Long-term Tillage Research Articles

Sustaining Soil Biological Activity: The Role of Extended Reduced and No-Tillage Techniques

Soil management techniques can have varying effects on various soil properties. This study investigated the impact of various tillage techniques on soil properties for 14 years. The experiment was conducted at the Çukurova University Research Station, located in a region with a dominant Mediterranean climate. The research aimed to assess the changes in soil organic matter (SOM) content, soil respiration (SR), dehydrogenase enzyme activity (DHA), and soil temperature (ST) under seven different long-term tillage practices. The results revealed significant increases (p ≤ 0.05) in SOM (17-115%), SR (19-37%), and DHA (63-142%), under conservation tillage compared to conventional tillage practices. Additionally, conventional tillage with stubble burned consistently had the lowest values across all measured properties. Seasons variations also significantly (p≤0.05) affected the observed values. These findings suggest that conventional tillage practices have a negative effect on the analyzed biological activities, with stubble burning further exacerbating this impact. Further research exploring the long-term effects of different tillage practices under varying crop rotations and soil conditions can contribute to the sustainable development of agricultural production in the region.

Long-term tillage and crop rotation effects on soil carbon and nitrogen stocks in southwestern Ontario

Conservation tillage and crop rotation diversification have been promoted to increase soil C and N storage; however, the interactive effects of tillage and crop rotation on soil C and N dynamics remain contradictory. Using a long-term (24-yr) experiment established at a clay loam site (Orthic Humic Gleysol) at Ridgetown, Ontario, Canada, the interactive effects of five crop rotations and two tillage systems were tested on soil organic C (SOC) and total N storage in soil depth increments and in the full soil profile (0-0.6 m) in 2019. While crop rotation influenced SOC and total N concentration in top 0.2 m, these effects were minimized when storage was expressed on an equivalent soil mass basis. Over the 0-0.6 m depth, no-tillage had 24 Mg SOC ha-1 and 4.7 Mg total N ha-1 greater content, respectively, than conventional tillage, supporting the value of no-tillage on increasing soil C and N in the long-term. Interestingly, no interactive effects of crop rotation and tillage on soil C and N storage in 0-0.6 m were observed. While the type of crop species and amount of C and N inputs under different crop rotations are important variables impacting the soil C and N storage, our results suggest that the crop rotation diversity was not a major driver of soil C and N in this study. Future mechanistic investigations exploring the persistence and linkage of soil C and N with crop rotation diversity in the tested production systems are needed.

Relationship of Microbial and Fertility Attributes to Organic Carbon Accumulation in a Subtropical Weathered Soil Impacted by a Long-Term Tillage Chronosequence

Relationship of Microbial and Fertility Attributes to Organic Carbon Accumulation in a Subtropical Weathered Soil Impacted by a Long-Term Tillage Chronosequence

Stratified Effects of Tillage and Crop Rotations on Soil Microbes in Carbon and Nitrogen Cycles at Different Soil Depths in Long-Term Corn, Soybean, and Wheat Cultivation.

Understanding the soil bacterial communities involved in carbon (C) and nitrogen (N) cycling can inform beneficial tillage and crop rotation practices for sustainability and crop production. This study evaluated soil bacterial diversity, compositional structure, and functions associated with C-N cycling at two soil depths (0-15 cm and 15-30 cm) under long-term tillage (conventional tillage [CT] and no-till [NT]) and crop rotation (monocultures of corn, soybean, and wheat and corn-soybean-wheat rotation) systems. The soil microbial communities were characterized by metabarcoding the 16S rRNA gene V4-V5 regions using Illumina MiSeq. The results showed that long-term NT reduced the soil bacterial diversity at 15-30 cm compared to CT, while no significant differences were found at 0-15 cm. The bacterial communities differed significantly at the two soil depths under NT but not under CT. Notably, over 70% of the tillage-responding KEGG orthologs (KOs) associated with C fixation (primarily in the reductive citric acid cycle) were more abundant under NT than under CT at both depths. The tillage practices significantly affected bacteria involved in biological nitrogen (N2) fixation at the 0-15 cm soil depth, as well as bacteria involved in denitrification at both soil depths. The crop type and rotation regimes had limited effects on bacterial diversity and structure but significantly affected specific C-N-cycling genes. For instance, three KOs associated with the Calvin-Benson cycle for C fixation and four KOs related to various N-cycling processes were more abundant in the soil of wheat than in that of corn or soybean. These findings indicate that the long-term tillage practices had a greater influence than crop rotation on the soil bacterial communities, particularly in the C- and N-cycling processes. Integrated management practices that consider the combined effects of tillage, crop rotation, and crop types on soil bacterial functional groups are essential for sustainable agriculture.

