Carbon Farming Research Articles

Evaluating the potential and eligibility of conservation agriculture practices for carbon credits

Carbon credits, a voluntary market mechanism to reduce greenhouse gas (GHG) emissions, can incentivize climate action. We evaluate the potential and eligibility of Conservation Agriculture (CA) practices for carbon credit generation in India under Verra's VM0042 methodology. Using farmer surveys and remote sensing data, we assess the eligibility based on the following conditions: Additionality Condition (GHG emission reductions to exceed legal requirements and the weighted mean adoption rate to be < 20% of area in the baseline), Yield Penalty Condition (no > 5% decrease in crop yields), and Quantitative Adjustment Condition (reduction in chemical fertilizer use by > 5%). Our analysis shows that CA has the potential to increase farmers’ carbon credit earnings by USD 18/ha and USD 30/ha in Bihar and Punjab, respectively. Punjab's ban on crop residue burning and the fact that > 20% of the area unburned limits the full economic realization of CA through carbon markets, decreasing potential income to USD 16/ha. A 60% increase in carbon prices from the current norm (USD 25) is required to encourage wider adoption of CA. Zero tillage of wheat in both Punjab and Bihar and reduction of nitrogen fertilizer overuse in Punjab fulfil all the conditions and are eligible for carbon farming projects.

The effect of carbon farming training on food security and development resilience in Northern Ghana

ABSTRACT Carbon farming has recently been advocated for as climate change and variability mitigation and/or adaptation strategy in global agriculture. In this study, we address an important research question of whether carbon farming training can improve household resilience capacity as well as food security by employing internationally standardized indicators. Household resilience capacity and its components are measured using the Food and Agriculture Organisation (FAO)’s resilience capacity index while the food security measures used include household and child food insecurity experience scale (FIES and CFIES), food consumption score (FCS) and household dietary diversity score (HDDS). We relied on doubly robust treatment effect estimators to account for potential selection bias and heterogeneity. We find that carbon farming training has no statistically significant effect on overall household resilience capacity. However, we find a large and statistically significant effect on key components of resilience (specifically, access to basic services, assets and social safety nets) and a marginal improvement in adaptive capacity. We also find statistically significant effect on FCS and HDDS but not for the other food security indicators (FIES and CFIES). Overall, the results suggest that agricultural training programs, particularly climate change adaptation capacity building initiatives, could improve important welfare measures in developing countries.

Carbon farming, overestimated negative emissions and the limits to emissions trading in land-use governance: the EU carbon removal certification proposal

This article conducts a qualitative governance analysis of the European Commission’s 2022 proposal for a certification framework for carbon removals (CRCF). It highlights potential challenges and legal implications—with a specific focus on carbon farming. While the European Union (EU) acknowledges carbon farming as an important strategy to offset residual emissions, such carbon removal activities are prone to reversals and models often overestimate their sequestration potential. The CRCF aims to account for these issues, but the analysis shows that the proposal may, in part, undermine international climate and biodiversity goals set by the Paris Agreement and the Convention on Biological Diversity. Key concerns include its failure to consider the normative hierarchy between emission reductions and removals mandated by EU and international law, the introduction of a temporary removal crediting system, the extensive delegation of powers to the Commission, the possibility that it may incentivise shifting effects, and its lack of alignment with other EU environmental policies. Additionally, the CRCF’s failure to restrict the use of carbon credits after certification increases the risk of double claiming of removal activities—and the proposal may open the door for to future integration of carbon removals into the EU’s emission trading scheme, which should be avoided for various reasons. As an alternative, member states should consider targeted subsidy schemes and regulatory instruments to navigate these challenges in carbon farming effectively.

Exploring the Impact of Digital Inclusive Finance on Agricultural Carbon Emissions: Evidence from the Mediation Effect of Capital Deepening

Carbon emissions from agriculture should not be underestimated. With the aim for carbon peaking and carbon neutralization and the help of digital inclusive finance, the effective reduction in carbon emissions in agriculture and animal husbandry production is crucial to achieving China’s carbon emission reduction goals. We used the balanced panel data of 31 provinces in China from 2011 to 2021 to study this issue. We empirically tested the impact, mechanism, and heterogeneity of digital inclusive finance on agricultural carbon emissions based on the systematic measurement of agricultural carbon emissions. The results revealed that (1) the development of digital inclusive finance has a significant inhibitory effect on agricultural carbon emissions, and it is an important path to reduce agricultural carbon emissions. (2) Through the intermediary effects’ analysis, it was found that capital deepening is an important transmission mechanism for the promotion of agricultural carbon emission reduction through digital inclusive finance. (3) Further analysis using the quantile regression model reveals that the impact of digital inclusive finance on agricultural carbon emissions is significantly negative at different quantiles. (4) Through the spatial Durbin model, digital inclusive finance has a space carbon enhancement effect. Finally, we put forward suggestions to promote the development of low-carbon agriculture by paying attention to the technical effect of digital inclusive finance, strengthening the connection and cooperation between various regions and promoting the carbon emission reduction role of capital deepening.

