Rapid detection of fertilizer information based on Raman spectroscopy and machine learning.

The rapid detection of fertilizer nutrient information is a crucial element in enabling intelligent and precise variable fertilizer application. However, traditional detection methods possess limitations, such as the difficulty in quantifying multiple components and cross-contamination. In this study, a rapid detection method was proposed, leveraging Raman spectroscopy combined with machine learning, to identify five types of fertilizers: K2SO4, (CO(NH2)2, KH2PO4, KNO3, and N:P:K (15-15-15), along with their concentrations. Qualitative and quantitative models of fertilizers were constructed using three machine learning algorithms combined with five spectral preprocessing methods. Two variable selection methods were used to optimize the quantitative model. The results showed that the classification accuracy of the five fertilizer solutions obtained by random forest (RF) was 100 %. Moreover, in terms of regression, partial least squares regression (PLSR) outperformed extreme learning machine (ELM) and least squares support vector machine (LSSVM), yielding prediction Rp2 within the range of 0.9843-0.9990 and a root mean square error in the range of 0.0486-0.1691. In addition, this study evaluated the impact of different water types (deionized water, well water, and industrial transition water) on the detection of fertilizer information via Raman spectroscopy. The results showed that while different water types did not notably affect the identification of fertilizer nutrients, they did exert a pronounced effect on the quantification of concentrations. This study highlights the efficacy of combining Raman spectroscopy with machine learning in detecting fertilizer nutrients and their concentration information effectively.

Combining slow-release fertilizer and plastic film mulching reduced the carbon footprint and enhanced maize yield on the Loess Plateau.

Agricultural practices significantly contribute to greenhouse gas (GHG) emissions, necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production. Plastic film mulching is commonly used in the Loess Plateau region. Incorporating slow-release fertilizers as a replacement for urea within this practice can reduce nitrogen losses and enhance crop productivity. Combining these techniques represents a novel agricultural approach in semi-arid areas. However, the impact of this integration on soil carbon storage (SOCS), carbon footprint (CF), and economic benefits has received limited research attention. Therefore, we conducted an eight-year study (2015-2022) in the semi-arid northwestern region to quantify the effects of four treatments [urea supplied without plastic film mulching (CK-U), slow-release fertilizer supplied without plastic film mulching (CK-S), urea supplied with plastic film mulching (PM-U), and slow-release fertilizer supplied with plastic film mulching (PM-S)] on soil fertility, economic and environmental benefits. The results revealed that nitrogen fertilizer was the primary contributor to total GHG emissions (≥71.97%). Compared to other treatments, PM-S increased average grain yield by 12.01%-37.89%, water use efficiency by 9.19%-23.33%, nitrogen accumulation by 27.07%-66.19%, and net return by 6.21%-29.57%. Furthermore, PM-S decreased CF by 12.87%-44.31% and CF per net return by 14.25%-41.16%. After eight years, PM-S increased SOCS (0-40 cm) by 2.46%, while PM-U decreased it by 7.09%. These findings highlight the positive effects of PM-S on surface soil fertility, economic gains, and environmental benefits in spring maize production on the Loess Plateau, underscoring its potential for widespread adoption and application.

Eco-friendly natural rubber-based hydrogel loaded with nano-fertilizer as soil conditioner and improved plant growth.

This study addresses the dual challenge of agricultural cost and waste management by harnessing agrarian waste to produce nano-fertilizers (NF) to enhance crop yield while mitigating environmental impacts. Recognizing the limitations of traditional hydrogels' non-biodegradability and their inability to sustain root zone moisture and nutrient levels, we developed an LNR/AAc/pectin hydrogel. This innovative hydrogel offers a viable solution that provides a consistent NF supply and improves water retention efficiently. Additionally, we utilized Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy-energy dispersive x-ray (SEM-EDX), and thermogravimetric analysis (TGA) to analyze the hydrogel's structure, stability, and form. Transmission electron microscopy (TEM) and X-ray fluorescence spectroscopy (XRF) were employed to ascertain the NF concentration. The optimization of the hydrogel's swelling and NF release was conducted through a 5-level, 2-factor Response Surface Methodology (RSM), focusing on the effects of the AAc: LNR ratio and pectin weight while maintaining constant concentrations of potassium persulfate (KPS) and MBA. Results revealed a high correlation between predicted and experimental values, with determination coefficients (R2) of 0.9982 for swelling and 0.9979 for NF release. Furthermore, the hydrogel exhibited a 96.30 % biodegradation rate after 120 days of soil burial. Our findings demonstrate the hydrogels' potential to significantly impact farming and gardening by ensuring a sustainable supply of nutrients to enhance soil moisture retention.

