Search Results (77)

Water deficiency and low water use efficiency severely constrain wheat yield in dryland regions. This study aimed to identify suitable tillage methods and straw management to improve dry matter production, grain yield, and water use efficiency of wheat in the dryland winter wheat–summer bean (hereafter referred to as wheat-soybean) double-cropping system. A long-term located field experiment (onset in October 2009) with two tillage methods—plowing (PT) and rotary tillage (RT)—and two straw management—no straw mulching (NS) and straw mulching (SM)—was conducted at a typical dryland in China. The wheat yield and yield component, dry matter accumulation and translocation characteristics, and water use efficiency were investigated from 2014 to 2018. Straw management significantly affected wheat yield and yield components, while tillage methods had no significant effect. Furthermore, the interaction of tillage methods and straw management significantly affected yield and yield components except for the spike number. RTSM significantly increased the spike number, grains per spike, 1000-grain weight, harvest index, and grain yield by 12.5%, 8.4%, 6.0%, 3.4%, and 13.4%, respectively, compared to PTNS. Likewise, RTSM significantly increased the aforementioned indicators by 14.8%, 10.1%, 7.5%, 3.6%, and 20.5%, compared to RTNS. Mechanistic analysis revealed that, compared to NS, SM not only significantly enhanced pre-anthesis and post-anthesis dry matter accumulation, and pre-anthesis dry matter tanslocation to grain, but also significantly improved pre-sowing water storage, water consumption during wheat growth, water use efficiency, and water-saving for produced per kg grain yield, with the greatest improvements obtained under RT than PT. Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) analysis confirmed RTSM’s yield superiority was mainly ascribed to straw-induced improvements in dry matter and water productivity. In a word, rotary tillage with straw mulching could be recommended as a suitable practice for high-yield wheat production in a dryland wheat-soybean double-cropping system. Full article

Soil organic carbon (SOC) mineralization plays the critical role of regulating carbon sequestration potential. This process is strongly influenced by agricultural practices, particularly tillage regimes and straw management. However, the complex interactions between tillage methods, straw types, and application rates in terms of SOC dynamics, especially in semi-arid agroecosystems like eastern Inner Mongolia, remain poorly understood. In this study, we assessed the combined effects of no tillage (NT) vs. rotary tillage (RT), three straw types (maize/MS, wheat/WS, and oilseed rape/OS), and three application rates (0.4%/low, 0.8%/medium, and 1.2%/high) on SOC concentration and mineralization using controlled laboratory incubation with soils from long-term plots. The key findings revealed that NT significantly increased the SOC concentration in the topsoil (0–20 cm) by an average of 14.5% compared to that in the RT. Notably, combining NT with medium-rate wheat straw (0.8%) resulted in the achievement of the highest SOC accumulation (28.70 g/kg). SOC mineralization increased with straw inputs, exhibiting significant straw type × rate interactions. Oilseed rape straw showed the highest specific mineralization rate (33.9%) at low input, while maize straw mineralized fastest under high input with RT. Therefore, our results demonstrate that combining NT with either 0.8% wheat straw or 1.2% maize straw represents an optimal application strategy, as the SOC concentration is enhanced by 12–18% for effective carbon sequestration in this water-limited semi-arid region. Therefore, optimizing SOC sequestration requires the integration of appropriate crop residue application rates and tillage methods tailored to different cropping systems. Full article