Carbon Farming and the Commission Proposal for a Regulation on a Certification Framework for Carbon Removals: a Legal Perspective

Abstract Carbon farming is a term associated with land-based practices, agricultural practices that aim at reducing emissions and sequestering carbon. These are, for example, agroforestry practices and practices that result in the maintenance and enhancement of soil organic carbon through the exploitation of the carbon cycle and the sequestration potential of soils. Given the evident links with climate change mitigation, the subject matter of carbon and carbon removals has seen important developments in the European Union (EU) in the past few years. This has culminated in the adoption of a Commission Communication on sustainable carbon cycles and a Commission Proposal for a Regulation on a certification framework for carbon removals. This contribution is meant to address the content and the potentially problematic aspects of the Commission Proposal from a legal perspective.

Analysis of the environmental and economic performance of common agricultural policy eco-schemes in soil organic carbon sequestration

The Andalusian olive grove in South Spain is employed as a case study to assess the environmental and economic effects of the green architecture (eco-schemes) of the Common Agricultural Policy in relation to low carbon agriculture under different soil management policy scenarios to support more efficient agri-environmental policy making. To do so, we adopted a multidisciplinary approach in which we used: (i) an integrated modelling framework comprising geographic information systems (GIS); (ii) the RothC model; and (iii) a cost-benefit analysis. Results show that eco-schemes provide a significant increase of soil organic carbon (SOC) relative to cross-compliance. Practices involving vegetation covers are more efficient than using pruning residues as mulching. SOC accumulation increases rapidly in the first five-ten years to slow down afterwards. The cost-benefit ratios of eco-schemes policy implementation are higher than one when only SOC is considered. Nonetheless, the inclusion of additional co-benefits has the potential to invert this scenario and enhance policy efficacy. Various insights on optimizing the design and application of eco-scheme efficiency are provided.

A novel Nash-based low-carbon implementation in agricultural supply chain management

The transition to low-carbon agriculture is seen as essential for accelerating the implementation of ecologically friendly and climate-smart agricultural supply chain management strategies. Success in these efforts depends on robust policy frameworks, effective stakeholder participation, and the availability of agricultural products to customers. This study introduces a conceptual and operational structure for the incorporation and management of an agricultural supply chain with a low-carbon scheme through the establishment of a collaborative market environment involving farmers, agricultural enterprises, and consumers. Within this framework, agricultural enterprises and farmers engage in a cooperative Nash game to determine the extent to which they are willing to employ low-carbon practices in response to collaborative market prices and government policies, including subsidies and carbon taxes. The Nash game yields a unique Nash equilibrium, suggesting the possibility of cooperative negotiations among the parties with the goal of improving their financial gains. The proposed model is applied in two Brazilian sugarcane supply chain case studies, integrating with traditional biorefinery mills to produce and market ethanol as a gasoline alternative. Our results suggest that (1) successfully allocating government subsidies and taxes motivates low-carbon adoption; (2) the government taxation policy stabilizes the low-carbon supply chain, improving stakeholder market pricing and consumer affordability; and (3) reduced cost gaps between low-carbon and non-low-carbon alternatives increase low-carbon adoption. As a result, this study provides fresh insights on the Nash collaboration of stakeholders in accordance with government policies to create a cleaner and more affordable agricultural supply chain market.