Effects of the supernatant of Chlorella vulgaris cultivated under different culture modes on lettuce (Lactuca sativa L.) growth.

CO2 capture by microalgae is a feasible strategy to reduce CO2 emissions. However, large amounts of cell-free supernatant will be produced after microalgal harvesting, which may be harmful to the environment if it is disorderly discharged. In this study, Chlorella vulgaris (C. vulgaris) was cultivated under three common cultivation modes (autotrophic culture (AC), heterotrophic culture (HC) and mixotrophic culture (MC)), and the obtained supernatant was used as fertilizer to investigate its effect on the growth of lettuce. The biomass concentration of C. vulgaris cultivated under MC and HC was 3.25 and 2.59 times that of under AC, respectively. The contents of macronutrients in supernatant obtained from AC were higher than those of MC and HC. However, the contents of amino acids and hormones in supernatant obtained from MC and HC were higher than those of AC. The fresh shoot weight, fresh root weight and root length of lettuce treated with supernatant were significantly higher than that of control treatment. In addition, the contents of chlorophyll, soluble sugar and soluble protein in lettuce treated with supernatant were also higher than that of control treatment. However, the contents of nitrate in lettuce treated with supernatant was lower than that of control treatment. These results showed that the supernatant could promote the growth of lettuce and was a potential of fertilizer for crop planting.

The effect of novel biotechnological vermicompost on tea yield, plant nutrient content, antioxidants, amino acids, and organic acids as an alternative to chemical fertilizers for sustainability.

In this study, the performance of a novel organic tea compost developed for the first time in the world from raw tea waste from tea processing factories and enriched with worms, beneficial microorganisms, and enzymes was tested in comparison to chemical fertilizers in tea plantations in Rize and Artvin provinces, where the most intensive tea cultivation is carried out in Turkey. In the field trials, the developed organic tea vermicompost was incorporated into the root zones of the plants in the tea plantations in amounts of 1000 (OVT1), 2000 (OVT2) and 4000 (OVT4) (kg ha-1). The experimental design included a control group without OVT applications and positive controls with chemical fertilizers (N: P: K 25:5:10, (CF) 1200 kg ha-1) commonly used by local growers. The evaluation included field trials over two years. The average yields obtained in two-year field trials in five different areas were: Control (6326), OVT1 (7082), OVT2 (7408), OVT4 (7910), and CF (8028) kg ha-1. Notably, there was no significant statistical difference in yields between the organic (at 4000 kg ha-1 ) and chemical fertilizers (at 1200 kg ha-1). The highest nutrient contents were obtained when CF and OVT4 were applied. According to the average values across all regions, the application of OVT4 increased the uptake of 63% N, 18% K, 75% P, 21% Mg, 19% Na, 29% Ca, 28% Zn, 11% Cu and 24% Mn compared to the control group. The application of chemical fertilizers increased the uptake of 75% N, 21% K, 75% P, 21% Mg, 28% Na, 27% Ca, 30% Zn, 18% Cu and 31% Mn compared to the control group. The organic fertilizer treatment had the lowest levels of antioxidants compared to the control groups and the chemical fertilizers. It was also found that the organic fertilizer increased the levels of amino acids, organic acids and chlorophyll in the tea plant. Its low antioxidant activity and proline content prepared them for or protected them from stress conditions. With these properties, the biotechnologically developed organic tea compost fertilizer has proven to be very promising for tea cultivation and organic plant production.

Maize/soybean intercropping with nitrogen supply levels increases maize yield and nitrogen uptake by influencing the rhizosphere bacterial diversity of soil.

