Conservation Agriculture Research Updates - March 2026

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" 

This interesting article develops a conservation agriculture appraisal index (CAAI) as a standardized conceptual framework with defined thresholds that indicates the intensity and frequency of use of each CA core principle. This index was then applied to 100 farms in 4 wheat growing regions, with and without livestock and including rainfed and irrigated systems in Australia and Mexico to quantify CA adoption. CAAI score is the sum of the scores of each core principle, accounting for the percentage of the farm area and cropping season where CA is applied based on semi-structured interviews, questionnaires, and farm visits. Results show higher adoption in Australia than Mexico. No adoption of CA occurred when one of the core principles consistently scored zero within a year.

Despite CA being promoted and a possible solution for food insecurity resulting from climate shocks and soil degradation, adoption in Malawi is still low. This paper looked at social capital as a way of approving adoption. The interviewed 1512 smallholder farmers to find out how different social capital elements influenced farmer decisions to adopt CA. Factors that positively affected adoption were group membership, relations with leadership, land size, extension services, livestock ownership, and available credit. Full adoption of CA was limited compared to partial adoption. They conclude that better policy is needed to promote farmer organizations, community engagement, and training programs to enhance adoption.

This book on Regenerative Agriculture edited by Indian Agricultural Scientists has 16 chapters that look at the current knowledge of this term  that is recently been used as a solution for negative effects of climate change influenced by GHG emissions from burning fossil fuels and degradation of the natural resource base agriculture depends on. The book says Regenerative Agriculture involves the use of CA management practices such as no-till, mulch ground cover using previous crop residues (or the use of cover crops) and rotations. But it goes further and includes "integrating crops and livestock, improving animal welfare, improving social and economic well-being of communities, sequestering carbon, improving soil health, increasing yields and profit with a positive impact on food access or food safety regardless of farm size". The next article in this newsletter in a chapter from this book.

This is another adoption paper from the Mediterranean region -- Morocco, Spain and Tunisia. The study objectives were to investigate the sociocultural aspects of CA adoption, where they examined farmers’ understandings of ‘good soil management’ and a ‘good farmer’ identity. Crop rotation was a prominent concept cognitively tied to fertilizer application, bridging conventional and reduced tillage practices. CA farmers’ mental models of soil management were also more complex than conventional farmers. The ability to have good productivity and experience and knowledge were the most prominent aspects of farmers’ understanding of a ‘good farmer’. For CA farmers, environmental responsibility and innovation were important, whereas for conventional farmers, tillage and the use of mineral fertilizers, was valued more highly.

This is an interesting paper that compares the soil microbial biomass (SMB) and enzyme activity (EA) between no-till and integrated crop-livestock systems in tropical Brazil collecting soil samples from 0-20 cm depth. Their results show there are differences between agricultural systems but also sampling time and also interaction between these two items. More detailed results can be found in the paper. They conclude that there were significant seasonal responses to SMB and EA but more distinct responses to agricultural systems.

This chapter discusses the issues related to making both crop and livestock production more productive and efficient while cutting GHG emissions enough to limit temperature rise below 2C. The paper looks at agronomic practices for reducing GHG emissions, CA in relation to GHG emissions, grasslands and also peat lands as sink or source of GHG's. They cite the USA as an example of agriculture becoming more efficient while increasing crop and animal production by more than 30% while increase in GHG was 7% from 1997-2017.

The objective of this paper was to characterize soil water quality following cover crop (CC) under continuous wheat, grazing, tillage, and no-till practices in Texas. Treatments included CT and NT(with and without a CC and  NT with a grazed CC. Portable rainfall simulators were used to assess surface runoff water quantity and quality after CC implementation in a long-term no-till continuous wheat system. Cover crop treatments, both grazed and un-grazed, reduced the amount of runoff by 4–6 times compared to no CC.  Converting 12-year-old NT to CT reduced infiltration by at least 43 % and increased runoff by 58 % compared to long-term NT. They conclude that adopting NT, either alone, or long-term in combination with CC (either flash grazed or un-grazed) are potentially sustainable viable practices in semiarid regions that can reduce environmental contamination.

