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  • Concerning the entrance of oil into the Persian Gulf due to the presence of oil fields in this ecosystem, a wide investigation was carried out in 2017 to evaluate the hydrocarbons source identification and chemical fingerprinting. To this end, surface sediments were collected from the Persian Gulf. In the laboratory, compounds (n-alkanes, PAHs, hopane and sterane) were then extracted with a Soxhlet system and two steps of chromatographic columns and analyzed using a GC-MS instrument. The results showed that the concentrations of the n-alkanes and Σ30 PAHs increased with a reduction in distance from hot spots. This suggests that high concentrations of hydrocarbons in the locations near the hot spots might be due to oil leakage, transportation of and exploration for oil, pipeline fractures and industrial activities. A positive relation between total organic matter (TOM) and hydrocarbons was observed. A common petrogenic hydrocarbon source was strongly implied in most places by the presence of unresolved compounds resolved (UCM), lower molecular weight/higher molecular weight (LMW/HMW) and carbon preference index (CPI) ratios < 1. Typical profiles of petrogenic PAHs with predominant alkyl substituted naphthalene and phenanthrene, various PAH ratios and multivariate analysis showed that PAHs were mainly derived from petrogenic sources. Simultaneous use of n-alkanes and PAHs in source identification can be effective to precisely specify the hydrocarbon sources in complicated mixture ecosystems. Furthermore, using multivariate analysis and chemical fingerprinting of n-alkanes, PAHs, hopanes and sterane confirmed that Hendijan crude oil may be the source of the sediment pollution in the study area.

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  • Soil monitoring requires accurate and spatially explicit information on soil organic carbon (SOC) trends and changes over time. Spatiotemporal SOC models based on Earth Observation (EO) satellite data can support large-scale SOC monitoring but often lack sufficient temporal validation based on long-term soil data. In this study, we used repeated SOC samples from 1986 to 2022 and a time series of multispectral bare soil observations (Landsat and Sentinel-2) to model high-resolution cropland SOC trends for almost four decades. An in-depth validation of the temporal model uncertainty and accuracy of the derived SOC trends was conducted based on a network of 100 long-term monitoring sites that were continuously resampled every 5 years. While the general SOC prediction accuracy was high (R = 0.61; RMSE = 5.6 g kg), the direct validation of the derived SOC trends revealed a significantly greater uncertainty (R = 0.16; p < 0.0001), even though predicted and measured values showed similar distributions. Classifying the results into declining and increasing SOC trends, we found that 95% of all sites were either correctly identified or predicted as stable (p < 0.001), highlighting the potential of our findings. Increased accuracies for SOC trends were found in soils with higher SOC contents (R = 0.4) and sites with reduced tillage (R = 0.26). Based on the signal-to-noise ratio and temporal model uncertainty, we were able to show that the necessary time frame to detect SOC trends strongly depends on the absolute SOC changes present in the soils. Our findings highlight the potential to generate significant cropland SOC trend maps based on EO data and underline the necessity for direct validation with repeated soil samples and long-term SOC measurements. This study marks an important step toward the usability and integration of EO-based SOC maps for large-scale soil carbon monitoring.

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  • Water scarcity is a global concern that needs addressing through alternative sources. One of the approaches is the use of reclaimed water for irrigation. However, the presence of halogenated compounds and heavy metals in reclaimed water poses significant food safety threats. Therefore, a comprehensive characterization of these contaminants using a reliable method is essential. This study presents an innovative analytical technique that combines electrospray ionization (ESI) with microwave plasma ionization mass spectrometry (MPIMS), enabling the simultaneous detection of organic compounds and heavy metals. The plasma ionization process in metals exhibits novel features, unlike traditional methods, making it suitable for organic and metallic detection in complex matrices. This technique achieved a recovery rate of 78.5-123% and 79.93-119.50% for halogenated compounds and heavy metals, respectively. The limits of detection and quantification ranged from 1.5 ng mL to 3.5 ng mL and 4.5 ng mL to 12.75 ng mL, respectively. Analysis of reclaimed water from three irrigation systems revealed concentrations of halogenated compounds and heavy metals below allowable levels set by national agencies, indicating manageable pollution risks. H-compounds, such as diuron and linuron, were prevalent in all samples, while zinc and lead showed higher levels in flood and sub-irrigation systems. Compared to traditional methods, ESI-MPIMS performs well and demonstrates high efficiency, good quantification, and high sensitivity in the analysis of real samples. This study shows that ESI-MPIMS is promising for on-site analysis of organic compounds and heavy metals in complex matrices and is suitable for water quality control and environmental quality assessment for pollutant screening.