Introduction: Intercropping practices play a crucial role in enhancing and maintaining the biodiversity and resiliency of agroecosystems, as well as promoting stable and high crop yields. Yet the relationships between soil nitrogen, microbes, and yield in maize cultivated under maize/soybean intercropping systems remain unclear. Methods: To fill that knowledge gap, here we collected maize rhizosphere soil at the staminate stage after 6 consecutive years of maize/soybean intercropping, to investigate how intercropping and nitrogen application rates affected nitrogen utilization by crops and soil microbial community composition and function. We also examined correlations of those responses with yields, to clarify the main ways that yield is enhanced via intercropping and by nitrogenous fertilizer gradient changes generated by different nitrogen application rates. Results: The amount of applied fertilizer was 240 kg N ha-1 was best for obtaining a high maize yield and also led to the greatest nitrogen-use efficiency and bacterial diversity. Under the same N application rate, intercropping increased the maize yield by 31.17% and soil nitrogen (total, ammonium and nitrate nitrogen) by 14.53%, on average, in comparison to monocropping. The enrichment of Gemmatimonas and Bradyrhizobium significantly increased the soil nitrogen content, and a greater relative abundance of Sphingomonas and Gemmatimonas increased the maize yield, whereas enrichment of Candidatus_Udaeobacter and Bradyrhizobium decreased it. The benefits of intercropping mainly arise from augmenting the abundance of beneficial microorganisms and enhancing the efficiency of N use by crop plants. Discussion: This study's findings are of key importance to bolster the stability of agro-ecosystems, to guide the scientific rational use of nitrogen fertilizers, and to provide a sound theoretical basis for achieving the optimal management of intensive crop-planting patterns and green sustainable development.

Insect frass fertilizer as a regenerative input for improved biological nitrogen fixation and sustainable bush bean production.

Bush bean (Phaseolus vulgaris L.) production is undermined by soil degradation and low biological nitrogen fixation (BNF) capacity. This study evaluated the effect of black soldier fly frass fertilizer (BSFFF) on bush bean growth, yield, nutrient uptake, BNF, and profitability, in comparison with commercial organic fertilizer (Phymyx, Phytomedia International Ltd., Kiambu, Kenya), synthetic fertilizer (NPK), and rhizobia inoculant (Biofix, MEA Fertilizers, Nairobi, Kenya). The organic fertilizers were applied at rates of 0, 15, 30, and 45 kg N ha-1 while the NPK was applied at 40 kg N ha-1, 46 kg P ha-1, and 60 kg K ha-1. The fertilizers were applied singly and in combination with rhizobia inoculant to determine the interactive effects on bush bean production. Results showed that beans grown using BSFFF were the tallest, with the broadest leaves, and the highest chlorophyll content. Plots treated with 45 kg N ha-1 BSFFF produced beans with more flowers (7 - 8%), pods (4 - 9%), and seeds (9 - 11%) compared to Phymyx and NPK treatments. The same treatment also produced beans with 6, 8, and 18% higher 100-seed weight, compared to NPK, Phymyx, and control treatments, respectively. Beans grown in soil amended with 30 kg N ha-1 of BSFFF had 3-14-fold higher effective root nodules, fixed 48%, 31%, and 91% more N compared to Phymyx, NPK, and rhizobia, respectively, and boosted N uptake (19 - 39%) compared to Phymyx and NPK treatments. Application of 45 kg N ha-1 of BSFFF increased bean seed yield by 43%, 72%, and 67% compared to the control, NPK and equivalent rate of Phymyx, respectively. The net income and gross margin achieved using BSFFF treatments were 73 - 239% and 118 - 184% higher than the values obtained under Phymyx treatments. Our findings demonstrate the high efficacy of BSFFF as a novel soil input and sustainable alternative for boosting BNF and improving bush bean productivity.

Fertilizer-driven FO and MD integrated process for shale gas produced water treatment: Draw solution evaluation and PAC enhancement.

