many decades ago and now drive local economies. Bokanga [1] describes the importance of oil palm (Elaeis guineensis Jacq.) in the Democratic Republic of Congo (DRC) and argues that, if responsibly developed, the palm oil industry could lift millions of people out of poverty. With its plentiful humid land, abundant labor, favorable climate and reliable market demand, the DRC is poised to become the next frontier for palm oil, but in a way that learns from past mistakes made in Asia and elsewhere, ensuring human prosperity, social progress and environmental protection. An important component of this future is the award of carbon credits for its carefully informed efforts and then the use of these credits for improvements in the social welfare of communities living within oil palm-forest ecosystems.

Planned development of oil palm expansion in South America provides a useful example in terms of sustainable development. Over the past decade, new plantations have increasingly avoided deforestation and are guided by roundtable certification programs [2, 3]. Strategies are also being adopted to expand oil palm coverage in Indonesia and Malaysia in ways that avoid deforestation and peat soils [4, 5]. Substantial growth of the palm oil industry is expected in Africa and there is commitment to achieve such growth in a manner that improves livelihoods and protects natural resources, including forests [1]. Numerous countries of West and Central Africa signed the Marrakech Declaration for Sustainable Development of the Palm Oil Sector in 2016 during COP-22 in which they commit to sustainable development of the palm oil value chain. This effort was reinforced through the African Palm Oil Initiative, followed by the Africa Sustainable Commodities Initiative, where these countries commit to zero deforestation [6]. Within the DRC alone, the Ministry of Agriculture identified over 2000 abandoned farms, many of which can be put into palm oil production at no risk to primary forests [7]. More expansive goals toward a sustainable palm oil industry are now directed through participation in the Roundtable on Sustainable Palm Oil (RSPO) [8, 9].

The main environmental concern related to the palm oil industry is deforestation and its effect on habitat loss and the release of system carbon into the atmosphere. Secondary impacts include pollution of local surface waters and excessive use of mineral fertilizers and pesticides. In response, the industry established the RSPO certification program [8] to ensure that palm oil has a positive impact on the planet and on people. Stakeholders engaged in this effort include oil palm producers, processors and traders, as well as manufacturers, investors, environmental conservation groups and an assortment of Non-Governmental Organizations. It is notable that oil palm plantations and mill managers are increasingly adopting practices that reduce negative environmental impacts [10] through site-specific nutrient balance management, biological control of pests and establishment of leguminous cover crops, particularly Mucuna and Pueraria spp. [11].

When evaluating the importance of oil palm, we must consider that this tree crop yields 5–10 times more oil per hectare per year than annual oil crops. In this way, oil palm occupies less than 10% of the land planted with oil crops but produces more than 35% of the oil consumed worldwide [12]. Oil palm requires less land, pesticides and fertilizers and provides income to some of the world’s poorest countries. Yet oil palm remains criticized for its negative impact on GHG emissions in ways that tend to exclude it from the award of carbon credits. We contend that this situation requires reevaluation.

2. The controversy surrounding oil palm

Oil palm plantations have a very poor reputation, but much of this disdain is likely undeserved. Oil palm plantations are viewed as major drivers of tropical deforestation that leads to massive emissions of C into the atmosphere. Moreover, it has been estimated that, given the current carbon credit system, converting forests to palm oil production was much more profitable than conserving forests for carbon credits [13], which could potentially drive additional rounds of forest loss. Germer and Sauerborn [14] estimated the impact of oil palm plantation establishment on system C balances through both forest and grassland conversion. Forest conversion on mineral soils resulted in losses of 177 t C per ha and considerably more in peat soil. In contrast, conversion of tropical grassland to oil palm resulted in 36 t C ha⁻¹ gains in system C. Hashim et al. [15] confirmed the vulnerability of C loss from peat soils converted to oil palm production, estimating losses as great as 77 t CO₂ eq ha⁻¹ depending upon the depth of the peat deposit and the amount of nitrogen fertilizer applied over time. In the Kalimantan region of Indonesia, oil palm expanded by 278% from 2000 to 2010, with 90% of these lands derived from intact forests (47%), logged areas (22%) and agroforests (21%). Ominously, 79% of Indonesia’s allocated leases for conversion to oil palm remained undeveloped as of 2010 [16]. The full development of these leases, which cover 93,844 km² (90% forested lands, including 31% intact forests), would contribute 18–20% (0.12–0.15 GtC yr⁻¹) of Indonesia’s 2020 CO₂-equivalent emissions.