Excessive chemical fertilizers degrade soil and increase greenhouse gas (GHG) emissions. Organic substitution of nitrogen fertilizers is recognized as a sustainable agricultural-management practice, yet its dual role in carbon sequestration and emissions renders the net GHG balance (NGHGB) uncertain. To assess the GHG mitigation potential of organic substitution strategies, this study analyzed GHG fluxes, soil organic carbon (SOC) dynamics, indirect GHG emissions, and Net Primary Productivity (NPP) based on a long-term field positioning experiment initiated in 2016. Six fertilizer regimes were systematically compared: no fertilizer control (CK); only phosphorus and potassium fertilizer (PK); total chemical fertilizer (NPK); 1/3 chemical N substituted with sheep manure (OF1); dual substitution protocol with 1/6 chemical N substituted by sheep manure and 1/6 substituted by straw-derived N (OF2); complete chemical N substitution with sheep manure (OF3). The results showed that OF1 and OF2 maintained crop yields similar to those under NPK, whereas OF3 reduced yield by over 10%; relative to NPK, OF1, OF2, and OF3 significantly increased SOC sequestration rates by 50.70–149.20%, reduced CH₄ uptake by 7.9–70.63%, increased CO₂ emissions by 1.4–23.9%, decreased N₂O fluxes by 3.6–56.2%, and mitigated indirect GHG emissions from farm inputs by 24.02–63.95%. The NGHGB was highest under OF1, 9.44–23.99% greater than under NPK. These findings demonstrate that partial organic substitution increased carbon sequestration, maintained crop yields, whereas high substitution rates increase the risk of carbon emissions. The study results indicate that substituting 1/3 of chemical nitrogen with sheep manure in maize cropping systems represents an effective fertilizer management approach to simultaneously balance productivity and ecological sustainability. Full article

Pesticide residues pose risks to the environment and human health. Little is known about how tillage and straw management affect herbicide behavior in soil. This study investigated the effects of different tillage practices under varying straw incorporation scenarios on the degradation of five commonly used herbicides in a long-term experimental field located in the maize belt of Siping, Jilin Province. Post-harvest soil samples were analyzed for residual herbicide concentrations and basic soil physicochemical properties. A human health risk assessment was conducted, and a controlled incubation experiment was carried out to evaluate herbicide degradation dynamics under three management systems: straw incorporation with traditional rotary tillage (ST), straw incorporation with strip tillage (SS), and no-till without straw (CK). Residual concentrations of atrazine ranged from not detected (ND) to 21.10 μg/kg (mean: 5.28 μg/kg), while acetochlor showed the highest variability (2.29–120.61 μg/kg, mean: 25.26 μg/kg). Alachlor levels were much lower (ND–5.71 μg/kg, mean: 0.34 μg/kg), and neither nicosulfuron nor mesotrione was detected. Soil organic matter (17.6–20.89 g/kg) positively correlated with available potassium and acetochlor residues. Health risk assessments indicated negligible non-cancer risks for both adults and children via ingestion, dermal contact, and inhalation. The results demonstrate that tillage methods significantly influence herbicide degradation kinetics, thereby affecting environmental persistence and ecological risks. Integrating straw with ST or SS enhanced the dissipation of atrazine and mesotrione, suggesting their potential as effective residue mitigation strategies. This study highlights the importance of tailoring tillage and straw management practices to pesticide type for optimizing herbicide fate and promoting sustainable agroecosystem management. Full article

Exploring the mechanisms by which green agricultural production reduces emissions and enhances carbon sequestration in soil can provide a scientific basis for greenhouse gas reduction and sustainable development in farmland. This study uses a combination of meta-analysis and field experiments to evaluate the impact of different agricultural management practices and climatic conditions on soil organic carbon (SOC) and the emissions of CO₂ and CH₄, as well as the role of microorganisms. The results indicate the following: (1) Meta-analysis reveals that the long-term application of organic fertilizers in green agriculture increases SOC at a rate four times higher than that of chemical fertilizers. No-till and straw return practices significantly reduce CO₂ emissions from alkaline soils by 30.7% (p < 0.05). Warm and humid climates in low-altitude regions are more conducive to soil carbon sequestration. (2) Structural equation modeling of plant–microbe–soil carbon interactions shows that plant species diversity (PSD) indirectly affects microbial biomass by influencing organic matter indicators, mineral properties, and physicochemical characteristics, thereby regulating soil carbon sequestration and greenhouse gas emissions. (3) Field experiments conducted in the typical green farming research area of Chenzhuang reveal that soils managed under natural farming absorb CH₄ at a rate three times higher than those under conventional farming, and the stoichiometric ratios of soil enzymes in the former are close to 1. The peak SOC (19.90 g/kg) in the surface soil of Chenzhuang is found near fields cultivated with natural farming measures. This study provides theoretical support and practical guidance for the sustainable development of green agriculture. Full article

