Conservation Agriculture Research Updates - March 2026

This paper from India and the NW IndoGangetic Plains assesses the system productivity and soil quality in a CA-based maize-wheat rotation as an alternative to rice-wheat. They compared no-till (NT) with conventional (CT); residue mulch (M+) versus no residue (M0); three N levels, 50 (N1), 100 (N2), and 150 (N3). The soil was sampled from 3 depths down to 30cm. Various soil properties were measured. Available P and K was higher in the M+ plots as expected. NTM+ increased soil microbial biomass C. The highest soil quality index was the NTM+ N3 treatment and the lowest CTM0, N1. Adding maize in rotation with rice improves soil quality.

This recent, available, valuable on-line paper emphasizes the critical nature of soils for agriculture and natural ecosystems that need to be protected. The paper describes how nature manages resources and management guidelines for "living soil". The paper promotes CA as a management system to achieve this protection. It explains why tillage is detrimental to soil health (SH) and how it destroys soil biological, physical, chemical, and hydrological properties. It concludes that in 2018/19, CA was practiced on more than 205 million hectares across more than 100 countries. That the impacts of climate change and tillage on food production and environmental degradation require the application of nature-based solutions as Conservation Agriculture.

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 chapter 3 in Advances in Agronomy starts by explaining the problems with meeting future food demand that is further complicated by climate change. The suggest that CA is a solution for meeting these challenges that include soil health, climate change, water scarcity, pollution, farm profit and human health. The paper reviews the published data in South Asia to assess the impact of CA in meeting these challenges. The results from several studies demonstrated that CA increased SOC and improved soil health parameters, mainly in the surface soil layer and also had a positive impact on nutrient availability in the soil. The chapter also outlines the knowledge gaps in soil health assessment and recommend that more research on soil health is needed in the future.

This paper analyzed two 6-year long component omission experiments on two different soil types (sandy and clay) in terms of soil chemistry, residue decomposition and arbuscular mycorrhizal fungi (AMF) colonization of maize roots. Soil chemical properties only differed across systems in the sandy soil mulched systems under no-tillage (NT) resulting in increased soil organic carbon levels, total nitrogen, and soil available phosphorus as compared to conventional tillage with no mulch or rotation (CT). Systems with NT and rotation resulted in highest AM fungal root colonization rate of maize at the clay soil location. Total plant N uptake was almost 2-fold higher in tilled and no-tilled systems with both mulch and rotations. They used  structural equation modeling to disentangle the links between cropping systems, soil chemical and biological properties, plant nutrient uptake, and maize grain yield. They conclude that a more holistic approach to cropping system assessment that includes a higher number of abiotic and biotic determinants is needed to evaluate the drivers of yield. .

This study used an Analytical Hierarchy Process to identify what farmers and experts assign as soil health indicators that they identify as useful in CA systems. Results showed that farmers give priority to soil nitrogen, SOC, and soil water content. Experts assigned soil organic carbon, soil water content, soil respiration, and soil microbial biomass. Both farmers and experts prefer no-till and reduced tillage to enhance soil health. They conclude that their results were useful to inform policy makers to support no-tillage crop management and would also be useful for crafting a soil health policy for transitions to sustainable and healthy ecosystems.

This paper looks at nitrogen (N) rates and residue management in a wheat crop on soil biological and chemical properties. Different combinations of N fertilizer rates, tillage, and residue management practices for wheat were investigated. N was 75 and 10% of recommended. Tillage treatments included CT, rotoseeder (RS), Happy Seeder (HS) with various residue treatments with rice residue removed  or retained R0, R50(50%) and R100. The results showed that N-100 and HS +R-100 increased wheat yield, chemical and biochemical properties except polyphenol oxidase and peroxidase. The HS picks up loose rice residue before planting no-till and then placing the residue on the soil as a mulch and so allows seeding into loose residue using fixed openers. 

