Role of Cashew Cultivation in Mitigating Carbon Emissions in Nigeria's Agri-Food Systems

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Using time-series data spanning 1990–2023, the study analyzes trends in agri-food carbon emissions and evaluates the carbon sequestration potential of cashew plantations based on established agroforestry coefficients. Carbon sequestration was estimated as a function of harvested area and annual sequestration rates, while uncertainty in plantation characteristics was addressed through sensitivity analysis using low, baseline and high sequestration scenarios. The results show that agri-food carbon emissions increased considerably over the study period, driven by agricultural expansion and intensification. Although carbon sequestration from cashew cultivation also increased during periods of area expansion, it remained insufficient to fully offset emissions. On average, cashew-based sequestration contributed about 2.67%, 3.44% and 4.58% of total agri-food emissions under the low, baseline and high scenarios, respectively, with peak contributions reaching approximately 9.85%, 12.70% and 16.93%. These findings suggest that while cashew cultivation represents a significant carbon sink, its mitigation potential is constrained when considered independently of broader emission reduction efforts. The study concludes that cashew cultivation can play a complementary role in climate change mitigation within Nigeria's agri-food sector. Expanding cashew production, particularly on degraded lands and promoting climate-smart land management practices can enhance carbon sequestration while supporting rural livelihoods. However, achieving substantial emission reductions will require integrated strategies that combine sequestration with measures to reduce emission intensity across the agri-food system. Carbon sequestration values are modeled estimates derived from area-weighted coefficients based on Sub-Saharan African agroforestry literature and therefore represent generalized approximations rather than direct field measurements. Carbon sequestration Cashew cultivation Agri-food emissions Climate change mitigation Agroforestry Nigeria Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 BACKGROUND Climate change poses a major global challenge, with the agri-food sector acting as both a significant source of greenhouse gas (GHG) emissions and a potential pathway for mitigation. Globally, agri-food systems contribute about one-third of anthropogenic emissions, driven by agricultural production, land-use change, and supply chain activities (Crippa et al., 2021; Tubiello et al., 2021). In Nigeria, increasing food demand, population growth, and agricultural expansion have intensified emissions from the sector, raising concerns about sustainability. At the same time, agricultural systems particularly tree-based systems offer opportunities for carbon sequestration. Agroforestry and perennial crops can store substantial carbon in biomass and soils while maintaining productivity (Lal, 2020; Nair et al., 2009). In this context, cashew (Anacardium occidentale), a major export-oriented tree crop in Nigeria, is of growing interest. Beyond its economic importance, cashew cultivation has the potential to function as a carbon sink, with studies in Sub-Saharan Africa reporting significant carbon storage across different plantation ages and management conditions (Bello et al., 2017; Koffi et al., 2025). However, existing research has largely focused on plot-level carbon stocks, with limited evidence linking crop-specific sequestration to national agri-food emission dynamics. This gap is particularly evident in Nigeria, where the mitigation role of tree crops within the agri-food system remains underexplored. This study addresses this gap by examining the role of cashew cultivation in mitigating carbon emissions in Nigeria’s agri-food systems. Specifically, it analyzes emission trends, evaluates the evolution of cashew cultivation, estimates its carbon sequestration potential using established coefficients, and assesses its contribution to offsetting emissions under alternative scenarios. The study provides policy-relevant insights into the role of perennial tree crops in advancing climate-smart and sustainable agricultural systems. INTRODUCTION Agriculture plays a central role in Nigeria’s economy and food system, providing livelihoods for a large share of the rural population while contributing substantially to national output and export earnings. At the same time, the sector represents a major source of greenhouse gas (GHG) emissions, largely through land-use change, deforestation, soil degradation, fertilizer application and energy use along agri-food value chains (FAO, 2023). Greenhouse gases, including carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O), trap heat in the atmosphere, driving global warming and climate change. In agri-food systems, these emissions arise primarily from enteric fermentation in livestock, rice cultivation, synthetic fertilizer use, manure management, biomass burning and land conversion activities that release stored carbon from vegetation and soils (Crippa et al., 2021). Mitigation in agriculture involves practices that reduce net emissions or enhance carbon removal, such as improved nutrient management, agroforestry and the adoption of perennial crops that build long-term carbon stocks in biomass and soils (Kwiatkowski et al., 2023). In Sub-Saharan Africa, agri-food systems are increasingly recognized as both a driver of climate change and a potential entry point for mitigation strategies that align environmental sustainability with rural development goals (Crippa et al., 2021). Africa’s agri-food system contributes a significant share of national emissions, reflecting long-standing challenges related to forest conversion, expansion of cropland into carbon-rich ecosystems and low adoption of climate-smart agricultural practices (Steensland and Zeigler, 2020). While policy attention has largely focused on reducing emissions from fossil fuels and energy use, mitigation opportunities within agriculture particularly those linked to carbon sequestration remain underexplored in empirical economic research. This gap is evident given the country’s commitments under the Paris Agreement and its Nationally Determined Contribution (NDC), which explicitly recognizes agriculture and land use as priority sectors for climate mitigation and adaptation. Perennial tree crops have attracted increasing attention in the climate change literature due to their capacity to sequester carbon in above-ground biomass, below-ground biomass and soils, while simultaneously supporting farm incomes and diversification (Nair et al., 2009; Lal, 2020). Agroforestry and tree-based production systems are widely regarded as effective climate-smart agricultural strategies because they generate long-term carbon sinks and reduce pressure on natural forests by stabilizing land use (Kwiatkowski et al., 2023; Zomer et al., 2016). Advances in crop improvement, including the selection and breeding of high-yielding, drought-tolerant cashew varieties with enhanced root systems and biomass allocation, further amplify this sequestration potential while improving resilience to climate variability (Agboka et al., 2025). However, empirical assessments of the mitigation potential of specific export-oriented tree crops at the national scale remain limited, particularly in African contexts. Agriculture accounts for a large portion of Nigeria’s greenhouse gas emissions, largely due to deforestation, land degradation and methane from livestock and rice farming (Okorie and Lin, 2023). Cashew ( Anacardium occidentale ) has emerged as one of Nigeria’s most important non-oil export crops, with rapidly expanding cultivation across major producing states such as Kogi, Kwara, Oyo, Enugu and Anambra. The crop is well-suited to marginal soils, requires relatively low external inputs compared to annual crops and is typically cultivated as a long-lived perennial system (FAO, 2022). Beyond its economic significance, cashew cultivation has the potential to contribute meaningfully to climate change mitigation by increasing tree cover, enhancing soil organic carbon and substituting for more emission-intensive land-use practices (Nair et al., 2009; Victor et al., 2020). Plant breeding efforts that prioritize varieties with greater biomass production and deeper root architectures can further elevate carbon storage in both above and below-ground compartments (Koffi et al., 2025; Agboka et al., 2025). Despite these attributes, the environmental role of cashew production, particularly its contribution to reducing net carbon emissions from agri-food systems, has received little systematic empirical attention. Notably, no prior study has linked Nigeria-specific cashew harvested area data to national agri-food emission trends, representing a gap this study addresses. Existing studies on agricultural emissions in Nigeria have largely concentrated on livestock systems, fertilizer use, deforestation and aggregate crop production, with limited differentiation across crop types or production systems (Bawa et al., 2023; Suleiman and Anakhu, 2023). Similarly, while the agroforestry literature provides robust evidence on carbon sequestration at plot or farm levels, there is a scarcity of macro-level analyses that link the expansion of specific perennial crops to national agri-food emission trends using consistent time-series data. This gap constrains the ability of policymakers to design crop-specific climate strategies that leverage existing agricultural strengths. Against this backdrop, this study examines the role of cashew cultivation in mitigating carbon emissions within Nigeria’s agri-food systems. Using secondary time-series data from internationally recognized sources, the study analyzes trends in agri-food system emissions alongside the expansion of cashew harvested area and production. It further estimates the carbon sequestration potential of cashew cultivation using established coefficients from the agroforestry and climate change literature, enabling an assessment of the extent to which cashew expansion offsets emissions from the broader agri-food system. Theoretical Framework This study is grounded in three complementary theoretical perspectives: (i) agroforestry and carbon sequestration theory, (ii) land-use change and emissions offset theory and (iii) the climate-smart agriculture (CSA) framework. Together, these perspectives provide a coherent explanation of how the expansion of perennial tree crops such as cashew can influence carbon emissions within agri-food systems. Agroforestry and carbon sequestration theory posits that tree-based agricultural systems act as long-term carbon sinks by storing carbon in above-ground biomass, below-ground biomass and soils (Nair et al., 2009; Lal, 2020). Unlike annual cropping systems, perennial tree crops accumulate carbon over extended periods, resulting in higher carbon residence time and reduced atmospheric CO₂ concentrations. From this perspective, cashew cultivation contributes to climate change mitigation by increasing vegetative carbon stocks and enhancing soil organic carbon, particularly when established on degraded or low-carbon lands (Adjei and Alormu, 2020). Land-use change and emissions offset theory further explains the mitigation role of perennial crops through their capacity to alter land-use trajectories. Expansion of tree crops can reduce emissions by stabilizing land use, limiting repeated soil disturbance and lowering the likelihood of deforestation driven by shifting cultivation or extensive annual cropping (Zomer et al., 2016). In this framework, cashew cultivation functions as a land-use substitute that partially offsets emissions from more carbon-intensive agricultural activities, thereby influencing net emissions at the agri-food system level. The climate-smart agriculture (CSA) framework integrates productivity, adaptation and mitigation objectives, emphasizing practices that simultaneously enhance food security and environmental sustainability (Kabato et al., 2020). Tree-based systems are central to CSA because they combine income generation with ecosystem services, including carbon sequestration and microclimate regulation. Within this framework, cashew cultivation represents a climate-smart pathway through which Nigeria’s agri-food system can contribute to emission mitigation without compromising economic performance. Combining these perspectives, the study hypothesizes that expansion in cashew harvested area is associated with a reduction in net agri-food system carbon emissions through increased carbon sequestration and land-use stabilization effects. Objectives of the Study The main objective of this study is to examine the role of cashew cultivation in mitigating carbon emissions within Nigeria’s agri-food systems. Specifically, the study seeks to: Analyze long-term trends in total and per capita CO₂ emissions from Nigeria’s agri-food systems. Examine the evolution of cashew cultivation in Nigeria, focusing on changes in harvested area and production over time. Estimate the carbon sequestration potential of cashew cultivation in Nigeria using established sequestration coefficients from the agroforestry and climate change literature. Evaluate the relative contribution of cashew sequestration to Nigeria’s agri-food system carbon balance, including sensitivity analysis across scenarios. METHODS Research Design This study adopts a quantitative, time-series research design to examine the role of cashew cultivation in mitigating carbon emissions within Nigeria’s agri-food systems. Consistent with the study objectives, the analysis integrates trend analysis, carbon sequestration accounting and sensitivity scenario analysis using secondary data from various sources. This approach is widely employed in macro-level environmental and agricultural economics studies examining the interaction between land use, agricultural production and carbon emissions (Crippa et al., 2021). Data Sources and Variables Annual data covering the period 1990–2023 are obtained from the following sources: Agri-food system CO₂ emissions (total and per capita), cashew cultivation harvested area (hectares) and production (metric tonnes) from FAOSTAT. FAOSTAT emissions data follow IPCC guidelines and capture emissions from crop production, land use, fertilizer application and related agri-food activities, making them suitable for national-level environmental analysis (FAO, 2022; IPCC, 2019). It is important to note that the FAOSTAT cashew dataset exhibits a sharp discontinuity between 2011 and 2014, during which recorded harvested area fell from approximately 382,000 ha to 126,000 ha. This contraction most likely reflects a revision in FAOSTAT estimation methodology or a change in Nigeria’s national agricultural census reporting rather than an actual collapse in cultivation, though no imputation or smoothing was applied to the raw series in this study; the data are used as