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In recent years, water environment quality of China has been constantly improved, but there is serious water pollution yet in some water sections of typical watersheds, particularly excessive pollutants such as nitrogen and phosphorus. On the other hand, aquatic plants have been applied to the remediation of contaminated waters, but the remediation performances of aquatic plants alone are not satisfactory. However, to set up a remediation system of aquatic plants combined with microorganism is a low-cost, environmentally friendly and sustainable technology. In this paper, the status quo of the application of aquatic plant-microorganisms in remediation of polluted waters in recent years was reviewed underlining the aquatic plant-microbe coupling configuration, mechanism of interaction and the mechanism of microbial augmentation of aquatic plants to remove water pollutants. In the end, the research orientation of the combined remediation technology was proposed. [ABSTRACT FROM AUTHOR]

Open vegetable fields in China are a major anthropogenic source of nitrous oxide (N2O) emissions due to excessive nitrogen (N) fertilization. A 4 yr lettuce experiment was conducted to determine the impacts of controlled-release fertilizers (CRFs) and nitrification inhibitors (NIs) on lettuce yield, N2O emissions and net economic benefits. Five treatments included (i) no N fertilizer (CK), (ii) conventional urea at 255 kg N ha–1 based on farmers' practice (FP), (iii) conventional urea at 204 kg N ha–1 (OPT), (iv) CRF at 204 kg N ha–1 (CU) and (v) CRF (204 kg N ha–1) added with NI (CUNI). No significant differences were found in the lettuce yields among different N fertilization treatments. Compared with FP, the cumulative N2O emissions were significantly decreased by 8.1%, 38.0% and 42.6% under OPT, CU and CUNI, respectively. Meanwhile, the net benefits of OPT, CU and CUNI were improved by USD 281, USD 871 and USD 1024 ha–1 compared to CN, respectively. This study recommends the combined application of CRF and NI at a reduced N rate as the optimal N fertilizer management for the sustainable production of vegetables in China with the lowest environmental risks and the greatest economic benefits. [ABSTRACT FROM AUTHOR]

The wide utilization of mulch-film brings great economic value but also causes "white pollution" in China. Based on the investigation and study on the distribution characteristics and influencing factors of soil plastic film residue in the typical maize planting area in Hebei and Inner Mongolia of China, the present situation of residual pollution in the system of maize planting field was accurately evaluated, and the scientific basis was provided for the proposal of prevention and control measures of residual pollution in this area. In this study, the amount and abundance of plastic film residues in different topsoil layers were investigated and analyzed in 21 farmlands with different years of plastic film mulching and no plastic film mulching fields as the control. The results showed that the amount of soil residual film was 4.04~314.73kg-hm-2 in topsoil soil of maize planting area, and 60.91% of the plots exceeded the national standard, therefore, the soil residual film pollution of maize cultivated layer in this area was serious. The amount and abundance of residual film in topsoil soil of maize planting area was increased with the increase of the years of film mulching. However, the amount and abundance of residual film was decreased gradually with the increase of soil layers. The amount and abundance of residual film distributed in the 0~10cm soil layer was significantly higher than that in the 10~20cm and 20~30cm soil layers. The residual film showed a downward trend to the deep soil with the increase of the plastic film mulching years. With increase of the plastic film mulching years, the abundance and ratio of residual film in small and medium size of soil layer (0~30cm) continuously decreased, and the small residual film < 4cm2 in 20~30cm soil showed an obvious increasing trend, which increased the difficulty of the recovery of residual film in long-term plastic film mulching farmland, and may have a long-term impact on the soil environment of topsoil. Therefore, appropriate measures should be taken to increase the recycling of plastic film and reduce the pollution of plastic film in this area and play a positive role in protecting the health of maize planting area in Hebei and Inner Mongolia. [ABSTRACT FROM AUTHOR]