Implementation of marine CO2 removal for climate mitigation: The challenges of additionality, predictability, and governability

Achieving net zero CO2 emissions requires gigatonne-scale atmospheric CO2 removal (CDR) to balance residual emissions that are extremely difficult to eliminate. Marine CDR (mCDR) methods are seen increasingly as potentially important additions to a global portfolio of climate policy actions. The most widely considered mCDR methods are coastal blue carbon and seaweed farming that primarily depend on biological manipulations; ocean iron fertilisation, ocean alkalinity enhancement, and direct ocean capture that depend on chemical manipulations; and artificial upwelling that depends on physical manipulation of the ocean system. It is currently highly uncertain which, if any, of these approaches might be implemented at sufficient scale to make a meaningful contribution to net zero. Here, we derive a framework based on additionality, predictability, and governability to assess implementation challenges for these mCDR methods. We argue that additionality, the net increase of CO2 sequestration due to mCDR relative to the baseline state, will be harder to determine for those mCDR methods with relatively large inherent complexity, and therefore higher potential for unpredictable impacts, both climatic and non-climatic. Predictability is inherently lower for mCDR methods that depend on biology than for methods relying on chemical or physical manipulations. Furthermore, predictability is lower for methods that require manipulation of multiple components of the ocean system. The predictability of an mCDR method also affects its governability, as highly complex mCDR methods with uncertain outcomes and greater likelihood of unintended consequences will require more monitoring and regulation, both for risk management and verified carbon accounting. We argue that systematic assessment of additionality, predictability, and governability of mCDR approaches increases their chances of leading to a net climatic benefit and informs political decision-making around their potential implementation.

Agricultural limitations to soil carbon sequestration: Plant growth, microbial activity, and carbon stabilization

Soil carbon (C) sequestration is an important process for mitigating climate change while improving soil productivity. At the same time, it presents challenges for nutrient availability and changing agricultural practices. The aim of this study was to survey the challenges and limitations found on pioneering farms testing C sequestration using a Finnish network of farmers testing carbon farming practices. A combination of satellite monitoring, on-site measurements and soil analysis was used to quantify and evaluate soil physical, chemical, and biological quality indicators and plant productivity on 20 farms (40 fields). The indicators were assessed through a conceptual C sequestration model, classifying them into limitations for three stages of plant growth, microbial activity or C stabilization. Based on the results, there are limitations in all three stages: plant growth is constrained by crop choices which limit leaf area and sunlight capture, microbial processing of C is limited by poor soil structure and moisture stress, and C stabilization is limited by waterlogging and sulfur deficiency. These problems were found to be widespread, but not present on all the farms. Bringing all the farms to the levels of the best performing farms could reduce the considerable gap between potential productivity and C sequestration and that achieved in practice.

Toward Low-Carbon Rice Production in China: Historical Changes, Driving Factors, and Mitigation Potential.

Under the "Double Carbon" target, the development of low-carbon agriculture requires a holistic comprehension of spatially and temporally explicit greenhouse gas (GHG) emissions associated with agricultural products. However, the lack of systematic evaluation at a fine scale presents considerable challenges in guiding localized strategies for mitigating GHG emissions from crop production. Here, we analyzed the county-level carbon footprint (CF) of China's rice production from 2007 to 2018 by coupling life cycle assessment and the DNDC model. Results revealed a significant annual increase of 74.3 kg CO2-eq ha-1 in the average farm-based CF (FCF), while it remained stable for the product-based CF (PCF). The CF exhibited considerable variations among counties, ranging from 2324 to 20,768 kg CO2-eq ha-1 for FCF and from 0.36 to 3.81 kg CO2-eq kg-1 for PCF in 2018. The spatiotemporal heterogeneities of FCF were predominantly influenced by field CH4 emissions, followed by diesel consumption and soil organic carbon sequestration. Scenario analysis elucidates that the national total GHG emissions from rice production could be significantly reduced through optimized irrigation (48.5%) and straw-based biogas production (18.0%). Moreover, integrating additional strategies (e.g., advanced crop management, optimized fertilization, and biodiesel application) could amplify the overall emission reduction to 76.7% while concurrently boosting the rice yield by 11.8%. Our county-level research provides valuable insights for the formulation of targeted GHG mitigation policies in rice production, thereby advancing the pursuit of carbon-neutral agricultural practices.