It is a great challenge for effective treatment of shale gas produced water (SGPW), a typical industrial wastewater with complex composition. Single forward osmosis (FO) or membrane distillation (MD) process has been widely used for desalination of SGPW, with membrane fouling not well addressed. Fertilizer draw solution (DS) with high osmotic pressure is less likely to cause FO fouling and can be used for irrigation. An integrated process using fertilizer-driven FO (FDFO) and MD process was proposed for the first time for SGPW treatment, and characteristics of fertilizer DS and powdered activated carbon (PAC) enhancement were assessed. The DS using KCl and (NH4)2SO4 had high MD fluxes (36.8-38.8 L/(m2·h)) and low permeate conductivity (below 50 µS/cm), increasing the contact angle of the MD membrane by 113 % than that without FO, while the DS using MgCl2 and NH4H2PO4 produced a lower reverse salt flux (0.9-3.2 g/(m2·h)). When diluted DS was treated using PAC, the MD permeate conductivity was further reduced to 35 µS/cm without ammonia, and the membrane hydrophobicity was maintained to 71-83 % of the original. The mechanism of the FDFO-MD integrated process for mitigating MD fouling and improving permeate quality was analyzed, providing guidance for efficient SGPW treatment.

Variations in the level of available phosphorus with changes in the status of water-soluble organic matter derived from different organic materials in soil.

The combined application of organic material and phosphorus fertilizer is an effective method to enhance phosphorus use efficiency for plant growth. This is partly because the presence of water-soluble organic matter (WSOM) derived from different organic materials can enhance the level of available phosphorus in the soil; however, it is poorly understood how this level varies with changes in the WSOM status (i.e., decomposed, dissolved, and retained) in the soil depending on WSOM types. This study aimed to (i) understand how changes in the WSOM status enhances the available phosphorus level in the soil, and (ii) determine the WSOM type that contributes to such enhancement. The incubation test showed that fractions of 73%-92% and 8%-27% of WSOM-derived organic carbon were retained and dissolved, respectively, at the beginning of incubation, while 31%-45% was decomposed during the incubation period. The WSOM derived from cattle manure compost (CM) and sewage sludge compost (SSC) that was initially retained was maintained until the late stage of the incubation test, whereas that derived from hydrothermal decomposed liquid fertilizer (HDLF) was rapidly desorbed during the first 14 days of the incubation period. The available phosphorus level was higher under the combined application of CM- and SSC-derived WSOM than under the single phosphorus application throughout the incubation period, while it was high only during the first 3 days of incubation under the application of HDLF-derived WSOM. The amounts of retained organic carbon at each sampling point during the incubation period compared to those at the beginning were positively and linearly correlated to the available phosphorus levels that were enhanced by the WSOM present in the soil. This study for the first time provides quantitative experimental evidence that 1) the longer the WSOM continues to be retained, the higher the amount of available phosphorus remaining in the soil, and 2) the available phosphorus level decreases with WSOM sorption or decomposition. Furthermore, it was shown that highly humified WSOM has a great potential for the maintenance of higher available phosphorus levels. This study provides the insight that a combined application of highly humified organic materials with a chemical fertilizer is necessary for not only cost effective but also sustainable fertilization design.

Tracking Carbon and Ammonia Emission Flows of China's Nitrogen Fertilizer System: Implications for Domestic and International Trade.

China is the world's largest producer, consumer, and exporter of synthetic nitrogen (N) fertilizer. To assess the impact of domestic demand and international exports, we quantified the life-cycle CO2eq and ammonia (NH3) emissions by tracking carbon (C) and nitrogen (N) flows from coal/gas mining through ammonia production to N fertilizer production, application, and export. In 2020, China's N fertilizer system emitted 496.04 Tg of CO2eq and 3.74 Tg of NH3, with ammonia production and N fertilizer application processes contributing 36 and 85% of the life-cycle CO2eq and NH3 emissions, respectively. As the largest importers of N fertilizer, India, Myanmar, South Korea, Malaysia, and the Philippines collectively shifted 112.41 Tg of CO2eq. For every ton of N fertilizer produced and used in China, 16 t of CO2eq and 0.18 t of NH3 were emitted, compared to 9.7 t of CO2eq and 0.13 t of NH3 in Europe. By adopting currently available technologies, improving N fertilizer utilization efficiency and employing nitrification inhibitors could synergistically reduce CO2eq emissions by 20% and NH3 emissions by 75%, while energy transformation efforts would primarily reduce CO2eq emissions by 59%. The production of ammonia using green electricity or green hydrogen could significantly enhance the decarbonization of China's N fertilizer system.

