Biological N fixation but not mineral N fertilization enhances the accumulation of N in peanut soil in maize/peanut intercropping system

Legume/cereal intercropping has the potential to maximize the use of resources to raise yields due to enhanced nitrogen (N) fixation by legume root nodules, while high N fertilization may inhibit the nodulation of legume. However, whether legume/cereal intercropping can promote the accumulation of soil N storage with N fertilization and its underlying mechanism are less clear. Here, we evaluated the long-term (5 years) effects of maize/peanut intercropping and mineral N fertilization on peanut soil total N content and soil N cycling functional genes. The experiment includes two planting patterns (peanut maize intercropping and peanut monocropping) with three N fertilization rates (0, 150, and 300 kg N ha−1). Intercropping increased soil total N content (STN) by average 18.2%, and the positive effect of intercropping on STN decreased with N application rate. Highest N application decreased the nodule fresh weight (NFW) by 64.3% and 46.0% in intercropping and monocropping system, respectively. However, intercropping has no effect on NFW. Intercropping increased the nifH gene abundance by average 26.5%. SEM analysis indicated that NFW and nifH gene abundance combined can explain 46% of the variance of STN. Our results indicate that biological N fixation but not mineral N fertilization enhances the accumulation of N in soil planted with peanut in maize/peanut intercropping system.info:eu-repo/semantics/publishedVersio

Biodegradable Mulching Films Based on Polycaprolactone and Its Porous Structure Construction

Polycaprolactone (PCL) is one of the promising linear aliphatic polyesters which can be used as mulching film. Although it has suitable glass transition temperature and good biodegradability, further practical applications are restricted by the limited temperature-increasing and moisturizing properties. The rational design of the PCL structure is a good strategy to enhance the related properties. In this study, thermally-induced phase separation (TIPS) was introduced to fabricate a PCL nanoporous thin film. The introduction of a nanoporous structure on the PCL surface (np-PCL) exhibited enhanced temperature-increasing and moisturizing properties when used as mulch film. In detail, the average soil temperature of np-PCL was increased to 17.81 °C, when compared with common PCL of 17.42 °C and PBAT of 17.50 °C, and approaches to PE of 18.02 °C. In terms of water vapor transmission rate, the value for np-PCL is 637 gm−2day−1, which was much less than the common PCL of 786 and PBAT of 890 gm−2day−1. As a result, the weed biomass under the np-PCL was suppressed to be 0.35 kg m−2, almost half of the common PCL and PBAT. In addition, the np-PCL shows good thermal stability with an onset decomposition temperature of 295 °C. The degradation mechanism and rate of the np-PCL in different pH environments were also studied to explore the influence of nanoporous structure. This work highlights the importance of the nanoporous structure in PCL to enhance the temperature-increasing and moisturizing properties of PCL-based biodegradable mulching film

Effects of Corn Stalks and Urea on N2O Production from Corn Field Soil

Returning corn stalks to the field is an important and widely used soil management practice which is conducive to the sustainable development of agriculture. In this study, the effects of corn stalks and urea on N2O production in corn field soil were investigated through a 21-day incubation experiment. This study showed that increasing amounts of urea added to soil with a history of corn cultivation leads to increasing overall N2O emissions, by increasing both the intensity and the duration of emissions. Although N2O production was affected primarily by urea-derived NH4+-N and NO3−-N, its main source was native soil nitrogen, which accounted for 78.5 to 94.5% of N2O. Returning corn stalk residue to the field reduced the production of N2O, and the more urea was applied, the stronger the effect of corn residue on reducing N2O emissions. Combining the application of corn stalks and urea could reduce the concentration of NH4+-N and NO3−-N derived from urea, and then reduce the substrate required for N2O production in nitrification and denitrification processes. In addition, the combined application of corn stalks and urea could effectively inhibit the abundance of key N2O-producing genes AOA amoA, nirS and nirK

A two-step approach for fluidized bed granulation in pharmaceutical processing: Assessing different models for design and control

<div><p>Various modeling techniques were used to understand fluidized bed granulation using a two-step approach. First, Plackett-Burman design (PBD) was used to identify the high-risk factors. Then, Box-Behnken design (BBD) was used to analyze and optimize those high-risk factors. The relationship between the high-risk input variables (inlet air temperature X₁, binder solution rate X₃, and binder-to-powder ratio X₅) and quality attributes (flowability Y₁, temperature Y₂, moisture content Y₃, aggregation index Y₄, and compactability Y₅) of the process was investigated using response surface model (RSM), partial least squares method (PLS) and artificial neural network of multilayer perceptron (MLP). The morphological study of the granules was also investigated using a scanning electron microscope. The results showed that X₁, X₃, and X₅ significantly affected the properties of granule. The RSM, PLS and MLP models were found to be useful statistical analysis tools for a better mechanistic understanding of granulation. The statistical analysis results showed that the RSM model had a better ability to fit the quality attributes of granules compared to the PLS and MLP models. Understanding the effect of process parameters on granule properties provides the basis for modulating the granulation parameters and optimizing the product performance at the early development stage of pharmaceutical products.</p></div

Standard Pareto chart showing the effects of various process factors on (a) flowability, (b) temperature, (c) moisture, (d) aggregation index, and (e) compactability.