Offset ratios and temporary contract designs for climate integrity in carbon farming

In this study, we examine how to enhance the climate integrity of carbon credits from carbon farming practices. The key requirements for climate integrity include permanence, additionality, and measurement and verification. Farmers are typically willing to make carbon contracts for a finite time only in voluntary markets or with the government and receive carbon credits to sell as offsets. This contradicts the requirement of the permanence of carbon sequestered in soils. To solve this problem and to facilitate greater participation by farmers in carbon sequestration, we show how temporary contracts can be made to address the issue of permanence by using offset ratios. The notion of the offset ratio refers to the share of one emission unit that one unit of temporary sequestered carbon replaces. Thus, the offset ratio transforms temporary sequestration to permanent emissions reductions. We propose the use of a discounting method to calculate the offset ratio. The ratio varies with the carbon contract length, employed discount rate, and assumptions about the evolution of the soil carbon stock. We apply this approach to cultivating catch crops for carbon sequestration on a north‒south gradient in Finland, Denmark, and France. We show that the offset ratio approach works well for every selected country. Carbon farming contracts are profitable for farmers provided that revenue under the contract exceeds that in the baseline. Profitability is highly dependent on catch crop cost, annual increase in soil carbon, and the discount rate. We apply offset ratios to assess the climate integrity of some existing crediting programs and find that the discounting method yields a lower offset ratio in almost all cases yielding a lower number of credits than launched in these programs.

REMOTE SENSING DATA APPLICATION TO MONITOR CARBON FARMING PRACTICES

Abstract. Carbon farming, a crucial strategy in mitigating climate change and promoting sustainable agriculture, requires precise monitoring to assess its effectiveness. This study explores the transformative potential of remote sensing data, with a focus on the fusion of Multispectral and Synthetic Aperture Radar satellite data, to enhance the precision and efficiency of carbon farming monitoring. Our research addresses the fundamental question: How can remote sensing data optimize the monitoring of carbon farming practices? This question drives our investigation into the practical applications of remote sensing technology in the context of carbon farming. In this article, the research is carried out in Lithuania, which is often covered with clouds or their shadows, so the application of various satellite images becomes even more meaningful. The study shows that the use of SAR image fusion for the identification of permanent meadows is appropriate and meaningful. The use of MSI image fusion for the identification of intermediate crops and stubble is also appropriate, but more research is needed that focuses on distinguishing these practices from other spectrally very similar practices.

Progress towards adopting low-carbon agriculture on peatlands for sustainable development in Indonesia

Indonesia, progressing towards sustainable development, faces the complex task of transitioning to low-carbon agriculture in peatlands, an essential part of broader sustainable objectives. Under the Paris Agreement, it targets a conditional 41% emission reduction, focusing on minimizing emissions from peat decomposition and fires within agricultural practices in peatlands. This paper explores the complexities and progress of low-carbon agriculture in peatlands, underscoring its significance in the larger sustainable development agenda. Our study reveals that current strategies to reduce carbon emissions in peatlands aim at restoring their natural waterlogged conditions. Yet, progress is hindered mainly due to an inadequate understanding of greenhouse gas emissions from peatlands and overlooking their unique features, which leads to overestimated emissions from agricultural use. For improved strategies, it’s important to analyze successful existing sustainable practices and enhance understanding of peatland ecology. Techniques like the “Water Management Trinity,” implemented since 1986, and eco-management emphasize the importance of using permanent water gates to maintain water levels optimal for both peat preservation and crop production. Over time, these practices modify peatland attributes, making emissions comparable to those from mineral soil, thus rendering low-carbon agriculture attainable. It’s vital for stakeholders to assess emissions with updated data, incorporating detailed information on peatland characteristics and emissions. The journey towards low-carbon agriculture in Indonesia’s peatlands is a complex endeavor necessitating the amalgamation of scientific research, sustainable practices, and socio-economic development. Adopting a holistic approach can strike a balance between agricultural productivity, peatland conservation, and climate change mitigation, fulfilling sustainable development goals in Indonesia and globally.

Investigating Drivers Impacting Carbon Stock and Carbon Offset in a Large-Scale Rubber Plantation in the Middle South of Thailand.