Increasing soil organic carbon (SOC) storage is essential for improving soil fertility and mitigating climate change. The priming effect, which is regulated by physical, chemical and microbial interactions, plays a pivotal role in SOC turnover. However, the fate of both native and newly added carbon under different tillage regimes remains unclear. To address this gap, a ¹³C-glucose labelling incubation experiment was conducted to assess SOC mineralization and priming effects under long-term tillage practices, including subsoiling with straw mulching (ST), no tillage with straw mulching (NT), and conventional tillage with straw removal (CT). The results demonstrated that conservation tillage (NT and ST) significantly reduced total SOC mineralization and glucose-derived CO₂ release compared to CT. Notably, the priming effect under CT was 19.5% and 24.7% higher than under NT and ST, respectively. In the early incubation stage, positive priming was primarily driven by microbial co-metabolism, while during days 1–31, microbial stoichiometric decomposition dominated the process. In addition, NT and ST treatments significantly increased the proportion of >250 μm aggregates and their associated carbon and nitrogen contents, thereby enhancing aggregate stability and physical protection of SOC. The priming effect observed under conservation tillage was strongly negatively related to aggregate stability and aggregate associated carbon content, whereas it was positively related to the β-glucosidase/Peroxidase ratio (BG/PER) and the subtraction value between carbon/nitrogen (R_C:N) and the carbon–nitrogen imbalance of the available resources (TER_C:N). Overall, our findings highlight that conservation tillage enhances SOC stability not only by improving soil physical structure but also by alleviating microbial stoichiometric constraints, offering a synergistic pathway for carbon retention and climate-resilient soil management. Full article

Nitrogen (N) and organic-source fertilizers in agriculture are important to sustain crop production for feeding the growing global population. However, their use can result in significant greenhouse gas (GHG) emissions, particularly carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O), which are important climate drivers. This review discusses the interactive effects, uncovering both additive and suppressive outcomes of emissions under various soil and climatic conditions. In addition to examining the effects of nitrogen and the nitrogen use efficiency (NUE), it is crucial to comprehend the mechanisms and contributions of organic fertilizers to GHG emissions. This understanding is vital for developing mitigation strategies that effectively reduce emissions while maintaining agricultural productivity. In this review, the current knowledge is utilized for the management of nitrogen practices, such as the optimization of fertilization rates, timing, and methods of application, in terms of the nitrogen use efficiency and the related GHG emissions. Moreover, we discuss the role of organic fertilizers, including straw, manure, and biochar, as a mitigation strategy in relation to GHG emissions through soil carbon sequestration and enhanced nutrient cycling. Important strategies such as crop rotation, tillage, irrigation, organic fertilizers, and legume crops are considered as suitable approaches for minimizing emissions. Even with the progress made in mitigating fertilizer-related emissions, research gaps remain, specifically concerning the long-term effect of organic fertilizers and the interactions between microbial communities in the soil and fertilization practices. Furthermore, the differences in application practices and environmental conditions present considerable obstacles to accurate emission quantification. This review underlines the importance of conducting more thorough research on the combined application of N and organic fertilizers in multiple cropping systems to evolve region-specific mitigation strategies. Full article

The European Commission’s ban on routine tail docking has prompted this retrospective observational study to evaluate the short-term effects of transitioning to a fully undocked system. Twenty-two farms were assessed during three subsequent phases: total tail docking (step 1), subgroups of undocked pigs (step 2), and fully undocked pigs (step 3). Farmers received training in long-tail management and independently implemented it on their own farms. However, straw provision as environmental enrichment was mandatory, at least supplied during periods of pigs’ restlessness. Overall, going through step 2 appears to be successful. However, transitioning to step 3 worsened mortality (p = 0.010) and the feed conversion ratio (p = 0.015) in weaners. Compared to step 1, the cost of producing 1 kg of meat in step 3 was 33.9% greater during weaning and 7.4% during fattening. Tail lesion prevalence at slaughter was greater in step 3 (41%), followed by step 2 (10%) and step 1 (1%). The hypothetical labour required to optimize straw management compared to the adopted system, ensuring its continuous availability, was estimated as 35 min/100 piglets/weaning cycle (EUR 4.37) and 10.5 h/100 pigs/fattening cycle (EUR 109). Under the conditions of this study, transitioning to a fully undocked system was not successful. Mandating only the non-continuous use of straw has proven insufficient, and greater efforts must be systematically implemented. Full article

