Indaziflam is a relatively new herbicide that kills newly germinated plants. There is interest in using indaziflam to improve rangeland restoration but applying it around the time of seeding risks damaging seeded plants. A better strategy may be using indaziflam long before seeding to deplete weed seedbanks and then seeding after it dissipates. Dissipation rates vary and are difficult to predict, so testing is needed to determine whether indaziflam remains present. The manufacturer-recommended test involves seeding small indaziflam-treated areas and then monitoring for herbicide damage. A disadvantage here is that rangeland seeding is failure-prone, so seeded species can fail to emerge whether indaziflam is present or not. Another disadvantage is that test areas cannot be reliably evaluated until many months to a year after seeding, by which time evaluations are obsolete. We sought a more reliable, rapid bioassay. We gathered soil samples from nontreated and indaziflam-treated plots in two experiments treated 565 d and 204 d earlier. In these samples in a greenhouse, we planted seeds of native grasses ( Elymus lanceolatus [Scribn. & J.G. Sm.] Gould and Pascopyrum smithii [Rydb.] & Aacute;. L & ouml;ve) and an exotic invasive grass ( Bromus japonicus Thunb.) and then measured plant responses. Plant densities and heights were similar across experiments. Indaziflam reduced native grass density 50% +/- 8%, native grass height 74% +/- 6% (mean +/- SE), and exotic grass density and height nearly 100% ( p = five nontreated and treated soil samples. In addition to greenhouses, other well-illuminated areas held at 16-24 degrees C are sufficient for testing. (c) 2025 Published by Elsevier Inc. on behalf of The Society for Range Management.
The depth of seed burial and impact damage are critical indicators of sowing quality in wheat accelerated seeding technology. To investigate the factors influencing seed burial depth and impact damage, a simulation model of wheat seed impact and soil penetration was developed using EDEM (2018) software, and the motion of wheat seed impact into soil was simulated and analyzed to identify the main influencing factors of wheat seed impact into soil. Seeding velocity, wheat seed equivalent diameter, and soil surface energy were selected as experimental factors, while burial depth and maximum impact force were chosen as response indicators. Both single-factor tests and three-factor, three-level orthogonal tests were conducted. Single-factor simulations showed that burial depth increased with seeding velocity and seed diameter, but decreased with soil surface energy. In contrast, maximum impact force increased with velocity and diameter, peaking at low soil surface energy before declining beyond a threshold. The orthogonal test results indicated that a maximum burial depth of 26.37 mm and a maximum impact force of 0.0704 N were achieved when the wheat seed diameter was 4 mm, the seeding velocity was 65 m/s, and the soil surface energy was 0.5 J/m2. Bench tests were conducted to validate the simulation results further. The results of the bench tests were consistent with the simulation results, with relative deviations of less than 5%, indicating the reliability of the simulation outcomes. This experimental study has provided data and a theoretical basis for the selection of technical parameters and the design and application of accelerated sowing technology for wheat.
External-soil spray seeding technology is a widely used method for ecological slope protection, playing a significant role in mitigating soil erosion, landslides, and other geological challenges. However, research on the technical stability of external-soil spray seeding is limited, resulting in suboptimal protective effects and hindering broader application. This review highlights emerging research themes for advancing ecological slope stability, including: ecological substrate, vegetated ecosystem, the mechanical properties and hydrological characteristics of the external-soil spray seeding technology. The review identifies new research themes for developing futuristic ecological slopes can be summarized as: (1) whether or not to find the stability models on the shear strength and bond strength of the substrate under water saturation, (2) how to establish models with the effect of grassland ratio, slope angle, seeding amount, and planting season on the long-term growth of ecological slope protection, (3) how to improve quantitative mechanical models between the roots and soil, (4) how to propose the relevant analytical and numerical methods for root-soil-atmosphere. The findings offer valuable guidelines for improving ecological slope stability and advancing the application of external-soil spray seeding technology.