reported and this sub-period is identified as carrying elevated uncertainty in all derived sequestration estimates. Furthermore, FAOSTAT aggregates all cashew land as a single national category without age-class distribution; for the purposes of this analysis, the entire cashew harvested area is therefore treated as actively sequestering at the applied coefficient rate, which constitutes a known simplifying assumption. Summary statistics for all key variables are presented in Table 1 . Carbon Sequestration Estimation To address Objectives 3 and 4, the study estimates the carbon sequestration potential of cashew cultivation using a land-area-based accounting approach, consistent with IPCC guidelines and agroforestry literature. Sequestration Formula CS t = CHA t × β where: CSt is the annual amount of CO₂ sequestered (tCO₂/year); CHAt is cashew harvested area (ha); and β is the carbon sequestration coefficient (tCO₂/ha/year). This formulation assumes that the entire harvested cashew area is actively sequestering carbon at a uniform rate and does not account for variation in plantation age structure within Nigeria. Empirical evidence from Sub-Saharan Africa indicates that cashew ( Anacardium occidentale ) plantations accumulate substantial amounts of carbon in both biomass and soils, providing a sound basis for deriving annualized sequestration rates. Field-based studies in West and Central Africa consistently report total ecosystem carbon stocks in cashew systems ranging between approximately 60 and 100 t C ha⁻¹, depending on plantation age, site conditions and management practices (Victor et al., 2021; Agboka et al., 2025; Koffi et al., 2025). For example, Agboka et al. (2025) measured combined biomass and soil carbon stocks exceeding 80 t C ha⁻¹ in ten-year-old cashew plantations in Togo. Chronosequence analyses in Côte d’Ivoire show that total carbon stocks increase with plantation age, from 71.60 ± 6.72 t C ha⁻¹ in young plantations to 82.84 ± 1.21 t C ha⁻¹ in old plantations, equivalent to total CO₂ sequestration ranging from approximately 263 to 305 t CO₂ ha⁻¹ (Koffi et al., 2025). Comparable magnitudes have been reported for cashew plantations in Cameroon, where total carbon stocks (biomass plus soil) typically fall within the 60–97 t C ha⁻¹ range (Victor et al., 2020). Additional studies in Benin report total stocks of 63–85 t C ha⁻¹ across climatic gradients, with higher values in transitional zones (Bello et al., 2017). Applying a conservative annualization approach to the African cashew evidence, annualized rates are derived as follows: for 10-year plantations with ~ 80 t C ha⁻¹, the rate is 8.0 t C ha⁻¹ yr⁻¹ (early establishment phase); for 15-year plantations with ~ 75 t C ha⁻¹, the rate is 5.0 t C ha⁻¹ yr⁻¹ (active growth phase); and for 20–25-year plantations with ~ 85 t C ha⁻¹, the rate is 3.8 t C ha⁻¹ yr⁻¹ (mature stabilization phase). Given that Nigeria’s cashew plantations span multiple age classes and management intensities, this study adopts a moderate baseline sequestration rate of 4.5 t C ha⁻¹ yr⁻¹, equivalent to approximately 16.5 t CO₂ ha⁻¹ yr⁻¹. This value represents a conservative downward adjustment from the midpoint of observed rates, applied to account for the prevalence of smallholder, low-input plantation management in Nigeria. This baseline falls within the IPCC Tier 1 default range for annual carbon accumulation in tropical perennial tree-crop systems (2.0–6.2 t C ha⁻¹ yr⁻¹; IPCC, 2006, Volume 4, Chap. 6), providing independent cross-validation for the coefficient choice. Although no Nigeria-specific field measurements of cashew carbon stocks are currently available in the published literature, the West and Central African study sites from which the coefficients are derived (Togo, Côte d’Ivoire, Cameroon and Benin) share the Guinea and Sudan Savanna agro-ecological zones that dominate Nigeria’s major cashew-producing states (Kogi, Kwara, Oyo, Enugu and Anambra). This agro-ecological alignment supports the transferability of regional coefficients, as soil characteristics, rainfall seasonality, temperature regimes and land management practices are broadly comparable (Nair et al., 2009; Zomer et al., 2016). To account for uncertainty in plantation characteristics and management conditions, sensitivity analysis is conducted using three scenarios: a lower bound of 3.5 t C ha⁻¹ yr⁻¹ (12.8 t CO₂ ha⁻¹ yr⁻¹), representing predominantly mature plantations with minimal management; a baseline value of 4.5 t C ha⁻¹ yr⁻¹ (16.5 t CO₂ ha⁻¹ yr⁻¹), representing mixed age classes with moderate management intensity; and an upper bound of 6.0 t C ha⁻¹ yr⁻¹ (22.0 t CO₂ ha⁻¹ yr⁻¹), representing predominantly young, well-managed plantations with optimal growth conditions. Mitigation Contribution within the Agri-Food System To assess the relative significance of cashew sequestration within the broader agri-food emission context, the study computes the mitigation contribution ratio: MC t = CS t / AFSCO2 t where AFSCO2t denotes observed agri-food system CO₂ emissions reported by FAOSTAT. This ratio indicates the proportion of agri-food system emissions that is attributable to carbon sequestration from cashew cultivation. Data Analysis and Visualization Data were analyzed using R (version 4.5.2) and Microsoft Excel. Derived variables were computed from cleaned FAOSTAT time-series data and descriptive statistics were generated for all key variables. Graphical outputs were produced to illustrate trends and scenario comparisons. RESULTS Descriptive Statistics of Key Study Variables Table 1 presents the descriptive statistics for all key study variables over the 34-year panel (1990–2023). Total agri-food CO₂ emissions averaged 50,349.87 kt over the study period, with a standard deviation of 3,308.13 kt, reflecting gradual growth from a minimum of 47,026.76 kt to a maximum of 56,924.63 kt. Per-capita emissions exhibited a declining trend on average (mean = 0.96 t CO₂/person), consistent with population growth outpacing total emission increases and ranged from 0.78 to 1.17 t CO₂/person across the study period. Cashew harvested area averaged 212,105.56 ha, but with a high standard deviation of 90,108.61 ha that reflects the sharp three-phase trajectory expansion, contraction and stabilization documented in the cultivation trends. Cashew production averaged 294,538.81 tonnes and showed the widest relative variability (SD = 254,267.48 tonnes), with values ranging from 30,000 tonnes at the start of the study period to a peak of 800,000 tonnes. Under the baseline sequestration scenario, average annual carbon sequestration was estimated at 3,499.74 kt CO₂ yr⁻¹ (SD = 1,486.79), ranging from 825.00 kt CO₂ to 6,311.40 kt CO₂. The mitigation contribution ratio averaged 7.03% under the baseline scenario, with a range of 1.75–12.70%, indicating that the relative offset capacity of cashew sequestration varied substantially with changes in cultivated area. Together, these statistics confirm that land-use dynamics as captured by cashew harvested area are the principal source of variability in both sequestration estimates and mitigation contributions across the study period. Table 1 Descriptive Statistics of Key Study Variables, Nigeria (1990–2023) Variable Mean Std. Dev. Minimum Maximum Agri-food Emissions (kt CO2) 50,349.87 3,308.13 47,026.76 56,924.63 Per Capita Emissions (t CO2/person) 0.96 0.13 0.78 1.17 Cashew Harvested Area (ha) 212,105.56 90,108.61 50,000.00 382,509.00 Cashew Production (tonnes) 294,538.81 254,267.48 30,000.00 800,000.00 Seq. Low (kt CO2/yr) 2,714.95 1,153.39 640.00 4,896.12 Seq. Baseline (kt CO2/yr) 3,499.74 1,486.79 825.00 6,311.40 Seq. High (kt CO2/yr) 4,666.32 1,982.39 1,100.00 8,415.20 Contribution Low (%) 5.45 2.44 1.36 9.85 Contribution Baseline (%) 7.03 3.15 1.75 12.70 Contribution High (%) 9.37 4.20 2.33 16.93 Notes: Seq. = carbon sequestration from cashew plantations. Contribution = cashew sequestration as % of total agri-food CO2 emissions. Low = 3.5 t C/ha/yr; Baseline = 4.5 t C/ha/yr; High = 6.0 t C/ha/yr. Source: FAOSTAT (2024). n = 34 observations (1990–2023). Trends in Agri-food CO₂ Emissions in Nigeria (1990–2023) Figure 1 a and Fig. 1 b present the long-term trends in total and per capita agri-food CO₂ emissions in Nigeria from 1990 to 2023. Total agri-food CO₂ emissions increased considerably over the study period, rising from approximately 47,027 kt CO₂ in 1990 to about 56,925 kt CO₂ by 2023, an increase of approximately 21%. This upward trend reflects the growing scale of Nigeria’s food production and distribution activities, driven by population growth, agricultural expansion and intensifying food supply chain activities. The observed pattern is consistent with global trends where agri-food systems have become an increasingly important contributor to greenhouse gas emissions (Crippa et al., 2021). Despite the increase in total emissions, per capita emissions exhibited a declining trend, falling from 1.17 t CO₂ per person in 1990 to 0.78 t CO₂ per person in 2023. Nigeria’s population expanded rapidly during the study period, exceeding 220 million by the early 2020s, thereby diluting emissions on a per-person basis. This divergence rising aggregate emissions alongside declining per-capita intensity is visually captured in Fig. 1 b, which displays both series on a dual-axis time-series chart and is further supported by the descriptive statistics in Table 1 , where the mean per-capita emission of 0.96 t CO₂/person masks a declining trend over the panel period. Evolution of Cashew Cultivation in Nigeria Figure 2 presents the long-term trends in cashew cultivation in Nigeria between 1990 and 2023, focusing on changes in harvested area (CHA) and total production (Cpro). The results reveal three distinct phases in the evolution of the cashew sector over the study period. First, the period 1990–2010 was characterized by a rapid expansion in both harvested area and production. The area under cashew cultivation increased substantially from 50,000 hectares in 1990 to approximately 382,509 hectares in 2010, representing more than a seven-fold increase. Cashew production followed a similar upward trajectory, rising from 30,000 tonnes in 1990 to about 791,726 tonnes in 2010. This phase reflects the rapid commercialization of cashew production and increased farmer participation in the sector, driven by favorable agro-ecological conditions, the adaptability of cashew trees to marginal soils and rising global demand for cashew kernels (Mitchell et al., 2022; Aliyu, 2012). Second, a sharp contraction occurred between 2011 and 2014, during which both harvested area and production declined significantly. The harvested area fell from 337,466 hectares in 2011 to about 126,490 hectares in 2014, while production dropped from 562,572 tonnes to approximately 99,010 tonnes during the same period. This decline represents the most significant structural shift in the dataset and likely reflects a combination of aging cashew tree plantations, limited access to improved planting materials, pest infestations, fluctuating market prices and possible revisions in FAOSTAT statistical estimation methodology (Aliyu, 2012; Akinwale & Esan, 2019). Third, the period 2015–2023 shows a gradual stabilization and partial recovery of the sector. Harvested area increased modestly from 131,529 hectares in 2015 to 171,383 hectares in 2023, although production remained relatively lower compared with the peak levels observed in the late 2000s. Overall, while cashew cultivation expanded significantly during the early decades of the study period, the sector experienced structural adjustments in the 2010s that have not yet been fully reversed. Carbon Sequestration Potential of Cashew Cultivation in Nigeria Figure 3 a presents the estimated carbon sequestration potential associated with cashew cultivation in Nigeria between 1990 and 2023 under three scenarios: low, baseline and high sequestration rates. The estimates were derived by applying sequestration coefficients of 3.5 t C ha⁻¹ yr⁻¹ (12.8 t CO₂ ha⁻¹ yr⁻¹), 4.5 t C ha⁻¹ yr⁻¹ (16.5 t CO₂ ha⁻¹ yr⁻¹) and 6.0 t C ha⁻¹ yr⁻¹ (22.0 t CO₂ ha⁻¹ yr⁻¹) to the annual cashew harvested area. The results show that cashew cultivation represents a substantial carbon sink within Nigeria’s agricultural landscape, although sequestration levels vary significantly across time due to changes in cultivated area. Under the baseline scenario, total carbon sequestration increased from 825 kt CO₂ in 1990 to a peak of approximately 6,311 kt CO₂ in 2010, reflecting the rapid expansion of cashew cultivation during the early decades of the study period. Following the contraction of harvested area after 2010, sequestration levels declined but stabilized in recent years, reaching approximately 2,828 kt CO₂ in 2023. Across the entire study period, the average annual sequestration levels are estimated at 2,668 kt CO₂ under the low scenario, 3,438 kt CO₂ under the baseline scenario and 4,584 kt CO₂ under the high scenario. These values illustrate the potential contribution of cashew plantations to climate change mitigation within Nigeria’s agri-food systems, even under conservative assumptions regarding sequestration rates. The sensitivity analysis highlights the significant influence of sequestration coefficients on total mitigation estimates. Under the low scenario, annual sequestration remains consistently below 5,000 kt CO₂, whereas the high scenario produces estimates exceeding 8,400 kt CO₂ during peak expansion years such as 2010. Despite these differences, the general pattern of sequestration closely follows the trajectory of cashew cultivated area, confirming that land-use expansion is the primary driver of sequestration dynamics in this context. Figure 3 b presents the same sequestration scenarios in a publication-quality ribbon format. The shaded uncertainty band, spanning the full range between the low and high scenario bounds, clearly visualizes how the choice of sequestration coefficient amplifies or dampens estimated carbon uptake over time. The ribbon is narrowest during the early 1990s when cashew area was limited and widens substantially during the 2005–2010 peak expansion period, with a spread of approximately 3,519 kt CO₂ between the low and high scenario estimates in 2010 alone. This widening underscores the sensitivity of national-level sequestration totals to coefficient uncertainty and reinforces the importance of the scenario-based approach. The post-2014 narrowing of the ribbon reflects the contraction and stabilization of cashew cultivated area and confirms that land-use extent remains the dominant driver of sequestration variability. Contribution of Carbon Sequestration to Offset Agri-food Carbon Emissions under Low, Baseline and High Scenarios Figure 4 a shows the estimated percentage contribution of carbon sequestration to offset agri-food carbon emissions under three scenarios: low, baseline and high sequestration potentials. The results indicate that the contribution of carbon sequestration to offset agricultural emissions varied substantially over time, ranging