Conservation Agriculture Research Updates - October 2025

This study from Italy initiated in 1994 looks at the long term effects of CT and NT initially on Durum wheat but added Vicia faba cover crop in 2009 in half of each tillage treatment. They monitored  microbial biomass, soluble N, and enzyme activities (EA). Between 2009 and 2018, CT yields were on average 15% higher than NT, especially during high rainfall years, but NT increased SOC in the 0-30 cm soil depth and higher levels of soluble N, dsDNA, and EAs at 0-10 cm depth. Introducing cover crops over 4 years did not yield significant impacts.They conclude that adopting NT practices resulted in higher SOC concentration, enhanced soil biological activity, and improved biogeochemical cycles, emphasizing the positive impact of NT on soil health and sustainability.

This paper looks at ways to address the negative soil, environmental, and productivity issues of the major rice-wheat systems of the IndoGangetic Plains of South Asia that are grown on 13.5 mha and are crucial to food security. They evaluated 8 years of research that looked at farmer practices compared to 6 based on CA principles. They look at yield, economic returns, soil quality factors including chemical, physical and biological components and GHG emissions. They conclude that "CA practices and diversified crop rotations can address issues like falling crop productivity, reduced economic returns, soil degradation, and increasing environmental impacts in northwestern India’s traditional rice-wheat system. However, widespread adoption requires government policies, including C credit payments and guaranteed markets with supportive pricing."

This paper from Brazil assessed the effects of tillage systems and winter cover crops on soil carbon stocks and maize yields. Tillage treatments were conventional (CT), Reduced (RT) and No-till (NT). Cover crops included vetch, fodder radish, and black oats. Soil sampling occurred 4.5 years after the experiment was started. Samples were taken from 0-45 cm and measured for organic carbon and bulk density. NT had the highest SOC for all cover crops with CT the lowest. Vetch increased maize yield in CT and RT, but had lower C input than radish and black oats because of less biomass. NT systems led to the highest maize yields. Note that maize was not fertilized in this experiment. NT and cover crops was beneficial for environmental and agronomic benefits.

This paper from China looked at a 6-year field experiment that compared CA with CT on SOC fractions in a sandy soil. Compared to CT, CA increased particulate OC (POC) in the 0-30 cm soil depth and mineral-associated OC (MAOC) in the 0-20 cm depth. Tillage and soil depth had significant influences on the bacterial, fungal and protistan community compositions and structures. They conclude that the results strengthen their understanding of microbial functions in the accrual of SOC fractions, which contributes to the development of conservation agriculture on the Northeast China Plain.

This paper from Brazil looks at SOC storage, crop yield, and soil resilience from a long-term (26 year) experiment in Paraná State that was established in 1989. This LT experiment looks at a gradient of soil disturbance combined with contrasting fertilizer regimes. The main plots comprised the treatments related to soil management systems: 1) conventional plow-based tillage – CT; 2) minimum tillage (Chiselling replacing plowing) – MT; 3) no-till with one chisel plowing every three years – NTch; and 4) continuous no-till system – NTS. The sub-plots comprised full crop fertilization (FCF) for all crops and low crop fertilization (LCF) by suppressing K and P fertilization and maintaining N in broadcast application. SOC stocks significantly improved as the soil disturbance diminished, resulting in higher soil resilience indexes for NTS and NTch. The paper concludes that combining CA principles ultimately defined the potential for SOC sequestration.

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. 

The traditional rice-wheat-mung cropping system in North Bihar, India has experienced declining yields and water constraints. This paper looks at alternative tillage and crop establishment (TCE) practices to remedy this problem. Five different TCE practices were evaluated in on-farm experiments. The best yields were found with Zero-tilled direct seeded rice (ZTDSR) followed by Happy Seeder ZT wheat (HSZTW) and HS gram (HSG). This treatment also provided the highest net returns with this CA based system out-performing traditional systems.

This article reports uses on-farm data from France, Sweden and Romania  compared to field-experiments nearby to look at reduced tillage, organic farming and use of ley-grass periods into crop rotations to evaluate a more sustainable use of soils. No-tillage generally increased the mean SOC and total N contents of arable fields in comparison with ploughing but only in the 0-10cm layer. NT had no general affects on soil biology. In France, organic farming and ley-grass implementation into the crop rotation increased SOC and total N contents to the level of the no-tillage fields. The On-farm research gave similar results to the long-term field experiments. However, they suggest OFR is important and less costly than field experiments and also helps to exchange knowledge between scientists and farmers.