A large-scale rubber plantation in Southern Thailand is expected to capture a significant amount of carbon dioxide from emissions through carbon sinks in the vegetation and soil. The goal of this research is to create a carbon offset assessment for rubber plantations lasting for 30 years using a voluntary market contract approach. To evaluate the area of large-scale rubber plantations, this study evaluated major growing regions in five provinces in the middle-south region of Thailand (Nakhon Si Thammarat, Phatthalung, Songkhla, Satun and Trang) using an integrated RS-GIS technique that incorporated biomass allometric equations, soil series databases, and object-based classification. The classification of rubber plantation areas and the mapping of rubber stand ages were conducted to estimate the above-ground biomass of the rubber tree. Texture analysis was used in the rubber classification process, and normalised difference vegetation index (NDVI) was combined with texture analysis to separate vegetation areas from other land cover. Four groups of varying ages (1-6, 7-13, 14-20 and 21-30 years old) were evaluated for their capacity to generate carbon offsets. The equations of voluntary market contract revenue according to the contract method of the CCX were applied for this case study. This evaluation was used to estimate their annual value, total and net incomes in the carbon market price regarding the RGGI Allowance (RGA). Carbon offset income was then used to estimate the potential income (over a 30-year period) of the life of the contract. The results showed that the carbon stock potential of rubber plantations depended on the age of the trees and the soil carbon stock. The total carbon stock in the rubber plantations varied from 249.73 to 301.48 Mg C/ha (or equivalently 916.49 to 1,106.44 Mg CO2e/ha). Furthermore, the potential net income of the contract was estimated to be between USD5,378.32 and USD5,930.38 Mg CO2e/ha over a 30-year period according to the voluntary market contract revenue. These results suggest that the large agricultural land plot policy could create opportunities for carbon offsetting. The policy of large-scale rubber areas could be used as a tool and mechanism for farmers who are considering participating in carbon-crediting mechanisms. Then, farmers could use voluntary market contracts as a guide and foundation for their decision-making. The carbon offset credit strategy could assist Thailand in achieving its climate goals of transitioning to a low-carbon agriculture sector.

The assessment of carbon farming practices for the ecological vegetable growing system – a review

The assessment of carbon farming practices for the ecological vegetable growing system – a review

The impact of green and low carbon agricultural production on farmers’ income in minority areas: a case study of Y Town, Zhijin County, Guizhou Province

Developing green and low-carbon agriculture is an important and effective way to promote farmers’ income growth. Given the country’s “dual carbon” goal, the study of the impact of green and low-carbon agriculture on the income of farmers in ethnic minority areas is crucial for China to achieve the goals of socialist modernization and common prosperity. Taking Y Town, Zhijin County, Guizhou Province as an example, this paper uses the OLS regression method to empirically study the impact of green and low-carbon agricultural production methods on the income of farmers in ethnic minority mountainous agricultural areas based on the field survey data of 881 farmers. The regression results indicate that there is a positive correlation between green and low-carbon agricultural production and the household income levels of farmers; adopting green and low-carbon agricultural production technologies can effectively promote the growth of farmers’ household income. In addition, education level, health status, and the new rural social pension insurance have all had a significant effect on the income of rural households, however, due to the difficulty in establishing trust relationships, agricultural service outsourcing has reduced the household income level of farmers. As an example, the land transfer behavior in Y Town has no significant effect on increasing farmers’ incomes. Finally, it is recommended to increase fiscal and financial support as well as effectively enhancing farmers’ policy awareness and perception of green and low-carbon agricultural production technologies by improving farmers’ general trust and institutional trust by strengthening farmers’ agricultural education and skills training while cultivating technology-based farming. At the same time, it is necessary to break the geographical restrictions on land transfer scale and achieve moderate-scale land management while promoting the use and adoption of green and low-carbon agricultural production technologies, thereby improving agricultural production efficiency and product quality, and increasing the sustainable growth of farmers’ income. The main contribution of this study is to expand the research scope of green and low-carbon agriculture to ethnic minorities and mountainous agricultural areas.

Carbon farming as a future strategy for climate change: A literature review

Background: This research aims to know about carbon farming and strategies for storing carbon in the soil. Methods: The research method used is qualitative data analysis where this method describes the research conducted by the author by collecting data from scientific journals, books, and research journals. Finding: Respiration plants absorb carbon dioxide and give off oxygen. However, the balance of plants and humans/animals is now disturbed along with the massive and excessive use of fossil fuels. The result is global warming and uncomfortable conditions and health risks to humans and the planet globally. We are currently paying attention to how carbon dioxide is present in the air due to pollution and industrial waste. Various ways are done, including reducing the consumption of petroleum or fossil fuels. Instead of decreasing, the consumption of fossil fuels has not decreased but has increased along with the pace of industrialization in developing countries. Carbon farming is one method that can be a solution, with the principle that problems are solutions. Conclusion: Many strategies for storing carbon in the soil that we already know. As carbon is absorbed by the soil, the health of the soil will improve so that the health of plants will also increase and yields will increase.