Expansion of oil palm cultivation into African humid forests could lead to large carbon emissions. In Gabon, the conversion of 11,500 ha of logged forest into oil palm plantations is expected to release about 1.50 Tg C. However, Burton et al. [17] have estimated that these emissions could be offset over 25 years through sequestration in the planned forest set-asides given a 2.6:1 ratio of logged to converted forest. It is important that African land use planners have means to reduce these expected environmental impacts through a better understanding of system C stocks and incentives offered for their better management. Using original forests as a reference point, numerous ecosystem functions are lost in oil palm plantations including those with global impacts such as carbon storage, habitat loss and incompletely described and preserved genetic and medical resources [18]. One function that increases greatly within palm plantations is the generation of economic value. Fitzherbert et al. [19] assert that oil palm plantations support much fewer species than do forests, and less than other tropical tree crops, concluding that substantial biodiversity losses can only be averted by assuring future oil palm expansion avoids direct deforestation [20].

3. Oil palm carbon stocks and sequestration

Forest and oil palm biomass were compared in Indonesia by Kotowska et al. [21]. Total tree biomass in natural forests averaged 384 Mg ha⁻¹ and was over seven times greater than average oil palm plantation biomass (50 Mg ha⁻¹). However, Net Primary Productivity was higher in the oil palm system (33 Mg ha⁻¹ yr⁻¹) than in the natural forest (24 Mg ha⁻¹ yr⁻¹), in large part because of massive offtake from fruit production (15–20 Mg ha⁻¹ yr⁻¹). Oil palms compete less with one another and receive the benefits of soil and pest management, and in this way, their potential to sequester C in the short term may be greater than that of forests. Total system carbon in an oil palm plantation in eastern Amazonia was estimated to hold 99.1 ± 3.1 Mg C per ha including 2.3 ± 0.1 Mg C ha⁻¹ of litter [22]. The total dry biomass in another 25-year-old Brazilian plantation contained 90 Mg ha⁻¹ [23]. An oil palm plantation accumulated 112 Mg ha⁻¹ aboveground biomass that sequestered 3.7 Mg C ha⁻¹ yr⁻¹ after 10 years in northeast India [24]. Citing many sources from Indonesia, the Palm Oil Agribusiness Strategic Policy Institute [25] suggests that the carbon stocks of oil palm plantations range from 30 Mg C to 75 Mg C ha⁻¹, with a mean of about 40 Mg C ha⁻¹ in an average-aged plantation. From these examples, a strong pattern is emerging across diverse locations.

A detailed C budget of oil palm involving plant biomass, litter and soil, also reported high rate of carbon sequestration by oil palm ecosystems, between 2.5 and 9.4 Mg ha⁻¹ yr⁻¹, including harvested bunches [26]. Similar findings were reported by Lewis et al. [27] who recorded aboveground biomass accumulation in Malaysia of 6.4 Mg ha⁻¹ yr⁻¹ during the first 12 years after planting, and 8.0 Mg ha⁻¹ yr⁻¹ thereafter. Research from the Philippines reports that a 9-year old oil palm plantation sequestered 6.1 Mg C ha⁻¹ yr⁻¹, with total C stocks of 55 Mg C ha⁻¹ [28]. Note how these findings fall into general agreement, particularly the rates of annual sequestration. Clearly, the oil palm has major potential for atmospheric CO₂ sequestration over the short term, a factor that must be better appreciated in judging its larger environmental impacts.

Oil palm plantations should be eligible for accrued carbon credits under some strict conditions. Carbon debt results when the vegetation removed to establish crops have a greater C stock than the resulting managed system. In a study of 25 oil palm plantations in Indonesia, the average aboveground C stock of a 25-year rotation was 42 Mg C ha⁻¹ on mineral soils and 40 Mg C ha⁻¹ on peat soils. In contrast, in Chiapas, Mexico, a 12-year-old oil palm plantation accumulated 878 kg biomass C per palm, or 126 t C ha⁻¹ in a stand of 143 palms ha⁻¹ [29], suggesting that large variability exists between plantations and areas. Henson et al. [30, 31] stated that where lands converted to oil palm have reduced biomass, plantations can lead to increased carbon stocks. In this case, emissions from land use change are reduced compared to other sources of greenhouse gasses from mills, fossil fuels and fertilizers. From this, we conclude that plantations must not be recently carved from humid forests as the comparative carbon stocks remain unfavorable into the foreseeable future. Plantations also must not be established on peat soils as the long-term dynamic of soil organic matter is strongly negative and complicates carbon accounting. However, longstanding plantations or those established on the mineral soils of grassland and landscapes degraded by previous human activities offer a strong potential to accumulate system carbon over decades.