This is another article looking at CA combined with agroforestry (CAWT) in smallholder farming in Kenya. CAWT is an agroforestry system that integrates legume trees and shrubs into cropping fields under minimum soil disturbance and tillage. The paper looks at key soil quality indicators (SQI) under CAWT. The research assesses the effects of CAWT components; tillage (CT or NT), leguminous trees/shrubs (Calliandra calothyrsus, Gliricidia sepium and Cajanus cajan), and their inter-row spacing (1.5 m, 3.0 m or 4.5 m) on SQI in the dry-land agroecosystems of eastern Kenya. They conclude that a shift towards CAWT showed evidence of improving soil quality, nutrient availability and increasing soil nutrient thresholds that can potentially support maize production.

The goal of this study was to look at the relationship of soil CO2 emissions with soil physicochemical properties from soils tilled differently in a winter wheat, summer maize rotation in China. This 4 year trial compared conventional till (CT) with no-till (NT). Cumulative soil CO2 emissions were reduced by 28.7% in maize and increased by 9.0% in wheat under NT as compared to CT. On an annual scale, the cumulative CO2 emissions were decreased by 20.5% in NT as compared to CT. NT improved the above ground biomass by 7.74% and 6.44%, and grain yields by 10.2% and 4.49% for maize and wheat, respectively. They conclude that NT can be extensively used as an eco-friendly cropland tillage practice based on its positive effects of reducing CO2 emissions and increasing crop yields.

This is another fungal community paper affected by management practices from India. It also looks at soil chemical and physical properties. It looked at various climate smart agriculture (CSA) scenarios based on CA and compared with CT in rice-wheat systems. There were 6 scenarios with CT, NT and +/- mungbean in rice-wheat and maize-wheat systems. The first 4 scenarios were flood irrigated and the last two with a subsurface drip with N as fertigation. Soil samples from 0-15cm were taken for fungal community composition. The data showed a higher Shannon diversity index of 1.47 times and a Simpson index of 1.12 times in maize-based CSA scenarios (ScIV and ScVI) compared with rice-based CSA scenarios. Soil physical, chemical, and biological properties were found better under CSA-based practices, which also increased the wheat grain yield and system yield and hence play an important role in sustaining soil quality/health.

This article was selected because it covers crop rotation (CR), one of the pillars of CA, affects on soil organic carbon (SOC). The study used 513 pairwise data from 167 global studies and did a meta-analysis to look at the role of CR on SOC content. Their results showed that CR overall enhanced SOC content by 6.6%. SOC content increased more in regions with intermediate mean annual temperature and precipitation. CR had greater impact on SOC in neutral soil pH, loamy texture and medium levels of initial SOC and total N. CR also performed better for SOC in soybean -based cropping systems with more rotation cycles, longer rotation length, medium N use, and where NT, residue retention, and organic fertilizer was used. They concluded that their study helps establish and manage site-specific CR systems that could enhance SOC in agroecosystems, ultimately facilitating carbon neutrality.

This paper highlights the importance of soil health and reviews the literature on the role of CA in improving soil health. They suggest that conventional agricultural practices cause deterioration in soil quality, increasing its compaction, water erosion, and salinization and decreasing soil organic matter, nutrient content, and soil biodiversity, which negatively influence the productivity and long-term sustainability of the soil. They conclude that CA can reduce the negative impacts of conventional agricultural practices on soil health while conserving the production and provision of soil ecosystem services.

This paper explores the impact of Climate Smart agricultural practices (CSAP) on farms in Haryana, India. They looked at ZT, residue retention and crop diversification and measured soil chemical and physical properties from 0-20cm, and GHG's comparing CSAP to conventional (CP) grown with wheat. Of the 70 farmers, 22 followed CSAP's and 48  CP's. Results showed that soil pH was lower (7.76) for CSAP farms compared to conventional practices (7.99). Soil carbon in CSAP was also higher as were total organic carbon stock and total carbon compared to CP. CA registered similar to 31% higher soil quality index over CP and wheat yields were higher. GHG emissions were similar to 63% higher in CP compared CSAP. CSAP not only improves soil carbon pools, but also improves the overall quality of the soil.