from 1.36–9.85% (low scenario), 1.75–12.70% (baseline scenario) and 2.33–16.93% (high scenario). These variations reflect differences in sequestration capacity, land management practices and potential improvements in carbon capture efficiency. At the beginning of the study period (early 1990s), the contribution of carbon sequestration to offset agricultural emissions was relatively small across all scenarios. Under the baseline scenario, the contribution ranged from approximately 1.75% to about 5.41%, while the low and high scenarios ranged between 1.36–4.20% and 2.33–7.22%, respectively. As the years progressed toward the mid-2000s, the contribution of carbon sequestration increased significantly across all scenarios. The baseline scenario increased steadily to around 10–11%, while the high scenario exceeded 14–15% in some years. The highest contribution occurred when the baseline scenario reached approximately 12.70% and the high scenario peaked at about 16.93%. However, after the peak period, a noticeable decline in the contribution percentages was observed across the three scenarios. The baseline contribution dropped from values above 11–12% to approximately 3.94–5.32%, while the high scenario declined to roughly 5.25–7.09% in some years. In the later years (post-2015), the contribution values stabilize at relatively moderate levels. Under the baseline scenario, the contribution fluctuates between approximately 4.19% and 4.97%, while the low and high scenarios range between 3.25–3.86% and 5.59–6.63%, respectively. Overall, on average, cashew-based sequestration contributed about 2.67%, 3.44% and 4.58% of total agri-food emissions under the low, baseline and high scenarios, respectively, with peak contributions reaching approximately 9.85%, 12.70% and 16.93%. Figure 4 b complements Fig. 4 a by displaying the mitigation contribution ratios for all three scenarios simultaneously with overlapping area fills and clearly differentiated colour-coded lines, enabling direct cross-scenario comparison across the full study period. Three horizontal dashed benchmark lines at 5%, 10% and 15% serve as practical policy reference thresholds. Under the baseline scenario, cashew sequestration crossed the 5% threshold from the early 2000s onward and approached the 10% threshold during the 2005–2010 expansion peak, while the high scenario briefly surpassed the 15% mark in 2010. The post-peak decline in all three scenario lines is conspicuous in Fig. 4 b and the 2011–2014 data anomaly period is visually highlighted by a shaded band, reinforcing caution in interpreting contribution estimates during that sub-period. The stabilization of all three lines in the 3–7% range after 2015 demonstrates that, even at current cultivation levels, cashew plantations continue to provide a non-trivial but moderate carbon offset within Nigeria’s agri-food emission budget. DISCUSSION The observed increase in total emissions from Nigeria’s agri-food systems reflects the growing scale and complexity of the country’s food production and distribution activities. Similar trends have been documented globally, where agri-food systems have become an increasingly important contributor to greenhouse gas emissions. Recent global assessments indicate that food systems account for roughly one-third of total anthropogenic greenhouse gas emissions, with significant contributions arising from agricultural production, land-use change and food supply chain activities such as processing, transport and consumption (Crippa et al., 2021). These dynamics underscore the central role of agriculture in the climate change mitigation agenda, particularly in developing economies where agricultural expansion remains a key driver of economic growth and food security. The gradual increase in emissions observed over the study period likely reflects structural transformations within Nigeria’s agricultural sector. Rapid population growth, urbanization and changing dietary patterns have intensified demand for food, thereby encouraging agricultural expansion and increased use of production inputs. According to the Food and Agriculture Organization, agri-food system emissions have grown significantly in many developing countries due to rising production demands and expanding food supply chains (FAO, 2023). Nigeria, as Africa’s most populous country, has experienced substantial pressure on its agricultural systems to meet domestic food requirements, which partly explains the observed rise in emissions. Despite the increase in total emissions, the consistent decline in per-capita emissions, falling from 1.17 t CO₂ per person in 1990 to 0.78 t CO₂ per person in 2023 suggests that population growth has outpaced the increase in emissions over time. Similar patterns have been observed in several developing economies where expanding food production systems generate higher total emissions while improvements in productivity and technological adoption gradually reduce emission intensity (Mrówczyńska-Kamińska et al., 2021). The declining trend in per-capita emissions may also reflect gradual improvements in the efficiency of agricultural production systems and evolving land-use practices. Nevertheless, the continued rise in total emissions highlights the persistent challenge of balancing agricultural development with environmental sustainability. As emphasized by the Intergovernmental Panel on Climate Change, sustainable land management and climate-smart agriculture are essential strategies for reducing emissions while maintaining food production (IPCC, 2021). The expansion of cashew cultivation observed between 1990 and 2010 reflects the growing importance of the crop within Nigeria’s agricultural diversification strategy. Nigeria is currently among the leading cashew-producing countries in Africa and plays an important role in the global cashew value chain (Mitchell et al., 2022). The rapid expansion in harvested area during the early years of the study is consistent with broader trends in global cashew production, where rising international demand for cashew kernels has encouraged increased cultivation in tropical producing regions. Several factors contributed to the growth of the sector during this period: favorable agro-ecological conditions and the adaptability of cashew trees to marginal soils facilitated expansion across multiple agro-ecological zones (Aliyu, 2012), while increasing global demand for cashew kernels created strong incentives for farmers to expand production to participate in export markets (Mitchell et al., 2022). The sharp contraction observed between 2011 and 2014 may be associated with several structural challenges within the sector. Previous studies have highlighted issues such as aging cashew tree plantations, limited access to improved planting materials, pest infestations and fluctuating market prices as key constraints affecting cashew productivity in Nigeria (Aliyu, 2012; Akinwale & Esan, 2019). The partial recovery observed after 2015 suggests a gradual stabilization of the sector, although production levels remain below the peak values recorded in the late 2000s, suggesting that productivity constraints remain a significant challenge. The results demonstrate that cashew cultivation has the potential to function as an important carbon sink within Nigeria’s agricultural systems. The magnitude of sequestration estimated in this study is consistent with findings from agroforestry research, which shows that tree-based agricultural systems can store significant amounts of carbon in both biomass and soils, with typical sequestration rates of 2–9 t C ha⁻¹ yr⁻¹ depending on species composition, climatic conditions and management practices (Nair et al., 2009; Lal, 2020). The strong relationship between cashew harvested area and total sequestration highlights the importance of land-use dynamics in determining the mitigation potential of agricultural tree crops. Similar patterns have been observed in other tropical tree-crop systems, where increases in plantation area significantly enhance landscape-level carbon storage (Somarriba et al., 2013; Zomer et al., 2016). The relatively low offset capacity observed in the early years of the study (early 1990s) suggests that during this period, carbon sequestration mechanisms were still limited in their capacity to counterbalance emissions from agricultural production systems. Similar observations have been reported in global studies where early agricultural systems showed low mitigation potential due to limited adoption of climate-smart agricultural practices (Smith et al., 2014). As documented in Table 1 , the minimum contribution ratio under the baseline scenario was 1.75%, recorded in 1990, consistent with the limited cashew area (50,000 ha) at the start of the study period. Figure 4 b visually confirms this early period suppression, with all three scenario lines clustering near the lower portion of the chart before the 5% benchmark until the late 1990s. The significant increase in the contribution of carbon sequestration toward the mid-2000s, where the baseline scenario climbed to around 10–12% and the high scenario exceeded 14–16%, suggests that enhanced carbon storage in soils and vegetation increased the system’s ability to offset agricultural emissions. Research has shown that improved soil management, agroforestry expansion and conservation agriculture can significantly enhance carbon sequestration, thereby reducing the net carbon footprint of agricultural production systems (Lal, 2004; Paustian et al., 2016). This peak period is clearly depicted in Fig. 4 b, where all three scenario lines approach or breach the 10% and 15% benchmark reference lines between 2005 and 2010, with the baseline scenario reaching its maximum of 12.70% and the high scenario peaking at 16.93%, the highest values recorded in the entire study period (Table 1 ). The subsequent decline in contribution percentages after the peak period likely reflects increased agricultural emissions relative to the sequestration capacity, due to intensified agricultural activities, expansion of cultivated land and reduced effectiveness of carbon sinks. Agricultural expansion and increased fertilizer use are known to elevate greenhouse gas emissions, often outpacing the capacity of soils and vegetation to sequester carbon (IPCC, 2021). The stabilization of contribution values in the later years may indicate that the system has reached a balance between emission generation and sequestration potential and that the carbon sequestration capacity of the agricultural landscape has approached a saturation point, beyond which additional sequestration becomes more difficult without significant technological or management changes. Soil carbon saturation is a well-documented phenomenon, where soils reach equilibrium after prolonged sequestration efforts (Lal, 2018). The results demonstrate that although carbon sequestration contributes to mitigating agri-food carbon emissions, its contribution remains relatively modest compared to total emissions. Even under the high scenario, the offset potential rarely exceeds 17%, indicating that sequestration alone cannot fully neutralize emissions from agricultural production systems. This finding is consistent with global assessments which emphasize that while carbon sequestration is an important climate mitigation strategy, it must be complemented by emission reduction strategies such as improved fertilizer management, reduced deforestation and adoption of climate-smart agriculture (Smith et al., 2014; IPCC, 2021). The full distribution of contribution values across scenarios and years is summarized in Table 1 , which reports a mean baseline contribution of 7.03% (SD = 3.15%) and Fig. 4 b provides visual confirmation that even the high scenario line remains consistently below the 15% benchmark reference after 2014, underscoring the structural constraint that cashew area decline has imposed on Nigeria’s agricultural carbon offset capacity. Increasing the role of carbon sequestration in offsetting agri-food emissions will therefore require integrated land management approaches, including expansion of agroforestry systems, conservation tillage, restoration of degraded soils and improved pasture management (Paustian et al., 2016; Lal, 2018). Limitations and Future Research Directions This study has several limitations that should be considered when interpreting the results. Carbon sequestration estimates were derived from area-weighted agroforestry coefficients calibrated using data from Togo, Côte d’Ivoire, Cameroon, and Benin rather than Nigeria-specific field measurements. Although agro-ecological similarities support the applicability of these coefficients, the lack of country-specific empirical data introduces some uncertainty beyond what is captured in the sensitivity analysis. In addition, a uniform sequestration coefficient was applied across the entire cashew harvested area, without explicitly accounting for variations in plantation age structure, tree density, soil conditions, or potential land-use changes within production systems. Also, the FAOSTAT cashew dataset exhibits a known structural break between 2011 and 2014, which may affect the consistency of estimates within this period. Finally, the MCt ratio represents a gross carbon offset and does not incorporate emissions associated with cashew production processes, indicating that the net mitigation contribution may be lower than reported. Future research should prioritize field-level carbon stock measurements in Nigeria’s major cashew-producing states to validate and refine the regional sequestration coefficients applied here. Additionally, household and farm-level economic analyses that quantify the cost-effectiveness of cashew-based carbon sequestration relative to alternative land uses would strengthen the policy case for targeted support to the cashew sector within Nigeria’s NDC implementation framework. Integration of remote sensing data to track cashew area dynamics with finer temporal and spatial resolution would also improve the accuracy of national-level sequestration accounting. CONCLUSION This study assessed the relationship between agri-food carbon emissions and cashew-based carbon sequestration and evaluated the extent to which cashew cultivation contributes to offsetting emissions within the agri-food system over the period 1990–2023. The findings reveal that while agri-food emissions increased by approximately 21% over the study period, cashew cultivation provided a meaningful but partial offset, with peak contributions reaching approximately 12.70% of agri-food emissions under the baseline scenario. The study identifies a three-phase trajectory in cashew-related sequestration that mirrors the evolution of cultivated area, confirming land-use extent as the primary driver of national-level cashew carbon storage. These findings highlight that cashew cultivation can function as a genuine but complementary climate mitigation strategy and that expanding cashew cultivation, particularly on degraded lands remains a viable option for enhancing Nigeria’s agricultural carbon balance. These findings have direct relevance for Nigeria’s Nationally Determined Contribution commitments under the Paris Agreement and suggest that a well-monitored expansion of cashew cultivation on degraded lands could qualify for inclusion in Voluntary Carbon Market (VCM) schemes, generating co-benefits for smallholder farmers and national climate targets simultaneously. Recommendations Based on the findings of this study, the following recommendations are proposed to enhance carbon mitigation within the agri-food system: 1. Strengthening Carbon Sequestration Practices in Agricultural Systems Given that the study found carbon sequestration contributes only a modest proportion toward offsetting agri-food carbon emissions, there is a need to strengthen land management practices that enhance carbon storage. Practices such as improved soil management, conservation agriculture and integration of perennial vegetation should be promoted to increase the carbon sequestration capacity of agricultural landscapes. 