Henson et al. [32] described the importance of including frond bases within estimates of palm biomass and system carbon stocks of the oil palm. These frond bases remain attached to the trunk after frond pruning. Estimates of C stocks in Papua New Guinea were increased by 11% after taking frond bases into account. Soil C increases were documented in Brazilian oil palm plantations [33]. Soil C stocks were higher adjacent to the oil palm base and beneath frond piles compared to access pathways. In some cases, a soil organic C increase of 25% was observed compared to soils under native vegetation, indicating a substantial gain of soil C stocks in oil palm plantations over time.

4. Better managing oil palm plantation carbon

Reliable and efficient methods to monitor system carbon gains are available. Oil palm biomass is primarily a product of its’ combined root, trunk and frond biomass, with an additional value assigned to its fruit removal [34]. Determining the capacity of oil palm to sequester carbon requires accurate biomass estimates based upon destructive sampling that is used to develop and test allometric equations, as was performed in Gabon by Migolet et al. [35]. Stems accounted for 73% of total aboveground biomass, rachises for 13%, petioles for 8% and fruits and leaflets for 6%. Roots are assumed to hold about 30% of the total biomass. The best allometric equations incorporate Diameter at Breast Height (DBH), stem height, tissue density and leaf number, although the latter two parameters are more difficult to measure. A simpler model relying upon DBH and height accounted for 93% of observed aboveground biomass.

Established relationships also exist between canopy size and aboveground biomass, with both crown diameter and crown area serving as proxy variables [36]. An even simpler allometric equation developed in Mexico considers only oil palm height using the equation Biomass = 98.349 Height + 737.41 (R2 = 0.577) [37]. Allometric equations are also available to calculate the average dry weight of mature fronds as a means of estimating annual production of oil palm frond biomass and their contribution to plantation system carbon stocks [38]. While it is not the purpose of this paper to compare different allometric approaches and equations, it is important to note that such tested equations are widely available in the published literature.

Several plantation management practices lead to increased carbon stocks within oil palm plantations. The upper limits of this accrual are manageable based on the handling of crop residues and accompanying vegetation and basic soil conservation measures. Plantation management measures prevent or reduce the loss of ecosystem functions by avoiding further land clearing and burning, avoiding peat soils, relying upon integrated pest management and introducing of cover crops, mulching and composting [18]. Carbon-smart management of oil palm residues suggests that they are best returned as mulch for more efficient C and nutrient cycling. Leaf biomass pruned from oil palm and applied as mulch steadily decomposes to provide a source of organic matter and nutrients. During 2 years of decomposition, fronds and leaflets lost 88% and 86% of their initial weight and released 51% and 83% of their nitrogen, while also releasing 87% and 93% of phosphorus, respectively [39]. Oil palm readily recycles its nutrients.

Residue retention as a part of management practice allowed for increased soil organic carbon stocks within oil palm plantations in Sumatra, Indonesia. Soil carbon stocks increased by 11 t C ha⁻¹ when alternate interrows received enriched mulch and fronds compared to the adjacent unmulched harvesting path [40]. This adjustment allows for access to the fruit bunches while more effectively recycling organic residues, but it must be balanced with the advantages of field sanitation and safety. Indeed, sequestration of soil carbon in these plantations can be a key component to reverse system carbon losses.

Guidelines were established to reduce greenhouse gas emissions from oil palm plantations in Colombia. Suggested practices include increasing the use of organic fertilizers, planting oil palms on degraded land, using oil palm biodiesel as a substitute for fossil fuels, improving the yield of oil palm fresh fruit bunches through increased production efficiency and producing and applying biochar at the time of replanting [41]. It was also calculated that each ton of oil palm fresh fruit bunches resulted in the fixation of 606 kg of CO₂.

