Conservation Agriculture Research Updates - March 2026

This review looks at the latest research on regenerative management strategies and the effects on soil organic carbon content and turnover, since the authors point out the importance of SOC for soil health. Regenerative strategies included CA, rotation, cover crops, organic management, biochar and agroforestry that all improve carbon sequestration. The conclusions are based on 283 studies that had both sort- and long-term field trials. They conclude that their research "outlines the benefits, challenges, and economic prospects associated with these strategies, emphasizing the significance of improving SOC management to promote soil sustainability and mitigate climate change consequences."

This paper starts out by saying that in Sub Saharan Africa (SSA) tillage and burning of residues is mostly used that causes soil erosion. Maize is also the major crop in smallholder diets. They used the APSIM model to simulate the productivity and protein yield of a variety of intercropping systems involving three crops (maize, cowpea and pigeonpea) under full CA practice relative to conventional tillage (CV) with the same intercropping system. The baseline scenario used daily climate data from 1997-2015 in Northern Mozambique. The results are given in the paper but the Authors conclude that "although under the CA system, there were ng declines in grain yields nevertheless, protein yields and overall productivity remained consistently higher under the CA system.

The Intergovernmental Panel on Climate Change projects an increase in temperature and the frequency of high-intensity rainfall events in the future in most parts of the world. NT was suggested by the UN missions Gap Report as a potential measure to mitigate the negative effects of climate change. This paper from Texas using the APEX model studies the effectiveness of NT in improving resilience of agricultural watersheds to extreme climatic conditions in comparison to conventional tillage (CT). Results showed that NT was significantly effective in reducing annual soil evaporation, surface runoff, and soil erosion and also maintaining rainfed corn yields compared to CT. During high rainfall events NT also minimized runoff and sediment erosion. The authors feel NT needs to be promoted in these climatic conditions.

This is another chapter in another 2024 book that has chapters on Principles of Agronomy for Sustainable Agriculture. Chapter 18 looks at soil conservation and negative issues of tillage and goes on to describe the role CA can play in reversing the issue of soil degradation when using tillage. They understand that adoption of CA will take time as farmers transition from conventional tillage. Literature has many examples of what is needed to accelerate adoption of this new management system. CA needs to address weed issues in the early years of adoption and suitable machinery availability for seeding. Use of cover crops in less intensive cropping systems in temperate climates are growing in acreage and supply the needed residue cover for CA.  

This is a chapter from the Cover Crops and Sustainable Agriculture book listed next that is devoted to cover crop use in conservation agriculture. This chapter looks at the issue of an expanding global population (10 billion by 2050) with a traditional farming system that uses intensive tillage and monoculture that is slowly degrading the soil, the environment and the ability to feed the future population, especially as climate change adds a further challenge for food production. This chapter provides information on cover crop mixes that are relevant for conservation agriculture to not only improve the benefits of a surface residue mulch needed for no-till systems but also a way to improve soil health vital for sustainable agriculture and future food security.

This study from China investigated the erosion processes and carbon dynamics across eroded slopes after adopting various conservation practices based on the data obtained from field experiments across the globe. Their results interestingly showed that adoption of CA compared to CT significantly did not reduce runoff but did lead to a significant reduction in sediment loss. CA also significantly increased soil organic carbon (SOC) in the top 10cm layer and reduced SOC loss. The results further highlighted the critical contribution of straw mulching in erosion control, soil organic carbon loss reduction, and soil organic carbon accumulation, while reduced tillage represented the least effective measure. 

This review explores a number of soil and water conservation practices, organic amendments, and agroforestry for specific soil types (7)  for the many diverse agroecological zones in Africa. In particular it looks at the role of soil through physical management to ensure resilience to climate change using long-term studies that are essential for improving soil structure, moisture retention, reducing erosion and enhancing SOM. However, adoption of these practices that improve resilience to climate change faces challenges due to diverse soils and ecologies, barriers to adoption and resource constraints. The authors advocate an integrated approach combining local expertise with scientific advancements and appropriate policy interventions.  to achieve the needed resilience.

This article reviews looks at conventional tillage (CT) and no-tillage (NT) systems on wheat yield since this has a direct effect on farmer adoption. They used a collected international database that showed NT is adaptable at all locations. Crop rotation was also important as was residue retention. The data was collected over the past 40 years and demonstrates the importance of NT in increasing the yield of wheat.

Conservation Agriculture scientists suggest that by not tilling the soil greenhouse gases can be reduced and help store carbon in the soil. However, other scientists question the benefits of CA for climate change. This paper based on a case study in Germany suggests that the full application of CA results in the carbon footprint from agricultural food production is significantly reduced and so helps mitigate climate change and make CA agriculture carbon neutral. Read the paper for full details.

