Brassicaceae cover crops are widely adopted in agroecosystems, yet their legacy effects on arbuscular mycorrhizal fungi (AMF) remain context-dependent and mechanistically unresolved. In this study, we assessed how a standing white mustard (Sinapis alba L.) cover crop interacts with tillage intensity to influence AMF colonization, community composition, diversity, and abundance in volunteer barley (Hordeum vulgare L.) roots. AMF responses were quantified using complementary approaches, including microscopic assessment of root colonization, 18S rRNA gene amplicon sequencing, and taxon-specific real-time PCR (qPCR). Roots were sampled before white mustard termination, thereby avoiding tissue disruption and isothiocyanate release, to distinguish host-mediated filtering from biofumigation-associated chemical disturbance. Colonization intensity was primarily determined by tillage, with significantly higher colonization under no-tillage compared to conventional tillage. Community-level responses, however, were dependent on taxonomic resolution. At the amplicon sequence variant (ASV) level, white mustard reduced AMF richness, whereas diversity and evenness were unaffected. At the genus level, richness remained stable, but diversity and evenness declined under the combined effects of cover cropping and conventional tillage, indicating that tillage modulated the impact of cover crop legacy. Dominant Glomeraceae lineages remained stable across treatments, and total AMF abundance showed no consistent response to management, although Rhizophagus irregularis was more abundant under no-tillage. Colonization intensity correlated with ASV richness rather than with individual taxa, suggesting that early symbiotic dynamics were linked to community diversity rather than to the dominance of specific lineages. These findings suggest that white mustard cover cropping, despite its well‑recognized agronomic benefits, may also carry context‑dependent shifts in AMF communities, highlighting a potential ecological trade‑off that should be considered when designing cover crop-tillage management combinations.

Spatial assessment of no-tillage effects on cropland wind erosion dust and regional air quality: A coupled WEPS-WRF/Chem study in Kaifeng, China.

Excessive fertilizer use threatens soil quality and the sustainability of grain production, making improvements in fertilizer use efficiency (FUE) essential. This study examines how conservation tillage (CT) practices affect FUE in China’s wheat–maize rotation system using survey data from 1528 farm households in Shandong, Henan, Anhui, Shaanxi, and Shanxi provinces of China. We estimate FUE using stochastic frontier analysis (SFA) and identify the treatment effects of tillage choices using a multinomial endogenous switching regression (MESR) model to correct for self-selection. Three tillage practices are compared: conventional rotary tillage with straw returning (CTS), no-tillage with straw returning (NTS), and deep tillage with straw returning (DTS). The results show that the average FUE of farmers in grain production in the sample area is 0.5045 and displays a bimodal distribution. Relative to CTS, NTS significantly improves farmers’ FUE, whereas DTS significantly reduces it. Mechanism analysis indicates that NTS improves FUE through both reduced fertilizer input and increased yield, while DTS mainly increases yield without reducing fertilizer input. Threshold analysis further shows that farm size conditions these effects. The findings suggest that CT policies should promote NTS more actively and apply DTS selectively according to farm size and local production conditions.

To explore the response of the black soil organic carbon pool to long-term tillage and its evolution characteristics， a field experiment initiated in 1983 was used to study the effects of conventional tillage （CT）， no-tillage （NT）， subsoiling tillage （ST）， and moldboard plowing tillage （MP） on the active organic carbon components and carbon pool in the 0-40 cm soil layer in 2013 and 2022. The results indicated that compared to those under the CT treatment， the NT， ST， and MP treatments significantly increased the organic carbon （SOC）， readily oxidizable organic carbon （ROC） content， and carbon pool management index （CPMI） in the 0-40 cm soil layer in 2013 and 2022， with average increases of 11.92% to 31.89%， 25.64% to 48.72%， and 30.57% to 80.32%， respectively， with the MP treatment showing the highest increase. ST significantly increased the particulate organic carbon （POC） content compared to that in other treatments， with an increase of 13.20% to 52.15%. Compared to those in 2013， all treatments significantly reduced the POC， ROC content， and CPMI in the 0-40 cm soil layer in 2022， with the NT and ST treatments showing the largest and smallest decreases， respectively. The CT and NT treatments also significantly reduced SOC content， while the ST treatment increased SOC content by 10.71%. Redundancy analysis and structural equation modeling indicated that the activities of soil amylase， β-glucosidase， cellulase， and lignin peroxidase were the main factors affecting the changes in POC， ROC content， and CPMI. In summary， long-term MP resulted in the highest SOC content in the 0-40 cm soil layer， with enhanced stability， maintaining the highest carbon pool management index， which is more beneficial for SOC sequestration in black soil farmland. Under the drive of long-term tillage， the black soil organic carbon pool showed a degradation evolution characteristic， with the NT showing the greatest degradation， while ST and MP had better degradation control effects.