5. Alternate pathways for mitigation

There is also the possibility to reduce carbon emissions through improved management of the palm oil mills associated with these plantations. Palm oil processing also leads to greenhouse gas emissions. Hong [42] suggests that a typical mill produces emissions of 637 to 1131 kg CO₂ eq per ton of crude palm oil (CPO) produced and the need exists to reduce this footprint. Capturing biogas from mill effluent, converting palm sludge oil into biodiesel and briquetting biomass to serve as a substitute for fuelwood can reduce these emissions by 457 kg CO₂ eq per ton of CPO. Efforts to redesign mill operations in Thailand demonstrate how the integrated utilization of oil palm biomass has great potential to reduce carbon emissions, with savings of 812 kg CO₂ eq per ton of CPO [43, 44]. In Colombia, 58% of mill emissions originate from anaerobic ponds used for water treatment, 41% from powering mill operations and only 1% from transportation and heavy machinery [45], and corrective measures focus on those first two sources. Indeed, capturing emissions from mill effluent and reducing dependence upon fossil fuels are the two prominent mechanisms for GHG reduction within milling operations [46].

Durable carbon removal of oil palm waste can also be achieved through biochar production via thermochemical conversion under no or limited oxygen. The fixed carbon content of biochar and properties relevant for soil health improvement depend on the type of oil palm waste, temperature profile and airflow during processing [47]. Fronds converted at 500°C over 30 minutes produced 40% porous biochar with a calorific value of 22.6 MJ kg⁻¹ [48]. Empty fruit bunches offer a particularly suitable candidate for biochar, as shown in SE Asia [49]. There are two major processes for biochar production, often confused but critically different: pyrolysis and gasification. Pyrolysis occurs in the absence of oxygen, relying on external heat from a combustion furnace. This process typically operates at temperatures between 300°C and 600°C. Gasification admits small amounts of oxygen and does not require external combustion. This process usually operates at temperatures ranging from 450°C to 1500°C. Attention must be paid to the differences between the processes since they lead to variable outcomes in carbon balance and biochar characteristics.

A wide range of technologies exists to produce biochar that serves various energy applications. These include domestic cookstoves, simple kilns, rapid food dryers and electricity and heat generators. Artisanal or automated kiln systems can be employed for local in-field production, including continuous flow containerized and cottage-style setups that capture heat for value-addition processes. Recovery of biochar from biomass input for these systems is typically 25–30%, and output capacity ranges from 200 kg to 2.4 ton biochar per batch. Existing gasification setups are self-contained and convert up to 1 ton of dry biomass feedstock into 1 megawatt hour (MWh) of electricity, 1.2 MWh of heat and 100–150 kg of biochar. Each MWh of electricity produced by gasification can replace 400 liters of diesel. Overall, pyrolysis and gasification have fundamental advantages over biomass combustion as an energy source by realizing higher energy efficiency and the ability to operate fully upon low-grade residues obtained from oil palm plantations.

The use of locally available biomass for biochar and the potential for remote production can stimulate rural economies and create jobs. In Malaysia, pyrolysis of oil palm waste has attained commercialization and gasification is being piloted [50]. In comparison, agribusinesses are implementing similar operations within coffee mills in Brazil and rice mills in Thailand. Unit costs of biochar production depend upon logistics, energy utilization and available carbon credits. Costs are lowest when biomass is sourced within less than 10–20 kilometers and when the project is accredited for high-quality carbon credits with minimal administrative overheads for monitoring, reporting and verification.

While biochar may be pressed into briquettes for use as solid fuel, it is often better utilized in other applications. These include serving as an absorbent in chemical processes, a conditioner in compost or manure treatment, a soil amendment in plantations and a potting substrate in nurseries. Harson et al. [51] examined biochar production from palm oil empty fruit bunches in Malaysia. The energy yield from slow pyrolysis was positive, resulting in about 11 MJ kg⁻¹ of product, calculating that biochar production costs were $533 t⁻¹. When subjected to microwave pyrolysis, oil palm wastes produced a biochar with many desirable properties that may be used as a biofuel with high heating value (23–26 MJ/kg), an environmentally friendly adsorbent of contaminants, and as a carbon sequestering soil amendment and biofertilizer [52]. Razali and Kamarulzaman [53] contend that biochar produced from the palm oil trunk is suitable for the absorption of pollutants within mill wastewater effluent. These results suggest that oil palm waste is better transformed into biochar than simply disposed or burned as a low-grade fuel.