Soil health has become a foundation for sustainable goals associated with mitigation of climate change and reversing soil degradation and loss of biodiversity. There is also an array of indicators of soil health but what are the key indicators important for soil health outcomes and ecosystem functioning? This paper proposes and integrated approach to assess soil health.They list important key indicators because of their position in the soil food web and linkages to key soil processes. They recommend that future soil health assessments directly measure soil organisms in conjunction with indicators that reflect key ecosystem functions. 

This paper looks at the long-term effects of CT and NT tillage on chemical and physical mechanisms for SOC stabilization and accumulation in soils in after 23-years of continuous NT in southern Brazil. Data was collected from soils sampled from 0-100 cm depth and used soils from native vegetation (NV) as a check. When NV was converted to agriculture SOC stocks decreased by -33%. A comparison of NT and CT showed that NT resulted in higher SOC stock in the 0-5 and 5-10 cm soil layers and higher SOC in the entire topsoil (0-20cm). Below that both tillage systems had similar SOC levels. Adoption of NT increased the proportion of large macroaggregates in the 0–5 cm soil layer, resulting in a greater mean weight diameter (MWD) than under CT. They conclude that the pathway for SOC accumulation in the topsoil of NT is influenced less by selective preservation but driven by the maintenance of labile organic compounds, a process achieved by the low turnover of large macroaggregates in the NT system. 

This paper looked at 8 integrated crop management (ICM) practices for 6 years in a direct seeded rice-NT wheat rotation. There were 4 treatments with traditional practices and 4 with CA practices; residue retained and not retained treatments; raised bed and flat treatments. The CA-based treatments outperformed the CT practices for yield, soil quality index, and reduced carbon footprints. They conclude that the CA-based ICM practices proved to be environmentally safer and cleaner and can sustain the food and soil security of the extensive rice-wheat rotation under South Asian ecologies.

The paper stats by explaining the negative impacts of conventional management on degradation of soils and loss of soil health. The research looks at ways of reversing soil degradation using CA in a long term experiment (after 8 years) with 4 cropping systems, and three tillage systems; CT, RT and NT. Soil samples were collected from 3 soil depths; 0-10, 10-20 and 20-30 cm depths and data collected on soil chemical, physical, and biological properties in a Vertisol in Central India. @0 soil properties were used to calculate soil quality indices (SQI). The paper lists the results of this research. They conclude that the soil quality index was significantly highest in NT, followed by RT and CT at all soil depths. CA based practices favoured carbon storage, lowered carbon emission, foot print and soil quality compared to conventional farming. 

This study in DR of the Congo looked at 1) changes in soil chemistry and biology after using CA; 2) assessed the use of cowpea yield under CA compared to conventional (CT); 3) evaluated differences in soil chemistry, biology, yield under CA compared to CT in smallholder farming. Some results showed CA had more earthworms, more soil P and K, and double cowpea yields. They conclude that CA contributes to soil health and food security in this country.

This is a review article that discusses the importance of conservation agriculture as a long term approach for sustainable food security and a way to reverse issues of depletion of natural resources caused by long-term us of traditional tillage. The paper discusses the benefits of CA for improving the soil physical, chemical and biological properties and reversing SOM decline. They suggest that one sustainable cropping method that may reverse soil erosion, increase crop output, and improve the socioeconomic status of small landholder farmers is conservation agriculture (CA). The paper highlights the benefits and limitations of CA and various challenges in the adoption of CA.

This paper looks at organic vegetable systems and the use of agroecological service crops (ASCs) terminated by a in-line roller crimper (RC) in Southern Italy. Two ASCs winter cereal/legume-based mixtures were terminated by RC (ASC–RC treatment) and as green manure before organic tomato and compared with two tilled controls without ASCs. Despite the results on tomato yield, agroecological management seems a promising strategy to improve soil quality in a long-term perspective, supporting soil metabolic activity and improving its self-regulating capacity. 