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  • Current agricultural practices prioritize intensive food production, often at the expense of environmental sustainability. This approach results in greenhouse gas emissions and groundwater pollution due to over-fertilization. In contrast, organic agriculture promotes a more efficient use of non-renewable energy, improves soil quality, and reduces ecological damage. However, the effects of mulching and organic manure on maize yield, water use efficiency (WUE), and nitrogen use efficiency (NUE) in China's Loess Plateau have not been sufficiently researched. In 2017 and 2018, an experiment utilizing a randomized complete block design with two factors (two mulching levels × three organic nitrogen application rates) was conducted. The water content of the upper soil layer was found to be 12.6% to 19.4% higher than that of the subsoil layer. Across all soil depths and years, the soil nitrate-N content in mulched treatments was 10% to 31.8% greater than in non-mulched treatments with varying organic nitrogen rates. Additionally, mulching resulted in an increase in grain yield of 9.4% in 2017 and 8.9% in 2018 compared to non-mulched treatments. A significant interaction was observed between mulching and organic nitrogen application rate concerning WUE, alongside a negative correlation between WUE and NUE. These findings suggest that the application of 270 kg N ha of sheep manure in conjunction with mulching is a highly recommended practice for the Loess Plateau, thereby supporting sustainable agricultural strategies.

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  • Intelligent controlled-release nanopesticides have been a crucial tactic in advanced precision agriculture during the past few years, which can improve pesticide utilization and reduce environmental pollution. Herein, a novel hydroxypropyl methylcellulose-based nanopesticide carrier (PCH) with pH-/enzyme-/near-infrared multiple responses was constructed by the initial cross-linking with dimethyl diallyl ammonium chloride and the subsequent copper ion chelation and polydopamine coating. Avermectin (Av) was further loaded to create the intelligent pesticide release system (APCH) by antisolvent precipitation. The release of APCH increases under near-infrared light (NIR) conditions, with an accumulative release that is 3.26 times higher than that without NIR. The contact angles of APCH on cabbage leaves are 33 and 29% lower than those of water and technical Av (Av-tech), respectively, verifying that APCH has a good wettability property. Simultaneously, APCH displays better insecticidal activity than Av formulations because of its outstanding ultraviolet (UV) light stability of Av. The degradation rate of Av in APCH is less than 2% in 50 h under UV light, which is considerably lower than that of Av-tech (∼60%). The biosafety assessments manifest that the PCH carrier has remarkable biological safety on the growth of nontarget organisms in a certain range. Overall, the APCH system is bio-friendly with multiple-response release behaviors, excellent UV light stability, and foliar deposition performance, which can offer a new strategy for sustainable agricultural development.

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  • Food production faces important challenges such as water scarcity and the overall need of novel sustainable strategies. This study assesses the effect of the biostimulant produced through solid-state fermentation (SSF) of green waste (wood chips and grass residues) inoculated with Trichoderma harzianum with and without L-tryptophan as a precursor for indole-3-acetic acid (IAA) production, a well-known plant hormone. The fermented solid demonstrated significant positive effects on the growth of lettuce (Lactuca sativa L.) under different irrigation conditions. Substantial enhancements were observed in growth parameters such as fresh weight, plant height, leaf area and leaf quantity, along with chemical parameters including total phenol content, chlorophylls, carotenoids, and antioxidant activity (DPPH). The results also showed a positive impact on the nutritional quality of lettuce, particularly under normal irrigation conditions. In conclusion, this study highlights the biostimulant potential to improve the yield and nutritional quality of lettuce crops by reusing plant residues. Additionally, it poses the relevance of applying circular economy principles in sustainable agriculture and organic waste management.

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  • The purpose of this study is to clarify the roles of thermophilic bacteria in humification during hyperthermophilic composting (HTC) of organic wastes mainly composed of mushroom residue. Results showed that HTC with a long hyperthermophilic (>80°C) period lasting for 18 days produced 83 mg/g of humus in compost on day 27, significantly higher than that of thermophilic composting (TC, 9.7 mg/g). Machine learning models identified that the dominant thermophiles belonging to Bacillaceae, Sporolactobacillaceae, Thermaerobacteraceae, Paenibacillaceae families and the unique thermophiles (Thermus and Calditerricola) in HTC played important roles in accumulating stubborn and soluble humus including humic acid and fulvic acid. Hyperthermophilic fermentation not only recruited and enriched these thermophilic bacteria to rapidly degrade organic matter into bioavailable nutrients, but also upregulated the metabolic pathways relevant to the generation and oxidation of precursors including amino acids that would be polymerized into humus, thus efficiently converting organic waste into humus-rich compost.