Kong et al. [54] reviewed the potential and challenges of producing biochar from oil palm biomass, concluding that biochar leads to a healthier environment and societal and economic growth for the oil palm industry, as well as benefiting global sustainability interests. Oil palm seedlings raised on potting mixture with 3% w/w biochar from empty fruit bunches resulted in 23% faster growth in the first year compared to when fertilizer alone is used [55]. Long-term research trials in annual cropping systems of Kenya found decade-long increases in yield and fertilizer use efficiency from a single biochar application [56]. The use of biochar is becoming commonplace in coffee agribusiness across the Global South, with producers in Brazil and Tanzania applying it since 2011.

When produced under the right conditions, biochar removes carbon from the atmosphere for hundreds of years [57]. In 2023, biochar was leading the delivery of carbon removal among all strategies, favored by credit markets due to affordability, permanence, ease of certification, scalability and benefits to communities. Robust chain-of-custody application is available for artisanal production that tracks all steps of the process from sourcing to conversion and sinking. Projects with combined biochar and energy production may need to invest in the development of integrated data management systems for streamlining the quantification of offsets and removals at various levels of operation. Biochar is currently not yet recognized as a soil input by the government of the Democratic Republic of Congo (DRC). However, its use has been recommended by local experts [58] and has been confirmed as effective in improving water retention in soils [59]. Various international organizations have established quality standards for biochar, focusing on aspects such as carbon content, nutrient levels and limits on heavy metals and organic contaminants. These standards differ based on the intended application of biochar, whether as a soil amendment, energy source, or building material.

6. Carbon credit qualification and associated risks

Any carbon credits awarded to palm oil producers in Africa should be in full compliance with the principles and criteria of the Roundtable on Sustainable Palm Oil [8, 9]. RSPO is a multi-stakeholder organization that guides the palm oil industry toward environmentally sound and socially equitable outcomes. It offers comprehensive standards and procedures that support climate security. RSPO requires members to understand system carbon stocks and prohibits planting in forests and on peat soils. It also works with members to calculate emissions risk profiles of processing facilities. It offers a reasonable balance between environmental protection and economic development and estimates that its guidance avoids the release of 2.2 million MT of CO₂ eq yr⁻¹ [9].

Before credits for carbon removal through palm oil waste management are sold, the supplying entity must demonstrate compliance with criteria on baselines, additionality, quantification and monitoring, permanence and avoidance of double accounting. These are governed through protocols from carbon registries that are internationally accredited for carbon offset projects to document and validate project design and monitor periodic reports. Independent rating agencies can also score projects based upon various factors related to planned environmental and social impacts. In this way, levels of supervision also affect the assigned price per unit of GHG removal.

There may be issues with additionality, as projects must demonstrate that carbon removal would not have taken place without key policy and tax incentives, or without credit revenue. Additionality is determined by assessing whether the proposed project is distinct from its baseline scenario. This may form another challenge as projects must have historical data on land expansion and tree cover loss, but its requirement forces plantations to better monitor their environmental impacts over time.

7. The case for PHC as an eligible C offset provider

Plantations et Huileries du Congo (PHC) is the largest industrial producer of palm oil in the Democratic Republic of the Congo (DRC). PHC’s headquarters are located in Kinshasa, but its plantations are located deep within the Congo Basin at Lokutu (Tshopo Province), Yaligimba (Mongala Province) and Boteka (Equateur Province). The company manages over 100,000 hectares of land within its concession. Oil palm occupies 28% of this concession, while 24% is adjacent forests of high conservation value. Fallows and degraded forests cover 46% of the concession, while mills, offices, housing and roads occupy the remaining 2%. Established in the 1910s, Boteka is PHC’s smallest and oldest plantation. The Yaligimba and Lokutu plantations were established in the 1920s and 1930s, respectively. Each plantation hosts a palm oil mill that is powered by a turbine, obtaining energy from a boiler that burns biomass from plantation harvests. The boiler also produces steam that is used during the processing of oil palm’s fresh fruit bunches. The mesocarp of the oil palm fruit provides crude palm oil (CPO). In a separate process, the kernel of the oil palm fruit is obtained and cracked to release its nut, which is pressed to extract a second type of oil, the palm kernel oil (PKO). No chemicals are used in the production of palm oil. In 2023, PHC managed mature oil palms covering about 21,400 hectares.

