Enhancing soil organic carbon sequestration through conservation tillage: a comprehensive mega-analysis

Abstract

Soil organic carbon (SOC) is a critical component of global carbon cycling and a key regulator of soil CO₂ emission. However, the effects of agricultural activities, particularly tillage, on SOC sequestration are not fully understood. Here, we conducted a comprehensive mega-analysis of 24 individual meta-analyses to assess how conservation tillage practices, including no-till (NT), reduced tillage (RT), and mixed NT + RT, affect SOC sequestration. Overall, all conservation tillage types significantly increased SOC stocks, with RT showing the highest increase by 13.42% (effective size = 0.126), followed by NT 10.76% (0.102) and NT + RT 7.42% (0.071). Climate emerged as the dominant driver under NT, with the largest SOC increases in tropical and humid regions. Other influential factors included experimental duration, crop type, residue management, soil texture, pH, nitrogen fertilizer rate, and irrigation, all of which consistently enhanced SOC gains. SOC responses were strongest in surface layers (0–10 cm), in neutral and alkaline soils, and in coarse- to medium-textured soils. NT was especially effective in maize systems (15.57%, 0.145), the 0–10 cm soil layer (22.32%, 0.201), in neutral soils (12.87%, 0.121), and in alkaline soils (12.15%, 0.114). RT showed pronounced benefits in tropical climates, coarse and medium textured soils, and under nitrogen application and irrigation, with SOC increases up to 15.56% (0.145) in tropical regions, 18.90% (0.173) at a soil depth of 0–10 cm layer, 9.16% (0.087) in alkaline soils, 24.02% (0.215) in acidic soils, and 25.23% (0.225) in irrigated fields. Collectively, our findings demonstrate that conservation tillage substantially enhances SOC sequestration and that adopting context-specific conservation tillage practices can improve soil health while contributing to climate change mitigation.

Graphical abstract

Keywords

no-till / cropland / reduced tillage / response ratio / soil organic carbon

1 Introduction

Soil organic carbon (SOC) is fundamental to soil health, significantly influencing soil fertility, agricultural productivity, and greenhouse gas emissions (Lal, 2020). Changes in SOC sequestration are influenced by agricultural management practices such as tillage, residue retention, and fertilization, as well as by soil and environmental factors including soil pH and climate. Climate-smart agriculture practices, such as biochar application and conservation tillage (no-tillage: NT and reduced or minimum tillage: RT), have been proposed to enhance SOC sequestration while promoting sustainable food production. Tillage is a major agricultural practice with profound effects on SOC dynamics. Conventional tillage involves intensive soil tilling, which disrupts soil aggregates, accelerates organic matter mineralization, and contributes to soil degradation (van Wie et al., 2013; Kan et al., 2021). Under climate change, such disturbance further stimulates SOC decomposition, reducing the soil carbon sink capacity (Ise and Moorcroft, 2006). Therefore, identifying and promoting agricultural practices that increase SOC sequestration while maintaining agricultural products is critical for achieving sustainable agricultural goals.

Conservation tillage practices, including NT and RT, are widely recognized as effective climate-smart strategies for reducing soil carbon losses and enhancing SOC storage (Sun et al., 2011; van Groenigen et al., 2011). By minimizing soil disturbance (Salinas-Garcia et al., 1997), these practices foster beneficial soil biota such as fungi and earthworms (Lavelle et al., 1999; Briones and Schmidt, 2017), which play key roles in SOC stabilization (Liang and Balser, 2012). Numerous studies have reported increases in SOC stocks under NT and RT (Morugán-Coronado et al., 2020; Nunes et al., 2020; Payen et al., 2021; Lv et al., 2023). However, the magnitude and consistency of these effects vary substantially across studies (Liu et al., 2014; Morugán-Coronado et al., 2020; Lv et al., 2023), largely due to differences in climate, soil properties, experimental duration, nitrogen application, residue management, irrigation, and crop type. For example, some studies have found stronger SOC gains under NT in temperate than in tropical regions, while others observed contrasting results depending on soil texture or management history (Abdalla et al., 2016; Bai et al., 2019; Bohoussou et al., 2022). Despite these advances, a comprehensive synthesis that systematically evaluates how these interacting factors influence SOC responses to NT and RT remains lacking. This gap limits our ability to predict the conditions under which conservation tillage optimally enhances SOC, constraining its targeted application in sustainable soil management.

