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Valorization of invasive plant biomass through pyrolysis into biochar offers opportunities for waste management and resource recovery. However, the release of biochar-derived dissolved organic matter (BDOM), which influences carbon dynamics and pollutant mobility, remains poorly understood. This study investigated BDOM from Japanese knotweed biochar (500 degrees C) using seven extraction methods, covering mild aqueous conditions (water and CaCl2), salt effects (NaCl), standardized acidic leaching tests (the synthetic precipitation leaching procedure, SPLP, and the toxicity characteristic leaching procedure, TCLP), and strong chemical extraction conditions (HCl and NaOH). NaOH and HCl maximized dissolved organic carbon (DOC) release (75-183 mg L-& sup1;) while the resulting BDOM exhibited low aromaticity (SUVA(254): 1.8-5.3) and relatively lower molecular weight (E-2/E-3 > 0.5). In contrast, mild extraction (water and CaCl2) released less DOC (5-15 mg L-& sup1;) but preserved high-aromaticity components with larger molecular weights. Fluorescence analysis identified four distinct BDOM components: (1) a terrestrial humic-like substance (C4) preferentially extracted by water, (2) a fulvic-like component (C2) dominant in NaCl and SPLP extracts, (3) a protein-like component (C1) most abundant in NaCl extract, and (4) a transitional component (C3) that decreased under acidic conditions. The results demonstrate that extraction method influences BDOM quantity, optical characteristics, and compositional features, providing a useful framework for understanding BDOM behavior and informing the environmental management of invasive plant.

In agrivoltaic systems combining agriculture and solar photovoltaics (PVs), conventional silicon solar panels frequently fail to meet the light requirements of most shade-intolerant plants due to the severe shading they cause. However, plants require a specific spectrum of solar irradiance to thrive. In certain situations, a whole spectrum may even be harmful to plant growth. Wavelength-selective solar photovoltaic (WSPV) technologies can be a promising solution as it considers the absorption profiles of plants and enables the transmission of light at wavelengths that are beneficial for photosynthesis. This study summarises a 2-year experiment on the growth of broccoli (Brassica oleracea L. var. italica, cv. Marathon) under semi-transparent (ST), magenta-coloured cadmium telluride (CdTe) PV modules with varying transparency levels and system heights. Transparency is achieved by spatially segmenting opaque CdTe cells and adjusting cell density. Wavelength-selectivity is achieved through a polyvinyl butyral coloured interlayer encapsulant. The magenta colour is chosen to better match chlorophyll absorption peaks. It increases transmittance in the blue and red light regions and reduces it in the green region, without eliminating it, which is still necessary for certain plant processes. Experiments were conducted in Kärrbo Prästgård, Sweden (59.55°N, 16.76°E), during the growing seasons from May to October in 2023 and 2024. Data collected included several crop physiological parameters, microclimatic conditions, and energy conversion by the PV panels. Preliminary analysis shows that in 2023, crop yields (fresh head biomass) under ST-panels were significantly lower than the control plot due to insufficient light caused by the system design. In 2024, elevating the mounting structures increased light availability, resulting in statistically non-significant yield differences compared to the control plot. Further analysis of the collected data will explore the potential of this type of PV technology for power conversion and broccoli growth and quality in this high-latitude region, aiming to inspiring comparative studies in other parts of the world.

With carbon dioxide (CO2) levels continuing to rise in the coming decades and threatening agro-ecosystems worldwide, it is crucial to understand the impact of elevated CO2 on global food production and security. Elevated CO2 levels have been found to reduce micronutrients such as Zinc (Zn) and Iron (Fe) in staple crops, potentially exacerbating the already existing global micronutrient deficiency issue. However, as vegetables serve as another key source of micronutrients, it remains uncertain to what extent this negative effect on micronutrient levels also applies to them. To address this, we investigated the effects of elevated CO2 on Zn and Fe in vegetables using a meta-analysis. As expected, we found a significant increase (27%, 95% CI: 14-41%) in vegetable biomass production under elevated CO2 levels. Elevated CO2 (i) significantly reduced overall Zn concentration in vegetables by 8.9% (95% CI: 4-14%), while this effect was pronounced only in fruit vegetables (11%), but not in leafy and stem vegetables; (ii) consistently exhibited minimal effects on Fe concentration in vegetables. In the context of climate change with rising CO2 levels, these findings suggest that elevated CO2 could potentially exacerbate Zn deficiencies through vegetable consumption, albeit with enhanced vegetable yields. Furthermore, as the global population increasingly adopts vegetarian diets in the future, these results underscore the need for mitigation strategies to address potential future micronutrient deficiencies.