ABSTRACT Conservation agriculture (CA)-based practices reduce the risk of soil nutrient depletion by promoting the stabilization and sequestration of organic carbon (C) and enhancing soil biological functioning. To address this, a field study was conducted to quantify the impact of rice establishment methods, tillage and residue management practices for eight-years to identify the critical growth stages of rice and wheat for assessing the biological properties of soil under rice-wheat cropping system (RWS). The results revealed that direct seeded rice-reduced tillage followed by zero tillage (ZT) with residue retention significantly improved soil's extracellular enzyme activities except phenol oxidase (PHEOX) and peroxidase (PERO) across five growth stages of rice-wheat systems. Dehydrogenase (DHA), fluorescein diacetate (FDA), alkaline phosphatase (Alk-P), β-glucosidase (β-glu), total polysaccharides carbon (TPC) and cellulase (CELL) activities were highest at the maximum tillering stage of rice and wheat than at other growth stages. At the maximum tillering stage of wheat, activities of DHA, FDA, Alk-P, β-glu and TPC under ZT-wheat with residue retention were 60.5, 35.8, 50.6, 30.4, and 31.1% higher than conventional tillage (CT) without residue. Furthermore, ZT-wheat with residue retention significantly increased wheat grain yield by 10.6% as compared to CT without residue. Principal component analysis (PCA) suggested that xylanase, phenol oxidase and FDA can be used as sensitive parameters for assessing soil quality under rice establishment methods, tillage and residue management practices in RWS. These findings highlight that practices like ZT with residue retention support sustainable intensification of RWS by enhancing soil biological fertility and crop productivity.

Beneath-the-surface nitrogen placement sustains maize productivity and soil health under long-term conservation agriculture in the NW Indo-Gangetic Plains

While no-till (NT), one of the pillars of conservation agriculture, is widely practiced in upland crops, considerably less research has been conducted in rice systems. While adoption has been limited, numerous field experiments have evaluated NT rice across diverse regions and management contexts yet reported yield responses to key agronomic practices, soil properties, and climatic conditions remain inconsistent and poorly synthesized at a global scale. Our objective was to conduct a global meta-analysis comparing the effects of NT to conventional tillage (CT) on rice yields and to identify the agronomic practices, soil characteristics, and climate factors most strongly associated with yield changes under NT. We performed a global meta-analysis of 115 studies (579 paired observations) comparing rice yields under NT and CT. Yield response ratios (lnRR) were analyzed using mixed-effects meta-analysis to estimate overall effects. Meta-regression and Random Forest modeling were used to assess relative importance of soil properties, management practices, and climatic factors influencing NT performance. Overall, there was a 4.8% yield reduction under NT. The key factors influencing yield were soil organic carbon (SOC), nitrogen (N) application rate, soil pH, and soil clay content. Soil SOC levels above 18 g ha⁻¹ , N rates above 120 kg ha⁻¹ , a pH range of 6 – 7, and clay content between 180 – 350 g kg⁻¹ were associated with improved NT yields. Residue retention and crop rotation – the other two key components of conservation agriculture along with minimum tillage – had limited influence on yield outcomes in flooded rice systems. This global meta-analysis provides the most up-to-date, and largest, global, quantitative framework for targeting NT. Results indicate that based on soil properties (higher SOC and clay content, moderate pH) coupled with sufficient N inputs, NT yields are highest. However, our analysis suggests that even under these more optimal conditions, NT yields might be similar to but not exceed CT yields. That said, given other benefits of NT, it may be economical under certain conditions. We conducted the most comprehensive and up-to-date global meta-analysis on NT impacts in rice since 2013. This study evaluates how soil properties, agronomic management, and climatic conditions influence yield differences between NT and conventional tillage (CT) and identifies the key conditions under which NT may be agronomically viable. • Global analysis of 579 paired observations (NT vs. CT) from 115 studies (1985 – 2025). • No-till caused a 4.8% decrease in yields compared to conventional tillage. • No-till yields improved in soils with fine texture, high carbon, and neutral soil pH. • No-till systems improved at higher N rates but were still below CT yields. • Rice establishment system, rotation, residues, and climate zone showed no effects.