Modeling the response of sesame (Sesamum indicum L.) to different soil fertility levels under rain-fed conditions in the semi-arid areas of western Tigray, Ethiopia.

Sesame, a crucial oilseed crop in Ethiopia, ranks second only to coffee in its importance as an exported agricultural commodity. However, inadequate soil fertility management has hampered its productivity despite its substantial international market demand. Hence, this study was conducted to model the response of sesame to different nitrogen fertilizer levels using the AquaCrop model, and to assess the capability of the model as a decision-support tool for optimizing soil fertility management strategies in the study area. The experiment was laid out in a randomized complete block design, consisting of four nitrogen fertilizer rates (0, 23, 46, and 69 kg/ha nitrogen) and three distinct sesame varieties (Setit-1, Setit-2, and Humera-1). Over the course of the three cropping seasons, data on soil physical and chemical properties, crop growth, yield and yield components were collected for each treatment. Evaluation of model performance relied upon established metrics of coefficient of determination (R2), root mean square error (RMSE), normalized root mean square error (N-RMSE), model efficiency (E), and degree of agreement (D). Analysis of results revealed the AquaCrop model appropriately calibrated for simulation of soil water content, showing R2 values ranging from 0.92 to 0.98, RMSE values varying from 6.5 to 13.9 mm, E values from 0.78 to 0.94, and D values from 0.95 to 0.99. Similarly, simulation outputs for aboveground biomass (AB) demonstrated good accuracy of the model, with R2 values varying from 0.92 to 0.98, RMSE values ranging from 0.33 to 0.54 tons/ha, and D values from 0.9 to 0.98. Notable accuracy was also observed in the simulation of canopy cover (CC), revealing R2 values between 0.95 and 0.99, and RMSE values ranging from 5.3 to 8.6 %. In conclusion, this study substantiates the successful calibration and validation of the AquaCrop model for predicting sesame response to diverse nitrogen fertilizer levels. The performance of the model in predicting soil water content, CC, AB, and yield highlights its potential as a valuable tool for optimizing soil fertility management and enhancing sesame cultivation practices in Ethiopia.

Transcriptome and metabolism study reveals impact of nitrogen fertilizer on triticale.

Autumn-sown forage triticale can effectively leverage the optimal light and heat conditions in Ningxia, a region that boasts an abundance of light and heat resources sufficient for a single seasonal crop, but limited for two seasons. This not only fully utilizes the limited growing season but also significantly improves grass yield and economic efficiency per unit area. To enhance triticale yield in low-light and low-temperature environments, we investigated the impact of applying different concentrations of nitrogen fertilizer on triticale forage yield. Our findings revealed that nitrogen fertilizer application significantly increased triticale biomass, with the N4 treatment group exhibiting the most profound effect. To further explore the mechanisms behind nitrogen fertilizer's regulation of triticale growth and development, we conducted transcriptomic and metabolomic studies. These studies revealed that nitrogen fertilizer application significantly heightened transcription activity and protein synthesis in triticale, fostering the development of its seeds. Additionally, appropriate concentrations of nitrogen fertilizer significantly promoted photosynthesis. Metabolomic analysis revealed that nitrogen fertilizer application increased the levels of proline and O-phosphoethanolamine, enhancing triticale's stress resistance and supporting its growth and development under adverse conditions.

Exploring the mechanisms of organic fertilizers on Cd bioavailability in rice fields: Environmental behavior and effect factors.