Increasing attention has been given to the role of reductive soil disinfestation (RSD) on antibiotic resistance genes (ARGs) in soil. The selection of organic materials in RSD is crucial to the effectiveness of the RSD method. However, the effects of distinct organic materials on ARGs remains unclear. In this study, we selected straw and rapeseed meal as the organic materials in RSD and explored their effects on ARGs. The results showed that using straw significantly reduced the abundance of ARGs, high-risk ARGs, and mobile genetic elements (MGEs) by 31.5 %–65.8 %, while using rapeseed meal led to ARGs enrichment. Structural equation modeling (SEM) analysis identified MGEs and microbial communities as the primary drivers of ARGS changes under different organic materials. The abundance of MGEs was effectively controlled in straw treatments, reducing the potential for horizontal gene transfer of ARGs. Bacterial diversity was significantly lower in the straw treatments compared to the rapeseed meal treatments, potentially leading to a reduced abundance of ARGs host bacteria. Network co-occurrence analysis further revealed that Symbiobacteraceae and Bacillus were potential bacterial hosts of ARGs. In straw treatments, these genera’ abundance decreased by 12 %–100 % compared to the control (CK) and rapeseed meal groups, further inhibiting the spread of ARGs. These findings demonstrate that RSD with straw as the organic material is more effective in mitigating ARGs compared to rapeseed meal, providing insights into controlling soil antibiotic resistance risks and utilizing agricultural waste resources.

Selenium (Se) is an essential trace element for humans and animals, and adequate Se nutrition heavily relies on sufficient Se in plants. Plants acquire Se predominantly through root uptake from soil, however, large areas in the world are deficient in Se. To increase the Se absorption and accumulation in plants, selenate and selenite have traditionally been applied. Nevertheless, these chemicals are highly soluble and prone to loss via runoff and leaching, posing risks of secondary soil and water contamination and exhibiting low utilization efficiency by plants. Various novel Se biofortification techniques are emerging to address these challenges. This study summarized the progress in the researches of current Se biofortification technologies within soil-plant systems. Distinguished by the approaches to enhancing Se uptake and accumulation in plants, novel Se biofortification technologies encompass several strategies. These include utilizing genetic engineering to enhance plants' capacity for Se uptake, utilization, and accumulation; employing nanotechnology to produce highly efficient nano-selenium formulations (fertilizers); leveraging functional microorganisms to activate Se in soil, thereby synergizing Se uptake; and producing organic fertilizers with high Se content from the by-products of industrial and agricultural activities in Se-rich regions. Genetic engineering techniques primarily aim to modify the inherent genetic traits of plants, enabling them to possess greater Se absorption and accumulation capabilities and to stably transmit Se-enriched traits to subsequent generations. Nano-selenium biofortification mainly harnesses nanotechnology to improve Se bioavailability and reduce its toxicity, featuring a relatively short synthesis cycle and a broad safe dosage range, thus holding the potential to replace traditional inorganic Se fertilizers. Microbial-assisted biofortification exploits microorganisms’ ability to transform Se, increasing the available Se forms in the soil-plant system and facilitating Se uptake by plants, thereby elevating Se content. The slow-release Se fertilizers derived from Se-rich organic materials fully utilize Se-rich plants and their by-products grown in Se-rich or Se-contaminated areas to produce slow-release Se fertilizers, which not only enhance crop Se content but also improve resource recycling and utilization efficiency. To expedite the practical application of these novel Se-enrichment technologies, future research should focus on the following areas: 1) investigating the genetic mechanisms underlying Se uptake and transformation in crops and breeding Se-rich crop varieties; 2) optimizing the preparation methods of nano-selenium biofertilizers to enhance their stability and bioactivity; 3) screening and identifying microorganisms capable of Se transformation and exploring their transformation mechanisms; 4) developing and applying Se-rich slow-release organic fertilizers, as well as determining how to regulate Se release rates to align with the demands of plant growth cycles. © 2025, Chinese Academy of Agriculture Sciences,Editorial Department of Journal of Plant Nutrition and Fertilizer. All rights reserved.