While legume-based rotation influences the chemical composition of mineral-associated organic matter, tillage has little effect on its persistence

Weed management is a key to the adoption of conservation agriculture practices in Sub-Saharan Africa. This study assessed the effect of conservation agriculture practices, strip-tillage and direct mulch-based cropping system on weed emergence, biomass and community structure in cotton-based cropping systems in northern Benin. The experiment was conducted in 2023 and 2024 using a randomized complete block design with three replications under three cropping systems: conventional tillage, strip tillage (cotton in biannual rotation with maize-cowpea intercropping over strip tillage) and direct mulch-based cropping system (cotton in three-season rotation with maize and Stylosanthes guianensis intercropping and sorghum and soybean intercropping over direct mulch-based cropping system). Weed emergence and species were inventoried at seven-day intervals starting from the first rainfall triggering their germination. Weed biomass was measured at each weeding. Conservation agriculture systems significantly reduced weed emergence compared to conventional tillage. The reductions were 15 % (cotton) and 46 % (maize) under strip tillage, and 33 % (cotton) and 56 % (maize) under direct mulch-based cropping system. Weed biomass increased significantly under the strip tillage system, i.e. by 40 % in cotton plots and by 41 % in maize plots. Crop yields were not significantly affected by systems. Weed community structure was shaped by the interaction between the cropping system and seasons, with distinct indicator species associated with cropping systems. These findings demonstrate that conservation agriculture practices can reduce weed emergence and alter weed community structure without compromising yield performance. This is the first study to characterize weed management under conservation agriculture in Sub-Saharan African cotton-based cropping systems. • Conservation agriculture reduced weed emergence and biomass in a cotton-based system. • Strip-tillage reduced weed emergence but increased biomass compared to conventional tillage. • Tillage, intercropping and mulching influenced weed community structure. • No-/strip tillage led to greater dicots weed emergence in a cotton-based system. • There is no significant difference of cotton and maize yields between three systems.