The problem of paddy Cadmium (Cd) contamination is currently the focus of global research. Earlier researches have confirmed that utilization of organic fertilizers regulates Cd chemical fraction distribution by increases organic bound Cd. However, environmental behaviours of organic fertilizers in paddy are still lack exploration. Here, we critical reviewed previous publications and proposed a novel research concept to help us better understand it. Three potential impact pathways of utilization of organic fertilizers on the bioavailability of Cd are presented: (i) use of organic fertilizers changes soil physicochemical properties, which directly affects Cd bioavailability by changing chemical form of Cd(II); (ii) use of organic fertilizers increases soil nutrient content, which indirectly regulates Cd supply and bioaccumulation through ion adsorption and competition for ion-transport channels between nutrients and Cd; and (iii) use of organic fertilizers increases activity of microorganisms and efflux of rice root exudates, which indirectly affects Cd bioavailability of through complexation and sequestration of these organic materials with Cd. Meanwhile, dissolved organic matter (DOM) in the rhizosphere of rice is believed to be the key to revealing the effects of organic fertilizers on Cd. DOM is capable of adsorption and complexation-chelation reactions with Cd and the fractionation of Cd(II) is regulated by DOM. Molecular mass, chemical composition, major functional groups and reaction sequence of DOM determine the formation and solubilization of DOM-Cd complexes.

Reducing nitrogen fertilizer usage coupled with organic substitution improves soil quality and boosts tea yield and quality in tea plantations.

BACKGROUND: The utilization of chemical fertilizers is a key measure for maintaining tea yield and quality, but excessive use has negative environmental impacts. The substitution of chemical fertilizer with organic fertilizer has been promoted to sustain crop yield and soil quality. However, knowledge gaps regarding the effects of organic substitution on soil quality and tea yield in tea plantations still exist. RESULTS: A field experiment was conducted to investigate the influence of organic substitution treatments (i.e. 25% partial substitution: biogas slurry + green manure + formula fertilizer, BFG; sheep manure + formula fertilizer, OFF; 100% complete substitution: sheep manure + green manure, OG) on the soil quality, tea yield and quality, and nitrogen utilization efficiency in southwestern China. Results showed that all organic substitution treatments slightly increased soil pH, and significantly increased soil organic matter by 13.22-14.88% compared to conventional fertilization (CF). The BFG treatment was the most effective in enhancing the soil quality index, showing increases of 16.80%, 8.37% and 24.87% higher than the CF, OFF and OG treatments, respectively. Tea yield significantly increased under the BFG, OFF and OG treatments by 11.97%, 13.58% and 5.90% compared to CF, respectively. The BFG treatment increased the amino acid content by 7.78% and decreased the tea polyphenol/amino acid ratio by 6.87%. Additionally, the BFG, OFF and OG treatments greatly increased the nitrogen utilization efficiency of young sprouts by 70.71%, 82.54% and 34.28%, respectively. CONCLUSION: Overall, partial organic substitution could effectively improve soil quality while maintaining tea yield. © 2024 Society of Chemical Industry.

Enhancing soil health and nutrient availability for Carrizo citrange (X Citroncirus sp.) through bokashi and biochar amendments: An exploration into indoor sustainable soil ecosystem management.

This study investigated the efficacy of organic soil amendments: bokashi (Bok), biochar (BC), and their combination (Bok_BC) in promoting soil health, nutrient availability, and growth of Carrizo citrange (X Citroncirus sp. Rutaceae, Parentage Citrus sinensis × Poncirus trifoliata) under indoor greenhouse settings. Results indicate significant alterations in soil parameters like total carbon (C), total nitrogen (N), and C:N ratio due to Bok, BC, and Bok_BC treatments. BC treatments boosted total C, while Bok increased total N, compared to controls. A note-worthy 25 % average decrease in C:N ratio was observed with Bok and Bok_BC, nearing the optimal 24:1 C:N for microbial growth. This highlights the potential of waste by-products in balancing nutrient release to benefit soil health and plant development. Analysis of nitrite (NO2-), nitrate (NO3-), and ammonium (NH4-N) levels revealed a dynamic relationship between soil treatments and time. Bok and Bok_BC amendments combined with both fertilizer doses [700 and 1400 Electrical Conductivity, EC] showed an initial NH4-N spike (averaging 1513 and 1288 µg N/g dry, respectively), outperforming control soils (average 503 µg N/g dry). Other key elements like phosphorus, potassium, calcium, and chlorine also experienced initial surges in Bok and Bok_BC soils before declining, suggesting a gradual nutrient release. The concentration of potentially toxic elements remained mostly stable or inconclusive, warranting further exploration. Bok, BC, and Bok_BC treatments considerably influenced germination rate and plant growth. The germination rate averaged 24.2 %, 23 %, and 22.5 % for Bok, BC, and Bok_BC, compared to the 15.9 % control. Plant height increased with Bok, BC, and Bok_BC to 18.4 cm, 18.7 cm, and 16.4 cm, respectively, from the 14.8 cm control. The results remained consistent across fertilizer doses, emphasizing the soil amendments' role in bolstering soil and plant health. In summary, the research underscores the potential of carbon-based amendments like bokashi and biochar in enhancing soil health, reducing reliance on synthetic fertilizers, and fostering sustainable soil ecosystems. The insights are pivotal for advancing sustainable agriculture in indoor greenhouse settings for nursery plant production.