Purpose: To characterize the genetic feature of the carbapenems resistant Acinetobacter johnsonii strain Acsw19 isolated from municipal sludge. This strain was found to carry two copies of blaNDM-1,cmlB1-like gene, and blaOXA-211-like gene along with other 8 antimicrobial resistance genes, 3 plasmids, 15 genomic islands and 8 prophages. Methods: A carbapenem-resistant Acinetobacter johnsonii strain Acsw19 isolated from municipal sludge was subjected to whole-genome sequencing (WGS) via the PacBio and Illumina MiSeq platforms. Thereafter, the characteristic was analyzed by a series of bioinformatics software. Results: The results showed that the genome of Acsw19 was consisted of a 3,433,749 bp circular chromosome and 3 circular plasmids, pAcsw19-1 (11,161 bp), pAcsw19-2 (351,885 bp) and pAcsw19-3 (38,391bp), respectively. Resistome analysis showed that Acsw19 carried 12 antimicrobial resistance genes, including 6 [cmlB1-like, blaNDM-1, blaOXA-58, aph (3ʹ)-VIa, msr(E) and mph(E)] in the plasmid pAcsw19-2 and 6 (blaOXA-211-like, blaNDM-1, aph(3")-Ib, aph(6)-Id, sul2, and floR) in the chromosome genome. Specifically, the cmlB1-like gene shared 86.33%, 71.7% and 71.9% similarities with the cmlB1, cmlA4 and cmlA8 gene, and the blaOXA-211-like gene shared 94.4%, 95.39% and 96.36% similarities with blaOXA-211, blaOXA-643 and blaOXA-652, at the nucleotide level, respectively. Phylogenetic analysis showed that the blaOXA-211-like gene and cmlB1-like gene had the closest evolutionary relationship with blaOXA-643 and cmlB1, respectively. These results indicated that the blaOXA-211-like and cmlB1-like genes identified in the current study should be the novel variant resistance genes. Conclusion: Carrying of two copies of blaNDM-1, cmlB1-like, blaOXA-211-like and along with other 8 antimicrobial resistance genes, 3 plasmids, 15 genomic islands and 8 prophages Acinetobacter johnsonii strain might increase the possibility of spreading of resistance genes. [ABSTRACT FROM AUTHOR]

Introduction: Improvement of root architecture is crucial to increasing nutrient acquisition., Methods: Two pot experiments were conducted to investigate the effects of different concentrations of urea ammonium nitrate solution (UAN) and ammonium polyphosphate (APP) on lettuce root architecture and the relationship between roots and nitrogen (N) and phosphorus (P) absorption., Results: The results showed that lettuce yield, quality, and root architecture were superior in the APP4 treatment compared to other P fertilizer treatments. The N480 treatment (480 mg N kg -1 UAN) significantly outperformed other N treatments in terms of root length, root surface area, and root volume. There were significant quantitative relationships between root architecture indices and crop uptake of N and P. The relationships between P uptake and root length and root surface area followed power functions. Crop N uptake was significantly linearly related to the length of fine roots with a diameter of <0.5 mm., Conclusion and Discussion: The length of fine roots played a more prominent role in promoting N absorption, while overall root size was more important for P absorption. APP has a threshold of 9.3 mg P kg -1 for stimulating the root system. Above this threshold, a rapid increase in root absorption of P. UAN can promote extensive growth of fine roots with a diameter less than 0.5 mm. Applying appropriate rates of APP and limiting UAN application to less than 400 mg N kg -1 can improve root architecture to enhance N and P absorption by lettuce. These results highlight a new possibility to improve nutrients use efficiency while maintaining high yields., Competing Interests: Author YL was employed by company Beijing Cuihu Agricultural Technology Co., Ltd.. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Li, Li, Yang, Lian, Wang and Zou.)

