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C-offset and crop energy efficiency increase due industrial poultry waste use in long-term no-till soil minimizing environmental pollution Texto completo
2021
Romaniw, Jucimare | de Moraes Sá, João Carlos | Lal, R. | de Oliveira Ferreira, Ademir | Inagaki, Thiago Massao | Briedis, Clever | Gonçalves, Daniel Ruiz Potma | Canalli, Lutécia Beatriz | Padilha, Alessandra | Bressan, Pamela Thaísa
Brazil is one of the major global poultry producers, and the organic waste generated by the chicken slaughterhouses can potentially be used as a biofertilizer in agriculture. This study was designed to test the hypothesis that continuous use of biofertilizer to the crops, substituting the use of mineral fertilizer promote C-offset for the soil and generate crop energy efficiency for the production system. Thus, the objectives of this study were to evaluate the effects of biofertilizer use alone or in combination with mineral fertilizer on soil organic carbon (SOC) stock, carbon dioxide (CO₂) mitigation, C-offset, crop energy efficiency and productivity, and alleviation of environmental pollution. The experiment was established in southern Brazil on a soil under 15 years of continuous no-till (NT). Experimental treatments were as follows: i) Control with no fertilizer application, ii) 100% use of industrial mineral fertilizer (Min-F); iii) 100% use of organic waste originated from poultry slaughterhouses and hereinafter designated biofertilizer (Bio-F), and iv) Mixed fertilizer equivalent to the use of 50% mineral fertilizer + 50% of biofertilizer (Mix-F). Effects of experimental treatments were assessed for the crop sequence based on bean (Phaseolus vulgaris), soybean (Glycine max) and corn (Zea mays) in the summer and wheat (Triticum aestivum) and black oat (Avena strigosaSchreb) in the winter composing two crops per year, as follow: bean/wheat-soybean/black oat-corn/wheat-soybean/black oat-corn/wheat-bean. The continuous use of Bio-F treatment significantly increased the index of crop energy efficiency. It was higher than that of control, and increased it by 25.4 Mg CO₂eq ha⁻¹ over that of Min-F treatment because of higher inputs of crop biomass-C into the system. Further, continuous use of Bio-F resulted in a significantly higher CO₂eq stock and offset than those for Min-F treatment. A positive relationship between the C-offset and the crop energy efficiency (R² = 0.71, p < 0.001) indicated that the increase of C-offset was associated with the increase of energy balance and the amount of SOC sequestered. The higher energy efficiency and C-offset by application of Bio-F indicated that the practice of crop bio fertilization with poultry slaughterhouse waste is a viable alternative for recycling and minimizing the environmental impacts.
Mostrar más [+] Menos [-]Occurrence and distribution of antimicrobial resistance genes in the soil of an industrial park in China: A metagenomics survey Texto completo
2021
Zheng, Beiwen | Liu, Wenhong | Xu, Hao | Li, Junfeng | Jiang, Xiawei
As zoned areas of industries, industrial parks have great impacts on the environment. Several studies have demonstrated that chemical compounds and heavy metals released from industrial parks can contaminate soil, water, and air. However, as an emerging pollutant, antimicrobial resistance genes (ARGs) in industrial parks have not yet been investigated. Here, we collected soil samples from 35 sites in an industrial park in China and applied a metagenomics strategy to profile the ARGs and virulence factors (VFs). We further compared the relative abundance of ARGs between the sites (TZ_31–35) located in a beta-lactam antimicrobial-producing factory and other sites (TZ_1–30) in this industrial park. Metagenomic sequencing and assembly generated 14, 383, 065 contigs and 17, 631, 051 open reading frames (ORFs). Taxonomy annotation revealed Proteobacteria and Actinobacteria as the most abundant phylum and class, respectively. The 32 pathogenic bacterial genera listed in the virulence factor database (VFDB) were all identified from the soil metagenomes in this industrial park. In total, 685,354 ARGs (3.89% of the ORFs) and 272,694 virulence factors (VFs) (1.55% of the ORFs) were annotated. These ARGs exhibited resistance to several critically important antimicrobials, such as rifampins, fluroquinolones, and beta-lactams. In addition, no significant difference in the relative abundance of ARGs was observed between sites TZ_31–35 and TZ_1–30, indicating that ARGs have already disseminated widely in this industrial park. The present study gave us a better understanding of the whole picture of the resistome and virulome in the soil of the industrial park and suggested that we should treat the industrial park as a whole in the surveillance and maintenance of ARGs.