A projection based upon data from this paper and information on production and mill practices suggests that the 21,400 ha under oil palm production sequester 76,397 ± 3777 tons of system carbon per ha per year. This is equal to 280,124 ± 13,847 tons of CO₂ eq that could be worth US $1,400,618 ± 69,236 per year, at $5 per ton CO₂ eq, if a buyer could be found (Table 1). This projection assumes a 25-year rotation starting with 140 palms per ha and an attrition of 0.5 plant ha⁻¹ yr⁻¹. It also assumes an equal division of age classes over the 25-year rotation, where 856 ha of land is replanted each year. A projection of plantation carbon over a 25-year rotation appears in Figure 1. This estimate does not consider soil organic C, does not separate leaf and fruit C over time and requires further verification within each plantation in the future.

It is likely that the greatest environmental benefits are obtained as the result of producing biochar from the oil palm’s empty fruit bunches and then returning the product to the plantation’s soils. PHC collects about 70,000 tons of these empty fruit bunches from its mills per year (Table 2) and transports them back to the plantation. Converting them to biochar at 17.5% biochar yield, the equivalent of 12,250 tons of biochar could be obtained. Applying this biochar to annually replanted lands (858 ha yr⁻¹) would contribute 14.3 tons of biochar per ha, or 102 kg of biochar per palm. If the same quantity of biochar were to be spread across the entire plantation, each ha would receive 0.57 t yr⁻¹, equivalent to 4.4 kg of biochar per palm. It is not yet determined which scheme would be most practical and profitable, but evidence suggests that biochar addition also improves the use efficiency of applied mineral fertilizers.

The paper also explores how a carbon credit program for the three extensive plantations of PHC Ltd. in DRC could be structured. The revenues generated from plantation offset payments are best directed toward the communities living around plantation activities and toward the protection of the adjacent natural habitat. Climate financing directs funds in support of mitigating climate change and requires that land managers adopt a suite of monitored practices aimed at supporting efforts to mitigate and adapt to climate change. It involves financial instruments such as grants, concessional loans, equity investments and guarantees. When used as a financing mechanism for carbon management by large, tropical plantations, it catalyzes innovation that advances more sustainable agricultural practices and technologies that in turn sequester additional, more predictable quantities of system C into the future. In the case of PHC and its plantations in the Congo Basin, this financing would promote climate-smart plantation practices by the company and climate-smart agricultural production systems to be adopted by surrounding communities, facilitate data collection and analysis of oil palm systems and adjacent natural forests, foster markets and payments for expanded ecosystem services and more fully align DRC with the priorities and criteria of climate finance institutions as a means of achieving its climate agreement targets. Several risks associated with carbon offsets involving palm oil producers and possible responses appear in Table 3.

Awarding C credits to PHC can also protect the biodiversity of the forests within and adjacent to its concessions. Presently, the loss of natural forest is not occurring as a direct result of plantation practices, but forest disturbance is caused by the slash-and-burn farming practices of local communities in their quest to produce food crops. In addition, illegal logging of Pericopsis elata, an endangered species and Afzelia africana, a vulnerable species, is ongoing [60]. Swamp forests are common in the area and two of the concessions (Boteka and Lokutu) have highly fragmented plantations because oil palm is not suited to their waterlogged soils. The resulting fragmentation requires that wildlife corridors be established and maintained. At the same time, there are several invasive plant species present in and around the plantations including Canna indica, Mimosa pigra, Chromolaena oderata and Alchornia cordifolia [60]. Funds from carbon credits could be directed in part toward their removal. A plan for the control of illegal logging would also be put into effect. Finally, PHC’s ongoing community development initiatives will increase household food supply and reduce the need to clear additional forests.

The southern bank of the Congo River, where the Boteka and Lokutu concessions operate, is also the habitat of the great ape Pan paniscus, better known under the common name “bonobo.” This endangered species is the closest relative of the human species and is only found in this part of the DRC [61]. Its survival is threatened by poachers and the slash-and-burn agriculture that disturbs its habitat. PHC provides support to a project for the protection of the bonobo to prevent its hunting, to offer alternatives to slash-and-burn agriculture and to provide sustainable livelihoods to the indigenous communities that share the bonobo habitat. Resources from carbon credits will strengthen these efforts and provide incentives for additional conservation measures, including through mobilizing supportive community actions.