Impact of long-term tillage on the soil organic carbon storage and its composition in black soil.

Soil organic carbon (SOC) is essential for maintaining soil fertility and promoting sustainable agricultu-ral development. We investigated the impact of long-term tillage practices on soil organic carbon storage (SOCS) and its components in dryland farming areas of the black soil region, based on a 39-year tillage practice experiment. We compared the effects of different tillage practices (conventional rotary and ridge tillage, CT; no-tillage, NT; subsoiling tillage, ST; moldboard plowing, MP) on SOCS, active organic carbon components, and microbial necromass carbon (MNC) content in the 0-40 cm soil layer. The results showed that, compared to CT, NT significantly increased the contents of SOCS, SOC, dissolved organic carbon (DOC), microbial biomass carbon (MBC), easily oxidizable organic carbon (EOC), and MNC in the 0-20 cm soil layer. Both ST and MP significantly improved the contents of SOCS, SOC, and EOC in 0-20 and 20-40 cm soil layers compared to CT and increased MBC content in the 20-40 cm soil layer. Additionally, MP treatment significantly improved the contents of DOC, particulate organic carbon, and MNC in the 20-40 cm soil layer compared to other treatments. ST and MP significantly reduced the contribution rate of MNC to SOC in both soil layers compared to CT and NT treatments. Results of structural equation modeling showed that enhancing the mean weight diameter of soil aggregates, field capacity, and total phosphorus content, along with increasing the activities of β-glucosidase, amylase, and lignin peroxidase, could promote MNC accumulation. MP treatment facilitated the uniform distribution of SOC, active organic carbon, and MNC in the 0-40 cm soil layer, which was more conducive to the fixation of SOC in farmland in the black soil region.

Effect of long-term tillage practices on soil nitrogen, phosphorus and sulfur release under different nitrogen management options

The conservation agriculture (CA), presents a promising alternative for restoring soil health and achieving sustainable crop production. In addition, one cannot follow the same nitrogen management of conventional framing in the CA as the crop residue retained leads to N mineralization/immobilization. Hence, the present research was aimed to determine the effect of CA and nitrogen managements on soil nitrogen, phosphorus and sulfur release and the enzymes involved in their mineralization. The results revealed that the CA practice significantly enhanced the mineral N, Olsen P and CaCl2–S release and the soil enzymes involved in this mineralization cycles compared to CT + R plots. Similarly, all the nitrogen fertilizer receiving subplots also recorded significantly higher mineral N, Olsen P and CaCl2–S release and the enzymes involved compared to the control. Furthermore, throughout the incubation period the Urea super granule + Greenseeker treatment significantly outperformed the RDN plot with respect to NO3–N and CaCl2–S release. Whereas, the Urea + Greenseeker treatment registered significantly higher NO3–N and CaCl2–S over RDN plot from 30 and 45 days after incubation, respectively. The NH4–N and Olsen P release had increasing trend up to 45 days after incubation and thereafter it decreased. In nutshell, the research emphasizes the significance of CA alongside optimum nitrogen management approaches in enhancing the soil enzymatic activities and nutrient mineralization. These outcomes hold significance for both farmers and researchers seeking ecologically sound and productive agricultural methods to enhance crop output and maintain soil quality.

Dependency of Long-Term Soil Quality Controls on Summer Fallow Tillage and Soil Layers for Dryland Winter Wheat in Loess Plateau

The capacity for winter wheat to produce sufficient yield may be influenced by soil tillage practices and soil quality. However, determining how to quantify the impact of long-term tillage on soil quality is crucial. Here, we address this issue by comparing soil properties and wheat yield under four tillage systems during summer fallow in the Loess Plateau. Twenty-two soil properties were explored to estimate soil quality. Results showed that a rotational tillage (PT/ST) during summer fallow decreased soil bulk density (ρb) and improved soil gravimetric water content (θg), soil organic carbon (SOC), soil capillary porosity (Pc), and total porosity (Pt) in 0–50 cm soil layers. A minimum dataset (MDS) of thirteen indicators was selected to calculate soil quality index (SQI). Treatment of PT/ST had higher SQI value in soil layers of 0–10 cm and 20–50 cm, and PT/ST showed a significant increase in yield since the third year. No tillage (NT) during summer fallow decreased soil physical and chemical indicators, thus decreasing soil quality. These findings suggest that a rotation tillage of PT/ST during summer fallow could enhance soil chemical and biological properties concurrently, and PT/ST may provide a promising management strategy to sustain soil quality and grain yield for dryland winter wheat in the Loess Plateau.