This paper looks at maize yield impacts conservation tillage (CA?) from satellite data from 4 States of the US Corn Belt from 2008-2020. Data was obtained from several thousand fields with differences in climate, soil quality and irrigation status. Their results show overall that long-term adoption of CA increased rainfed maize yields by almost 10% in the area covered. When analyzing the variables, the increase in maize yields were associated with improved water infiltration and retention. But many fields that could benefit from no-till have not adopted yet. They can now strengthen the reasons and areas suitable for benefits from CA. Benefits can be obtained without negative crop yields in most cases. They did say in the paper that NT combined with cover crops amplified the benefits.

Strip tillage is gaining a lot of attention from farmers in the USA so I chose this article from a study in the USA (Alabama following Cotton) for readers of my CA newsletter. The objective of their study was to assess the effects of different tillage practices including strip tillage on soil pore properties. Undisturbed soil columns were collected during two seasons comparing ST with CT. Overall the study showed taht pore morphology can be affected by tillage and seasonal aspects associated with them.

This research looks at soil extracellular enzyme activities (EEA) on soil nutrient cycling using a meta-analysis with 3238 observations on the effects of NT and legume incorporation into a rotation system. Results show that NT significantly increased the activities of C, N and P acquiring, and oxidative enzymes. Combining NT with legumes did not affect on EEA's, but crop diversity did. They also identified climate, soil properties and agronomic practices as important factors affecting NT-induced changes in EEA's.

This paper looks at the long term effects of different tillage practices on sloping land in the hilly areas of NW Himalayas in India on runoff and soil erosion for three seasons - 2018-2020. There were 3 tillage practices, CT, MT (minimum), and NT. NT showed lower soil loss and erosion compared to MT and CT with CT having the highest values. For the same amount of rainfall, the reduction in soil loss was 39% and 68% in the CT and NT plots, respectively, at the highest growth stage in comparison to the initial crop growth stage. NT reduced erosion significantly compared to CT in extreme and normal rainfall events.

This article from China looks at the impact of adoption of CA on income. They surveyed 922 households in 5 provinces in 2023. The income effects vary by the adoption status of different CA practices. Farmer time allocation affects CA technologies adoption. Farm work is the main mediating variable, while off-farm work plays a moderating role between the yield effect and income. They write "The complex technology adoption chain inhibits farmers from increasing production and income, while the farmers' jobs in the non-agricultural sector have reduced this impact to a certain extent." They suggest that policies need to enhance technical training for farmers, improve markets, and provide more mechanized services in order to increase adoption.

This review assesses the effect of CA management on soil biological, chemical and physical properties. Results show that CA improves soil structure, enhances soil organic carbon sequestration, promotes microbial activity, increases water-use efficiency, and reduces erosion and nutrient losses. The paper also reports on environmental, economic, and social benefits of CA that include biodiversity conservation, reduced greenhouse gas emissions, improved yields, and increased food system resilience. They also look at the the socioeconomic conditions, institutional frameworks, and policy interventions that shape CA adoption and impact and the CA research gaps and future of CA directions.

This paper from Iran explores the factors that are responsible for adoption of CA in Iran since they suggest this system is important for environmental sustainability and resilience. They show it helps reverse soil degradation by improving moisture retention and increasing soil organic matter. Data were collected through questionnaires and analyzed using structural equation modeling. They conclude that "attitude and self-efficacy emerged as the most significant determinants influencing farmers' decisions to adopt CA. The information will provide valuable recommendations  for policy makers hoping to promote CA. 

This book chapter 16 from a 2024 published book on Greenhouse Gases in Climate Smart Agriculture covers the perspective on CA and GHG. It talks about how to feed a growing population when climate change is a major issue. Issues include burning of previous crop residues and loss of soil health and nutrients. This chapter discusses how CA can help with future food security. It concludes that "several studies have shown that CA practices reduce farm-related GHG emissions, improve soil health and structure, increase carbon sequestration, reduce soil erosion, and modify the microclimate" 

I included this book that was published in 2021 because it deals with the role of cover crops that are becoming more popular in modern agriculture and used in sustainable agriculture like conservation agriculture to provide the essential surface mulch needed to make no-till systems productive. This book is an encyclopedia of cover crop management by 2021. Papers in the 18 chapters indicate the long-term benefits for soil health, structure, water quality, nutrient contributions, soil biodiversity, air quality and climate change. The book looks at the "whys" as well as the "hows" for different locations and how to terminate them when needed. As part of a continuous no-till system, cover crops provide long-term biological, chemical and structural benefits. The resulting increase in soil organic matter means the agronomic crop yields benefit from better water infiltration and water holding capacity, greater availability of nitrogen and other nutrients, deeper rooting, and increased soil microbial activity in the root zone.