Coal waste, a by-product of coal extraction, adversely poses environmental hazards as it releases harmful substances into the air, water, and soil, damaging the ecosystem and localized biodiversity. The coal-to-energy sludge-seeded bioconversion shows its potential as an environmentally friendly technology to mitigate the harmfulness of coal-derived hazards. This study uses blended coal and anaerobic digestion sludge in batch reactors at a mesophilic temperature (35 degrees C) to generate methane-rich biogas for energy production and waste elimination. Nutrient solution and ethanol were added as stimuli to boost bioactivities and enhance gas production. These results showed the potential of lignite coal in biomethane generation over an extended period, even with a lower volume of sludge addition. Adding nutrients and ethanol enhances the ultimate biogas production as an extra feed for microorganisms and as a key parameter in increasing the bioavailability of coal. The ultimate biogas production from the kinetic model indicates a remarkable volume of 111504 mL/g-sludge using lignite with 20 mol ethanol compared to the blank reactor with 701 mL/g-sludge of biogas production. The intricate analysis of results highlights the complex interplay between coal, sludge, nutrients, and additives, where varying factors impact methane production rates. Despite challenges in interpreting data, this study underscores the potential for managing coal waste through wastewater utilization, transforming it into methane-rich biogas-a sustainable green technology for energy production.
Bio-tiles are a biobased alternative to conventional tiles that utilise a promising technology called microbially induced calcium carbonate (CaCO3) precipitation (MICP). This technology has low energy requirements and also sequesters carbon. Bio-tiles have been made in previous work using a submersion method, however, the process required additives such as 0.3 M magnesium chloride to achieve bio-tiles that meet international standards. The current study aimed to improve the bio-tile strength properties with CaCO3 crystal seeding and a pumping method instead of the use of magnesium that also increases ionic strength. With this technique, cementation solution containing the required calcium and urea for the MICP reaction was pumped through a sealed mould in a series of programmed treatments. The highest concentration of ureolytic Sporosarcina pasteurii with an effective urease activity of 40 mmol NH4-N/L center dot min was found to be most beneficial to the breaking strength of the bio-tiles, as were the shortest retention times of 1 h between treatments. Seeding with CaCO3 crystals offered significant benefit to the MICP process. Pre-seeding of the geotextiles was explored and the mass of seeds initially present on the geotextiles was found to have a direct improvement on the breaking strength of 21-82 %, increasing with seed loading. The highest CaCO3 seed loading tested of 0.072 g seeds/cm2 geotextile resulted in bio-tiles with a breaking strength of 940 +/- 92 N and a modulus of rupture of 16.4 +/- 1.7 N/mm2, meeting international targets for
Seashell powder calcined sludge cement (SCSC) is a new type of green low-carbon ternary cement prepared by using waste sludge and waste seashells. It reduces carbon emissions in the cement production industry and solves environmental problems such as serious soil-water-air pollution caused by long-term stockpiling of waste sludge and waste seashells, which are difficult to be utilized in a resourceful manner. However, the reduced clinker content results in lower early strength of SCSC, which limits the application of SCSC in applications requiring high early strength such as precast concrete specimens. In this paper, the effects of different dosage of C-S-H seeds on the hydration process, mechanical properties and microstructure of SCSC slurries were investigated. The results showed that C-S-H seeds significantly increased the 12-hour compressive strength of SCSC, and the 2 % addition of C-S-H seeds increased its compressive strength by 271 %, but had less effect on its later strength. The proportion of large pores in the sample with a 1 % addition of C-S-H seeds decreased by 1 %. At 12 hours, 2 % addition of C-S-H seeds increased its total hydration exotherm by 141 %. The addition of C-S-H seeds decreased the fluidity of the slurry but did not change the flow pattern of the slurry. The relationship between the rheological parameters of the slurry and the addition of C-S-H seeds was well fitted with a primary function, and the rheological equations of SCSC slurries with different additions of C-S-H seeds were obtained. The results of this paper can further broaden the application scenarios of SCSC and lay the foundation for the large-scale application of SCSC.
Stem mustard, the main raw material for pickled mustard tuber, is widely planted in Chongqing, China, and is an important local cash crop. Under the working conditions of sticky and wet soil in the Chongqing area, conventional furrow seeding has problems such as soil sticking to the furrow opener, poor mulching effect, etc. In this regard, this paper proposes the use of non-contact, soil-based, pneumatic shot seeding, in which seeds are shot into the soil to a predetermined depth by a high-speed air stream. The diameter of stem mustard seeds was found to be 1.33 mm, with a spherical rate of 95.32% using physical and mechanical properties. The high-speed camera test was used to determine the air pressure at the appropriate sowing depth, and the seed entry process was simulated by EDEM 2021 software, which analysed the movement process of the seed after entering the soil, and the structure of the seeder was designed based on the resulting test data. The structural parameters of the shot seeding device were analysed by a hydrodynamic simulation using Fluent 2022 R1 software and the following results were obtained: an outlet pipe diameter DC of 2 mm, mixing zone length H of 10 mm, mixing zone inlet diameter D of 15 mm, and steady-state gas flow rate of 80 m/s. Simulation seeding verification was conducted on the final determined structural parameters of the seeding device, and the simulation results showed that the seed velocity could reach 32.3 m/s. In actual experiments, it was found that when the vertical velocity of the seeds was greater than or equal to 26.59 m/s, the seeds could be completely and stably seeded into the soil. Therefore, the designed seeding device can meet the conditions of actual seeding experiments. In conclusion, this research offers a practical guideline for the rapid and precise sowing of stem mustard.