Microbial Proxies for Anoxic Microsites Vary with Management and Partially Explain Soil Carbon Concentration.

Anoxic microsites are potentially important but unresolved contributors to soil organic carbon (C) storage. How anoxic microsites vary with soil management and the degree to which anoxic microsites contribute to soil C stabilization remain unknown. Sampling from four long-term agricultural experiments in the central United States, we examined how anoxic microsites varied with management (e.g., cultivation, tillage, and manure amendments) and whether anoxic microsites determine soil C concentration in surface (0-15 cm) soils. We used a novel approach to track anaerobe habitat space and, hence, anoxic microsites using DNA copies of anaerobic functional genes over a confined volume of soil. No-till practices inconsistently increased anoxic microsite extent compared to conventionally tilled soils, and within one site organic matter amendments increased anaerobe abundance in no-till soils. Across all long-term tillage trials, uncultivated soils had ∼2-4 times more copies of anaerobic functional genes than their cropland counterparts. Finally, anaerobe abundance was positively correlated to soil C concentration. Even when accounting for other soil C protection mechanisms, anaerobe abundance, our proxy for anoxic microsites, explained 41% of the variance and 5% of the unique variance in soil C concentration in cropland soils, making anoxic microsites the strongest management-responsive predictor of soil C concentration. Our results suggest that careful management of anoxic microsites may be a promising strategy to increase soil C storage within agricultural soils.

Mineral and organic fertilisation influence ammonia oxidisers and denitrifiers and nitrous oxide emissions in a long-term tillage experiment

Nitrous oxide (N2O) emissions from different agricultural systems have been studied extensively to understand the mechanisms underlying their formation. While a number of long-term field experiments have focused on individual agricultural practices in relation to N2O emissions, studies on the combined effects of multiple practices are lacking. This study evaluated the effect of different tillage [no-till (NT) vs. conventional plough tillage (CT)] in combination with fertilisation [mineral (MIN), compost (ORG), and unfertilised control (CON)] on seasonal N2O emissions and the underlying N-cycling microbial community in one maize growing season. Rainfall events after fertilisation, which resulted in increased soil water content, were the main triggers of the observed N2O emission peaks. The highest cumulative emissions were measured in MIN fertilisation, followed by ORG and CON fertilisation. In the period after the first fertilisation CT resulted in higher cumulative emissions than NT, while no significant effect of tillage was observed cumulatively across the entire season. A higher genetic potential for N2O emissions was observed under NT than CT, as indicated by an increased (nirK + nirS)/(nosZI + nosZII) ratio. The mentioned ratio under NT decreased in the order CON > MIN > ORG, indicating a higher N2O consumption potential in the NT-ORG treatment, which was confirmed in terms of cumulative emissions. The AOB/16S ratio was strongly affected by fertilisation and was higher in the MIN than in the ORG and CON treatments, regardless of the tillage system. Multiple regression has revealed that this ratio is one of the most important variables explaining cumulative N2O emissions, possibly reflecting the role of bacterial ammonia oxidisers in minerally fertilised soil. Although the AOB/16S ratio aligned well with the measured N2O emissions in our experimental field, the higher genetic potential for denitrification expressed by the (nirK + nirS)/(nosZI + nosZII) ratio in NT than CT was not realized in the form of increased emissions. Our results suggest that organic fertilisation in combination with NT shows a promising combination for mitigating N2O emissions; however, addressing the yield gap is necessary before incorporating it in recommendations for farmers.

Computed tomography scanning revealed macropore-controlled N2O emissions under long-term tillage and cover cropping practices