Pollutant gases and particulate matters (PM) from livestock facilities can affect the health of animals and farm workers and lead to great social environmental risks. This paper presents a comprehensive study on the characteristics of ammonia (NH 3 ), nitrogen oxides (NO x ), sulfur dioxide (SO 2 ) and PM (including PM 2.5 and PM 10 ) in a 100,000-bird manure-belt layer house in suburb Beijing for three typical seasons of summer, autumn and winter. Indoor air was sampled at an exhaust fan of the mechanically ventilated commercial house. The monitored indoor concentrations of NH 3 , NO x , SO 2 , PM 2.5 and PM 10 were 3.7-5.0 mg m -3 , 17-58 μg m -3 , 0-11 μg m -3 , 100-149 μg m -3 and 354-828 μg m -3 , respectively. The indoor NH 3 concentrations were largely influenced by the manure removal frequency. The NO x and SO 2 were mainly sourced from the ambient air, and the NO x was also partly sourced from manure decomposition in summer. The indoor PM 2.5 and PM 10 were largely sourced from the ambient air and the indoor manure, respectively. The abundant indoor NH 3 caused significantly higher NH 4 + concentration in the indoor PM 10 (7.98 ± 9.04 μg m -3 ) than that in the ambient PM 10 (3.48 ± 3.52 μg m -3 ). Secondary inorganic ions (SO 4 2- , NO 3 - and NH 4 + ) totally contributed 5.7% and 14.6% to the indoor and ambient PM 2.5 , respectively; they contributed 2.8% and 8.9% to the indoor and ambient PM 10 , respectively. Organic carbon was the main component of the PM and accounted for 26.6% and 41.5% of the indoor PM 2.5 and PM 10 , respectively. Heavy metal elements (Zn, Cu and Cr) were likely transported from feed to manure and finally accumulated in the PM. Given the high emission potential, the air pollutants from animal production suggested potential risks for human health., Competing Interests: Declaration of interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020. Published by Elsevier Ltd.)

Purpose: To characterize the genetic feature of the carbapenems resistant Acinetobacter johnsonii strain Acsw19 isolated from municipal sludge. This strain was found to carry two copies of bla NDM-1, cmlB1 -like gene, and bla OXA-211 -like gene along with other 8 antimicrobial resistance genes, 3 plasmids, 15 genomic islands and 8 prophages., Methods: A carbapenem-resistant Acinetobacter johnsonii strain Acsw19 isolated from municipal sludge was subjected to whole-genome sequencing (WGS) via the PacBio and Illumina MiSeq platforms. Thereafter, the characteristic was analyzed by a series of bioinformatics software., Results: The results showed that the genome of Acsw19 was consisted of a 3,433,749 bp circular chromosome and 3 circular plasmids, pAcsw19-1 (11,161 bp), pAcsw19-2 (351,885 bp) and pAcsw19-3 (38,391bp), respectively. Resistome analysis showed that Acsw19 carried 12 antimicrobial resistance genes, including 6 [ cmlB1 -like, bla NDM-1 , bla OXA-58 , aph ( 3' ) -VIa, msr(E) and mph(E) ] in the plasmid pAcsw19-2 and 6 ( bla OXA-211 -like, bla NDM-1 , aph(3")-Ib, aph(6)-Id, sul2 , and floR ) in the chromosome genome. Specifically, the cmlB1 -like gene shared 86.33%, 71.7% and 71.9% similarities with the cmlB1, cmlA4 and cmlA8 gene, and the bla OXA-211 -like gene shared 94.4%, 95.39% and 96.36% similarities with bla OXA-211 , bla OXA-643 and bla OXA-652 , at the nucleotide level, respectively. Phylogenetic analysis showed that the bla OXA-211 -like gene and cmlB1 -like gene had the closest evolutionary relationship with bla OXA-643 and cmlB1 , respectively. These results indicated that the bla OXA-211 -like and cmlB1 -like genes identified in the current study should be the novel variant resistance genes., Conclusion: Carrying of two copies of bla NDM-1 , cmlB1- like, bla OXA-211 -like and along with other 8 antimicrobial resistance genes, 3 plasmids, 15 genomic islands and 8 prophages Acinetobacter johnsonii strain might increase the possibility of spreading of resistance genes., Competing Interests: The authors declare no conflict of interest., (© 2020 Tang et al.)