2. Adoption of Integrated Emission Reduction and Sequestration Strategies Since carbon sequestration alone was found to be insufficient to fully offset agri-food carbon emissions, mitigation efforts in the agricultural sector should combine both emission reduction and carbon sequestration strategies. This may include improving fertilizer management, adopting low-emission farming techniques and enhancing soil carbon storage to reduce the overall carbon footprint of agricultural production systems. 3. Expansion of Cashew Cultivation to Improve Carbon Sequestration The expansion of cashew cultivation should be encouraged as a strategy to enhance carbon sequestration within agricultural landscapes. Cashew trees, as perennial woody crops, have the ability to store carbon in both above-ground biomass and soil organic matter. Increasing the area under cashew cultivation can therefore improve the carbon sequestration potential of the agri-food system while also supporting farmer livelihoods. However, expansion should prioritize degraded or underutilized agricultural lands to ensure that increased carbon storage is achieved without causing deforestation or additional environmental degradation. Declarations Ethics approval and consent to participate: Not applicable Consent for publication: Not applicable Availability of data and materials: Not applicable Competing interests: The authors declare that they have no competing interests Funding: Not applicable Authors' contributions: Q.A.O. conceived and designed the study, coordinated the overall research framework, and contributed to the development of the manuscript. O.P.B conducted the literature synthesis, designed the methodology and analysis. O.A contributed to the interpretation and discussion of results. K.A.A supported data compilation, contributed to the literature review and proof-reading of the manuscript. All authors participated in the revision of the manuscript, reviewed the final version critically for intellectual content, and approved the final manuscript for publication. Acknowledgements: Not applicable References Adjei V, Alormu MA. 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Greenhouse gas emissions from agrifood systems: Global, regional and country trends 2000–2021. Rome: FAO; 2023. Intergovernmental Panel on Climate Change. Sixth Assessment Report (AR6). Geneva: IPCC; 2021. Intergovernmental Panel on Climate Change. Climate change 2022: Mitigation of climate change. Cambridge: Cambridge University Press; 2022. Kabato W, Getnet GT, Sinore T, Nemeth A, Molnár Z. Towards climate-smart agriculture: Strategies for sustainable agricultural production, food security and greenhouse gas reduction. Agronomy. 2025;15(3):565. Koffi JK, et al. Carbon dynamics in cashew plantations of Côte d’Ivoire. Int J Environ Clim Change. 2025. Kwiatkowski CA, Pawłowska M, Harasim E, Pawłowski L. Strategies of climate change mitigation in agriculture plant production: A critical review. Energies. 2023;16(10):4225. Lal R. Soil carbon sequestration to mitigate climate change. Geoderma. 2004;123(1–2):1–22. doi:10.1016/j.geoderma.2004.01.032 Lal R. Digging deeper: A holistic perspective of factors affecting soil organic carbon sequestration in agroecosystems. Glob Change Biol. 2018;24(8):3285–3301. doi:10.1111/gcb.14054 Lal R. Managing soils for resolving the conflict between agriculture and nature. Eur J Soil Sci. 2020;71(1):1–9. doi:10.1111/ejss.12848 Mitchell T, Keane J, Coles C. Trading up: Global value chains and the cashew sector in West Africa. J Agribus Dev Emerg Econ. 2022;12(4):567–582. Mrówczyńska-Kamińska A, Bajan B, Pawłowski KP, Genstwa N, Zmyślona J. Greenhouse gas emissions intensity of food production systems and its determinants. PLoS One. 2021;16(4):e0250995. Nair PKR, Kumar BM, Nair VD. Agroforestry as a strategy for carbon sequestration. J Plant Nutr Soil Sci. 2009;172(1):10–23. doi:10.1002/jpln.200800030 Okorie DI, Lin B. Emissions in agricultural-based developing economies: A case of Nigeria. J Clean Prod. 2022;337:130570. Paustian K, Lehmann J, Ogle S, Reay D, Robertson G, Smith P. Climate-smart soils. Nature. 2016;532:49–57. doi:10.1038/nature17174 Smith P, Bustamante M, Ahammad H, Clark H, Dong H, Elsiddig E, et al. Agriculture, forestry and other land use (AFOLU). In: Climate change 2014: Mitigation of climate change. Cambridge: Cambridge University Press; 2014. Somarriba E, Cerda R, Orozco L, Cifuentes M, Davila H, Espin T, et al. Carbon stocks and cocoa yields in agroforestry systems of Central America. Agric Ecosyst Environ. 2013;173:46–57. doi:10.1016/j.agee.2013.04.013 Steensland A, Zeigler M. Productivity in agriculture for a sustainable future. In: The innovation revolution in agriculture: A roadmap to value creation. Cham: Springer; 2020. p. 33–69. Suleiman IA, Anakhu EA. Modelling and evaluation of the effects of deforestation on carbon stocks in Nigeria: A case study of 36 states and the FCT. J Res Environ Earth Sci. 2023;9(4):180–188. Victor A, Noumi V, Zapfack L. Soil organic carbon in cashew agroecosystems of Cameroon. Am J Agric Biol Sci. 2020. Zomer RJ, Neufeldt H, Xu J, Ahrends A, Bossio D, Trabucco A, et al. Global tree cover and biomass carbon on agricultural land: The contribution of agroforestry to global and national carbon budgets. Sci Rep. 2016;6(1):29987. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviews received at journal 07 May, 2026 Reviewers agreed at journal 25 Apr, 2026 Reviewers invited by journal 23 Apr, 2026 Editor invited by journal 23 Apr, 2026 Editor assigned by journal 22 Apr, 2026 Submission checks completed at journal 22 Apr, 2026 First submitted to journal 18 Apr, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9456126","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":633627142,"identity":"e3c74d34-e846-4e29-8af0-80b91c07c84c","order_by":0,"name":"Qudus Adebayo OGUNWOLU","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA20lEQVRIiWNgGAWjYHACAyjNfABISMiQooUtAaSFhxQtPGAGYS18N5K3Sf6oqE3czn/m86sbNRY8DOyHj27Ap0XyRlqZNM+Z44k7G85us845BnQYT1raDbyuupFjJs3Ydixxw8HebcY5bEAtEjxmBLVI/gRpOczzzDjnH5FaJHjbahI3HONhfpzbRoQWyTPPiq15zhww3nCGzYw5t0+Ch42QX/iOJ2+8+aOiTnbD+cOPP+d8q5PjZz98DK8WhgNg8jCIYJMAk3iVI7TUgQjmDwRVj4JRMApGwYgEAJB8S7c5svLdAAAAAElFTkSuQmCC","orcid":"","institution":"Cocoa Research Institute of Nigeria","correspondingAuthor":true,"prefix":"","firstName":"Qudus","middleName":"Adebayo","lastName":"OGUNWOLU","suffix":""},{"id":633627155,"identity":"c59b934d-e3cb-4e1d-a8c4-ad7d1994551b","order_by":1,"name":"Olaitan Paul BABATUNDE","email":"","orcid":"","institution":"Cocoa Research Institute of Nigeria","correspondingAuthor":false,"prefix":"","firstName":"Olaitan","middleName":"Paul","lastName":"BABATUNDE","suffix":""},{"id":633627157,"identity":"6c84baa3-e60b-4ff4-902b-1e0f4e8048a6","order_by":2,"name":"Olufemi AREMU-DELE","email":"","orcid":"","institution":"Cocoa Research Institute of Nigeria","correspondingAuthor":false,"prefix":"","firstName":"Olufemi","middleName":"","lastName":"AREMU-DELE","suffix":""},{"id":633627159,"identity":"f5fbbd66-76d0-4ab5-b097-7d65b55aeb52","order_by":3,"name":"Kehinde Ademola ADESANYA","email":"","orcid":"","institution":"Cocoa Research Institute of Nigeria","correspondingAuthor":false,"prefix":"","firstName":"Kehinde","middleName":"Ademola","lastName":"ADESANYA","suffix":""}],"badges":[],"createdAt":"2026-04-18 11:38:35","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9456126/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9456126/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":108493808,"identity":"e597920f-d59f-4d51-a300-73bc39959551","added_by":"auto","created_at":"2026-05-05 10:01:49","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":125022,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eFigure 1a: Trend of Agri-food total and per capita emission\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-9456126/v1/40780b3a06297e7210751f19.jpg"},{"id":108424072,"identity":"951a0fde-4611-4508-9e2e-1ef081fc0bc0","added_by":"auto","created_at":"2026-05-04 13:22:09","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":48816,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eFigure 1b. Trends in Agri-food CO₂ Emissions in Nigeria (1990-2023)\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-9456126/v1/66620cba26ec08963535caad.jpg"},{"id":108424073,"identity":"700fd4c4-1b1c-4226-88c0-faf3491f4e69","added_by":"auto","created_at":"2026-05-04 13:22:09","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":82049,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eFigure 2: Trend of cashew production and harvested area\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-9456126/v1/b38768017f7c5602bff6a6d2.jpg"},{"id":108424074,"identity":"cfa12d88-137c-406d-abcb-726cb34d1bcb","added_by":"auto","created_at":"2026-05-04 13:22:09","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":95074,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eFigure 3a: Carbon Sequestered by Cashew Trees under different scenarios\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-9456126/v1/f0614bbadcfae2f5f6ad7f2a.jpg"},{"id":108803727,"identity":"a60499e4-cd51-433b-a023-54c05e7785b7","added_by":"auto","created_at":"2026-05-08 15:05:00","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":46280,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eFigure 3b. Carbon sequestration potential of cashew cultivation in Nigeria (1990-2023)\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-9456126/v1/9e588f7bb3f9d03246b77f77.jpg"},{"id":108424076,"identity":"7b73995f-5ca7-4e37-8551-d3d4de05a947","added_by":"auto","created_at":"2026-05-04 13:22:09","extension":"jpg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":126345,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eFigure 4a: Cashew carbon sequestration to offset agri-food emission under different scenarios\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"6.jpg","url":"https://assets-eu.researchsquare.com/files/rs-9456126/v1/a2fb806a2c5cef334304a25c.jpg"},{"id":108424078,"identity":"12c3abff-f5aa-4697-8f62-0f9f3a071794","added_by":"auto","created_at":"2026-05-04 13:22:09","extension":"jpg","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":70201,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eFigure 4b. Contribution of cashew sequestration to offsetting Agri-Food Emissions (1990-2023)\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"7.jpg","url":"https://assets-eu.researchsquare.com/files/rs-9456126/v1/8aaa943e2d92e9ba4c8cdd57.jpg"},{"id":108808964,"identity":"b2ce2660-6a80-437e-880b-8a72f4af27ef","added_by":"auto","created_at":"2026-05-08 15:48:22","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":872163,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9456126/v1/31fd9c07-38e1-4f2c-9573-23fd4c263013.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eRole of Cashew Cultivation in Mitigating Carbon Emissions in Nigeria's Agri-Food Systems\u003c/p\u003e","fulltext":[{"header":"BACKGROUND","content":"\u003cp\u003eClimate change poses a major global challenge, with the agri-food sector acting as both a significant source of greenhouse gas (GHG) emissions and a potential pathway for mitigation. Globally, agri-food systems contribute about one-third of anthropogenic emissions, driven by agricultural production, land-use change, and supply chain activities (Crippa et al., 2021; Tubiello et al., 2021). In Nigeria, increasing food demand, population growth, and agricultural expansion have intensified emissions from the sector, raising concerns about sustainability.\u003c/p\u003e\n\u003cp\u003eAt the same time, agricultural systems particularly tree-based systems offer opportunities for carbon sequestration. Agroforestry and perennial crops can store substantial carbon in biomass and soils while maintaining productivity (Lal, 2020; Nair et al., 2009). In this context, cashew (Anacardium occidentale), a major export-oriented tree crop in Nigeria, is of growing interest. Beyond its economic importance, cashew cultivation has the potential to function as a carbon sink, with studies in Sub-Saharan Africa reporting significant carbon storage across different plantation ages and management conditions (Bello et al., 2017; Koffi et al., 2025).\u003c/p\u003e\n\u003cp\u003eHowever, existing research has largely focused on plot-level carbon stocks, with limited evidence linking crop-specific sequestration to national agri-food emission dynamics. This gap is particularly evident in Nigeria, where the mitigation role of tree crops within the agri-food system remains underexplored.\u003c/p\u003e\n\u003cp\u003eThis study addresses this gap by examining the role of cashew cultivation in mitigating carbon emissions in Nigeria\u0026rsquo;s agri-food systems. Specifically, it analyzes emission trends, evaluates the evolution of cashew cultivation, estimates its carbon sequestration potential using established coefficients, and assesses its contribution to offsetting emissions under alternative scenarios. The study provides policy-relevant insights into the role of perennial tree crops in advancing climate-smart and sustainable agricultural systems.\u003c/p\u003e"},{"header":"INTRODUCTION","content":"\u003cp\u003eAgriculture plays a central role in Nigeria\u0026rsquo;s economy and food system, providing livelihoods for a large share of the rural population while contributing substantially to national output and export earnings. At the same time, the sector represents a major source of greenhouse gas (GHG) emissions, largely through land-use change, deforestation, soil degradation, fertilizer application and energy use along agri-food value chains (FAO, 2023). Greenhouse gases, including carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O), trap heat in the atmosphere, driving global warming and climate change. In agri-food systems, these emissions arise primarily from enteric fermentation in livestock, rice cultivation, synthetic fertilizer use, manure management, biomass burning and land conversion activities that release stored carbon from vegetation and soils (Crippa et al., 2021). Mitigation in agriculture involves practices that reduce net emissions or enhance carbon removal, such as improved nutrient management, agroforestry and the adoption of perennial crops that build long-term carbon stocks in biomass and soils (Kwiatkowski et al., 2023). In Sub-Saharan Africa, agri-food systems are increasingly recognized as both a driver of climate change and a potential entry point for mitigation strategies that align environmental sustainability with rural development goals (Crippa et al., 2021).