Sustainable agriculture requires maintaining soil health, yet conventional management (CM) practices may not protect soils from stresses such as compaction. This study compared microbial resilience to compaction in two soils collected from sugarcane farms under improved management (IM: minimum tillage, cover cropping and stubble retention) and CM (conventional tillage, no cover crop and stubble retention) practices. Samples were placed in 96-well deep-well plates and compacted using a bespoke device to achieve bulk densities of 0.9 (control), 1.1 (low), and 1.2 g cm⁻³ (moderate). Microbial resistance was assessed 14 days after compaction, and resilience 14 days after stress relief. Under low and moderate compaction, IM soils showed 49.5 % and 45.7 % higher CO₂ emission resistance indices (i.e., the ability of soil to maintain microbial respiration under compaction stress) than CM, indicating greater stability. Microbial biomass carbon and nitrogen were 56.2 % and 47.9 % higher in IM soils under low compaction, compared to CM. Soil microbial metabolic quotient ( q CO₂) was similar across compaction levels within each system, but was 19.5 %–36.3 % lower in IM soils than CM at equivalent compaction, indicating lower microbial stress under IM. Fourteen days after stress relief, q CO₂ in moderately compacted CM soil increased by 41.1 % and 25.0 % compared to control and low compaction. In contrast, IM soil under moderate compaction had 40.6 % lower q CO₂ than CM. The CM showed no effects of compaction on hot water extractable organic carbon content, while compaction of IM showed a 13 % decline compared to its control. Hot water extractable total nitrogen did not vary with compaction within the management systems but was 12 %–15 % higher in IM than CM under the same compaction during the resistance phase. Total mineral nitrogen was unaffected by compaction treatments under each system but was 11 %–13 % higher in IM than CM during resistance phase. These findings highlight the potential of improved management practices to sustain soil health and resilience under compaction stress. • A novel test used to assess microbial functional resilience to compaction stress. • Improved management had higher respiration resistance than conventional management. • Improved management reduced microbial metabolic quotient under compaction stress. • Improved management enhanced microbial functional stability and nutrient retention.

ABSTRACT Intensive agricultural practices have accelerated soil degradation and greenhouse gas emissions, threatening global food security and climate stability. This study evaluated the interactive effects of tillage systems (reduced tillage (RT) vs. conventional tillage (CT)) and fertilizers (chemical fertilizer (+C), organic fertilizer (+O), and organic mulch (+M)) on soil organic carbon (SOC), soil water content (SWC), and carbon dioxide emissions (CO2) emissions in a factorial field experiment. Weekly monitoring was conducted over the 2024 growing season using a randomized complete block design with corn-soybean intercrops in sandy andosols under temperate climate at Niigata University, Japan. Statistical analyses employed Aligned Rank Transform Analysis of Variance (ART ANOVA) to analyze the 2 × 3 factorial design with non-normal data distributions. Results demonstrated that fertilizer system influenced SOC (η2 = 0.69) and SWC (η2 = 0.91), whereas tillage-fertilizer interactions affected CO2 emissions (η2 = 0.43). RT combined with organic mulch (RT+M) and CT combined with organic fertilizer (CT+O) improved SOC. However, CT+O simultaneously increased CO2 flux. These findings show the critical importance of fertilizer selection and demonstrate that integrating RT with organic mulch provides optimal benefits for SOC and SWC, and mitigates CO2 emissions in temperate cropping systems.

The Hexi Oasis irrigation area is endowed with abundant light and heat resources, making it suitable for intercropped maize systems. However, increasing water scarcity and the need for irrigation reduction have made the conventional full-irrigation, high-yield pathway difficult to sustain. Under reduced irrigation, yield penalties may occur because water limitation directly constrains stomatal opening and carbon assimilation during the critical silking-grain filling period. Whether intercropped maize can stabilize yield under limited water supply through coordinated maintenance of photosynthetic performance and regulation of key C4 enzymes remains unclear. To address this gap, a field experiment was conducted in 2022-2024 to systematically evaluate the coupled effects of tillage (no-tillage, NT; conventional tillage, CT), cropping pattern (intercropping, IM; monocropping, SM), and three irrigation regimes (low, I1; medium, I2; high, I3) on maize grain yield, photosynthetic physiology, and key enzyme regulation. The results showed that compared with the NT×IM×I2 group, the grain yields of the CT×IM×I2 and NT×SM×I2 groups increased significantly by 10.5% and 27.2% respectively. During the silking-grain filling stage, this treatment maintained the highest relative chlorophyll content, net photosynthetic rate, stomatal conductance and effective quantum yield of PSII photochemistry, along with the lowest intercellular CO2 concentration and quantum yield of non-regulated energy dissipation. Enzyme activities of phosphoenolpyruvate carboxylase, ribulose-1,5-bisphosphate carboxylase/oxygenase, and pyruvate phosphate dikinase increased by 6-11%, 8-10%, and 9-14%, respectively, with corresponding gene expression upregulated by 30-80%. In summary, NT combined with moderate irrigation enhanced intercropped maize yield stability under limited water supply through a dual mechanism of "photosynthetic performance maintenance + C4 enzyme activity/transcription enhancement."