Meta-analysis has become a powerful tool in ecology and agricultural sciences for synthesizing results from individual studies and quantifying overall treatment effects (Hedges et al., 1999; Shakoor et al., 2021). Several meta-analyses have examined the impacts of NT and RT on SOC sequestration (West and Post, 2002; Morugán-Coronado et al., 2020; Das et al., 2022; Lv et al., 2023). For example, Luo et al. (2010) analyzed 69 experiments and found that SOC increased in the surface 10 cm but decreased in deeper layers (20–40 cm). Du et al. (2017) reported a 3.8% SOC increase under NT across 57 experiments while He et al. (2022) found an 8.1% increase at 0–20 cm north-east China. Similarly, Hashimi et al. (2023) found that NT increased SOC by 77.0% in the top 0–10 cm layer and Cui et al. (2024) synthesized 5230 paired observations from 446 studies and reported a global SOC increase of 9.9% under NT. Although these studies provide valuable insights, no prior effort has systematically compared and integrated results across existing meta-analyses to derive an overall grand effect size for NT and RT. Such a synthesis is essential to generate more accurate estimates and deepen understanding of conservation tillage impacts on SOC across diverse agroecosystems.

In this study, we conducted a mega-analysis by synthesizing data from multiple meta-analyses to quantify the overall effect sizes of NT and RT on SOC sequestration. Mega-analysis is an emerging approach that aggregates data from existing meta-analyses to yield a more comprehensive and statistically robust understanding of complex research questions (Hui et al., 2023; Kaur et al., 2023). We first compiled data from published meta-analyses addressing NT/RT effects on SOC. Using this data set, we then quantified the overall impacts of NT and RT relative to conventional tillage. We also examined how experimental conditions, soil properties, and agricultural practices modulated SOC responses. Specifically, our objectives were to 1) evaluate the existing meta-analyses on the effects of NT and RT on SOC sequestration; 2) quantify a grand response (RR, response ratio) summarizing the effects of NT and RT on SOC sequestration relative to conventional tillage; and 3) identify how soil properties (soil pH, texture, soil depth), experimental settings (experiment duration, crop type, climate, cropping system, crop rotation), and agricultural practices (N application rate, crop residue management, irrigation type) modulate SOC responses under conservation tillage.

2 Materials and methods

2.1 Literature search

A comprehensive literature search was conducted to identify meta-analyses examining the effects of conservation tillage practices, specifically NT and/or RT, on SOC sequestration. We search Web of Science and Google Scholar, using combinations of the following keywords “no tillage”, “reduced tillage”, “soil organic carbon”, “soil carbon”, and “meta-analysis”. The search included all relevant publications up to 2023. An initial screening identified 72 meta-analysis papers related to conservation tillage and SOC sequestration. Studies were then evaluated against the following inclusion criteria. 1) The study was a meta-analysis including NT and/or RT as treatment factors. 2) SOC was reported as a response variable. 3) The response ratio (RR) was used as the effect size, defined as RR = ln(Xt/Xc), where Xt is the mean of NT or RT treatments and Xc is the mean of conventional tillage. 4) Sample size, RR, and standard error or 95% confidence interval were reported or could be derived. Only meta-analyses that specifically examined NT or RT as treatment factors were retained. Studies that examined conservation tillage without distinguishing NT and RT were grouped as mixed NT + RT. After screening, 24 meta-analyses met these criteria and were included in this mega-analysis.

2.2 Data extraction and compilation

From each meta-analysis, we extracted the sample size (n), RR, and 95% confidence interval (95% CI: L₁, L₂). Data presented only in figures were obtained using Webplot Digitizer software (version 3.10). To examine the influence of various experimental settings, soil properties, and agricultural management practices on the effects of NT and RT on SOC sequestration, we also extracted n, RR, and 95% CI of RR for each of these categories. For instance, when studies classified soil texture as fine, medium, or coarse, these specific subgroup data were extracted when available.

2.3 Mega-analysis

We followed the analytical framework outlined by Kaur et al. (2023) for conducting this mega-analysis. Most meta-analyses reported SOC effects as RR values with 95% confidence intervals or as percentage changes. When confidence intervals were expressed as percentage changes, they were converted to RR using the following formulas: RR_L1 = ln(1 + L₁/100) and RR_L2 = ln(1 + L₂/100). If the mean RR was not explicitly reported, it was computed as RR = (RR_L1 + RR_L2)/2. The standard error of RR was estimated using the formula: SE = (RR – RR_L1)/1.96.