Microscale alterations in soil physical characteristics resulting from long-term soil health practices can contribute to changes in soil nitrous oxide (N2O) emissions. In this study, we investigated soil N2O emissions in relation to pore characteristics influencing soil gas diffusivity under long-term tillage and cover cropping practices. Intact soil cores from tillage (conventional tillage, Conv. T versus no tillage, NT) and cover crop (hairy vetch, HV versus no cover crop, NC) treatments were used for N2O measurements and computed tomography (CT) scanning. Using X-ray CT technique with a resolution of 59 μm, pore structure parameters including macroporosity, number of macropores, anisotropy, fractal dimension, tortuosity, and connectivity were determined. The results showed that Conv. T and HV emitted significantly higher N2O than NT and NC, respectively. A similar trend was observed for macroporosity, Conv. T soils had 27.4 % higher CT-derived macroporosity than the NT soils and HV increased macroporosity by 31.1 % over the NC treatment. The number of macropores and fractal dimension were significantly higher whereas degree of anisotropy was significantly lower under HV compared to NC. In the upper 3 cm of soil, HV had a connected porosity, whereas the pores were disconnected and isolated in NC. These CT-derived properties; however, were not impacted by tillage treatments. N2O emissions were positively and significantly correlated to relative soil gas diffusivity, CT-derived macroporosity, number of macropores, and fractal dimension. Our results demonstrated that soil macroporosity and relative gas diffusivity could lead to improved understanding and predictability of N2O emissions under high soil moisture conditions.

Effects of transitioning from conventional to organic farming on soil organic carbon and microbial community: a comparison of long-term non-inversion minimum tillage and conventional tillage

The combination of conservation tillage (non-inversion and no-till) with organic farming is rare due to weed problems. However, both practices have the potential to improve soil quality and increase soil organic C (SOC). This study investigated the changes in SOC, microbial biomass, and microbial composition during the transition from conventional to organic farming (from 2014 to 2020) in a long-term tillage trial established in 1999. Non-inversion minimum tillage to a depth of 10 cm (MT) resulted in SOC stratification, whilst conventional soil tillage with 25-cm-deep mouldboard ploughing (CT) maintained an even SOC distribution in the plough layer. After 12 years of contrasting tillage in 2011, the uppermost soil layer under MT had a 10% higher SOC content (1.6% w/w) than CT (1.45% w/w). This difference became even more pronounced after introducing organic farming in 2014. By the fall of 2020, the SOC content under MT increased to 1.94%, whilst it decreased slightly to 1.36% under CT, resulting in a 43% difference between the two systems. Conversion to organic farming increased microbial biomass under both tillage systems, whilst SOC remained unchanged in CT. Abundances of total bacterial and Crenarchaeal 16S rRNA and fungal ITS genes indicated shifts in the microbial community in response to tillage and depth. Fungal communities under MT were more responsive to organic farming than bacterial communities. The improved soil quality observed under MT supports its adoption in both organic and conventional systems, but potentially large yield losses due to increased weed cover discourage farmers from combining MT and organic farming.

X-ray computed tomography – Measured pore characteristics and hydro-physical properties of soil profile as influenced by long-term tillage and rotation systems

Soil hydro-physical properties and pore characteristics are crucial for crop production as they determine water, air, and nutrients transfer. Long-term tillage and crop rotation studies provide valuable insights into the effects of management practices on various soil properties. Because of the inherent differences between the surface and sub-surface soils, the impact of management systems can be pronounced differently at different soil depths. Though many studies have reported the tillage and rotation effects on soil hydro-physical properties, their vertical impacts to a depth of 40 cm were less explored. This study aims to assess the impact of long-term tillage and crop rotations on soil hydro-physical properties and pore characteristics to a depth of 40 cm utilizing the X-ray Computed Tomography (XCT) technique. Intact soil cores of 7.6 cm height × 7.6 cm ∅ were collected from tillage [no-till (NT); reduced-till (RT); conventional-till (CT)] and crop rotation [continuous corn (CC) – Zea mays L. and corn-soybean (CS) – Glycine max [Merr.] L.] plots of 0–40 cm depth (each sample for 10 cm increment). The XCT scanning allowed us to investigate the soil pore size distribution, porosity, number of branches, and average branch length. Measured hydro-physical properties in the study include bulk density (ρb), plant available water content (PAW), saturated hydraulic conductivity (Ksat), and water retention. XCT image analysis revealed that NT with CC/CS rotation increased the number of macropores at surface and sub-surface depths. However, the number of mesopores was higher with NT × CS. In addition, NT lowered the ρb by 9.6 % and increased the PAW by 28 % compared to the CT. Ksat was higher under NT × CS at 0–10 cm and had a strong positive correlation with the XCT-measured number of macropores. Therefore, we conclude that NT with CS rotation can potentially improve soil pore characteristics and hydro-physical properties, leading to enhanced soil function.