\u003c/p\u003e \u003cp\u003eAfrica\u0026rsquo;s agri-food system contributes a significant share of national emissions, reflecting long-standing challenges related to forest conversion, expansion of cropland into carbon-rich ecosystems and low adoption of climate-smart agricultural practices (Steensland and Zeigler, 2020). While policy attention has largely focused on reducing emissions from fossil fuels and energy use, mitigation opportunities within agriculture particularly those linked to carbon sequestration remain underexplored in empirical economic research. This gap is evident given the country\u0026rsquo;s commitments under the Paris Agreement and its Nationally Determined Contribution (NDC), which explicitly recognizes agriculture and land use as priority sectors for climate mitigation and adaptation.\u003c/p\u003e \u003cp\u003ePerennial tree crops have attracted increasing attention in the climate change literature due to their capacity to sequester carbon in above-ground biomass, below-ground biomass and soils, while simultaneously supporting farm incomes and diversification (Nair et al., 2009; Lal, 2020). Agroforestry and tree-based production systems are widely regarded as effective climate-smart agricultural strategies because they generate long-term carbon sinks and reduce pressure on natural forests by stabilizing land use (Kwiatkowski et al., 2023; Zomer et al., 2016). Advances in crop improvement, including the selection and breeding of high-yielding, drought-tolerant cashew varieties with enhanced root systems and biomass allocation, further amplify this sequestration potential while improving resilience to climate variability (Agboka et al., 2025). However, empirical assessments of the mitigation potential of specific export-oriented tree crops at the national scale remain limited, particularly in African contexts. Agriculture accounts for a large portion of Nigeria\u0026rsquo;s greenhouse gas emissions, largely due to deforestation, land degradation and methane from livestock and rice farming (Okorie and Lin, 2023).\u003c/p\u003e \u003cp\u003eCashew (\u003cem\u003eAnacardium occidentale\u003c/em\u003e) has emerged as one of Nigeria\u0026rsquo;s most important non-oil export crops, with rapidly expanding cultivation across major producing states such as Kogi, Kwara, Oyo, Enugu and Anambra. The crop is well-suited to marginal soils, requires relatively low external inputs compared to annual crops and is typically cultivated as a long-lived perennial system (FAO, 2022). Beyond its economic significance, cashew cultivation has the potential to contribute meaningfully to climate change mitigation by increasing tree cover, enhancing soil organic carbon and substituting for more emission-intensive land-use practices (Nair et al., 2009; Victor et al., 2020). Plant breeding efforts that prioritize varieties with greater biomass production and deeper root architectures can further elevate carbon storage in both above and below-ground compartments (Koffi et al., 2025; Agboka et al., 2025). Despite these attributes, the environmental role of cashew production, particularly its contribution to reducing net carbon emissions from agri-food systems, has received little systematic empirical attention. Notably, no prior study has linked Nigeria-specific cashew harvested area data to national agri-food emission trends, representing a gap this study addresses.\u003c/p\u003e \u003cp\u003eExisting studies on agricultural emissions in Nigeria have largely concentrated on livestock systems, fertilizer use, deforestation and aggregate crop production, with limited differentiation across crop types or production systems (Bawa et al., 2023; Suleiman and Anakhu, 2023). Similarly, while the agroforestry literature provides robust evidence on carbon sequestration at plot or farm levels, there is a scarcity of macro-level analyses that link the expansion of specific perennial crops to national agri-food emission trends using consistent time-series data. This gap constrains the ability of policymakers to design crop-specific climate strategies that leverage existing agricultural strengths.\u003c/p\u003e \u003cp\u003eAgainst this backdrop, this study examines the role of cashew cultivation in mitigating carbon emissions within Nigeria\u0026rsquo;s agri-food systems. Using secondary time-series data from internationally recognized sources, the study analyzes trends in agri-food system emissions alongside the expansion of cashew harvested area and production. It further estimates the carbon sequestration potential of cashew cultivation using established coefficients from the agroforestry and climate change literature, enabling an assessment of the extent to which cashew expansion offsets emissions from the broader agri-food system.\u003c/p\u003e\n\u003ch3\u003eTheoretical Framework\u003c/h3\u003e\n\u003cp\u003eThis study is grounded in three complementary theoretical perspectives: (i) agroforestry and carbon sequestration theory, (ii) land-use change and emissions offset theory and (iii) the climate-smart agriculture (CSA) framework. Together, these perspectives provide a coherent explanation of how the expansion of perennial tree crops such as cashew can influence carbon emissions within agri-food systems.\u003c/p\u003e \u003cp\u003eAgroforestry and carbon sequestration theory posits that tree-based agricultural systems act as long-term carbon sinks by storing carbon in above-ground biomass, below-ground biomass and soils (Nair et al., 2009; Lal, 2020). Unlike annual cropping systems, perennial tree crops accumulate carbon over extended periods, resulting in higher carbon residence time and reduced atmospheric CO₂ concentrations. From this perspective, cashew cultivation contributes to climate change mitigation by increasing vegetative carbon stocks and enhancing soil organic carbon, particularly when established on degraded or low-carbon lands (Adjei and Alormu, 2020).\u003c/p\u003e \u003cp\u003eLand-use change and emissions offset theory further explains the mitigation role of perennial crops through their capacity to alter land-use trajectories. Expansion of tree crops can reduce emissions by stabilizing land use, limiting repeated soil disturbance and lowering the likelihood of deforestation driven by shifting cultivation or extensive annual cropping (Zomer et al., 2016). In this framework, cashew cultivation functions as a land-use substitute that partially offsets emissions from more carbon-intensive agricultural activities, thereby influencing net emissions at the agri-food system level.\u003c/p\u003e \u003cp\u003eThe climate-smart agriculture (CSA) framework integrates productivity, adaptation and mitigation objectives, emphasizing practices that simultaneously enhance food security and environmental sustainability (Kabato et al., 2020). Tree-based systems are central to CSA because they combine income generation with ecosystem services, including carbon sequestration and microclimate regulation. Within this framework, cashew cultivation represents a climate-smart pathway through which Nigeria\u0026rsquo;s agri-food system can contribute to emission mitigation without compromising economic performance. Combining these perspectives, the study hypothesizes that expansion in cashew harvested area is associated with a reduction in net agri-food system carbon emissions through increased carbon sequestration and land-use stabilization effects.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eObjectives of the Study\u003c/h2\u003e \u003cp\u003eThe main objective of this study is to examine the role of cashew cultivation in mitigating carbon emissions within Nigeria\u0026rsquo;s agri-food systems. Specifically, the study seeks to:\u003c/p\u003e \u003cp\u003e \u003col\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eAnalyze long-term trends in total and per capita CO₂ emissions from Nigeria\u0026rsquo;s agri-food systems.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eExamine the evolution of cashew cultivation in Nigeria, focusing on changes in harvested area and production over time.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eEstimate the carbon sequestration potential of cashew cultivation in Nigeria using established sequestration coefficients from the agroforestry and climate change literature.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eEvaluate the relative contribution of cashew sequestration to Nigeria\u0026rsquo;s agri-food system carbon balance, including sensitivity analysis across scenarios.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003c/ol\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"METHODS","content":"\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eResearch Design\u003c/h2\u003e \u003cp\u003eThis study adopts a quantitative, time-series research design to examine the role of cashew cultivation in mitigating carbon emissions within Nigeria\u0026rsquo;s agri-food systems. Consistent with the study objectives, the analysis integrates trend analysis, carbon sequestration accounting and sensitivity scenario analysis using secondary data from various sources. This approach is widely employed in macro-level environmental and agricultural economics studies examining the interaction between land use, agricultural production and carbon emissions (Crippa et al., 2021).\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eData Sources and Variables\u003c/h3\u003e\n\u003cp\u003eAnnual data covering the period 1990\u0026ndash;2023 are obtained from the following sources: Agri-food system CO₂ emissions (total and per capita), cashew cultivation harvested area (hectares) and production (metric tonnes) from FAOSTAT. FAOSTAT emissions data follow IPCC guidelines and capture emissions from crop production, land use, fertilizer application and related agri-food activities, making them suitable for national-level environmental analysis (FAO, 2022; IPCC, 2019).\u003c/p\u003e \u003cp\u003eIt is important to note that the FAOSTAT cashew dataset exhibits a sharp discontinuity between 2011 and 2014, during which recorded harvested area fell from approximately 382,000 ha to 126,000 ha. This contraction most likely reflects a revision in FAOSTAT estimation methodology or a change in Nigeria\u0026rsquo;s national agricultural census reporting rather than an actual collapse in cultivation, though no imputation or smoothing was applied to the raw series in this study; the data are used as reported and this sub-period is identified as carrying elevated uncertainty in all derived sequestration estimates. Furthermore, FAOSTAT aggregates all cashew land as a single national category without age-class distribution; for the purposes of this analysis, the entire cashew harvested area is therefore treated as actively sequestering at the applied coefficient rate, which constitutes a known simplifying assumption. Summary statistics for all key variables are presented in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e\n\u003ch3\u003eCarbon Sequestration Estimation\u003c/h3\u003e\n\u003cp\u003eTo address Objectives 3 and 4, the study estimates the carbon sequestration potential of cashew cultivation using a land-area-based accounting approach, consistent with IPCC guidelines and agroforestry literature.\u003c/p\u003e \u003cp\u003e \u003cstrong\u003eSequestration Formula\u003c/strong\u003e \u003cp\u003eCS\u003csub\u003et\u003c/sub\u003e = CHA\u003csub\u003et\u003c/sub\u003e\u0026thinsp;\u0026times;\u0026thinsp;β\u003c/p\u003e \u003c/p\u003e \u003cp\u003ewhere: CSt is the annual amount of CO₂ sequestered (tCO₂/year); CHAt is cashew harvested area (ha); and β is the carbon sequestration coefficient (tCO₂/ha/year). This formulation assumes that the entire harvested cashew area is actively sequestering carbon at a uniform rate and does not account for variation in plantation age structure within Nigeria.\u003c/p\u003e \u003cp\u003eEmpirical evidence from Sub-Saharan Africa indicates that cashew (\u003cem\u003eAnacardium occidentale\u003c/em\u003e) plantations accumulate substantial amounts of carbon in both biomass and soils, providing a sound basis for deriving annualized sequestration rates. Field-based studies in West and Central Africa consistently report total ecosystem carbon stocks in cashew systems ranging between approximately 60 and 100 t C ha⁻\u0026sup1;, depending on plantation age, site conditions and management practices (Victor et al., 2021; Agboka et al., 2025; Koffi et al., 2025). For example, Agboka et al. (2025) measured combined biomass and soil carbon stocks exceeding 80 t C ha⁻\u0026sup1; in ten-year-old cashew plantations in Togo. Chronosequence analyses in C\u0026ocirc;te d\u0026rsquo;Ivoire show that total carbon stocks increase with plantation age, from 71.60\u0026thinsp;\u0026plusmn;\u0026thinsp;6.72 t C ha⁻\u0026sup1; in young plantations to 82.84\u0026thinsp;\u0026plusmn;\u0026thinsp;1.21 t C ha⁻\u0026sup1; in old plantations, equivalent to total CO₂ sequestration ranging from approximately 263 to 305 t CO₂ ha⁻\u0026sup1; (Koffi et al., 2025). Comparable magnitudes have been reported for cashew plantations in Cameroon, where total carbon stocks (biomass plus soil) typically fall within the 60\u0026ndash;97 t C ha⁻\u0026sup1; range (Victor et al., 2020). Additional studies in Benin report total stocks of 63\u0026ndash;85 t C ha⁻\u0026sup1; across climatic gradients, with higher values in transitional zones (Bello et al., 2017).\u003c/p\u003e \u003cp\u003eApplying a conservative annualization approach to the African cashew evidence, annualized rates are derived as follows: for 10-year plantations with ~\u0026thinsp;80 t C ha⁻\u0026sup1;, the rate is 8.0 t C ha⁻\u0026sup1; yr⁻\u0026sup1; (early establishment phase); for 15-year plantations with ~\u0026thinsp;75 t C ha⁻\u0026sup1;, the rate is 5.0 t C ha⁻\u0026sup1; yr⁻\u0026sup1; (active growth phase); and for 20\u0026ndash;25-year plantations with ~\u0026thinsp;85 t C ha⁻\u0026sup1;, the rate is 3.8 t C ha⁻\u0026sup1; yr⁻\u0026sup1; (mature stabilization phase). Given that Nigeria\u0026rsquo;s cashew plantations span multiple age classes and management intensities, this study adopts a moderate baseline sequestration rate of 4.5 t C ha⁻\u0026sup1; yr⁻\u0026sup1;, equivalent to approximately 16.5 t CO₂ ha⁻\u0026sup1; yr⁻\u0026sup1;. This value represents a conservative downward adjustment from the midpoint of observed rates, applied to account for the prevalence of smallholder, low-input plantation management in Nigeria. This baseline falls within the IPCC Tier 1 default range for annual carbon accumulation in tropical perennial tree-crop systems (2.0\u0026ndash;6.2 t C ha⁻\u0026sup1; yr⁻\u0026sup1;; IPCC, 2006, Volume 4, Chap.