This paper from Hungary assessed the status of soil in an 18-year-old tillage experiment. looking at physical, chemical and biological properties in 3 tillage systems; No-till (NT), Shallow till (SC), and Ploughing (P). Their results show differences in bulk density (NT>SC) in 0-10cm depth, (NT>P in depths from 10-40 cm. NT had highest SOC in 0-10cm. Soil microbial respiration and abundance and biomass of earthworms was highest in NT. The conclude NT would be a good approach for sustainable soil tillage.

This long-term research, that was started in 2003 in Denmark, looks at continuous cereal cropping using NT versus moldboard ploughing (MB) combined with a fodder radish cover crop. Soil was sampled at the 0-10 and 10-20 cm depths. Various soil physical properties were assessed. Neither tillage or cover crop affected SOC stock in the 0-20cm depth. NT improved clay dispersibility (CD) and wet stability of aggregates (WSA) more in the 0-10 cm depth compared to plowing suggested as due to lack of disturbance. More results can be found in the paper. They conclude that the positive effects of NT on CD and WSA and the CC's on pore characteristics were more pronounced after 20 years than 10 years and conclude the value of longterm CA experiments.

This chapter in this reputable book discusses the issues of urbanization, soil degradation, and inappropriate farming practices and the pressure that results on soil, water,and vegetation and subsequently food and nutritional security, and at the same time providing ecosystem services and meeting the Sustainable Development Goals (SDG's). They discuss the role of No-till (NT) and Conservation Agriculture (CA) is reversing these negative trends. They cite long term experiments that provide information on improving soil health, SOC sequestration, GHG emissions, climate change mitigation, and resource use efficiency all impacting future food security. This chapter discusses the effect of NT/CA on soil health, nutrient stratification, SOC dynamics through modeling, SOC sequestration, GHG emissions, socio-economic condition in adoption and also suggesting the future perspectives on NT and CA.

This is a second 2022 article on cover crop benefits. It focuses more on replacement of summer fallow with cover crops in semi-arid regions and proposes this benefits soil health. It looked at the effects of long-term CC in no-till winter wheat - grain sorghum -fallow system. Fallow replacement treatments were spring-planted and included peas for grain as well as one-, three-, and six-species CC mixtures compared with summer-fallow. Half of each CC treatment was harvested for forage and the other half remained standing after termination. They conclude that simple CC mixtures and CCs managed for hay provide similar soil benefits as diverse CC mixtures or CCs left standing in this semi-arid environment.

This paper looks at the multitrophic network and its regulation of soil microbial carbon use efficiency (CUE) and SOC under different, long-term (15-year) tillage treatments. Conservation tillage (CT) enhanced microbial CUE, turnover, and SOC compared to traditional tillage (CK). Their results showed that the top-down control of protists in the soil micro-food web play an important role in improving microbial CUE under CT. By promoting the application of protists in targeted microbial engineering would contribute to the promotion of conservation agriculture and the improvement of soil C sequestration potential.

This study collected soil samples from paired farms that had used CA or conventional tillage (CT) and looked at tillage effects on physio-chemical properties including SOC by soil depth. SOC was higher in CA soils. But higher SOC was measured at depths of 0-10 cm compared to 10-30 cm under CA. In fact, soil depth had significant effects on most soil properties compared to tillage. The paper concludes that CA improved total SOC and its associated fractions, a finding relevant towards understanding effects of land management on carbon storage. However, challenges of competing residue use as feed, mulch, and fuel continued to impede mulching under CA systems.

This review looks at the global scientific production for CA and how it relates to mitigation of climate change. The used 650 articles published from 1995-2022. Publications on CA during this time have resulted in significant growth in number suggested as due to increased interest in this management system. They conclude "This analysis underscores the importance of CA in addressing climate challenges and offers insights into emerging research areas, such as regional adaptations and the long-term effects of no-till systems. The findings aim to guide future research and policy development in sustainable agriculture and climate mitigation."