The grand mean of RRg was calculated using a weighted mean of RR_i:

(1){\mathrm{R}\mathrm{R}}_{\mathrm{g}}=\sum _{}^{}(n_i\cdot \mathrm{R}\mathrm{R}{}_{\mathit{i}})/\sum _{}^{}{\mathit{n}}_{\mathit{i}},

where RR_g is the grand response ratio of SOC across all studies, RR_i is the response ratio of SOC from the i-th meta-analysis study, and n_i is the sample size. We used sample size as a weight to mitigate the effects of very small variations (Sánchez-Meca and Marin-Martinez, 1998; Kaur et al., 2023; Hui et al., 2024). The weighted standard error was computed using the following equation:

(2){\mathrm{S}}_{\mathrm{e}}=\sum _{}^{}(({\mathit{n}}_{\mathit{i}}-1)\cdot {\mathrm{S}\mathrm{e}}_{\mathit{i}}^2)/\sum _{}^{}({\mathit{n}}_{\mathit{i}}-1).

The RR, standard error, and 95% confidence interval were originally expressed in natural logarithms and were converted to percentage changes for reporting using the following equation:

(3){\mathrm{R}\mathrm{R}(\mathrm{\%})=(\mathit{e}}^{\mathrm{R}\mathrm{R}}-1)\times 100.

The same approach was used to calculate the grand mean RR for different experimental settings, soil properties, and agricultural practices. In the experimental settings category, we considered climate (dry, humid, temperate, tropical sub-tropical), crop type (soybean, barley, legumes, maize, wheat, rice, others), experiment duration (< 5 years, 5–10 years, > 10 years), cropping systems (mono, double), and crop rotation. Soil properties included soil texture (fine, medium, coarse), soil pH (acidic, neutral, alkaline), and soil depth (cm). Agricultural practices included crop residue management (returned or removed), N application rate, and irrigation type. Subcategories within each category were harmonized based on the classifications mostly used in original meta-analyses. For instance, experiment duration was grouped into three subcategories: < 5 years, 5–10 years, and > 10 years, and soil pH included acidic, neutral, and alkaline subcategories. When meta-analyses adopted different subcategory criteria, we used weighted means to align them with the closest subcategories and applied Eqs. (1)–(3) to estimate the grand mean RR. Sigma Plot (15.0. SigmaPlot for Windows) was used to create figures.

3 Results

3.1 Overall effects of NT, RT, and NT + RT on SOC sequestration

We synthesized data from 24 meta-analyses published up to 2023 that reported the effects of NT and RT on SOC. Among these studies, sample size varied from 7 to 2007, with most between 100 and 500 (Fig. 1). Reported RR of SOC under NT varied from 5% (effective size = 0.053) to 40% (0.336), with the majority between 10% (0.096) and 20% (0.192). The grand mean RR of NT on SOC was 10.76% (0.102), ranging from 5.07% to 16.75% (0.049–0.154).

Ten meta-analyses assessed the effects of RT on SOC sequestration, with sample size from 16 to 468. The RR of SOC under RT ranged from 7.04% (0.068) to 60.12% (0.470). Overall, RT enhanced SOC by 13.42% (0.126) with a range of 1.81%–26.36% (0.018–0.234) (Fig. 1).

Only four meta-analyses reported the mixed NT + RT effects on SOC sequestration (Fig. 1). Sample size ranged from 12 to 2714, and RRs varied from 4.95% (0.048) to 18.84% (0.172). On average, NT + RT increased SOC by 7.42% (0.071), with a range of 1.58%–13.61% (0.015–0.127).

Comparatively, RT showed the strongest positive effect on SOC sequestration, with an average increase of 13.4%, slightly higher than NT (10.8%). Both practices significantly enhanced SOC accumulation, though RT appeared to be more effective overall.