Carbon Farming practices assessment: Modelling spatial changes of Soil Organic Carbon in Flanders, Belgium

Carbon sequestration in soils is a strategy to mitigate climate change and promote sustainable soil management. Since the European Union (EU) stimulates the reduction of greenhouse gases (GHG) from the atmosphere, the necessity to explore innovative approaches to sequester carbon in agricultural landscapes is becoming urgent. Carbon Farming (CF) has emerged as a promising program to mitigate climate change in agriculture but there is still a lack of agreement on which tools can be used to calculate Soil Organic Carbon (SOC) dynamics in this context. Using the RothC model a spatial analysis of SOC in the agricultural parcels of Flanders, Belgium was performed. Two among the various CF practices were simulated: a use of cover crops (CC) and the most common crop rotations adopted in the area, enriched with the use of cover crops. The performances of the model were evaluated and compared to other studies in areas with similar climate and environments. The selected CF practices can mitigate the carbon emissions from agricultural soils up to 60 % of the current projections. The most sensitive variables in the RothC model that affect the final total SOC, and thus determining the model outcome, are the Business As Usual (BAU) carbon inputs and the initial carbon content. For these variables the Pearson Correlation Coefficient with the change in SOC reached values of −0.78 and −0.50 respectively. To achieve net carbon sequestration in the agricultural soils of Flanders, Belgium, more effective solutions need to be evaluated. Furthermore, a larger amount and accessibility of data are required to reach better modelling performances.

Carbon Farming: Bridging Technology Development with Policy Goals

This paper conducts an in-depth exploration of carbon farming at the confluence of advanced technology and EU policy, particularly within the context of the European Green Deal. Emphasizing technologies at technology readiness levels (TRL) 6–9, the study critically analyzes and synthesizes their practical implementation potential in the agricultural sector. Methodologically, the paper integrates a review of current technologies with an analysis of EU policy frameworks, focusing on the practical application of these technologies in alignment with policy directives. The results demonstrate a symbiotic relationship between emerging carbon farming technologies and evolving EU policies, highlighting how technological advancements can be effectively integrated within existing and proposed legal structures. This alignment is crucial for fostering practical, market-ready, and sustainable agricultural practices. Significantly, this study underscores the importance of bridging theoretical research with commercialization. It proposes a pathway for transitioning current research insights into innovative, market-responsive products, thereby contributing to sustainable agricultural practices. This approach not only aligns with the European Green Deal but also addresses market demands and environmental policy evolution. In conclusion, the paper serves as a critical link between theoretical advancements and practical applications in sustainable carbon farming. It offers a comprehensive understanding of both the technological and policy landscapes, aiming to propel practical, sustainable solutions in step with dynamic environmental policy goals.

Effects of depth of straw returning on maize yield potential and greenhouse gas emissions.

Appropriate straw incorporation has ample agronomic and environmental benefits, but most studies are limited to straw mulching or application on the soil surface. To determine the effect of depth of straw incorporation on the crop yield, soil organic carbon (SOC), total nitrogen (TN) and greenhouse gas emission, a total of 4 treatments were set up in this study, which comprised no straw returning (CK), straw returning at 15cm (S15), straw returning at 25cm (S25) and straw returning at 40cm (S40). The results showed that straw incorporation significantly increased SOC, TN and C:N ratio. Compared with CK treatments, substantial increases in the grain yield (by 4.17~5.49% for S15 and 6.64~10.06% for S25) were observed under S15 and S25 treatments. S15 and S25 could significantly improve the carbon and nitrogen status of the 0-40cm soil layer, thereby increased maize yield. The results showed that the maize yield was closely related to the soil carbon and nitrogen index of the 0-40cm soil layer. In order to further evaluate the environmental benefits of straw returning, this study measured the global warming potential (GWP) and greenhouse gas emission intensity (GHGI). Compared with CK treatments, the GWP of S15, S25 and S40 treatments was increased by 9.35~20.37%, 4.27~7.67% and 0.72~6.14%, respectively, among which the S15 treatment contributed the most to the GWP of farmland. GHGI is an evaluation index of low-carbon agriculture at this stage, which takes into account both crop yield and global warming potential. In this study, GHGI showed a different trend from GWP. Compared with CK treatments, the S25 treatments had no significant difference in 2020, and decreased significantly in 2021 and 2022. This is due to the combined effect of maize yield and cumulative greenhouse gas emissions, indicating that the appropriate straw returning method can not only reduce the intensity of greenhouse gas emissions but also improve soil productivity and enhance the carbon sequestration effect of farmland soil, which is an ideal soil improvement and fertilization measure.