Long-term excessive application of nitrogen fertilizers in sweet maize farmland in South China has led to low nitrogen absorption and high emissions of reactive nitrogen (RN). In this study, four kinds of organic materials, including maize straw, cow manure, biochar, and biogas residue, were applied to sweet maize farmland for three consecutive cropping seasons to substitute 20% of synthetic nitrogen fertilizer. We compared the effects of different nitrogen substitution practices on nitrogen use efficiency (NUE), nitrogen surplus (NSP), and nitrogen footprint (NF) in farmland, with conventional fertilization as the control (CK). Results demonstrated that nitrogen substitution practices increased crop nitrogen uptake by 18.80–52.37%, NUE by 16.00–43.03%, and nitrogen partial factor productivity (PFP_N) by 46.18–74.31%, while reducing nitrogen surplus and loss by 7.84–21.84% and 12.08–42.88%, respectively. From a life cycle assessment perspective, nitrogen footprint per unit area (NF_A) and per unit yield (NF_Y) decreased by 13.64–32.24% and 34.26–47.64%, respectively. The results demonstrated that partial substitution with organic fertilizers improved nitrogen utilization as well as reduced nitrogen surplus, loss and, footprint in the sweet maize cropping system in South China. Biochar substitution achieved the most significant improvements. This study provides a research basis for nitrogen management in the sweet maize cultivation system in South China and valuable information for achieving sustainable agricultural development in typical subtropical areas in East Asia. Full article

A reduction in emissions of nitrous oxide (N₂O), one of the three major greenhouse gases, is important for achieving environmental sustainability and carbon neutrality goals. Agricultural fields are the primary source of N₂O emissions, and their management measures influence greenhouse gas emission reductions and the greening of agriculture. Among these practices, cover cropping plays a key role in promoting sustainable agricultural production as a major cropping technique for efficient water use and increasing crop yields in water-scarce regions worldwide. The present paper systematically reviews the influence of various soil environmental factors, such as soil temperature, moisture, pH, carbon, and nitrogen contents, as well as nitrogen cycle-related enzymes, microorganisms and mulching practices, including general mulching and straw mulching, on N₂O emissions from agricultural fields. This review suggests that future research should explore the long-term effects of different mulching materials and their application rates and durations on soil N₂O emissions. Furthermore, a networked mathematical model for causal analysis should be employed in future research to elucidate the relationships among soil environmental factors, nitrogen cycle microorganisms, and soil N₂O production and consumption. These future studies will help to deepen our understanding of nitrogen cycling processes in agroecosystems with the aim of developing environmentally friendly agricultural technologies and promoting green and sustainable agricultural development. Full article