3.2 Impacts of agricultural practices, soil properties, and experimental settings on the effects of NT, RT, and NT + RT on SOC sequestration

3.2.1 Effects of NT on SOC sequestration

The effects of NT on SOC varied across experimental settings, soil properties, and agricultural practices (Fig. 2). Regardless of crop rotation, NT increased SOC in both rotated and non-rotated systems. NT also increased SOC in both monocropping and double-cropping systems by 9.56% (0.091) and 8.95% (0.085), respectively. Across all crop types, NT improved SOC, with the greatest increase observed in maize systems 15.56% (0.144).

SOC accumulation under NT generally increased with experiment durations, reaching 12.07% (0.114) in studies exceeding 10 years. Except in subtropical regions, NT increased SOC across all climate zones (tropical, temperate, humid, and dry). The increase was most pronounced in surface soil (0–10 cm, 22.32%, 0.201), moderate in 10–20 cm (6.11%, 0.059), and negligible below 20 cm. NT increased SOC by 12.87% (0.121) in neutral soils, and 12.15% (0.114) in alkaline soils, but not in acidic soils. SOC under NT also increased in coarse and fine-textured soils.

When crop residue was returned, NT increased SOC by 11.96% (0.112), compared to 9.32% (0.089) when residues were removed (Fig. 2). SOC was enhanced by NT by 14.52% (0.135) in irrigated fields, whereas no significant effect was observed in rainfed fields. Across all N application rates, NT consistently increased SOC.

3.2.2 Effects of RT on SOC sequestration

RT also increased SOC under various conditions (Fig. 3). RT enhanced SOC in monocropping systems and showed significant positive effects only in experiments lasting more than five years. Across climate zones, RT consistently increased SOC, with the largest improvement in tropical regions (15.56%, 0.144). By soil depth, RT significantly enhanced SOC by 18.90% (0.173) in the 0–10 cm soil depth but had little effect below that depth. In alkaline and acidic soils, RT increased SOC by 9.16% (0.087) and 24.02% (0.215), respectively, with no effect in neutral soils. Positive effects were also observed in coarse and medium-textured soils. When crop residues were retained, RT increased SOC by 17.78% (0.163), compared to 7.21% (0.069) when residue was removed. SOC enhancement was particularly strong in irrigated fields (25.23%, 0.225), but not in rainfed fields. RT tended to increase SOC across all N application rates, with the greatest increase (13.24%, 0.124) observed at 100–250 kg N·ha⁻¹.

3.2.3 Effects of NT + RT on SOC sequestration

Mixed NT + RT generally increased SOC, particularly in shorter-term experiments (Fig. 4). SOC increased by 17.82% (0.164) in experiments shorter than five years and by 12.58% (0.118) in studies lasting 5–10 years but showed no effect beyond 10 years. Across climate zones, NT + RT enhanced SOC under both dry (14.74%, 0.137) and humid (14.17%, 0.132) conditions. SOC increases were consistent across soil depths, with approximately 22.95% (0.206) increase in both 0–10 cm and 10–20 cm soil layers.

4 Discussion

4.1 Relative effect of NT, RT, NT + RT on SOC sequestration

This mega-analysis, integrating results from 24 individual meta-analyses, provides the first comprehensive quantitative synthesis of how conservation tillage practices influence SOC sequestration. Overall, conservation tillage (i.e., NT, RT, and NT + RT) significantly increased SOC compared with conventional tillage. The greatest enhancement was observed under RT, which increased SOC by 13.42% (effective size = 0.126), followed by NT 10.76% (0.102) and the mixed NT + RT 7.42% (0.071). These results are consistent with previous reports demonstrating SOC enrichment under NT and RT systems (Aguilera et al., 2013; Zhao et al., 2017; Bai et al., 2019; Mondal et al., 2020; Wang et al., 2021; Kumara et al., 2023).

The enhancement of SOC under NT and RT is largely attributed to reduced soil disturbance, which preserves soil aggregates and enhances their stability, thereby reducing SOC decomposition and loss (Bai et al., 2019; Guo et al., 2020; Morugán-Coronado et al., 2020; Allam et al., 2022; Lv et al., 2023). Additionally, the physical protection of SOM under NT and RT also limits microbial mineralization and CO₂ emissions (Rahmati et al., 2020). Furthermore, conservation tillage retains more C input in the soil, particularly roots and crop residues, than conventional tillage, further contributing to SOC accumulation (Lenka and Lal, 2013; Zhang et al., 2017a; Li et al., 2021; Cui et al., 2024).