\u0026nbsp;6), providing independent cross-validation for the coefficient choice.\u003c/p\u003e \u003cp\u003eAlthough no Nigeria-specific field measurements of cashew carbon stocks are currently available in the published literature, the West and Central African study sites from which the coefficients are derived (Togo, C\u0026ocirc;te d\u0026rsquo;Ivoire, Cameroon and Benin) share the Guinea and Sudan Savanna agro-ecological zones that dominate Nigeria\u0026rsquo;s major cashew-producing states (Kogi, Kwara, Oyo, Enugu and Anambra). This agro-ecological alignment supports the transferability of regional coefficients, as soil characteristics, rainfall seasonality, temperature regimes and land management practices are broadly comparable (Nair et al., 2009; Zomer et al., 2016).\u003c/p\u003e \u003cp\u003eTo account for uncertainty in plantation characteristics and management conditions, sensitivity analysis is conducted using three scenarios: a lower bound of 3.5 t C ha⁻\u0026sup1; yr⁻\u0026sup1; (12.8 t CO₂ ha⁻\u0026sup1; yr⁻\u0026sup1;), representing predominantly mature plantations with minimal management; a baseline value of 4.5 t C ha⁻\u0026sup1; yr⁻\u0026sup1; (16.5 t CO₂ ha⁻\u0026sup1; yr⁻\u0026sup1;), representing mixed age classes with moderate management intensity; and an upper bound of 6.0 t C ha⁻\u0026sup1; yr⁻\u0026sup1; (22.0 t CO₂ ha⁻\u0026sup1; yr⁻\u0026sup1;), representing predominantly young, well-managed plantations with optimal growth conditions.\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eMitigation Contribution within the Agri-Food System\u003c/h2\u003e \u003cp\u003eTo assess the relative significance of cashew sequestration within the broader agri-food emission context, the study computes the mitigation contribution ratio:\u003c/p\u003e \u003cp\u003eMC\u003csub\u003et\u003c/sub\u003e = CS\u003csub\u003et\u003c/sub\u003e / AFSCO2\u003csub\u003et\u003c/sub\u003e\u003c/p\u003e \u003cp\u003ewhere AFSCO2t denotes observed agri-food system CO₂ emissions reported by FAOSTAT. This ratio indicates the proportion of agri-food system emissions that is attributable to carbon sequestration from cashew cultivation.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eData Analysis and Visualization\u003c/h3\u003e\n\u003cp\u003eData were analyzed using R (version 4.5.2) and Microsoft Excel. Derived variables were computed from cleaned FAOSTAT time-series data and descriptive statistics were generated for all key variables. Graphical outputs were produced to illustrate trends and scenario comparisons.\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eDescriptive Statistics of Key Study Variables\u003c/h2\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e presents the descriptive statistics for all key study variables over the 34-year panel (1990\u0026ndash;2023). Total agri-food CO₂ emissions averaged 50,349.87 kt over the study period, with a standard deviation of 3,308.13 kt, reflecting gradual growth from a minimum of 47,026.76 kt to a maximum of 56,924.63 kt. Per-capita emissions exhibited a declining trend on average (mean\u0026thinsp;=\u0026thinsp;0.96 t CO₂/person), consistent with population growth outpacing total emission increases and ranged from 0.78 to 1.17 t CO₂/person across the study period. Cashew harvested area averaged 212,105.56 ha, but with a high standard deviation of 90,108.61 ha that reflects the sharp three-phase trajectory expansion, contraction and stabilization documented in the cultivation trends. Cashew production averaged 294,538.81 tonnes and showed the widest relative variability (SD\u0026thinsp;=\u0026thinsp;254,267.48 tonnes), with values ranging from 30,000 tonnes at the start of the study period to a peak of 800,000 tonnes. Under the baseline sequestration scenario, average annual carbon sequestration was estimated at 3,499.74 kt CO₂ yr⁻\u0026sup1; (SD\u0026thinsp;=\u0026thinsp;1,486.79), ranging from 825.00 kt CO₂ to 6,311.40 kt CO₂. The mitigation contribution ratio averaged 7.03% under the baseline scenario, with a range of 1.75\u0026ndash;12.70%, indicating that the relative offset capacity of cashew sequestration varied substantially with changes in cultivated area. Together, these statistics confirm that land-use dynamics as captured by cashew harvested area are the principal source of variability in both sequestration estimates and mitigation contributions across the study period.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDescriptive Statistics of Key Study Variables, Nigeria (1990\u0026ndash;2023)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMean\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eStd. Dev.\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMinimum\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMaximum\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAgri-food Emissions (kt CO2)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e50,349.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e3,308.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e47,026.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e56,924.63\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePer Capita Emissions (t CO2/person)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1.17\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eCashew Harvested Area (ha)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e212,105.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e90,108.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e50,000.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e382,509.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eCashew Production (tonnes)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e294,538.81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e254,267.48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e30,000.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e800,000.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSeq.\u0026nbsp;Low (kt CO2/yr)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2,714.95\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1,153.39\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e640.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e4,896.12\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSeq.\u0026nbsp;Baseline (kt CO2/yr)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3,499.74\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1,486.79\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e825.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e6,311.40\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSeq.\u0026nbsp;High (kt CO2/yr)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e4,666.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1,982.39\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1,100.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e8,415.20\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eContribution Low (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e5.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e2.44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e9.85\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eContribution Baseline (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e3.15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e12.70\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eContribution High (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e9.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4.20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e16.93\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003cem\u003eNotes: Seq.\u0026nbsp;= carbon sequestration from cashew plantations. Contribution\u0026thinsp;=\u0026thinsp;cashew sequestration as % of total agri-food CO2 emissions. Low\u0026thinsp;=\u0026thinsp;3.5 t C/ha/yr; Baseline\u0026thinsp;=\u0026thinsp;4.5 t C/ha/yr; High\u0026thinsp;=\u0026thinsp;6.0 t C/ha/yr. Source: FAOSTAT (2024). n\u0026thinsp;=\u0026thinsp;34 observations (1990\u0026ndash;2023).\u003c/em\u003e\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eTrends in Agri-food CO₂ Emissions in Nigeria (1990\u0026ndash;2023)\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e1\u003c/span\u003ea and Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e1\u003c/span\u003eb present the long-term trends in total and per capita agri-food CO₂ emissions in Nigeria from 1990 to 2023. Total agri-food CO₂ emissions increased considerably over the study period, rising from approximately 47,027 kt CO₂ in 1990 to about 56,925 kt CO₂ by 2023, an increase of approximately 21%. This upward trend reflects the growing scale of Nigeria\u0026rsquo;s food production and distribution activities, driven by population growth, agricultural expansion and intensifying food supply chain activities. The observed pattern is consistent with global trends where agri-food systems have become an increasingly important contributor to greenhouse gas emissions (Crippa et al., 2021).\u003c/p\u003e \u003cp\u003eDespite the increase in total emissions, per capita emissions exhibited a declining trend, falling from 1.17 t CO₂ per person in 1990 to 0.78 t CO₂ per person in 2023. Nigeria\u0026rsquo;s population expanded rapidly during the study period, exceeding 220\u0026nbsp;million by the early 2020s, thereby diluting emissions on a per-person basis. This divergence rising aggregate emissions alongside declining per-capita intensity is visually captured in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e1\u003c/span\u003eb, which displays both series on a dual-axis time-series chart and is further supported by the descriptive statistics in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, where the mean per-capita emission of 0.96 t CO₂/person masks a declining trend over the panel period.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eEvolution of Cashew Cultivation in Nigeria\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e2\u003c/span\u003e presents the long-term trends in cashew cultivation in Nigeria between 1990 and 2023, focusing on changes in harvested area (CHA) and total production (Cpro). The results reveal three distinct phases in the evolution of the cashew sector over the study period.\u003c/p\u003e \u003cp\u003eFirst, the period 1990\u0026ndash;2010 was characterized by a rapid expansion in both harvested area and production. The area under cashew cultivation increased substantially from 50,000 hectares in 1990 to approximately 382,509 hectares in 2010, representing more than a seven-fold increase. Cashew production followed a similar upward trajectory, rising from 30,000 tonnes in 1990 to about 791,726 tonnes in 2010. This phase reflects the rapid commercialization of cashew production and increased farmer participation in the sector, driven by favorable agro-ecological conditions, the adaptability of cashew trees to marginal soils and rising global demand for cashew kernels (Mitchell et al., 2022; Aliyu, 2012).\u003c/p\u003e \u003cp\u003eSecond, a sharp contraction occurred between 2011 and 2014, during which both harvested area and production declined significantly. The harvested area fell from 337,466 hectares in 2011 to about 126,490 hectares in 2014, while production dropped from 562,572 tonnes to approximately 99,010 tonnes during the same period. This decline represents the most significant structural shift in the dataset and likely reflects a combination of aging cashew tree plantations, limited access to improved planting materials, pest infestations, fluctuating market prices and possible revisions in FAOSTAT statistical estimation methodology (Aliyu, 2012; Akinwale \u0026amp; Esan, 2019).\u003c/p\u003e \u003cp\u003eThird, the period 2015\u0026ndash;2023 shows a gradual stabilization and partial recovery of the sector. Harvested area increased modestly from 131,529 hectares in 2015 to 171,383 hectares in 2023, although production remained relatively lower compared with the peak levels observed in the late 2000s. Overall, while cashew cultivation expanded significantly during the early decades of the study period, the sector experienced structural adjustments in the 2010s that have not yet been fully reversed.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003eCarbon Sequestration Potential of Cashew Cultivation in Nigeria\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e3\u003c/span\u003ea presents the estimated carbon sequestration potential associated with cashew cultivation in Nigeria between 1990 and 2023 under three scenarios: low, baseline and high sequestration rates. The estimates were derived by applying sequestration coefficients of 3.5 t C ha⁻\u0026sup1; yr⁻\u0026sup1; (12.8 t CO₂ ha⁻\u0026sup1; yr⁻\u0026sup1;), 4.5 t C ha⁻\u0026sup1; yr⁻\u0026sup1; (16.5 t CO₂ ha⁻\u0026sup1; yr⁻\u0026sup1;) and 6.0 t C ha⁻\u0026sup1; yr⁻\u0026sup1; (22.0 t CO₂ ha⁻\u0026sup1; yr⁻\u0026sup1;) to the annual cashew harvested area.\u003c/p\u003e \u003cp\u003eThe results show that cashew cultivation represents a substantial carbon sink within Nigeria\u0026rsquo;s agricultural landscape, although sequestration levels vary significantly across time due to changes in cultivated area. Under the baseline scenario, total carbon sequestration increased from 825 kt CO₂ in 1990 to a peak of approximately 6,311 kt CO₂ in 2010, reflecting the rapid expansion of cashew cultivation during the early decades of the study period. Following the contraction of harvested area after 2010, sequestration levels declined but stabilized in recent years, reaching approximately 2,828 kt CO₂ in 2023. Across the entire study period, the average annual sequestration levels are estimated at 2,668 kt CO₂ under the low scenario, 3,438 kt CO₂ under the baseline scenario and 4,584 kt CO₂ under the high scenario. These values illustrate the potential contribution of cashew plantations to climate change mitigation within Nigeria\u0026rsquo;s agri-food systems, even under conservative assumptions regarding sequestration rates.\u003c/p\u003e \u003cp\u003eThe sensitivity analysis highlights the significant influence of sequestration coefficients on total mitigation estimates. Under the low scenario, annual sequestration remains consistently below 5,000 kt CO₂, whereas the high scenario produces estimates exceeding 8,400 kt CO₂ during peak expansion years such as 2010. Despite these differences, the general pattern of sequestration closely follows the trajectory of cashew cultivated area, confirming that land-use expansion is the primary driver of sequestration dynamics in this context.