Mostrar más [+] Menos [-]Effects of long-standing exposure to heavy-duty diesel vehicle traffic on respiratory symptoms and airway inflammation in older adults Texto completo
2021
Carvalho-Oliveira, Regiani | Amato-Lourenço, Luís F. | Almeida, Pâmela S. | Garcia, Bianca B.M. | Vieira, William K.M. | Santana, Ariane | Motta Godinho-Netto, Martha Cristina | Carretero, Maria E. | Nascimento Saldiva, Paulo H. | Mauad, Thais
In the present study, we evaluated the effects of chronic exposure to traffic from a heavy-duty diesel-fueled vehicle area on respiratory symptoms and airway inflammation in a nonsmoking adult and elderly population. Respiratory symptoms were evaluated by the ISAAC questionnaire (International Study of Asthma and Allergies questionnaire), and airway inflammation was assessed by fractional exhaled nitric oxide (FeNO). Forty volunteers were selected from the 112 volunteers who completed the ISAAC questionnaire for the measurement of FeNO. The FeNO population comprised seven men (six aged ≥ 64 years old, four aged ≥ 75 years old) and 32 women (27 aged ≥ 64 years old, nine aged ≥ 75 years old). FeNO levels were tracked for six months, from November 2014 to June 2015. Results: Twenty-four percent of the volunteers reported having had wheezing in the chest in the last 12 months. However, only 2.7% of the volunteers reported doctor-diagnosed asthma. There was a positive association between FeNO and pollutants in most of the study months. An increase of 1 μg m⁻³ in NO₂ was associated with a mean increase of 1.08 ppb in FeNO, and an increase of 1 μg m₋₃ in O₃ was associated with a mean increase of 1.06 ppb in FeNO. The relative risk for NO₂ ranged from 1.009 to 1.32 and that for O₃ ranged from 1.014 to 1.020. Conclusion: The frequency of respiratory symptoms was much higher than the previously described levels of 6% in the Brazilian adult population. In summary, a high frequency of respiratory symptoms and high levels of FeNO were described in an underdiagnosed adult population living very close to a heavy-duty diesel-traffic area. Older elderly adults presented greater susceptibility to airway inflammation than younger adults.
Mostrar más [+] Menos [-]Urinary metabolites of multiple volatile organic compounds among general population in Wuhan, central China: Inter-day reproducibility, seasonal difference, and their associations with oxidative stress biomarkers Texto completo
2021
Qian, Xi | Wan, Yanjian | Wang, Aizhen | Xia, Wei | Yang, Zong | He, Zhenyu | Xu, Shunqing
General population are concurrently and extensively exposed to many volatile organic compounds (VOCs), including some Group 1 human carcinogens, such as 1,3-butadiene. However, only a few studies assessed internal exposure levels of VOCs; particularly, very limited studies have examined associations between the urinary concentrations of multiple VOC metabolites (mVOCs) and oxidative stress biomarkers (OSBs) among the general population. In this study, 21 mVOCs and three OSBs including 8-hydroxy-2′-deoxyguanosine (8-OHdG; for DNA), 8-hydroxyguanosine (8-OHG; for RNA), and 4-hydroxy nonenal mercapturic acid (HNEMA; for lipid) were measured in 406 urine samples collected from 128 healthy adults during autumn and winter of 2018 in Wuhan, central China, including repeated samples taken in 3 d from 75 volunteers. Inter-day reproducibility for most mVOCs was good to excellent; urinary concentrations of mVOCs in winter were generally higher than those in autumn. Risk assessment was conducted by calculating hazard quotients for the parent compounds, and the results suggested that acrolein, 1,3-butadiene, and cyanide should be considered as high-priority hazardous ones for management. After false-discovery adjustment, 16 of the studied mVOCs were positively associated with 8-OHdG and 8-OHG (β values ranged from 0.04 to 0.48), and four mVOCs were positively associated with HNEMA (β values ranged from 0.21 to 0.78). Weighted quantile sum regression analyses were used to assess associations of mVOC mixture and OSBs, and we found significantly positive associations between the mixture index and OSBs, among which the strongest mVOC contributors for the associations were 2-methylhippuric acid for both DNA (20%) and RNA (17%) oxidative damage, and trans,trans-muconic acid (50%) for lipid peroxidation. This study firstly reported good to excellent short-term reproducibility, seasonal difference in autumn and winter, and possible health risk in urinary concentrations of multiple mVOCs among the general population.