Soil health is a priority in European policies, such as the EU Soil and Biodiversity Strategies for 2030, owing to land degradation and climate change, with Mediterranean vineyards being especially vulnerable because of their low soil organic matter content and risk of erosion. To improve sustainability, cover crops are increasingly used as alternatives to conventional tillage with bare soils. This study assessed the effects of different ground cover strategies on soil health, grape production, and biodiversity in Vitis vinifera cv. Tempranillo vineyard (D. O. Ribera del Duero, Spain). Four soil management systems were compared in 2021–2022: conventional tillage (CT), natural green cover (NGC), a sown grass–legume mixture (SGC), and a sown grass–flower mixture (FGC), in a randomized block design with four replicates. Surface soils (0 cm–20 cm) were sampled in spring 2022 and analyzed for pH, EC, organic matter, total nitrogen, soluble nutrients, microbial biomass, and enzymatic activity, as well as SPAD measurements to monitor plant development, yield, and grape quality. The yield decreased by 75% under FGC compared to that under CT. Soil Organic Carbon (SOC) increased by 57% in SGC compared to CT. Cover crops reduced grape yield but improved quality, notably by increasing anthocyanin content in the must. They also improved the biodiversity of the vineyards and increased the organic carbon content of the soil compared to CT. However, they depleted available nutrients, particularly nitrates, and showed only limited effects on soil biological properties, such as enzyme activities. Overall, cover crops promoted ecosystem services but required trade-offs with yield and soil nutrient availability.

Abstract. Smallholder agriculture in sub-Saharan Africa (SSA) commonly involves limited use of mineral or organic fertilizer, often resulting in severe nutrient limitation. Conservation Agriculture (CA), including crop rotation with legumes and biochar amendments, has been advocated to enhance soil fertility and plant available nitrogen (N). However, CA may affect nitrous oxide (N2O) emissions even in unfertilized agroecosystems. N2O is an important greenhouse (GHG) gas, and understanding the trade-offs between N2O emissions and crop yields in N-poor agroecosystems in SSA is essential. Here we studied crop yield, soil N dynamics and N2O emissions in a double cropping system (pigeon pea–maize rotation) throughout two consecutive cropping seasons (April–October 2023 and October 2023–January 2024) in a Ferralsol in Northern Uganda. The study, conducted at a site which had been left fallow for 3 years, involved pairwise comparison of conventionally tilled systems under crop rotation (Conventional) and continuous maize monocropping (ConventMM). In addition, the effect of tillage systems (Conventional, CA and CA + biochar) under pigeon pea–maize rotation was investigated. We defined CA as reduced tillage with planting basins, crop rotation and residue retention, whereas conventional tillage involved overall ploughing. N2O fluxes were small, ranging from 1.02–51.19 µg N m2 h−1 over the entire period. Short-lived emission peaks were observed following pigeon pea harvest in the crop rotation, which were absent in maize monocropping. Across two growing seasons, area-weighted cumulative N2O emissions for 279 d ranged from 0.46 kg kg N ha−1 in CA + BC treatment to 0.88 kg N ha−1 in the Conventional treatment, respectively. CA + BC reduced area-weighted N2O emissions by 33 % and 66 % compared to Conventional treatment in the first and second season, respectively. In addition, biochar amendments in CA systems also reduced yield-scaled N2O emissions by 48 % across two seasons. In the first season, yield-scaled N2O emissions and N yield scaled N2O emissions were significantly smaller in CA systems with biochar compared to conventional tillage, suggesting that CA and biochar was effective in minimising emissions without reducing pigeon pea yield, in the first year after field clearing.