Soil mulching practices in apple orchards offer an effective solution to combat declining soil quality, restore land productivity, and boost apple yield. The kinetic parameters of soil enzymes, specifically the maximum reaction rate (V_max) and the Michaelis constant (K_m), are critical indicators of enzyme activity, while the temperature sensitivity (Q₁₀) reflects the thermal stability of the enzymatic reaction system. However, the effects of different mulching practices on soil enzyme kinetic parameters and their temperature sensitivity remain poorly understood, and there is no consensus regarding the most effective mulching strategies for soil conservation. To address this gap, we focused on a typical apple orchard ecosystem in the Loess Plateau region and investigated the responses of soil enzyme kinetic parameters and their temperature sensitivity to various mulching practices, including different cover materials, grass species for cover crops, and cover duration. Our results show that, among the mulching practices, both ryegrass (RE) and maize straw significantly enhanced the maximum enzyme catalytic reaction rates (V_max) and catalytic efficiency (K_cat) of β-glucosidase (BG), N-acetyl-β-glucosaminidase (NAG), and alkaline phosphatase (ALP). In contrast, black fabric (BF) reduced the temperature sensitivity of the enzyme system by decreasing V_max and K_cat. Among the grass species used for cover, crown vetch (CV) had the most pronounced effect on V_max, while long-term grass cover was more effective in improving the nutrient utilisation capacity of the soil enzyme system. Overall, maize straw and long-term grass cover were found to be the most effective in enhancing the soil enzyme system’s ability to decompose and utilise substrates efficiently. This study identifies soil nutrients as key factors influencing the temperature sensitivity of enzyme kinetics. Our findings provide a scientific basis for developing and applying orchard conservation practices and offer technical support for selecting and promoting soil management strategies that improve soil quality and contribute to the sustainable development of the apple industry in the Loess Plateau. Full article

Soil anaerobic ammonium oxidation (anammox) can eliminate reactive nitrogen (N) without generating nitrous oxide and is a key factor in N loss in agricultural ecosystems. Nevertheless, it remains unclear what determines the anammox rate and hzs gene abundance under various cropland management. This study synthesized 100 observations to elucidate the effects of cropland management (including biochar, manure, straw amendment, and N fertilization) on the anammox rate and hzs gene abundance and the governing factors of anammox processes from cropland systems. Our meta-analysis revealed that biochar addition significantly increased the anammox rate by 415%, while manure and N fertilization enhanced the anammox rate by 107% and 60%, respectively. The hzs gene abundance was increased by 240% and 68% under biochar amendment and N fertilization, respectively. Furthermore, biochar increased the anammox rate during the long-term duration (>10 years) at low N application rates and enhanced hzs gene abundance in acidic soil due to increased soil pH. For manure amendment and N fertilization, the anammox rate was significantly promoted in warm, wet climates with lower C/N and higher NH₄⁺-N content. The hzs gene abundance was enhanced in wetter environments (high MAP and aridity index) combined with higher NH₄⁺-N content. This study highlights that alkaline, humid, warm environments, lower C/N, and higher NH₄⁺-N play important roles in determining anammox rate and related bacterial activity. This study provides a new insight into understanding and potentially managing the effects of anammox in cropland cultivation. Full article

Background: Soil salinity poses a significant threat to agricultural lands by adversely affecting soil properties, crop productivity, and, consequently, global food security. This study evaluated the effects of date palm waste compost (C), applied alone or combined with biochar (BCC) or Ramial chipped wood (RCWC), on soil properties and barley yield under arid and saline conditions. Methods: A field experiment was performed in a completely random design with three replications. In addition to the unamended soil (control), treatments with compost (C), biochar + compost (BCC) and Ramial chipped wood + compost (RCWC) were tested. We monitored soil physico-chemical parameters, straw biomass, grain yield, and soluble sugar levels over two crop seasons. Results: All treatments enhanced soil fertility. However, the sodium adsorption ratio (SAR) and the cation ratio of soil structural stability (CROSS) increased in soils amended with compost alone in the second crop year. Barley (Hordeum vulgare L.) cultivated in soil amended with C and BCC produced 28% and 37% more dry biomass, respectively, in the second year, while no significant effects were observed in the first year. This may be attributed to the higher availability of nutrient content (N and P) in soils during the second year. In the first year, plants amended with BCC exhibited the highest accumulation of sucrose and fructose, with increases of up to 39% and 66%, respectively. Conclusions: Compost application did not affect barley yield during the first crop year, highlighting limited effects on soil fertility. However, C and BCC improved barley yield in the second year after application. No synergistic effect was observed between biochar, Ramial chipped wood, and compost. Future Perspective: Further studies should focus on the long-term effects of organic soil management, including salinity issues, to support sustainable agriculture in arid regions. Full article