This paper on Africa highlights and discusses the current problems which include soil erosion, desertification, nutrient imbalances, acidity, salinization, deforestation, and soil compaction. The second part looks at the problems of soil and agricultural productivity and  human health, which resulted in loss of fertile land and biodiversity, increased greenhouse gas (GHG) emissions, nutrient depletion, loss of ecosystem services, malnutrition, and other human health issues. The third part proffers potential solutions to tackle soil degradation in Africa. They conclude that iintegrated approaches that promote sustainable soil management, such as conservation agriculture, crop rotation, agroforestry, afforestation, organic farming, and community engagement, would have a significant impact in resolving the menace of soil degradation.

This review looks at several ways to improve soil physical health. They define this as physical, chemical and biological characteristics. It includes structure, porosity,  and water retention. They include  soil management like CA, cover crops, and organic amendments. They also suggested precision farming and remote sensing as ways to monitor and manage soil health. They found they had constraints to undertake this and so recommend that future efforts focus on multidisciplinary research to better understand complex relationships.

Although Brazil's no-tillage system  provides efficient soil and water conservation practices, soil erosion can still occur during rainfall especially in sloping land. This paper looks at surface runoff and sedimentation during rainfall events for different cultivation systems. Three systems were evaluated: 1. A common local system where non-terraced catchment [NTC]), without mechanical runoff control practices; 2. Best management practices [BMPs]) that optimized crop rotation by incorporating a mixture of cover crop species in autumn and implemented contour farming practice; and 3. Terraced catchment [TC]), but with the same soil management practices as system 1. The results showed that sediment loss was lowest in the BMP (33%) and TC (63%) systems compared to NTC. They conclude that treatment 2 with contour farming and no-till, including a mixture of cover crop species, and constructing terraces was the best treatment. However, using and evaluating the combination of other conservation practices to control surface runoff, soil erosion, and the mobilization of nutrients and pesticides that could degrade or contaminate water is also recommended.

This paper from Italy is designed to better understand the relationship between soil organic matter (SOM) and the main farming systems found in the Po Valley of Italy. They developed a dataset of topsoil (0-20cm) SOM together with environmental and farming information collected from 597 locations (145 fields and 62 farms). Higher SOM contents were detected in Cambisols (3.11 %) and in field managed according conservation agriculture practices (3.22 %) as compared to other farming systems. Results also showed that the inclusion of fodder crops in the rotation and the use of no-tillage were two of the most effective practices for increasing and preserving SOM. 

This paper used 37 studies reporting 271 individual trials to provide a quantitative review regarding conservation agriculture related practices that mitigate soil erosion. Results showed that winter cover crops reduce cumulative seasonal (autumn-winter) runoff by 68% and soil losses by 72% compared with a bare soil. Conservation (non-inversion) tillage techniques alleviate cumulative seasonal overland flow by 27% and associated sediments losses by 66%, albeit there was evidence of publication bias. Intensive non-inversion tillage systems relying on repeated use of (powered) tillage operations appear to be the least effective for reducing both water and sediment losses. The best performing scheme against runoff would be a deep (non-inversion) tillage (−61%), while against erosion it would be a no-till system (−82%).

This book chapter reviews the benefits of CA and its potential to conserve fragile soil and water resources in semi-arid environments. In CA tillage practices are coupled with crop rotations and cover cropping where reduced soil disturbance results in at least 30% of residue remaining on the soil surface. Crop rotation coupled reduced tillage also enhances soil properties. CA also reduces evaporative losses and conserves groundwater while enhancing soil stability and reducing wind erosion in semi-arid areas. They conclude that developing management strategies to efficiently use irrigation water and capture precipitation and soil water in rainfed environments is crucial to avoid degradation of soil and water resources. 

This article emphasizes the importance of soil health for achieving agricultural resilience, food security and mitigating climate risks. It explains that ultimately it is farmer voluntary decision making that determines what steps are taken to improve SH. This research draws upon qualitative interviews with 91 farmers across three key agricultural states in the Midwest (Illinois, Indiana, and Michigan). They develop a more detailed understanding of farmers' views on SH, and why and how they manage to achieve it. Most farmers view SH favorably with only a few not familiar with what it means. Overall, farmers' perceptions of SH largely aligned with the scientific community's understanding of soils being a dynamic system, though farmers most dominantly defined SH by its biological component. They conclude that achieving better SH in agricultural production in the future will require engaging farmers in SH management by tailoring outreach and communication strategies to align with the perspectives and language farmers themselves use to conceptualize SH.