Soil erosion is the first threat to soil functions. Reducing the soil aggregate breakdown strength is a key step to improve the soil's ability to resist rainfall splash erosion. Soil internal forces have been found to be the initial and important forces driving aggregate turnover. The application of exogenous organic materials can effectively improve soil aggregate stability and the resistance to rainfall erosion of agricultural soils. However, from the perspective of soil internal forces, information about the reduction effects of the exogenous organic materials application on soil aggregate breakdown is scarce, especially in comparing the effects of different materials. In this study, weathered coal and biochar were individually applied to loamy clay soil at rates of 0 %, 1 %, 2 %, and 3 % (w/w). Soil internal forces, aggregate breakdown strength, and splash erosion rate of different amended soils were then examined after four years. The results showed that compared with unamended soils (0 %), both weathered coal and biochar applications clearly increased the van der Waals attractive pressure and thus decreased the positive net pressure between soil particles. Additionally, these materials reduced soil aggregate breakdown strength and splash erosion rate. The application effects of the two materials were increased with their application rates. Under a lower electrolyte concentration in soil solution (0.0001 mol L−1), the aggregate breakdown strength in the soils amended with weathered coal was lower than that with biochar by 9.6 %, 23.2 %, and 17.7 % (when the diameter of broken aggregate was < 10 μm) and by 10.3 %, 20.8 %, and 17.5 % (when the diameter of broken aggregate was < 20 μm) at the 1 %, 2 %, and 3 % application rates, respectively (P < 0.05). Additionally, soils amended with weathered coal exhibited lower splash erosion rates compared to those amended with biochar, particularly at the higher application rate of 3 %. From the viewpoint of soil internal forces, weathered coal appears to be a suitable exogenous organic material for improving soil aggregate stability and anti-erosion ability during rainfall events. Our findings provide valuable insights into utilizing exogenous materials to improve soil resistance to rainfall splash erosion, assisting agricultural soil management in areas frequently affected by rainfall erosion.

Due to the natural biochar aging, the improvement of soil quality and immobilization of soil pollutants achieved by biochar may change; understanding the dynamic evolution of the in situ performance of biochar in these roles is essential to discuss the long-term sustainability of biochar remediation. Therefore, in this study, combined biochar from co-pyrolysis of pig manure and invasive Japanese knotweed – P1J1, as well as pure pig manure – PM – and pure Japanese knotweed – JK – derived biochar were applied to investigate their remediation performance in a high As- and Pb-polluted soil with prolonged incubation periods (up to 360 days). Biochar application, especially P1J1 and PM, initially promoted soil pH, dissolved organic carbon, and EC, but the improvements were not constant through time. The JK-treated soil exhibited the highest increase of soil organic matter (OM), followed by P1J1 and then PM, and OM did not change with aging. Biochar, especially P1J1, was a comprehensive nutrient source of Ca, K, Mg, and P to improve soil fertility. However, while soluble cationic Ca, K, and Mg increased with time, anionic P decreased over time, indicating that continuous P availability might not be guaranteed with the aging process. The total microorganism content declined with time; adding biochars slowed down this tendency, which was more remarkable at the later incubation stage. Biochar significantly impeded soil Pb mobility but mobilized soil As, especially in PM- and P1J1-treated soils. However, mobilized As gradually re-fixed in the long run; meanwhile, the excellent Pb immobilization achieved by biochars was slightly reduced with time. The findings of this study offer fresh insights into the alterations in metal(loid)s mobility over an extended duration, suggesting that the potential mobilization risk of As is reduced while Pb mobility slightly increases over time.