To its credit, PHC has pledged to promote environmental management systems that are sustainable, minimize environmental degradation and protect forests and habitats along its margins. This approach offers a win-win strategy as it also reduces production costs and increases profitability. Previous plantation practices may have contributed to GHG emissions but that was decades before this impact was widely understood. Sustainable plantation management also avoids soil erosion, nutrient depletion and pollution of surface and groundwater. These approaches to plantation management mitigate climate change by sequestering carbon in the biomass and soil but also improve the resilience of plantations themselves, making them more sustainable into the future. These plantations also generate their own bioenergy to operate mills and power surrounding communities.

In addition, PHC is committed to improving living conditions in rural areas [62]. Through its 4 hospitals and 460 patient beds, PHC provides medical care to more than 150,000 people, including its employees and their families and members of the communities surrounding its operational sites. Between 2021 and 2024, the company has built and equipped 24 primary schools that accommodate more than 7000 children. PHC built and maintains more than 70 boreholes, providing access to drinking water in rural areas. The company also launched PHC Ventures, an initiative to support youth entrepreneurship in the areas of agriculture, health and renewable energy, mentoring young people to realize their business ambitions. PHC has established the PHC Foundation, a not-for-profit public interest institution dedicated to enhancing a positive and sustainable social and economic impact on communities established around its operational sites [63]. Clearly, mechanisms exist for PHC to comprehensively channel revenue from carbon credits toward the local communities that surround its plantations. The eligibility of such plantations can also be factored into national carbon reduction strategies and commitments.

8. Words of caution and potential applications

While this chapter argues in favor of breaking with the past and awarding carbon credits to oil palm plantations that sustainably manage their environmental and social responsibilities in a demonstrable manner [8, 9, 11], we also understand the concerns of those who seek to keep the Congo Basin, and other equatorial forests, in as natural state as possible. These forests are considered the “lungs of the Earth” (along with oceans) and massive carbon sinks [64], and any efforts to encourage those who disturb these systems threatens more idealist world views of tropical ecosystem function.

However, the peculiar situation of the DRC’s component of the Congo Basin needs to be taken into consideration. The main access to the Congo Basin is along the River Congo and its tributaries, especially along its southern shore. Land disturbance penetrates about 50 km or so inland along these rivers, and beyond that are vast Guineo-Congolian humid forests rich in carbon and biodiversity [65]. Due to logistical constraints, palm oil mills need to be located near the Congo River or other major rivers that serve as supply corridors for goods needed for or products coming from industrial operations. Since, for operational efficiency, oil palm plantations need to be located near palm oil mills, it is recommended that sustainable palm oil development policies be limited to within 50 km of the major rivers of the Congo Basin, which is where most degraded forests are in the first place. To many who have never traveled to the Congo Basin, the world seems best served if these forests, their wildlife and inhabitants are protected from any further “disturbance,” however, this non-disturbance may equate to many living in extreme poverty [1].

One may argue that funding oil palm plantations stands in direct contrast to investments that protect and restore nature and may even conflict with past biodiversity agreements [66]. Admittedly, given the limited scope of investment, carbon market funds directed to one sector (e.g., oil palm sequestration and decarbonizing) become less available to others (the protection and restoration of forests). In addition, any further investment in the Congo Basin is likely to improve transportation infrastructure that makes additional forests more accessible and exploitable, and this may be viewed as a leakage from measured carbon gains elsewhere. In this way, the greater appeal of natural forest carbon markets is understandable, and across the DR Congo, there are many forest concessions available for such protection. At the same time, forest carbon markets are subject to credibility issues, and this difficulty discourages investment. On the other hand, the carbon accrued within oil palm plantations is readily accessible and measurable, largely because it exists as a relatively homogeneous overstorey monocrop, based upon a large body of credible science identified in this chapter [27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38]. Verification of performance gains is simply more direct and less costly in oil palm plantations than in natural forests for a host of reasons.