This study looks at the potential impact of drought predictions on a faba bean crop, and evaluates the adoption of conservation tillage practices to reduce this effect in dryland areas of Spain. It sampled a long-term trial that was started in 2008 and looked at soil water storage (SWS), crop productivity and mineral nutrition, plant ecophysiology and biomass quality, as well as the colonization of roots by arbuscular mycorrhizal fungi (AMF) and symbiotic Rhizobium bacteria. It sampled the non-tillage (NT), reduced tillage (RT) and traditional tillage (TT)- and rainfall reduction treatments. The percentage of biomass yield reduction by rainfall exclusion was 30% for NT, 50% for RT and 20% for TT. They conclude that, despite no effect on soil water storage, in the conservation tillage systems the increase in the mycorrhizal colonization in roots, particularly under NT, could be beneficial for plants to face drought stress. However, in a scenario of reduced rainfall it will be necessary to invest more resources in weed control under RT.

This paper looks at low soil disturbance system on deep soil functioning. They compared the soil bacterial communities and physicochemical parameters across 3-m deep soil profiles in a Mollisol of Northeast China at the end of the dormant season after 10 years of farming under conventional tillage without stover mulching (CT), no-tillage without stover mulching (NTNS), and no-tillage with stover mulching (NTSM). The two low disturbance treatments promoted more soil bacterial species richness and diversity compared to CT. No-tillage alone homogenized the composition of the bacterial community through soil depth profiles, but straw mulching enhanced the uniqueness of community composition at each layer. Compared to CT, NT with residue increased soil water content and root associated organic carbon and decreased pH. More mineral N in the 0-150cm zone in NT systems than CT where N was lower in the profile. They conclude that low-disturbance practices can regenerate whole-soil bacterial diversity and potential function, and promote water retention and nitrogen holding capacity within the root zone.

This paper reports on the rice-maize system in Bangladesh, an expanding system in this country. Traditionally, this systems cultivates puddled transplanted rice followed by tilled maize. This is labor intensive, reduces soil health and is less profitable. As such, a field study looked at conservation agriculture (CA) based tillage and crop establishment (TCE) techniques and residue management practices on the physical, chemical, and biological properties of soil along with crop productivity and the profitability of rice-maize systems in the sandy loam soil of Northwest Bangladesh. The authors concluded that CA could be an appropriate practice for sustaining soil fertility and crop yield under R-M systems in light-textured soils or other similar soils in Bangladesh. 

This paper considers the short-term effects of wheat-maize and wheat-soybean on fractions of soil organic carbon, P and other soil quality properties in the 0-200mm and 200-400mm soil depths on CA farms. Water-soluble carbon and available phosphorus (P) (NaHCO3 Pi) were significantly higher and NaOH  Pi was lower in maize/wheat than in soybean/wheat sequences. SOC, extractable P, and NaHCO3 Pi were significantly higher in the 0–200 mm than in the 200–400 mm depth. They conclude that short-term cropping sequences do not affect SOC sequestration but a wheat crop preceded by maize could benefit from higher soil pH and labile C fractions making P more available, with the additional benefit of available K in these CA systems.

This study used 6 plots using CA installed in 1984 in Uruguay to quantify changes in soil quality contribute to current runoff and soil erosion in a cropping system under soil conservation practices - NT, residue retention and cover crops. Plots were grouped in three treatments with contrasting historic index of agricultural intensification (IAI). The IAI was developed combining the duration of land use under agricultural production and the number and intensity of tillage activity resulting in the treatments: tillage with crop-pasture rotation (TIL_CP), no-tillage under several rotations (NT_Mix) and tillage with continuous cropping (TIL_CROP) with an increasing IAI of 3.5, 7.1 and 11.8, respectively. Rainfall events, runoff water and total, fixed and volatile solids were studied from 2017 to 2019. Soil physical and chemical parameters were measured. The lowest soil losses were observed in TIL_CP. They conclude that CA minimized soil erosion losses in all plots and years, and erosion was much lower than the maximum tolerable threshold of 7,000 kg/ha for this particular soil.