4.2 Context-specific benefits of NT on SOC sequestration

4.2.1 Experimental settings

NT significantly increased SOC across all crop types studied, with maize systems showing the largest increase (15.56%; 0.144), likely due to higher residue return. Both monocropping and double-cropping systems benefited (Das et al., 2022), but crop rotations with residue return produced greater SOC gains (Bohoussou et al., 2022; Cui et al., 2024). Reduced weed, pest, and disease pressures, coupled with increased organic matter inputs from crop residues, may explain these improvements. Long-term experiments (> 10 years) showed the greatest SOC increases (12.07%, 0.114) (Bai et al., 2019; Dong et al., 2021; Liu et al., 2023; Cui et al., 2024), underscoring that sustained NT is critical for SOC buildup. NT was most effective in tropical and semi-arid regions (Ogle et al., 2005; Bai et al., 2019; Kumara et al., 2023; Lin et al., 2023a), where favorable moisture conditions promote SOC stabilization. In contrast, its effect was limited in subtropical climates, likely due to higher SOC turnover and faster decomposition under warm, humid conditions (Mureva et al., 2018). Thus, long-term NT implementation in maize-based systems offers substantial potential for SOC enhancement, especially in tropical and semi-arid climates. In subtropical regions, however, NT should be combined with residue retention or biochar application to offset rapid SOC mineralization.

4.2.2 Soil Properties

SOC gains under NT were primarily confined to the surface soil (0–10 cm), with little effect below 20 cm. This pattern reflects surface crop residue retention and minimal soil disturbance (Nunes et al., 2020; Liu et al., 2023; Lv et al., 2023; Cui et al., 2024). Neutral and alkaline soils responded most positively, whereas acidic soils showed little to no improvement (Bai et al., 2019; Das et al., 2022; Lin et al., 2023b). The limited response in acidic soils resulted from constrained microbial activity and reduced organic matter stabilization (Zhang et al., 2017b). Soil texture also influenced NT outcomes: SOC increased in coarse and fine-textured soils, but not in medium-textured soils (Bai et al., 2019; Li et al., 2020; Das et al., 2022; Kumara et al., 2023). These results suggest that NT is most beneficial in neutral to alkaline soils with fine or coarse texture, while soil amendments such as lime or compost may be necessary in acidic or medium-textured soils to enhance SOC accumulation.

4.2.3 Agricultural practices

Residue management strongly influenced SOC responses under NT. Retaining crop residues enhanced soil aggregation and reduced carbon mineralization, where residue removal diminished these benefits (Liu et al., 2014; Kan et al., 2020). NT also increased SOC in irrigated systems but showed weaker effects under rainfed conditions, highlighting the importance of water availability (Bai et al., 2019; Das et al., 2022). Nitrogen application had a nonlinear mixed effect: moderate rates promoted SOC accumulation by stimulating plant growth and residue return, where excessive inputs (80 kg N·ha⁻¹) accelerated decomposition and reduced SOC (Blanco-Canqui et al., 2014). Overall, the maximum benefits from NT can be achieved through residue retention, adequate irrigation where feasible, and moderate N fertilization.

4.3 RT as the most effective practice under tropical and irrigated conditions

4.3.1 Experiment settings

RT significantly increased SOC in both monocropping and double-cropping systems (Das et al., 2022), with stronger effects observed after five years of continuous implementation. SOC accumulation peaked between 5 and 10 years of RT adoption and tended to stabilize in longer-term experiments, consistent with previous studies (Bai et al., 2019; Li et al., 2020; Dong et al., 2021; Das et al., 2022). This pattern suggests a diminishing marginal return as soils approach a new equilibrium state. RT was especially effective in tropical regions, where higher temperatures and precipitation accelerate residue decomposition and promote the formation and stabilization of SOC (Ogle et al., 2005; Bai et al., 2019; Li et al., 2020). These results emphasize that long-term and continuous application, preferably exceeding five years, with consistent residue inputs, is essential to fully realize the SOC sequestration potential of RT.