Overcoming China's animal waste disposal challenge brought by elevated levels of veterinary antimicrobial residues and antimicrobial resistance.

Direct application of animal waste on farmlands was banned in China recently, rendering organic fertilizer production a sound solution for disposing of animal manures and recycling their materials and nutrients. Due to the overuse of antimicrobials in livestock and poultry farms, manure-based organic fertilizers often contain elevated residues of antimicrobials and abundant antimicrobial resistance genes. Land application of such products has caused significant concerns on the environmental pollution of antimicrobials, and the transmission and development of antimicrobial resistance (AMR), which is a major global health challenge. China's recent attempt to restrict the contents of antimicrobial residues in organic fertilizers encountered strong resistance from the industry as it would hinder the utilization of animal manures as a raw material. Reducing and even eliminating the use of antimicrobials in animal farms is the ultimate solution to the challenge of manure disposal posed by the elevated levels of antimicrobial residues and AMR. Phasing out the non-therapeutic use of antimicrobials, developing substitutes of antimicrobials, enhancing animal welfare in farms, promoting diversification of animal farms, and developing antimicrobial removal and disinfection technologies for animal waste are recommended to improve the veterinary antimicrobial stewardship and manure management in China's animal agriculture. These concerted measures would enhance the sustainability of crop and animal farming systems in China and mitigate the impact of antimicrobials and AMR to agro-environmental quality and human health.

Regulating Leaf Photosynthesis and Soil Microorganisms through Controlled-Release Nitrogen Fertilizer Can Effectively Alleviate the Stress of Elevated Ambient Ozone on Winter Wheat.

The mitigation mechanisms of a kind of controlled-release nitrogen fertilizer (sulfur-coated controlled-release nitrogen fertilizer, SCNF) in response to O3 stress on a winter wheat (Triticum aestivum L.) variety (Nongmai-88) were studied in crop physiology and soil biology through the ozone-free-air controlled enrichment (O3-FACE) simulation platform and soil microbial metagenomics. The results showed that SCNF could not delay the O3-induced leaf senescence of winter wheat but could enhance the leaf size and photosynthetic function of flag leaves, increase the accumulation of nutrient elements, and lay the foundation for yield by regulating the release rate of nitrogen (N). By regulating the soil environment, SCNF could maintain the diversity and stability of soil bacterial and archaeal communities, but there was no obvious interaction with the soil fungal community. By alleviating the inhibition effects of O3 on N-cycling-related genes (ko00910) of soil microorganisms, SCNF improved the activities of related enzymes and might have great potential in improving soil N retention. The results demonstrated the ability of SCNF to improve leaf photosynthetic function and increase crop yield under O3-polluted conditions in the farmland ecosystem, which may become an effective nitrogen fertilizer management measure to cope with the elevated ambient O3 and achieve sustainable production.

Phosphorus-loaded coconut biochar: A novel strategy for cadmium remediation and soil fertility enhancement.