Long-term conservation tillage enhances microbial carbon use efficiency by altering multitrophic interactions in soil

Microbial carbon (C) use efficiency (CUE) plays a key role in soil C storage. The predation of protists on bacteria and fungi has potential impacts on the global C cycle. However, under conservation tillage conditions, the effects of multitrophic interactions on soil microbial CUE are still unclear. Here, we investigate the multitrophic network (especially the keystone ecological cluster) and its regulation of soil microbial CUE and soil organic C (SOC) under different long-term (15-year) tillage practices. We found that conservation tillage (CT) significantly enhanced microbial CUE, turnover, and SOC (P < 0.05) compared to traditional tillage (control, CK). At the same time, tillage practice and soil depth had significant effects on the structure of fungal and protistan communities. Furthermore, the soil biodiversity of the keystone cluster was positively correlated with the microbial physiological traits (CUE, microbial growth rate (MGR), microbial respiration rate (Rs), microbial turnover) and SOC (P < 0.05). Protistan richness played the strongest role in directly shaping the keystone cluster. Compared with CK, CT generally enhanced the correlation between microbial communities and microbial physiological characteristics and SOC. Overall, our results illustrate that the top-down control (the organisms at higher trophic levels affect the organisms at lower trophic levels) of protists in the soil micro-food web plays an important role in improving microbial CUE under conservation tillage. Our findings provide a theoretical basis for promoting the application of protists in targeted microbial engineering and contribute to the promotion of conservation agriculture and the improvement of soil C sequestration potential.

Soil Health Assessment in Brazilian Subtropical Oxisol Under Land Use and Long-term Tillage Systems

Soil Health Assessment in Brazilian Subtropical Oxisol Under Land Use and Long-term Tillage Systems

Mycorrhizal effects on crop yield and soil ecosystem functions in a long-term tillage and fertilization experiment.

It is well understood that agricultural management influences arbuscular mycorrhizal (AM) fungi, but there is controversy about whether farmers should manage for AM symbiosis. We assessed AM fungal communities colonizing wheat roots for three consecutive years in a long-term (> 14 yr) tillage and fertilization experiment. Relationships among mycorrhizas, crop performance, and soil ecosystem functions were quantified. Tillage, fertilizers and continuous monoculture all reduced AM fungal richness and shifted community composition toward dominance of a few ruderal taxa. Rhizophagus and Dominikia were depressed by tillage and/or fertilization, and their abundances as well as AM fungal richness correlated positively with soil aggregate stability and nutrient cycling functions across all or no-tilled samples. In the field, wheat yield was unrelated to AM fungal abundance and correlated negatively with AM fungal richness. In a complementary glasshouse study, wheat biomass was enhanced by soil inoculum from unfertilized, no-till plots while neutral to depressed growth was observed in wheat inoculated with soils from fertilized and conventionally tilled plots. This study demonstrates contrasting impacts of low-input and conventional agricultural practices on AM symbiosis and highlights the importance of considering both crop yield and soil ecosystem functions when managing mycorrhizas for more sustainable agroecosystems.

Addition of biochar decreased soil respiration in a permanent no-till cover crop system for organic soybean production

The increase in soil carbon sequestration under long-term no-till (NT) and cover crop management has been shown to form part of a sustainable agricultural management practice system. Along with the increase in soil organic carbon (SOC), soil respiration in this system was also enhanced by the increased soil temperature through the decomposition that causes carbon loss from the soil. To overcome this issue, biochar can be applied. However, the addition of biochar into this system is not well studied. Therefore, the aim of this study was to investigate the effect of this system on soil respiration. The experiment was conducted at the Center for International Field Agriculture Research & Education, Ibaraki University. Long-term tillage practices, such as NT and moldboard plowing (MP), cover crops such as rye (RY) and fallow (FA), and biochar application such as with biochar (WB) and no biochar (NB) were applied to a split–split plot in a randomized complete block design with four replications. The daily CO2 flux was measured every week at 9:00–11:00 a.m. The daily soil respiration was affected by tillage and cover crop with NT practice had significantly higher daily CO2 flux than that of MP (23.8%–107.4% and 38.0%–107.8%), while RY had higher flux than that of FA (11.9%–81.2% and 34.9%–65.4%) in 2020 and 2021 soybean growing season, respectively. Additionally, in the 2020 cover crop growing season RY also increased daily CO2 flux approximately 41.8%–88.2% compared to FA. Biochar addition significantly reduced soil respiration in soybean and cover crop seasons compared to NB by 24.0%–50.7% and by 25.9%–48.3%, respectively. This reduction in soil respiration by the biochar decreased annual CO2 emissions by 17.6% and 13.0% in 2020 and 2021. The values of these emissions ranged from 9.6 Mg ha−1 for MP FA WB to 18.9 Mg ha−1 for MP RY NB in 2020 and from 7.5 Mg ha−1 for MP FA WB to 13.7 Mg ha−1 for NT FA NB in 2021. This study highlights the crucial role of biochar in reducing soil respiration and enhancing SOC sequestration. The addition of biochar into this system was able to reduce soil respiration by regulating the soil temperature, soil moisture, and protect the SOC from decomposition. Biochar addition also increased the SOC and decreased the soil bulk density, which improves soil porosity. Therefore, these findings would be very useful to be included within the global scenario of soil organic matter management.