4.3.2 Soil properties

SOC improvements under RT were largely confined to surface soils (0–10 cm), consistent with earlier reports (Bai et al., 2019; Li et al., 2020; Bohoussou et al., 2022; Lv et al., 2023). The enhancement of SOC in topsoil is mainly attributed to reduced soil disturbance and improved soil aggregation, which protect organic matter from mineralization and erosion (Balkcom et al., 2013; Sheehy et al., 2015; Sauvadet et al., 2018). RT increased SOC across a wide pH range, particularly in acidic and alkaline soils, but its effects were less pronounced in neutral soils (Bai et al., 2019; Das et al., 2022). The stronger response in alkaline soils may be due to enhanced microbial activity facilitating carbon accumulation, while in acidic soils, RT may suppress microbial decomposition, thereby conserving SOC (Motavalli et al., 1995). Regarding soil texture, RT was most effective in coarse- and medium-textured soils, where reduced disturbance improved soil structure and enhanced carbon storage (Gicheru et al., 2004; Osunbitan et al., 2005; Gozubuyuk et al., 2014). Conversely, in fine-textured soils, which inherently possess higher SOC and aggregate stability, RT had limited additional effects (Li et al., 2020). Collectively, these findings indicate that RT performs best in coarse- or medium-textured soils and may require complementary measures to enhance SOC in neutral soils.

4.3.3 Agricultural practices

Residue retention greatly amplified the positive effects of RT on SOC by reducing erosion and slowing decomposition, thereby improving carbon retention (Liu et al., 2014; Bai et al., 2019; Li et al., 2020; Dong et al., 2021; Das et al., 2022). In contrast, residue removal substantially constrained SOC gains. RT performed better under irrigated conditions (Bai et al., 2019; Das et al., 2022), highlighting the importance of soil moisture availability for residue decomposition and SOC stabilization (Srinivasarao et al., 2014). Nitrogen fertilization showed a threshold effect: moderate application (100–250 kg N·ha⁻¹) promoted SOC accumulation (Bai et al., 2019), whereas excessive N application (> 250 kg N·ha⁻¹) reduced SOC by disrupting soil aggregation and stimulating microbial turnover (Blanco-Canqui et al., 2014). These findings identify RT as the most robust tillage strategy for enhancing SOC sequestration. For optimal outcomes, RT should be implemented in combination with residue retention, controlled irrigation, and moderate nitrogen fertilization.

4.4 Uncertainty and limitations

Although this study provides a comprehensive synthesis of the effects of NT, RT, and mixed NT + RT on SOC sequestration, several limitations should be acknowledged. First, the robustness of our mega-analysis is inherently constrained by the quality and scope of the underlying meta-analyses. A limited number of meta-analysis studies for certain response variables may reduce confidence in those estimates and introduce potential bias. Second, harmonizing mediator variables (e.g., nitrogen application rate, experiment duration, and climate categories) often requires re-categorization to achieve cross-study consistency. While necessary for synthesis, this process may have introduced inconsistencies among data sets. Third, partial overlap among primary studies included in multiple meta-analyses could have resulted in some degree of double-counting, potentially inflating overall effect sizes. Finally, publication bias within the original meta-analyses may also have influenced observed patterns. Taken together, these limitations call for cautious interpretation of our findings and underscore the importance of continued cumulative meta-analysis efforts, data transparency, and independent validation to refine global estimates of tillage impacts on SOC dynamics.

5 Conclusions

Drawing on evidence from 24 meta-analyses, this mega-analysis demonstrates that conservation tillage practices (NT, RT, and NT + RT) substantially enhanced SOC sequestration across a wide range of cropping systems and environmental contexts. All practices contributed positively to SOC gains, with RT emerging as the most effective, followed by NT and NT + RT. These findings reinforce extensive evidence supporting the role of conservation tillage in improving SOC sequestration and soil health. Importantly, SOC responses were strongly modulated by climate, experiment duration, cropping system, crop residue management, soil properties, and broader agricultural practices. This underscores the need to tailor tillage strategies to local conditions to maximize benefits. For NT, the largest SOC occurred under long-term implementation (> 10 years), high-residue crops (e.g., maize), residue retention, moderate nitrogen inputs, and favorable soil conditions (neutral to alkaline pH, fine texture). For RT, sustained application (> 5 years) combined with residue retention, adequate irrigation, and balanced nitrogen management proved most beneficial. In rainfed or resource-limited systems, integrating tillage practices with drought-tolerant crops or soil amendments can further enhance SOC accrual. Overall, these findings underscore that site-specific, integrated conservation tillage strategies are essential for strengthening soil health, increasing SOC sequestration, and advancing sustainable, climate-resilient agriculture.

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