The atmospheric carbon dioxide (CO2) concentration has been progressively increasing since the onset of the Industrial Revolution and has already reached at around 420 μmol mol⁻¹ nowadays. It is well recognized that elevated CO2 concentration stimulates the yield for C3 crops, but it also simultaneously changes the essential nutrients. However, compared with the main crops, far less attention has been devoted to the effects of elevated CO2 concentration on vegetable growth and quality. Vegetables are highly recommended in daily diets due to their diverse range of beneficial compounds, such as vitamins, antioxidants, minerals, and dietary fiber.  In controlled greenhouse vegetable cultivation, elevated CO2 has been widely adopted as an agricultural practice for enhancing plant growth. Thus, understanding both vegetable growth and nutrient status is crucial to assess the potential impacts of elevated CO2 on future food security in both natural and controlled environments. However, much more attention has been paid to biomass enhancement, and elevated CO2 effects on nutrient quality are less recognized. Among the nutrients, Zinc (Zn) and Iron (Fe) are essential elements in humans. Previous studies have demonstrated a decreasing trend of Zn and Fe in main crops such as wheat and rice with increased CO2, while less is known about whether this alleviation effect on Zn and Fe can apply to vegetables. Therefore, a meta-analysis was conducted in this study to evaluate the influence of elevated CO2 concentration in the atmosphere on vegetable Fe and Zn status, and quantify the potential impact of future climate on nutrition security.

Pepper is a key agricultural crop susceptible to accumulating heavy metals like cadmium (Cd) and barium (Ba), posing significant health risks. To address these issues, this study investigated the effects of foliar applications of fulvic acid (FA), Zn-fulvic acid (Zn-FA), and Fe-fulvic acid (Fe-FA) on Ba and Cd uptake in pepper tissues, as well as their impact on nutritional quality, biomass, and leaf enzyme activity. Results indicated that Fe-FA application significantly reduced Cd and Ba in pepper fruit by 25 % and 93 %, respectively. Additionally, Fe-FA enhanced pepper growth, increasing vitamin C and phenolic compounds by 136 % and 13 %, respectively. Metabolomics analysis revealed that Fe-FA application up-regulated 857 metabolites and down-regulated 1045 metabolites. Furthermore, Fe-FA primarily influenced amino acid, carbohydrate, and lipid metabolism, promoting pepper growth. These findings suggest that Fe-FA foliar application offers a promising strategy for reducing Ba and Cd accumulation in pepper fruits while enhancing its nutritional quality.

Phytostabilization of metal-contaminated soils can be enabled or improved by biochar application. However, biochar-aided effects vary on biochar types, and little attention has been paid to plant management (time and cutting) to enhance phytostabilization efficiency in synergy with biochar. Therefore, biochars derived from pig manure (PM), Japanese knotweed (JK), and a mixture of both (P1J1) were applied to Pb and As mining soil with ryegrass cultivation to assess the biochar-induced effects on plant growth, dissolved organic matter (DOM), As and Pb mobility, and bioaccumulation within a phytostabilization strategy. Additional treatments involving the combined biochar (P1J1) and ryegrass were conducted to explore the influence of sequential cutting and growing time on facilitating phytostabilization efficacy. Biochar applications promoted plant growth, progressively increasing over time, but were not enhanced by cutting. Short and long-wavelength humic-like DOM substances identified in the soil pore water after biochar application varied depending on the biochar types used, providing evidence for the correlation among DOM changes, biochar origin, and metal immobilization. Biochar-treated soils exhibited reduced Pb availability and enhanced As mobility, with P1J1 stabilizing Pb significantly similar to PM while causing less As mobilization as JK did. The mobilized As did not result in increased plant As uptake; instead, all biochar-added plants showed a significant decrease in As and Pb concentrations compared to those without biochar. Soil available As decreased while available Pb increased with time, and cutting did not influence soil As behavior but did reduce soil Pb release. Nevertheless, plant As and Pb concentrations decreased over time, whereas those in multiple-cut plants were generally higher than those without cuts. Biochar, especially P1J1, along with growth time, holds promise in promoting plant biomass, reducing plant Pb and As concentrations, and minimizing the migration of Pb–As within the soil.