<p>Standard Pareto chart showing the effects of various process factors on (a) flowability, (b) temperature, (c) moisture, (d) aggregation index, and (e) compactability.</p

Effects of subsoiling on maize yield and water-use efficiency in a semiarid area

A 3-year field research was conducted to investigate the effect of four subsoiling methods on maize yield and water use efficiency. These four subsoiling methods included bulk subsoiling in autumn (BS), annual ridge subsoiling in autumn, annual furrow subsoiling in early summer, and interannual alternate zone subsoiling (AS), which were compared with rotary tillage in spring. The results suggested that the bulk density of the soil was alternately changed by AS, but AS had limited effect on the average water storage in the soil. Overall, soil tilled by BS and AS maintained a high water-holding capacity, which could stabilize the yield of maize under varying rainfall across different years. Maize under the AS subsoiling method maintained a relatively higher production capacity and water-use efficiency compared with those under the other three types of subsoiling methods

Fall Straw Incorporation with Plastic Film Cover Increases Corn Yield and Water Use Efficiency under a Semi-Arid Climate

Corn straw incorporation in soil has been regarded as an environment-friendly approach for straw utilization. However, straw incorporation has been a challenge under a cold and dry climate due to slow decomposition. This field study was to use a novel approach to incorporate corn straw into the soil during the fall season with a plastic film cover in an effort to enhance the straw degradation, soil water use efficiency, and corn growth and yield. Two-year field experiments were conducted in northeast China to investigate the effects of four treatments on soil properties and corn growth: (1) straw incorporation with film cover, (2) straw incorporation only, (3) film cover only, and (4) control. Soils and corn plants were collected during the growing season and analyzed for soil temperature and moisture, straw degradation, corn biomass, grain yield, and water use efficiency. Results indicated that straw incorporation with film cover increased grain yield by 53% as compared to straw incorporation only and by 102% to control. The straw decomposition under film cover was 20% faster, significantly higher than that of the straw incorporation treatment. In all cases, soil water content before planting, corn water uptake, and corn water use efficiency under straw incorporation with film cover were significantly higher than straw incorporation and control. Surface film cover resulted in 10-day earlier corn tasseling in compared to treatments without film cover. This field study demonstrated that straw incorporation with film cover would enhance straw degradation in soil, improve soil properties, and increase corn yield and water use efficiency, which could be potentially used as a sustainable soil management practice in northeast China

The Plackett-Burman experimental design and response variables.

<p>The Plackett-Burman experimental design and response variables.</p

Fall Straw Incorporation with Plastic Film Cover Increases Corn Yield and Water Use Efficiency under a Semi-Arid Climate

Corn straw incorporation in soil has been regarded as an environment-friendly approach for straw utilization. However, straw incorporation has been a challenge under a cold and dry climate due to slow decomposition. This field study was to use a novel approach to incorporate corn straw into the soil during the fall season with a plastic film cover in an effort to enhance the straw degradation, soil water use efficiency, and corn growth and yield. Two-year field experiments were conducted in northeast China to investigate the effects of four treatments on soil properties and corn growth: (1) straw incorporation with film cover, (2) straw incorporation only, (3) film cover only, and (4) control. Soils and corn plants were collected during the growing season and analyzed for soil temperature and moisture, straw degradation, corn biomass, grain yield, and water use efficiency. Results indicated that straw incorporation with film cover increased grain yield by 53% as compared to straw incorporation only and by 102% to control. The straw decomposition under film cover was 20% faster, significantly higher than that of the straw incorporation treatment. In all cases, soil water content before planting, corn water uptake, and corn water use efficiency under straw incorporation with film cover were significantly higher than straw incorporation and control. Surface film cover resulted in 10-day earlier corn tasseling in compared to treatments without film cover. This field study demonstrated that straw incorporation with film cover would enhance straw degradation in soil, improve soil properties, and increase corn yield and water use efficiency, which could be potentially used as a sustainable soil management practice in northeast China

Contour plots showing the effects of X₁ and X₃ on granule residual MC obtained by using: (a) RSM, (b) PLS, and (c) MLP (X₅ = 11.5).

<p>Contour plots showing the effects of X₁ and X₃ on granule residual MC obtained by using: (a) RSM, (b) PLS, and (c) MLP (X₅ = 11.5).</p