This paper provides information to society and decision-makers about the effectiveness of the adoption of conservation agriculture (CA) principles with zero tillage (ZT/CA) and integrated crop-livestock-forest (iCLF-CA) systems to mitigate soil erosion, the main agent of land degradation and productivity loss in Brazil. They estimate the potential loss by soil erosion with CT to be 3 billion tons in 2017. The economic impact, based only on replacement of nutrient losses, is estimated to be 15.7 billion US$ yr(-1). They conclude that the annual economic impact of the adoption of CA principles by controlling soil erosion was estimated at 1.5 billion US$ for ZT/CA in 2017. They also suggest the positive impacts of the adoption of CA principles in Brazil are the result of the determination of farmers, among many actors, and of the effectiveness of government plans and policies.

This is an interesting paper that looks at the conflicts between private interests and communal use of resources, for example the free grazing of crop residues. The objective was to assess the impacts of crop residue management on crop productivity in Burkina Faso. They use the AMBAWA model to simulate the flows of biomass and nutrients between crop and livestock systems at the village level scale for 4 types of farmers: subsistence-oriented crop farmers, market-oriented crop farmers, agro-pastoralists and pastoralists. The paper presents some interesting conclusions and suggests that the AMBAWA model can support discussion amongst stakeholders in order to co-design effective arrangements and practices for their sustainable use.

This paper was included because of the debate about use of residues in crop-livestock systems in Africa and their impact on adoption of CA. The area in Zimbabwe for this study is a semi-arid area where yields are low and residue biomass is limited. The paper looks at the economic tradeoffs and profitability of using residues for feeding the livestock or livestock using household surveys. The results show that a maize-macuna rotation can reduce tradeoffs of residues for mulch or feed. The results also show that The poverty effects of all considered alternative biomass options are limited; they do not raise income sufficiently to lift farmers out of poverty. Further research is needed to establish the competitiveness of alternative biomass enhancing technologies and the socio-economic processes that can facilitate sustainable intensification of mixed crop-livestock systems, particularly in semi-arid environments.

This research is conducted in the Mediterranean climate region of South Africa where the livestock sector constitutes a substantial contributor to the regional economy and where CA is integrated with livestock. Crop rotation with small grains and canola are combined with alfalfa and medics to supply feed for sheep. But this system raises concerns about livestock-crop competition but also nitrogen flows, on-farm nutrient balance, water pollution, soil acidification, biodiversity loss and impacts from climate change. This paper suggests that CA integrated agricultural systems serve as a buffer against environmental degradation caused by conventional agricultural systems.

This paper from South Africa looks at the production performance, soil greenhouse gas emissions, and soil carbon sequestration of different crop rotations. They measured nitrous oxide and methane fluxes over one year and analyzed 20 years of historical data on soil carbon sequestration, yields, fertilizer use, and wheat protein content. Results showed that rotations that contained legumes and livestock produced more wheat and canola yields and higher wheat protein. All systems showed an increase in SOC over the 20 year period. They concluded that "Legumes and livestock incorporation in crop rotations interact with nitrogen management. Most N2O emissions occurred after precipitation in the otherwise dry summer, making reduction difficult as minimal management activities occur over this fallow period.

This paper from South Africa explored soil fauna, physico-chemical properties, soil health, and multi-functionality management in 4 different land uses: Conventional (CT), livestock integrated (LA), conservation agriculture (CA) and natural grassland. Results showed that CT favored some nutrients, but soil of both LA and CA had physical and chemical properties indicative of good soil quality like low compaction, low C:N ratio and stable aggregates. Soil fauna abundance was more responsive to management than diversity. Ct where tillage is used had the lowest soil fauna and soil quality due to its disruption compared to no-tillage. They conclude that implementation of sustainable soil management practices that improve soil physical and chemical status will be beneficial for productivity but also for the promotion of important soil fauna, better soil quality and ecosystem multi functionality.