Long-term Tillage Practices Impact Soil Aggregation and Climate Resilience in Tunisian Field Cropping Systems

Soil degradation poses a major challenge for agricultural and socio-economic development in Tunisia. The conventional intensive cultivation practices commonly used by farmers cause rapid depletion of soil organic matter, which is adversely affecting the physio-chemical properties of soil and is accelerating soil erosion. The decrease in soil organic carbon stocks is a major factor aggravating the impacts of climate change.

Tillage effects on growing season nitrous oxide emissions in Canadian cropland soils

Minimizing tillage has been promoted as an agricultural practice that may mitigate greenhouse gas emissions through carbon sequestration. However, there is some ambiguity regarding the effect of minimum tillage (MT) on emissions of other greenhouse gases, in particular soil nitrous oxide (N2O) emissions. To determine how effective MT could be in helping Canada mitigate greenhouse gas emissions, we used a meta-analysis to compare growing season N2O emissions from MT versus conventional tillage (CT). Overall, MT had 12% lower N2O emissions compared to CT ( P = 0.03). However, there was high variability due to soil texture and growing season precipitation (GSP), with MT tending to emit more N2O than CT in climates where GSP exceeded 600 mm, particularly for soils with sand content less than 60%. Therefore, unless long-term tillage trials, which are urgently needed in eastern Canada, show a reduction in N2O emissions over time, MT should be used as a greenhouse gas mitigation measure only in dry climates or on sandy soils.

Impact of tillage systems on maize emergence

In Europe, there has been a significant change in the way tillage is approached in recent years. This change is due to a growing awareness among farmers, politicians and society as a whole that soil is not a renewable resource in itself. From an agricultural point of view, the greatest impact on soil condition can be achieved through the use of the applied tillage systems. My research takes this approach as a basis when examining the different tillage systems and their impact on the environment. In this context, conventional and a variety of no-tillage systems are examined in this paper. As a next step, it is examined how the environmental conditions created by the different tillage systems influence the emergence of maize hybrids. The analyses are carried out in a multi-factorial, long-term tillage field experiment. The same batch of the same hybrid seed was sown in several crop years, and the effects of environmental conditions on the emergence process were examined. Environmental effects and emergence-related uptake were measured in the examined plots. Measurements of environmental effects included air temperature, precipitation, soil temperature measured at seeding depth, as well as % cover of stem residue on the surface in the treated plots. The first emergence time measurements of the sown crop in the plots of each treatment were compared and relationships between these factors were investigated.

Long-term conservation tillage improves soil stoichiometry balance and crop productivity based on a 17-year experiment in a semi-arid area of northern China

Although conservation tillage has been widely implemented to address the challenge to improve crop yield and soil quality with fewer environmental costs, its long-term effects on crop yields and soil stoichiometry balance remain uncertain. Here, four different long-term (17-year) tillage practices (conventional tillage (CT), deep scarification (DS), no tillage (NT), and ridge tillage (RT)) were conducted in northern China to evaluate their effects on crop yield, soil nutrients, C sequestration, and soil stoichiometry. The conservation tillage (DS, NT, and RT) increased the recent 5-year average yields by 12.2 %–20.1 % compared with CT, respectively. RT showed the highest C sequestration potential of 10.0 t/ha, followed by DS and NT (6.0 t/ha and 4.4 t/ha, respectively). The DS, NT, and RT enhanced soil available N and K with the best effect for NT, but DS reduced soil total and available P. The conservation tillage significantly increased the C:N, C:P, C:K, and N:P ratios, indicating it sustained soil balanced stoichiometry. Correlation analysis indicated crop yield was closely related to soil C:N, C:P, C:K, and N:P. The structural equation model revealed that the C, N, and P affected C:N and C:P ratios, thus improving crop yield under long-term conservation tillage. In summary, long-term conservation tillage improves soil stoichiometry balance and thus crop yields with great C sequestration potential to achieve sustainable agricultural management in rain-fed farmland.