Tillage and residue retention influence carbon storage within soil aggregates and particulate organic matter. This paper studied the effect of CA involving NT with surface residue mulch (NTM) in a maize-wheat system on particulate (POC) and mineral associated organic C (MinOC), C storage within aggregates and acid non-hydrolysable C (NHC) in a sandy loam soil and compared NTM to conventional tillage without residue. Results showed that the NTM improved SOC stocks by 23% more than CT in the 0-15cm. The results also showed that the effects of NTM were brought about by improved aggregate stability and C preservation inside macroaggregates of size >1 mm. They conclude that CA and NT plus residue leads to SOC sequestration in coarse textured soils. 

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.

SOC sequestration is an important tool for mitigation of climate change within the EU soil strategy for 2030. This review synthesizes existing knowledge, identifies knowledge gaps and provides research recommendations on trade-offs and synergies between SOC sequestration or SOC accrual, non-CO2 GHG emissions and N leaching related to selected soil management strategies using 87 peer-reviewed articles categorized under tillage management, cropping systems, water management and fertilization and organic matter (OM) inputs. This review provides guidance for policymakers and a framework for field experiments and model simulations.

This is a Springer Science book chapter that is part of a book series " Advances in Global Change Research ((AGLO,volume 78))". The chapter says that "agricultural research should focus on developing eco-friendly and sustainable crop production systems with higher crop productivity to achieve sustainable development goals. Also that conventional agriculture that has excessive tillage and crop residue removal is degrading soil health by losing SOC, losing good soil physical properties including compaction and negatively impacting soil biology. It concludes that "global policy initiatives should promote CA practices to conserve natural resources and better maintain soil health, as our sustainable future strategy for crop production."

This paper investigated the effects of tillage and nitrogen on yield and soil quality using a long-term, 18 year experiment. The rate of yield enhancement attributed to nitrogen addition varied from 8.2 % to 24.5 %, resulting in the most optimal yield under no-tillage with adequate nitrogen addition. Increased nitrogen inputs resulted in higher yield under no-tillage, particularly in wet years. Soil quality of no-tillage improved with nitrogen inputs, especially in terms of organic carbon and the availability of nitrogen and phosphorus, and increased yield. l. 

This paper evaluated the effect of CA management - no-till rice straw mulching on soil health parameters including SOC in the inter-rows of two citrus orchards in Spain. Various soil physical, chemical, and biological  were studied in the top soil layer (0-20cm) over 3 years. Their results showed that rice straw mulch resulted in reduced soil temperature that then resulted in higher crop root growth and increased soil macrofauna development and higher soil enzyme activities. The rice mulch also increased soil macroporosity and SOC levels showing that it enhances soil health in citrus orchards in Spain. However, compacted soils, the beneficial effects of straw mulching on soil health were still limited after three years of treatment.

This article from China looks at the long-term affect of tillage and nitrogen addition on yield and soil quality in rainfed maize. Their results show NT plus increased N resulted in higher yield especially in wet years. Over the 18 year period yield enhancement attributed to nitrogen varied from 8.2 to 24.5% with the highest yield under NT. They also found improvements in organic carbon, N availability and P was higher in NT treatments.

Soil sodicity is expanding in arid and semi-arid areas of the world. This paper examines the reclamation potential of CA based management on this soil issue. They look at NT, use of legumes in rotation, residue mulch (R+), and sub-surface drip irrigation (SDI)  for 3 years in a rice-wheat system in India. The paper provides detailed results on productivity, economics, water and N use efficiency, soil pH, exchangeable sodium percentage, extractable anions, soil organic carbon, soil solution cations. They conclude that CA practices can reduce sodicity and improve soil chemical properties for a profitable crop production.

This article starts out by saying farmers growing rice-wheat in the Indogangetic plains have problems adopting 100% but do adopt partial CA, especially NT in the wheat or other upland crop. So the paper looks at the impact of partial CA after 9 years. The treatments were tillage (main plot), crop residue management (sub-plot), and crop rotations (sub-sub-plot), respectively with permanent tillage or tillage only on rice, without or with all crop residues rice-legume combinations. Results show that post rice NT + residues in rice-chickpea-mung and rice-wheat-mungbean systems significantly increased SOC and carbon index from 0-15cm depth compared to the conventional practice after 9 years. Crop residue addition also increased SOC and C index compared to residue removal. Mean rice grain yield and sustainable yield index of the different systems after nine years were positively correlated with SOC storage.