Cotton productivity in the Indo-Gangetic loamy sands has remained stagnant, largely due to subsoil compaction, which restricts water infiltration and root elongation. This study quantified the effects of one-time sub-soiling, applied as single or cross passes at different spacings, on soil hydraulics, root and fruit development and seed cotton yield (SCY) using analytical approaches beyond conventional mean comparisons. Five tillage treatments, including conventional tillage (CT) and 4 subsoiling configurations, were evaluated across 3 site-years on fixed plots in Punjab, India. Treatment responses were assessed using effect size estimates (Hedges g) for key traits, while a piecewise structural equation model traced the causal pathways linking tillage intensity (TI) to infiltration rate (IR), root length (RL), fruiting capacity and yield. A quadratic response surface regression was used to identify the joint optimum of the IR and RL. Cross sub-soiling at 1 × 1 m spacing increased infiltration by 10–13 mm h-1, enhanced rooting depth by 31–33 % and improved SCY by approximately 33 % relative to CT. Structural equation modelling indicated that 57 % of the total tillage effect on yield was mediated through improved soil hydraulics, with an additional 34 % being mediated through enhanced fruiting capacity. The response surface explained 80 % of the yield variability and identified an optimum near a 40 mm h-1 IR and 110 cm RL, with small deviations causing substantial yield losses. Overall, deep, closely spaced cross sub-soiling improved soil-root functioning and translated these gains into higher fruit retention and yield, providing a robust framework for optimising sub-soiling strategies in semi-arid cotton systems.

This study critically evaluates conventional, reduced, and zero tillage systems with a focus on soil and water conservation, residue management, and sustainability in global agriculture and the Indo-Gangetic Plains. A systematic narrative review approach was used, synthesizing peer-reviewed literature (1990-2025) from major scientific databases. Results indicate that zero tillage systems, particularly Happy Seeder-based practices, can enhance soil aggregation, increase infiltration, and improve moisture retention through residue mulching. Quantitative evidence suggests yield gains of 6.8-17%, cost reductions of up to 29%, irrigation savings of 20-30%, and greenhouse gas emission reductions exceeding 50% compared to conventional systems. However, outcomes vary across soil types, climatic conditions, and management practices. Key limitations include herbicide dependence, weed resistance, and socio-economic constraints affecting adoption. The study concludes that conservation tillage offers significant potential for climate-smart agriculture, but its effectiveness depends on region-specific adaptation, integrated nutrient and weed management, and supportive policy frameworks.

Optimizing tillage and fertilization practices is of vital importance for enhancing soil carbon retention, improving soil quality and increasing crop productivity in the intensive wheat (Triticum aestivum L.)–maize (Zea mays L.) double cropping system (WM). However, the combined effects of subsoiling (ST) and liquid manure (LM) application on yield sustainability and the dynamic changes in labile organic carbon (LOC) fractions (LOCs) remain insufficiently quantified in WM in the North China Plain (NCP). A two-year field experiment evaluated the responses of grain yields, the sustainable yield index (SYI), soil organic carbon (SOC), LOCs, C pool management indexes (CPMIs), and the soil quality index (SQI) to both patterns of tillage [conventional shallow rotary tillage (RT) and ST] and fertilization [conventional fertilization (CF), LM broadcast (LMB), and LM injection (LMI)] in WM in the NCP. Compared with RT, ST significantly enhanced crop grain yields (3.5~4.1%) and the annual SYI (4.1%) (p < 0.05). The contents of SOC, total labile OC (TLOC), high LOC (HLOC), and medium LOC (MLOC) and the values of SQI were higher in soil layers at both 0–20 cm and 20–40 cm under ST than those under RT. Compared with CF, LMI significantly enhanced grain yields (5.8~6.1%) and the annual SYI (5.4%). LMI significantly increased the contents of SOC, TLOC, HLOC, and MLOC and the SQI values in both soil layers relative to CF, while no significant difference was observed for grain yields, the annual SYI, and the SQI between LMB and CF. The higher contents of SOC and LOC led to an increase in the values of CPMIs based on TLOC (TCPMI), HLOC (HCPMI), and MLOC (MCPMI). The combination of both ST and LMI enhanced SOC retention through the increase in recalcitrant organic carbon (ROC) content and the transformation process of LOCs. It was obvious that HLOC and MLOC affected SOC, HCPMI, and MCPMI in the soil layers at both 0–20 cm and 20–40 cm, and thus can be regarded as sensitive indicators reflecting the dynamic changes in SOC and soil quality. Therefore, the combination of subsoiling and liquid manure injection can promote labile OC transformation, SOC retention, soil quality, and yield sustainability, providing an effective management strategy for the achievement of sustained agricultural production in the NCP or other regions with similar conditions.