Soil labile organic carbon (C) fractions play a key role in agricultural soil fertility. However, the effects of long-term organic substitution regimes on soil organic carbon (SOC), its labile fractions, stability, and vegetable yields as well as the relationships among these factors in the open-field are less well-studied. Hence, the objective of this study was to analyze the effects of long-term organic substitution regimes on SOC sequestration, labile C fractions [particulate organic C (POC), microbial biomass carbon (MBC), dissolved organic C (DOC), and readily oxidizable C (ROC)], SOC stability, the C pool management index (CMI), and vegetable yields in a long-term (13 years) open-field experiment. Five treatments were examined: 100% chemical nitrogen fertilizer (CN), substituting 25% of the chemical N with manure (MN) or straw (SN), and substituting 50% of the chemical N with manure (2MN) or manure plus straw (MSN). Compared to the CN, organic substitution treatments increased the average yields of vegetable, the SOC, the labile C fractions’ contents, and the C pool management index (CMI) to varying degrees, but only MSN reached significant levels for these factors. However, the MSN treatment had a significantly lower C stability index (SI) than the CN. ¹³C-NMR analyses also confirmed that organic substitution treatments increased the proportion of O-alkyl C and the OA/A, but reduced SOC stability. Pearson correlation analysis and the partial least squares path model indicated that labile C fractions were the mainly direct contributors to yield and SOC stability. Overall, substituting 50% of the chemical N with manure plus straw is a relatively ideal fertilization practice to improve vegetable yields and enhance C activity in an open field. Full article

The tillage method and straw returning are the two most important agronomic measures for crop production, but their combined effects on nutrient accumulation and utilization and grain yield in dryland winter wheat (Triticum aestivum L., namely wheat)–summer maize (Zea mays L., namely maize) double-cropping system are still poorly understood. The present study delves into the impact of the tillage method and straw returning on yield and nutrient accumulation and utilization in wheat–maize double-cropping system based on a field split-plot positioning experiment (started in October 2009). Three tillage methods—plowing (PT, 30–35 cm in depth), rotary tillage (RT, 12–15 cm in depth), no-tillage (NT)—and two straw management—zero straw returning (S0) and straw returning (SR)—were assigned to the main plots and subplots, respectively, thus encompassing six distinct treatments of PTS0, PTSR, RTS0, RTSR, NTS0, and NTSR. The grain yield and its components; the nitrogen (N), phosphorus (P), and potassium (K) accumulation at maturity; and the internal efficiency of N, P, and K in wheat and maize from 2018 to 2022 were investigated. The results indicated that in the experimental years, tillage methods and straw management significantly affected wheat, maize, and annual yield. Compared with NT, RT significantly increased wheat yield by 9.5% and maize K accumulation by 5.8%, and PT significantly increased wheat K accumulation by 11.1% and the yield and N, P, and K accumulation of maize by 6.3%, 7.8%, 8.9%, and 5.3%. Compared with RT, PT significantly increased yield and K accumulation in wheat and yield and N and P accumulation in maize. Compared with NTSR, PTSR significantly increased the yield and N, P, and K accumulation in wheat, but it did not affect yield and nutrient accumulation in maize; RTSR significantly increased wheat yield while it significantly decreased yield and N, P, and K accumulation in maize. Compared with RTSR, PTSR significantly increased the yield and N, P, and K accumulation by 4.0%, 19.5%, 19.6%, and 7.0% in wheat, respectively, and 7.5%, 6.1%, 13.3% and 13.6% in maize. Under the same tillage method, compared with S0, SR significantly increased crop yield and N, P, and K accumulation by 2.4–25.4%, 8.5–43.3%, 12.9–37.8%, and 11.0–51.0%, but it significantly reduced wheat K internal efficiency and maize N, P, K internal efficiency. The effectiveness of straw management on crop yield and N, P, and K accumulation was greater than that of tillage methods. Therefore, the combination of plowing tillage with straw returning (PTSR) is an effective tactic to promote crop yield in dryland wheat–maize double-cropping system. This study offered insights for achieving high yield by regulating the accumulation and internal efficiency of plant N, P, and K nutrients in wheat–maize double-cropping system in drought-prone areas and environments similar to the study areas. Full article