The management of cadmium (Cd) contamination in soils poses a significant environmental challenge. This study investigates the effectiveness of phosphorus (P)-loaded coconut biochar, synthesized at various pyrolysis temperatures (450°C, 500°C, 550°C, and 600°C), in immobilizing Cd and enhancing P availability in soil environments. The biochar underwent a series of treatments including activation and P enrichment, followed by incubation trials to evaluate its performance in Cd immobilization and P bioavailability enhancement across varying soil concentrations (0.5 %, 1.0 %, and 2.0 %) over time periods of 15, 30, and 45 days. Remediation progress was monitored using phytotoxicity assessments with radish (Raphanus sativus) root length as a bioindicator, supplemented by urease activity analyses. Notably, the activation process increased the P loading capacity of biochar produced at 450°C, 500°C, and 550°C by 54.6 %, 72.4 %, and 51.8 %, respectively, while reducing the P retention capacity of biochar prepared at 600°C by 31.0 %. The biochar activated at 550°C presented the highest efficiency in remediating Cd-contaminated soils. Key findings indicate that the enhanced specific surface area and oxygenated functional group content of the activated biochar facilitated Cd adsorption and P uptake. The P-loaded biochar exhibited a substantial adsorption capacity for Cd, particularly effective at lower concentrations, rendering it highly suitable for soil remediation purposes. Additionally, the study revealed that the application of biochar led to an increase in soil pH, resulting in precipitation of Cd as hydroxide species and formation of insoluble complexes with phosphate ions, thereby reducing its bioavailability. In summary, incorporating P-loaded biochar into soil significantly improved soil quality and enhanced Cd passivation in contaminated soils. The utilization of biochar produced at 550°C, which exhibited optimal performance, suggests a practical and sustainable approach for soil remediation. Future research endeavors should prioritize the refinement of the biochar production process to enhance cost-effectiveness while maintaining high P loading efficiency.

Analysis of Wall Thickness and Absorption Characteristics of Ammonium Nitrate(V) from Various Sources.

This study investigates the wall thickness and specific surface area (SBET) of ammonium nitrate(V) samples of varying provenance. The research focuses on both fertilizer-grade ammonium nitrate(V) and three porous prill samples obtained from different manufacturers. The samples were analyzed using tomography scanning and two distinct porosimetry methods. The wall thickness analysis revealed that fertilizer-grade ammonium nitrate(V) possesses thicker walls, ranging from 0.05 to 0.40 mm, compared to porous prill-type ammonium nitrate(V), which predominantly exhibited wall thicknesses between 0.05 and 0.025 mm, with occasional thicker regions up to 0.040 mm. These variations in wall thickness are likely attributable to differences in manufacturing processes and prilling conditions specific to the ammonium nitrate(V) porous prill-type samples. The specific surface area (SBET), derived from nitrogen adsorption measurements, indicated that the samples exhibited surface areas ranging from 0.011 to 0.466 m2·g, suggesting that these samples do not exhibit particularly high absorption capacities. However, the SBET values obtained from the mercury intrusion method suggested significantly higher absorption capacities, falling within the range of 4.87-18.29 m2·g. These findings suggest that mercury porosimetry may provide a more accurate assessment of the porosity and absorption potential of ammonium nitrate(V) samples.

Silicon Modifies Photosynthesis Efficiency and hsp Gene Expression in European Beech (Fagus sylvatica) Seedlings Exposed to Drought Stress.

Background: Climate change is leading to severe and long-term droughts in European forest ecosystems. can have profound effects on various physiological processes, including photosynthesis, gene expression patterns, and nutrient uptake at the developmental stage of young trees. Objectives: Our study aimed to test the hypothesis that the application of silica (SiO2) influences photosynthetic efficiency and gene expression in 1- to 2-year-old Fagus sylvatica (L.) seedlings. Additionally, we aimed to assess whether silicon application positively influences the structural properties of leaves and roots. To determine whether the plant physiological responses are genotype-specific, seedlings of four geographically different provenances were subjected to a one-year evaluation under greenhouse conditions. Methods: We used the Kruskal-Wallis test followed by Wilcoxon's test to evaluate the differences in silicon content and ANOVA followed by Tukey's test to evaluate the physiological responses of seedlings depending on treatment and provenance. Results: Our results showed a significantly higher Si content in the roots compared with the leaves, regardless of provenance and treatment. The most significant differences in photosynthetic performance were found in trees exposed to Si treatment, but the physiological responses were generally nuanced and provenance-dependent. Expression of hsp70 and hsp90 was also increased in leaf tissues of all provenances. These results provide practical insights that Si can improve the overall health and resilience of beech seedlings in nursery and forest ecosystems, with possible differences in the beneficial role of silicon application arising from the large differences in wild populations of forest tree species.