Conventional farming in Sub-Saharan Africa (SSA)  is resulting in soil degradation. This paper reviews current practices, challenges, and constraints to the adoption of CA in SSA to reverse this degradation. They show that CA is only adopted on 1.25% of cultivated land in SSA despite 2 decades of promotion. The paper lists 6 possible reasons for this lack of adoption of CA. They also suggest that adoption by smallholder farmers is also obstructed by socio-economic factors due to smallholder farmers’ focus on short term yield increases and their lack of access to markets, loans, and education. They conclude that wider adoption by smallholder farmers in SSA requires CA approaches that are downscaled to fit the existing tillage tools and the specific agroecological and socio-economic farm settings.

This paper suggests that agriculture needs to increase yields to future food security needs, but that conventional practices disrupt biodiversity in the soil needed for a number of ecosystem service functions. They also suggest that CA and crop-livestock systems promote biodiversity in agriculture. The objective of this paper was to assess how soil macro- and mesofauna in staple crops respond to different management systems through comparison of richness, composition and functional structure. NT coupled with rotations and various cover crop mixtures enhanced mesofauna numbers and diversity. They conclude that low-disturbance soil management, crop diversification and within crop habitat complexity helps preserve soil fauna diversity in staple crops.  

This article reviews the question "Can farmers in sub-Saharan Africa (SSA) increase yields and make food more available without using mineral fertilizer?" Supporters that say yes suggest that the principles of agroecology that rely on recycling, better efficiency and practices such as use of legumes and manure will mean more chemical fertilizer is not needed to raise yields. But this paper after extensive literature review suggests that more mineral fertilizer is needed in SSA. They put forward 5 reasons for this conclusion and can be found in this paper. They conclude there is a critical need for more mineral fertilizer in combination with the use of agroecological practices backed up by adequate policy support.

This integrated crop and livestock system  (ICLS) research evaluated the the impact of NT together with ICLS on soil health and soybean yield in Southern Brazil. Soil physical, chemical, and biological soil health indicators were measured over the short term (<5yrs) and long term (>10yrs) under ICLS with soybean in spring/summer and forage grazed by cattle in the autumn/winter. A Soil Management Assessment Framework (SMAF) was used for a soil quality index. Overall, the adoption of ICLS in association with NT (i) improved or maintained soil health, (ii) promoted soil carbon sequestration.

This article applies an endogenous switching regression model to a case study of 2296 wheat fields in Morocco, to provide evidence on the socio-economic impacts of residue retention. 30% and 60% plus of crop residues were retained respectively on 35% and 14% of wheat fields. These levels of residue retention led to 22% and 29% more yields, 25% and 32% higher gross margins and 22% and 25% more consumption of wheat, respectively. Residue retention is economically and biophysically beneficial even for owners of livestock as the monetary value of the additional grain yield more than offsets the cost of purchasing an equivalent amount of feed from the market—all providing good economic justification for residue retention. Development and/or import of alternative feed sources, introducing crop insurance, and raising the awareness of the economic, biophysical and environmental benefits of residue retention among farmers are needed.

This paper provides information to society and decision-makers about the effectiveness of of conservation agriculture (CA) principles with zero tillage (ZT/CA) and integrated crop–livestock–forest (iCLF-CA) systems as central policies to mitigate soil erosion, the main agent of land degradation and productivity loss in Brazil. The annual potential for soil erosion with intensive conventional tillage and monocropping, considering land use and cover in 2017, is 3.0 billion tons. The economic impact, based only on replacement of nutrient losses, is estimated to be 15.7 billion US$ yr−1. The annual economic impact of the adoption of CA principles by controlling soil erosion was estimated at 1.5 billion US$ for ZT/CA in 2017 and 0.5 billion US$ for iCLF-CA in 2015. They conclude that the positive impacts of the adoption of CA principles in Brazil are the result of the determination of farmers, among many actors, and of the effectiveness of government plans and policies.

This study uses Collembola numbers as a good indicator of improved soil properties following a change in land management. They looked at these springtail populations in systems with a history of CA and crop-livestock use in South Brazil. The samples were also evaluated for soil chemical, physical and microbiological properties. CA and CLI management varied in the association of different Collembola's -- epigeic in CA and hemiedaphic and edaphic ones in CLI but these differences were related to different soil conditions. They conclude that Collembola community structure and species diversity were modified by the soil management systems and suggest that the Collembola community may indicate changes across land management systems in conservation agriculture.