What is lacking in support of oil palm vs. forest carbon in Central Africa are strong counterfactual baselines. Once protected, disturbed lands also accrue system C and reestablish plant and animal biodiversity at relatively high rates as they progress into mature secondary forests. There are too few pairwise comparisons of plantations vs. recovering forests, making it difficult to determine if carbon benefits are being ignored or overstated [18, 19]. On the other hand, less uncertainty exists among carbon market actors engagement with local communities concerning the equitable sharing of carbon benefits. Forest encroachment is by nature a furtive process, and it is difficult to monitor the changed behavior of forest stakeholders, whereas the communities within and surrounding remotely located oil palm plantations are much more organized and approachable, and the plantation itself is well positioned to deliver services that improve stakeholder lives and livelihood [1, 62].

In any event, better-establishing baselines and examining counterfactuals within the Congo Basin are important research priorities in the future. Along these lines, we hypothesize that “as the general public becomes better aware of the improved environmental and social corporate responsibility of Africa’s palm oil producers in the future, carbon investors will consider them increasingly acceptable partners within mitigation strategies,” and this will positively impact upon humanity’s ability to mitigate climate change in a modest, but nonetheless important way into the near future.

9. Conclusions

This paper describes the carbon dynamics of oil palm plantations around the world, with special attention to explaining how oil palm plantations established in Africa for over a century, such as those of the Plantations et Huileries du Congo (PHC) in DR Congo, could qualify as a carbon offset provider. We believe this case is compelling and that much of the current condemnation of the sector is unjustified. The oil palm sector is admittedly controversial based upon a history of negative social and environmental impacts, but it also generates regular income for numerous large- and small-scale growers. The sector has grown more complex in terms of its institutional, social, ecological and environmental dynamics [67]. Recent efforts support the transition to a more sustainable oil palm value chain, with important contributions from both the public and private sectors, and several complementarities have emerged [68]. The greater involvement of civil society organizations strengthens this development.

Oil palm is highly productive and profitable, and worldwide oil demand is rising. At the same time, further oil palm development involves several social and environmental tradeoffs. The crop provides a way out of poverty but also makes communities vulnerable to exploitation [69]. It threatens biological diversity but at the same time potentially offers resources needed to protect adjacent forests. It offers renewable fuel but also threatens to increase global carbon emissions.

Optimizing these tradeoffs in a way that provides local, national and international benefits is the challenge before us. We believe that this challenge can be overcome and that the African palm oil, and the Congo basin in particular, could give rise to a well-regulated and appropriately documented palm oil industry in conformity with science-based criteria prioritizing reduction in carbon emissions and biodiversity conservation. Because of their positions deep within the humid forest zone of DR Congo, meteorological impacts associated with climate change, such as warming trends, changes in rainfall and extreme weather events, are less likely to threaten the viability of oil palm plantations in the Congo basin in the foreseeable future [1, 70]. There will be no substitution of this globally important crop as an adaptive option to climate change; rather, these plantations will continue to accrue biomass at a relatively high and manageable rate, making them potentially important carbon sinks. That many of these plantations were carved from humid forests that contained even more system carbon several decades ago should no longer be pertinent.

Rather, what is today relevant is that (1) this practice of forest conversion is now discouraged and discontinued, (2) management practices that allow for additional carbon storage within plantations are known and utilized and (3) future oil palm plantations are acquired and developed from less productive, disturbed lands rather than carbon-rich forests. The present risk is not the existence of plantations themselves but rather ignoring their potential for greater carbon storage as a mitigative response to the threat of climate change because of historical land management grievances. We cannot ignore the great contribution of oil palm plantations to meeting the social and economic needs of human settlements in the Congo Basin and across the African palm oil belt. Indeed, well-managed oil palm plantations can contribute to progress toward net zero emissions while at the same time uplifting millions of people out of poverty and providing good economic returns to stakeholders.

Acknowledgments

Useful insights into the difficulties in assigning carbon credits to palm oil producers were provided by Chris Okafor of the African Agricultural Leadership Institute. Dries Roobroeck of IITA-Kenya provided insights into biochar production. Plantations et Huileries du Congo (PHC) provided information that allowed for projections appearing in this paper to be generated. Angelique Kajibwami of the PHC Foundation provided information on corporate social responsibility. Discussions leading to the production of this paper were initiated through the DR Congo Agricultural Transformation Agenda, organized by the DRC Office of the President. The International Institute of Tropical Agriculture provided additional support for the development of this paper. The contributions of these individuals and organizations are gratefully acknowledged.