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e3\u003c/span\u003eb presents the same sequestration scenarios in a publication-quality ribbon format. The shaded uncertainty band, spanning the full range between the low and high scenario bounds, clearly visualizes how the choice of sequestration coefficient amplifies or dampens estimated carbon uptake over time. The ribbon is narrowest during the early 1990s when cashew area was limited and widens substantially during the 2005\u0026ndash;2010 peak expansion period, with a spread of approximately 3,519 kt CO₂ between the low and high scenario estimates in 2010 alone. This widening underscores the sensitivity of national-level sequestration totals to coefficient uncertainty and reinforces the importance of the scenario-based approach. The post-2014 narrowing of the ribbon reflects the contraction and stabilization of cashew cultivated area and confirms that land-use extent remains the dominant driver of sequestration variability.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003eContribution of Carbon Sequestration to Offset Agri-food Carbon Emissions under Low, Baseline and High Scenarios\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e4\u003c/span\u003ea shows the estimated percentage contribution of carbon sequestration to offset agri-food carbon emissions under three scenarios: low, baseline and high sequestration potentials. The results indicate that the contribution of carbon sequestration to offset agricultural emissions varied substantially over time, ranging from 1.36\u0026ndash;9.85% (low scenario), 1.75\u0026ndash;12.70% (baseline scenario) and 2.33\u0026ndash;16.93% (high scenario). These variations reflect differences in sequestration capacity, land management practices and potential improvements in carbon capture efficiency.\u003c/p\u003e \u003cp\u003eAt the beginning of the study period (early 1990s), the contribution of carbon sequestration to offset agricultural emissions was relatively small across all scenarios. Under the baseline scenario, the contribution ranged from approximately 1.75% to about 5.41%, while the low and high scenarios ranged between 1.36\u0026ndash;4.20% and 2.33\u0026ndash;7.22%, respectively. As the years progressed toward the mid-2000s, the contribution of carbon sequestration increased significantly across all scenarios. The baseline scenario increased steadily to around 10\u0026ndash;11%, while the high scenario exceeded 14\u0026ndash;15% in some years. The highest contribution occurred when the baseline scenario reached approximately 12.70% and the high scenario peaked at about 16.93%.\u003c/p\u003e \u003cp\u003eHowever, after the peak period, a noticeable decline in the contribution percentages was observed across the three scenarios. The baseline contribution dropped from values above 11\u0026ndash;12% to approximately 3.94\u0026ndash;5.32%, while the high scenario declined to roughly 5.25\u0026ndash;7.09% in some years. In the later years (post-2015), the contribution values stabilize at relatively moderate levels. Under the baseline scenario, the contribution fluctuates between approximately 4.19% and 4.97%, while the low and high scenarios range between 3.25\u0026ndash;3.86% and 5.59\u0026ndash;6.63%, respectively. Overall, on average, cashew-based sequestration contributed about 2.67%, 3.44% and 4.58% of total agri-food emissions under the low, baseline and high scenarios, respectively, with peak contributions reaching approximately 9.85%, 12.70% and 16.93%.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e4\u003c/span\u003eb complements Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e4\u003c/span\u003ea by displaying the mitigation contribution ratios for all three scenarios simultaneously with overlapping area fills and clearly differentiated colour-coded lines, enabling direct cross-scenario comparison across the full study period. Three horizontal dashed benchmark lines at 5%, 10% and 15% serve as practical policy reference thresholds. Under the baseline scenario, cashew sequestration crossed the 5% threshold from the early 2000s onward and approached the 10% threshold during the 2005\u0026ndash;2010 expansion peak, while the high scenario briefly surpassed the 15% mark in 2010. The post-peak decline in all three scenario lines is conspicuous in Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e4\u003c/span\u003eb and the 2011\u0026ndash;2014 data anomaly period is visually highlighted by a shaded band, reinforcing caution in interpreting contribution estimates during that sub-period. The stabilization of all three lines in the 3\u0026ndash;7% range after 2015 demonstrates that, even at current cultivation levels, cashew plantations continue to provide a non-trivial but moderate carbon offset within Nigeria\u0026rsquo;s agri-food emission budget.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eThe observed increase in total emissions from Nigeria\u0026rsquo;s agri-food systems reflects the growing scale and complexity of the country\u0026rsquo;s food production and distribution activities. Similar trends have been documented globally, where agri-food systems have become an increasingly important contributor to greenhouse gas emissions. Recent global assessments indicate that food systems account for roughly one-third of total anthropogenic greenhouse gas emissions, with significant contributions arising from agricultural production, land-use change and food supply chain activities such as processing, transport and consumption (Crippa et al., 2021). These dynamics underscore the central role of agriculture in the climate change mitigation agenda, particularly in developing economies where agricultural expansion remains a key driver of economic growth and food security.\u003c/p\u003e \u003cp\u003eThe gradual increase in emissions observed over the study period likely reflects structural transformations within Nigeria\u0026rsquo;s agricultural sector. Rapid population growth, urbanization and changing dietary patterns have intensified demand for food, thereby encouraging agricultural expansion and increased use of production inputs. According to the Food and Agriculture Organization, agri-food system emissions have grown significantly in many developing countries due to rising production demands and expanding food supply chains (FAO, 2023). Nigeria, as Africa\u0026rsquo;s most populous country, has experienced substantial pressure on its agricultural systems to meet domestic food requirements, which partly explains the observed rise in emissions.\u003c/p\u003e \u003cp\u003eDespite the increase in total emissions, the consistent decline in per-capita emissions, falling from 1.17 t CO₂ per person in 1990 to 0.78 t CO₂ per person in 2023 suggests that population growth has outpaced the increase in emissions over time. Similar patterns have been observed in several developing economies where expanding food production systems generate higher total emissions while improvements in productivity and technological adoption gradually reduce emission intensity (Mr\u0026oacute;wczyńska-Kamińska et al., 2021). The declining trend in per-capita emissions may also reflect gradual improvements in the efficiency of agricultural production systems and evolving land-use practices. Nevertheless, the continued rise in total emissions highlights the persistent challenge of balancing agricultural development with environmental sustainability. As emphasized by the Intergovernmental Panel on Climate Change, sustainable land management and climate-smart agriculture are essential strategies for reducing emissions while maintaining food production (IPCC, 2021).\u003c/p\u003e \u003cp\u003eThe expansion of cashew cultivation observed between 1990 and 2010 reflects the growing importance of the crop within Nigeria\u0026rsquo;s agricultural diversification strategy. Nigeria is currently among the leading cashew-producing countries in Africa and plays an important role in the global cashew value chain (Mitchell et al., 2022). The rapid expansion in harvested area during the early years of the study is consistent with broader trends in global cashew production, where rising international demand for cashew kernels has encouraged increased cultivation in tropical producing regions. Several factors contributed to the growth of the sector during this period: favorable agro-ecological conditions and the adaptability of cashew trees to marginal soils facilitated expansion across multiple agro-ecological zones (Aliyu, 2012), while increasing global demand for cashew kernels created strong incentives for farmers to expand production to participate in export markets (Mitchell et al., 2022).\u003c/p\u003e \u003cp\u003eThe sharp contraction observed between 2011 and 2014 may be associated with several structural challenges within the sector. Previous studies have highlighted issues such as aging cashew tree plantations, limited access to improved planting materials, pest infestations and fluctuating market prices as key constraints affecting cashew productivity in Nigeria (Aliyu, 2012; Akinwale \u0026amp; Esan, 2019). The partial recovery observed after 2015 suggests a gradual stabilization of the sector, although production levels remain below the peak values recorded in the late 2000s, suggesting that productivity constraints remain a significant challenge.\u003c/p\u003e \u003cp\u003eThe results demonstrate that cashew cultivation has the potential to function as an important carbon sink within Nigeria\u0026rsquo;s agricultural systems. The magnitude of sequestration estimated in this study is consistent with findings from agroforestry research, which shows that tree-based agricultural systems can store significant amounts of carbon in both biomass and soils, with typical sequestration rates of 2\u0026ndash;9 t C ha⁻\u0026sup1; yr⁻\u0026sup1; depending on species composition, climatic conditions and management practices (Nair et al., 2009; Lal, 2020). The strong relationship between cashew harvested area and total sequestration highlights the importance of land-use dynamics in determining the mitigation potential of agricultural tree crops. Similar patterns have been observed in other tropical tree-crop systems, where increases in plantation area significantly enhance landscape-level carbon storage (Somarriba et al., 2013; Zomer et al., 2016).\u003c/p\u003e \u003cp\u003eThe relatively low offset capacity observed in the early years of the study (early 1990s) suggests that during this period, carbon sequestration mechanisms were still limited in their capacity to counterbalance emissions from agricultural production systems. Similar observations have been reported in global studies where early agricultural systems showed low mitigation potential due to limited adoption of climate-smart agricultural practices (Smith et al., 2014). As documented in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, the minimum contribution ratio under the baseline scenario was 1.75%, recorded in 1990, consistent with the limited cashew area (50,000 ha) at the start of the study period. Figure\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e4\u003c/span\u003eb visually confirms this early period suppression, with all three scenario lines clustering near the lower portion of the chart before the 5% benchmark until the late 1990s.\u003c/p\u003e \u003cp\u003eThe significant increase in the contribution of carbon sequestration toward the mid-2000s, where the baseline scenario climbed to around 10\u0026ndash;12% and the high scenario exceeded 14\u0026ndash;16%, suggests that enhanced carbon storage in soils and vegetation increased the system\u0026rsquo;s ability to offset agricultural emissions. Research has shown that improved soil management, agroforestry expansion and conservation agriculture can significantly enhance carbon sequestration, thereby reducing the net carbon footprint of agricultural production systems (Lal, 2004; Paustian et al., 2016). This peak period is clearly depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e4\u003c/span\u003eb, where all three scenario lines approach or breach the 10% and 15% benchmark reference lines between 2005 and 2010, with the baseline scenario reaching its maximum of 12.70% and the high scenario peaking at 16.93%, the highest values recorded in the entire study period (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe subsequent decline in contribution percentages after the peak period likely reflects increased agricultural emissions relative to the sequestration capacity, due to intensified agricultural activities, expansion of cultivated land and reduced effectiveness of carbon sinks. Agricultural expansion and increased fertilizer use are known to elevate greenhouse gas emissions, often outpacing the capacity of soils and vegetation to sequester carbon (IPCC, 2021). The stabilization of contribution values in the later years may indicate that the system has reached a balance between emission generation and sequestration potential and that the carbon sequestration capacity of the agricultural landscape has approached a saturation point, beyond which additional sequestration becomes more difficult without significant technological or management changes. Soil carbon saturation is a well-documented phenomenon, where soils reach equilibrium after prolonged sequestration efforts (Lal, 2018).\u003c/p\u003e \u003cp\u003eThe results demonstrate that although carbon sequestration contributes to mitigating agri-food carbon emissions, its contribution remains relatively modest compared to total emissions. Even under the high scenario, the offset potential rarely exceeds 17%, indicating that sequestration alone cannot fully neutralize emissions from agricultural production systems. This finding is consistent with global assessments which emphasize that while carbon sequestration is an important climate mitigation strategy, it must be complemented by emission reduction strategies such as improved fertilizer management, reduced deforestation and adoption of climate-smart agriculture (Smith et al., 2014; IPCC, 2021). The full distribution of contribution values across scenarios and years is summarized in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, which reports a mean baseline contribution of 7.03% (SD\u0026thinsp;=\u0026thinsp;3.15%) and Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e4\u003c/span\u003eb provides visual confirmation that even the high scenario line remains consistently below the 15% benchmark reference after 2014, underscoring the structural constraint that cashew area decline has imposed on Nigeria\u0026rsquo;s agricultural carbon offset capacity. Increasing the role of carbon sequestration in offsetting agri-food emissions will therefore require integrated land management approaches, including expansion of agroforestry systems, conservation tillage, restoration of degraded soils and improved pasture management (Paustian et al., 2016; Lal, 2018).