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  • High greenhouse gas emissions and soil deterioration are caused by the overuse of chemical fertilizers. To improve soil quality and crop productivity, it is necessary to utilize fewer chemical fertilizers to achieve sustainable agriculture. Organic substitution is a scientific fertilization strategy that will benefit future agricultural productivity development, little is known about how it affects the heavy metal content and trace gas emissions in rice grains. A field experiment using straw return to the field (SRF), organic fertilizer application (OFA), and their combination (SRF/OFA) fertilization strategies. The results demonstrated that SRF, OFA, and SRF/OFA increased the yield by 19.40%, 22.39%, and 28.36% than the natural growth control group (NG). The OFA has the highest STN stock and SRF/OFA has the highest STN sequestration rate, while SRF achieved the highest SOC stock and sequestration rate. The OFA reduced CO, CH, and NO emissions by 17.73%, 71.87%, and 86.06%, resulting in a minimum global warming potential and greenhouse gas intensity yield among these strategies. Cumulative seasonal CO and CH emissions were negatively correlated with soil paddy soil C/N and C/P (P < 0.05). Moreover, Cu, Cd, and Pb contents in grain were reduced by 66.18%-70.31%, 35.45%-40.91%, and 76.62%-77.92%, respectively. The health risk evaluation revealed that all metals had a target hazard quotient of < 1, except for NG. The hazard index (0.42-0.53), which measures the additive effects of contaminants, exceeded the threshold. The implementation of the organic alternative strategy can reduce the trend of increasing surface pollution, slow down the excessive utilization intensity of agricultural resources, and encourage the development of a greener, more sustainable agricultural way.

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  • Setaria pumila (SP) and latuca sativa are the prominent teff (Eragrostis tef) weeds negatively impacting yield. The allelopathic (weed-suppressing) effects of ten teff varieties were examined for plant growth inhibitory effects, as well as for antagonism against certain major plant infections caused by bacteria and their subsequent antioxidant properties. The in vitro germination and antimicrobial assays were carried out in controlled laboratory settings. The teff cultivar DZ-Cr-387 suppressed weed germination and had substantial allelopathic potential. Both teff shoot and root extracts were noted to have an allelopathic influence on experimental seed germination in comparison to the control. Observations were made on the germination percentage, rate of germination, and germination duration. Additionally, extracts from teff shoots and roots showed significant free radical scavenging activity. Reactive oxygen species, or ROS, have been demonstrated to operate as both signalling compounds and harmful molecules that can oxidatively affect plant tissues throughout all stages of their lifecycle. The highest level of inhibition was reported in DZ-Cr-387 and DZ-01-1681, with a free radical scavenging potential of 85 percentage. The allelopathic teff varieties were also clustered together, indicating that these teff varieties have the potential for allelopathic and anti-microbial capabilities. These allelopathic chemicals can be employed as part of eco-friendly weed management strategies, to generate antimicrobial compositions to combat plant diseases for sustainable agriculture and for use in organic farming. Utilizing these teff varieties will benefit organic farmers by lowering their reliance on chemical inputs in traditional farming systems.

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  • A press-actuated slidable microfluidic colorimetric biosensor was designed for rapid, sensitive and multi-channel detection of Salmonella. The nickel mesh sheet (NMS) modified with capture antibodies was employed for capturing target bacteria, and metal organic frameworks decorated with palladium (Pd) and platinum (Pt) nanoparticles (MIL-88@Pd/Pt NPs) modified with detection antibodies were used for amplifying colorimetric signals. The capture efficiency of the immune NMS reached 83 %, and the detection limit of this colorimetric biosensor was 35 CFU/mL in 20 min. The average recoveries for Salmonella in spiked chicken meats ranged from 92.2 % to 102.5 % with a variation from 3.7 % to 7.2 %. The press-actuated slidable microfluidic chip was elaboratively developed with multiple functions, including mixing, separation, washing, catalysis and detection.

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