A seeding machine for planting potatoes in double rows on large ridges in the cold and arid regions of northwest China was designed and built at Gansu Agricultural University. The machine is capable to achieve the integrated operations of ridge formation, mulching, hole punching, and the precise covering of holes on the film. The key components were analyzed and designed, and the link lengths of the crank film-piercing and hole-punching mechanism were refined using MATLAB R2022a software. The structures and working parameters of the film-piercing and hole-punching mechanism, the dual-opening punching and seeding mechanism, the ridge-forming and soil-covering mechanism, and the seed-casting device were designed. The dynamics of the ridge-forming and soil-covering were simulated using the discrete element method to capture the effects of different machine parameters on the soil covering operation. Field tests showed that the full soil-covering rate of film holes, the qualified rate of hole spacing, the hole misalignment rate, the degree of damage to the light-receiving surface of the film, and the qualified rate of sowing depth under the film were 94.8%, 87.6%, 4.3%, 33.4%, and 95.6%, respectively. These indicators met the requirements of industry standards, and the test results met the design and actual operation requirements, enabling the integrated operations of ridge formation, mulching, hole punching, sowing on the film, and the accurate soil covering of the holes.
The new technique of filming in autumn and planting directly through the plastic film in spring is an effective method for water-saving and drought-resistant commercial potato production. However, there are currently no supporting film-drilling seeders available. To address this, a new potato seeder machine has been specifically designed for planting potatoes in the dryland, hilly, and mountainous areas of northwest China. This machine can perform top mulching and hole planting in both the autumn and spring seasons. This innovative potato seeder accomplishes several tasks simultaneously: seeding, inoculation (if desired), hole punching through the mulch film, seed placement, and soil covering. The machine features an optimized spoon-chain seeder with an eccentric coupling mechanism that ensures the hole-punching device stays perpendicular to the ground throughout planting, minimizing damage to the mulch film. Additionally, a dedicated seeding valve opening and closing mechanism was designed to extend the opening time of the hole-forming device's movable mouth beyond the potato's falling time, guaranteeing successful seed placement. Furthermore, a soil-covering device specifically designed for use with mulch film ensures proper soil retention after seeding. Through computer-aided design (RecurDyn V9R5 software) analysis, the hole-punching device's penetrating angle was optimized to minimize the tearing of the mulch film during entry into and exit from the soil. Rigorous field testing demonstrated the machine's effectiveness. The seeder achieved a 92% success rate for proper planting depth, an 88% success rate for accurate seed potato spacing, a 98% success rate for avoiding overplanting, and a 99% success rate for eliminating missed planting spots. These field test results meet or exceed national and industry standards, validating the machine's design goals. In essence, this innovative potato seeder, with its eccentric coupling mechanism, offers a one-pass solution for potato seeding, inoculation (optional), planting, and soil covering, significantly improving efficiency.
Slope revegetation by seeding works with herbaceous plants is widely employed to prevent road embankment from erosion damage. The Percentage of Vegetational Cover (PVC) is used as an indicator for the quality evaluation of the seeding works. However, the PVC is usually measured manually through visual inspection, and the measurement results of the same subject might not be constant. In the present study, RGB image analysis is applied to objectively measure the PVC to overcome this situation. Then, laboratory flume experiments are conducted to investigate the capability of the PVC obtained by RGB image analysis to predict the decrease of sediment erosion against concentrated flow. Two herbaceous plant species, Centipede Grass and White Clover, are employed in the experiments. The findings of the experiments are as follows: Declining trends of the sediment erosion are observed as the PVC increases or plant growth period becomes longer, and the trends are more correlated with the PVC with RGB image analysis than with plant growth period. The results indicate that RGB image analysis can be a useful and inexpensive tool for inspection of the seeding works with herbaceous plants.