\u003c/p\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003eLimitations and Future Research Directions\u003c/h2\u003e \u003cp\u003eThis study has several limitations that should be considered when interpreting the results. Carbon sequestration estimates were derived from area-weighted agroforestry coefficients calibrated using data from Togo, C\u0026ocirc;te d\u0026rsquo;Ivoire, Cameroon, and Benin rather than Nigeria-specific field measurements. Although agro-ecological similarities support the applicability of these coefficients, the lack of country-specific empirical data introduces some uncertainty beyond what is captured in the sensitivity analysis. In addition, a uniform sequestration coefficient was applied across the entire cashew harvested area, without explicitly accounting for variations in plantation age structure, tree density, soil conditions, or potential land-use changes within production systems. Also, the FAOSTAT cashew dataset exhibits a known structural break between 2011 and 2014, which may affect the consistency of estimates within this period. Finally, the MCt ratio represents a gross carbon offset and does not incorporate emissions associated with cashew production processes, indicating that the net mitigation contribution may be lower than reported.\u003c/p\u003e \u003cp\u003eFuture research should prioritize field-level carbon stock measurements in Nigeria\u0026rsquo;s major cashew-producing states to validate and refine the regional sequestration coefficients applied here. Additionally, household and farm-level economic analyses that quantify the cost-effectiveness of cashew-based carbon sequestration relative to alternative land uses would strengthen the policy case for targeted support to the cashew sector within Nigeria\u0026rsquo;s NDC implementation framework. Integration of remote sensing data to track cashew area dynamics with finer temporal and spatial resolution would also improve the accuracy of national-level sequestration accounting.\u003c/p\u003e \u003c/div\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eThis study assessed the relationship between agri-food carbon emissions and cashew-based carbon sequestration and evaluated the extent to which cashew cultivation contributes to offsetting emissions within the agri-food system over the period 1990\u0026ndash;2023. The findings reveal that while agri-food emissions increased by approximately 21% over the study period, cashew cultivation provided a meaningful but partial offset, with peak contributions reaching approximately 12.70% of agri-food emissions under the baseline scenario. The study identifies a three-phase trajectory in cashew-related sequestration that mirrors the evolution of cultivated area, confirming land-use extent as the primary driver of national-level cashew carbon storage. These findings highlight that cashew cultivation can function as a genuine but complementary climate mitigation strategy and that expanding cashew cultivation, particularly on degraded lands remains a viable option for enhancing Nigeria\u0026rsquo;s agricultural carbon balance. These findings have direct relevance for Nigeria\u0026rsquo;s Nationally Determined Contribution commitments under the Paris Agreement and suggest that a well-monitored expansion of cashew cultivation on degraded lands could qualify for inclusion in Voluntary Carbon Market (VCM) schemes, generating co-benefits for smallholder farmers and national climate targets simultaneously.\u003c/p\u003e \u003cdiv id=\"Sec19\" class=\"Section2\"\u003e \u003ch2\u003eRecommendations\u003c/h2\u003e \u003cp\u003eBased on the findings of this study, the following recommendations are proposed to enhance carbon mitigation within the agri-food system:\u003c/p\u003e \u003cp\u003e \u003cb\u003e1. Strengthening Carbon Sequestration Practices in Agricultural Systems\u003c/b\u003e \u003c/p\u003e \u003cp\u003eGiven that the study found carbon sequestration contributes only a modest proportion toward offsetting agri-food carbon emissions, there is a need to strengthen land management practices that enhance carbon storage. Practices such as improved soil management, conservation agriculture and integration of perennial vegetation should be promoted to increase the carbon sequestration capacity of agricultural landscapes.\u003c/p\u003e \u003cp\u003e \u003cb\u003e2. Adoption of Integrated Emission Reduction and Sequestration Strategies\u003c/b\u003e \u003c/p\u003e \u003cp\u003eSince carbon sequestration alone was found to be insufficient to fully offset agri-food carbon emissions, mitigation efforts in the agricultural sector should combine both emission reduction and carbon sequestration strategies. This may include improving fertilizer management, adopting low-emission farming techniques and enhancing soil carbon storage to reduce the overall carbon footprint of agricultural production systems.\u003c/p\u003e \u003cp\u003e \u003cb\u003e3. Expansion of Cashew Cultivation to Improve Carbon Sequestration\u003c/b\u003e \u003c/p\u003e \u003cp\u003eThe expansion of cashew cultivation should be encouraged as a strategy to enhance carbon sequestration within agricultural landscapes. Cashew trees, as perennial woody crops, have the ability to store carbon in both above-ground biomass and soil organic matter. Increasing the area under cashew cultivation can therefore improve the carbon sequestration potential of the agri-food system while also supporting farmer livelihoods. However, expansion should prioritize degraded or underutilized agricultural lands to ensure that increased carbon storage is achieved without causing deforestation or additional environmental degradation.\u003c/p\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate:\u0026nbsp;\u003c/strong\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication:\u0026nbsp;\u003c/strong\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials:\u0026nbsp;\u003c/strong\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests:\u0026nbsp;\u003c/strong\u003eThe authors declare that they have no competing interests\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; contributions:\u0026nbsp;\u003c/strong\u003eQ.A.O. conceived and designed the study, coordinated the overall research framework, and contributed to the development of the manuscript. O.P.B conducted the literature synthesis, designed the methodology and analysis. O.A contributed to the interpretation and discussion of results. K.A.A supported data compilation, contributed to the literature review and proof-reading of the manuscript. All authors participated in the revision of the manuscript, reviewed the final version critically for intellectual content, and approved the final manuscript for publication.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements:\u0026nbsp;\u003c/strong\u003eNot applicable\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAdjei V, Alormu MA. Cashew production as a climate change adaptation and mitigation tool for agriculture. Adv Earth Environ Sci. 2020;1(1). \u003c/li\u003e\n\u003cli\u003eAgboka K, Soro D, Agboka K. Carbon stocks in cashew plantations in Togo. Int J Environ Clim Change. 2025. \u003c/li\u003e\n\u003cli\u003eAkinwale TO, Esan VI. Cashew production in Nigeria: A review of production practices and constraints. Niger J Hortic Sci. 2019;24(1):1\u0026ndash;10. \u003c/li\u003e\n\u003cli\u003eAliyu OM. Development of improved cashew varieties in Nigeria. Afr J Plant Sci. 2012;6(3):69\u0026ndash;74. doi:10.5897/AJPS11.276 \u003c/li\u003e\n\u003cli\u003eBawa HS, Sharaai AH, Ab Rahim R, Sahrir S, Yuguda AU. Life cycle assessment of poultry production in Nigeria: A review of sustainability and evaluation studies. Chem Eng Trans. 2023;106:565\u0026ndash;570. \u003c/li\u003e\n\u003cli\u003eCrippa M, Solazzo E, Guizzardi D, Monforti-Ferrario F, Tubiello FN, Leip A. Food systems are responsible for a third of global anthropogenic greenhouse gas emissions. Nat Food. 2021;2:198\u0026ndash;209. doi:10.1038/s43016-021-00225-9 \u003c/li\u003e\n\u003cli\u003eFood and Agriculture Organization. Greenhouse gas emissions from agrifood systems: Global, regional and country trends 2000\u0026ndash;2021. Rome: FAO; 2023. \u003c/li\u003e\n\u003cli\u003eIntergovernmental Panel on Climate Change. Sixth Assessment Report (AR6). Geneva: IPCC; 2021. \u003c/li\u003e\n\u003cli\u003eIntergovernmental Panel on Climate Change. Climate change 2022: Mitigation of climate change. Cambridge: Cambridge University Press; 2022. \u003c/li\u003e\n\u003cli\u003eKabato W, Getnet GT, Sinore T, Nemeth A, Moln\u0026aacute;r Z. Towards climate-smart agriculture: Strategies for sustainable agricultural production, food security and greenhouse gas reduction. Agronomy. 2025;15(3):565. \u003c/li\u003e\n\u003cli\u003eKoffi JK, et al. Carbon dynamics in cashew plantations of C\u0026ocirc;te d\u0026rsquo;Ivoire. Int J Environ Clim Change. 2025. \u003c/li\u003e\n\u003cli\u003eKwiatkowski CA, Pawłowska M, Harasim E, Pawłowski L. Strategies of climate change mitigation in agriculture plant production: A critical review. Energies. 2023;16(10):4225. \u003c/li\u003e\n\u003cli\u003eLal R. Soil carbon sequestration to mitigate climate change. Geoderma. 2004;123(1\u0026ndash;2):1\u0026ndash;22. doi:10.1016/j.geoderma.2004.01.032 \u003c/li\u003e\n\u003cli\u003eLal R. Digging deeper: A holistic perspective of factors affecting soil organic carbon sequestration in agroecosystems. Glob Change Biol. 2018;24(8):3285\u0026ndash;3301. doi:10.1111/gcb.14054 \u003c/li\u003e\n\u003cli\u003eLal R. Managing soils for resolving the conflict between agriculture and nature. Eur J Soil Sci. 2020;71(1):1\u0026ndash;9. doi:10.1111/ejss.12848 \u003c/li\u003e\n\u003cli\u003eMitchell T, Keane J, Coles C. Trading up: Global value chains and the cashew sector in West Africa. J Agribus Dev Emerg Econ. 2022;12(4):567\u0026ndash;582. \u003c/li\u003e\n\u003cli\u003eMr\u0026oacute;wczyńska-Kamińska A, Bajan B, Pawłowski KP, Genstwa N, Zmyślona J. Greenhouse gas emissions intensity of food production systems and its determinants. 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Agric Ecosyst Environ. 2013;173:46\u0026ndash;57. doi:10.1016/j.agee.2013.04.013 \u003c/li\u003e\n\u003cli\u003eSteensland A, Zeigler M. Productivity in agriculture for a sustainable future. In: The innovation revolution in agriculture: A roadmap to value creation. Cham: Springer; 2020. p. 33\u0026ndash;69. \u003c/li\u003e\n\u003cli\u003eSuleiman IA, Anakhu EA. Modelling and evaluation of the effects of deforestation on carbon stocks in Nigeria: A case study of 36 states and the FCT. J Res Environ Earth Sci. 2023;9(4):180\u0026ndash;188. \u003c/li\u003e\n\u003cli\u003eVictor A, Noumi V, Zapfack L. Soil organic carbon in cashew agroecosystems of Cameroon. Am J Agric Biol Sci. 2020. \u003c/li\u003e\n\u003cli\u003eZomer RJ, Neufeldt H, Xu J, Ahrends A, Bossio D, Trabucco A, et al. Global tree cover and biomass carbon on agricultural land: The contribution of agroforestry to global and national carbon budgets. Sci Rep. 2016;6(1):29987.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-agriculture","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [BMC Agriculture](https://bmcagriculture.biomedcentral.com/)","snPcode":"44399","submissionUrl":"https://submission.nature.com/new-submission/44399/3","title":"BMC Agriculture","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Carbon sequestration, Cashew cultivation, Agri-food emissions, Climate change mitigation, Agroforestry, Nigeria","lastPublishedDoi":"10.21203/rs.3.rs-9456126/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9456126/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis study investigates the role of cashew cultivation in mitigating carbon emissions within Nigeria's agri-food systems. Using time-series data spanning 1990\u0026ndash;2023, the study analyzes trends in agri-food carbon emissions and evaluates the carbon sequestration potential of cashew plantations based on established agroforestry coefficients. Carbon sequestration was estimated as a function of harvested area and annual sequestration rates, while uncertainty in plantation characteristics was addressed through sensitivity analysis using low, baseline and high sequestration scenarios. The results show that agri-food carbon emissions increased considerably over the study period, driven by agricultural expansion and intensification. Although carbon sequestration from cashew cultivation also increased during periods of area expansion, it remained insufficient to fully offset emissions. On average, cashew-based sequestration contributed about 2.67%, 3.44% and 4.58% of total agri-food emissions under the low, baseline and high scenarios, respectively, with peak contributions reaching approximately 9.85%, 12.70% and 16.93%. These findings suggest that while cashew cultivation represents a significant carbon sink, its mitigation potential is constrained when considered independently of broader emission reduction efforts. The study concludes that cashew cultivation can play a complementary role in climate change mitigation within Nigeria's agri-food sector. Expanding cashew production, particularly on degraded lands and promoting climate-smart land management practices can enhance carbon sequestration while supporting rural livelihoods. However, achieving substantial emission reductions will require integrated strategies that combine sequestration with measures to reduce emission intensity across the agri-food system. Carbon sequestration values are modeled estimates derived from area-weighted coefficients based on Sub-Saharan African agroforestry literature and therefore represent generalized approximations rather than direct field measurements.\u003c/p\u003e","manuscriptTitle":"Role of Cashew Cultivation in Mitigating Carbon Emissions in Nigeria's Agri-Food Systems","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-05-04 13:22:04","doi":"10.21203/rs.3.rs-9456126/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2026-05-07T13:13:10+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"297452109399322755955547074565326424859","date":"2026-04-25T19:34:02+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-04-23T13:36:28+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-04-23T10:44:38+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-04-22T09:57:29+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-04-22T09:56:59+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Agriculture","date":"2026-04-18T11:34:22+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-agriculture","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [BMC Agriculture](https://bmcagriculture.biomedcentral.com/)","snPcode":"44399","submissionUrl":"https://submission.nature.com/new-submission/44399/3","title":"BMC Agriculture","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"983e723a-001b-4784-b12c-a1933a866867","owner":[],"postedDate":"May 4th, 2026","published":true,"recentEditorialEvents":[{"type":"editorInvitedReview","content":"","date":"2026-05-07T13:13:10+00:00","index":38,"fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-04T13:22:04+00:00","versionOfRecord":[],"versionCreatedAt":"2026-05-04 13:22:04","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9456126","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9456126","identity":"rs-9456126","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}