Understanding the dynamics of soil organic carbon (SOC) in farmland is crucial for assessing soil health, quantifying ecosystem potential for SOC enrichment, and guiding sustainable agricultural management. Existing research on SOC sequestration and mineralization has focused mainly on the topsoil layer (0–20 cm), whereas systematic evidence on how deep SOC (>20 cm) responds to agricultural management, and on strategies to enhance deep carbon sequestration, remains limited. This study uses long-term fixed-site monitoring data from 120 farmland plots across 21 typical farmland ecosystem stations and farmland–complex ecosystem stations within the Chinese Ecosystem Research Network (CERN) over 17 years (2004–2020). Using spatial analysis, we characterize the spatiotemporal dynamics of SOC below 20 cm along soil profiles across seven major geographical zones in China. We then estimate the heterogeneous effects of fertilization and straw-management practices (S, straw returning; SCF, straw returning with chemical fertilizer; OF, organic fertilizer; OCF, organic fertilizer with chemical fertilizer), tillage modes, and farmland types on SOC in the 20–40 cm, 40–60 cm, and 60–100 cm layers using a panel fixed-effects model. The results indicate pronounced vertical heterogeneity in SOC below 20 cm and a clear spatial gradient. The 60–100 cm layer shows a significant increase in SOC content during the study period, with a cumulative increase of 4.07%. Relative to single organic inputs, the co-application of organic and inorganic materials improves deep soil SOC enhancement efficiency. Compared with reduced tillage and no-tillage, conventional tillage is less conducive to SOC enhancement in layers shallower than 60 cm, yet it has a significant positive impact on SOC in the 60–100 cm layer. Compared with dryland and irrigated land, paddy fields are less favorable for SOC enhancement below 20 cm. Consequently, regarding agricultural practice, a composite tillage regime combining “surface conservation tillage with periodic deep tillage” should be promoted to foster deep SOC enhancement.

Land use can strongly influence aggregate stability, a key factor in conserving soil organic carbon over extended periods. Therefore, the long-term effects of three different land-use types on aggregate stability (AS) and aggregate-associated organic carbon (AAOC) were assessed in this study. The study was conducted on the campus of Çukurova University, Adana, Türkiye. The land-use types were; arable land (AL, continuously used as cropland since 1974), olive orchard (OO, cultivated as olive trees since 1974), and eucalyptus plantation (EP, established in 1997). In June 2025, soil samples were collected from the surface horizon of each land-use type. The results showed that AS and AAOC differed significantly among the long-term different land-use types. In each land-use type, OO and EP significantly affected AAOC. The highest AS was obtained in OO and EP compared to AL, which is conventionally tilled. The land-use type EP had the highest OC (1.48%), which was 32.1% higher than OO (1.12%) and 80.5% higher than AL (0.82%), followed by OO and AL. The highest AAOC was determined in the 4–2 mm aggregate, followed by the 1–2 mm and 0.5–1 mm aggregates, respectively. The results indicated that orchard and plantation promoted improved aggregation and enhanced SOC retention within surface horizon, whereas conventional tillage showed reduced aggregate stability and carbon retention.

Trade-off analysis between soil organic carbon and maize yield under no-tillage: implication for sustainable cropland management.