Mostrar más [+] Menos [-]Spatial and temporal trends in mercury levels in the down of black stork chicks in central Europe Texto completo
2021
Kucharska, Katarzyna | Binkowski, Łukasz J. | Dudzik, Krzysztof
Piscivorous avian species may be affected by mercury (Hg) which tends to accumulate in aquatic environments and biomagnifies across the food webs. One of such species is the black stork, whose population increase recently slowed down due to unknown reasons. At the same time Hg contamination and its effects were almost unaudited for this species, so it may have exerted deleterious effects on the population and an evaluation is necessary. This is the first study of this species concerning Hg contamination. Thus, Hg concentrations were investigated in the down of black stork chicks (N = 90) from breeding locations in central and southern Poland (Europe) between 2015 and 2017. As well as Hg levels, morphometric parameters and age were evaluated. Mean Hg concentrations reached 0.7 μg/g d.w. and differed significantly between years, from the lowest value noted in 2017 (mean 0.5 μg/g), through 2016 (0.7 μg/g), to the highest one in 2015 (0.9 μg/g), and between nest locations where higher Hg levels were generally found in northern parts of the study area. Hg concentrations were also unrelated to morphometric parameters. Contrarily, morphometric parameters revealed high correlations between themselves, which was confirmed by the cluster analysis (revealing only two clusters) and principal component analysis (the first PC explained 96.8% of the variance). Hg levels in the down of black storks were rather low with the fluctuation between years and nest locations probably caused by parental exposure during wintering, migration, pre-breeding season and recent exposure through food provided by parents. Such low Hg concentrations seemed not to affect the population from the region studied.
Mostrar más [+] Menos [-]Evaluating the genesis and dominant processes of groundwater salinization by using hydrochemistry and multiple isotopes in a mining city Texto completo
2021
Chen, Xing | Jiang, Chunlu | Zheng, Liugen | Zhang, Liqun | Fu, Xianjie | Chen, Shigui | Chen, Yongchun | Hu, Jie
The increasing salinization of groundwater renders it challenging to maintain the water quality. Moreover, knowledge regarding the characteristics and mechanism of groundwater salinization in mining areas remains limited. This study represents the first attempt of combining the hydrochemical, isotope (δD, δ¹⁸O, δ³⁷Cl, and ⁸⁷Sr/⁸⁶Sr) and multivariate statistical analysis methods to explore the origin, control, and influence of fluoride enrichment in mining cities. The TDS content of groundwater ranged from 275.9 mg/L to 2452.0 mg/L, and 54% of the groundwater samples were classified as class IV water according to China's groundwater quality standards (GB/T 14848–2017), indicating a decline in the water quality of the study area. The results of the groundwater ion ratio and isotope discrimination analysis showed that dissolution and evaporation involving water-rock interactions and halite were the main driving processes for groundwater salinization in the study area. In addition to the hydrogeological and climatic conditions, mine drainage inputs exacerbated the increasing salinity of the groundwater in local areas. The mineral dissolution, cation exchange, and evaporation promoted the F⁻ enrichment, while excessive evaporation and salinity inhibited the F⁻ enrichment. Gangue accumulation and infiltration likely led to considerable F⁻ enrichment in individual groundwater regions. Extensive changes in the groundwater salinity indicated differences in the geochemical processes that controlled the groundwater salinization. Given the particularity of the study area, the enrichment of salinization and fluoride triggered by mining activities cannot be ignored.
Mostrar más [+] Menos [-]Foliar application of the sulfhydryl compound 2,3-dimercaptosuccinic acid inhibits cadmium, lead, and arsenic accumulation in rice grains by promoting heavy metal immobilization in flag leaves Texto completo
2021
Yang, Xiaorong | Wang, Changrong | Huang, Yongchun | Liu, Bin | Liu, Zhongqi | Huang, Yizong | Cheng, Liulong | Huang, Yanfei | Zhang, Changbo
Mixed pollution due to heavy metals (HMs), especially cadmium (Cd), lead (Pb), and arsenic (As), seriously endangers the safety of food produced in paddy soil. In the field experiments, foliar application of 2,3-dimercaptosuccinic acid (DMSA) at the flowering stage was found to significantly reduce the levels of Cd, Pb, total As, and inorganic As (iAs) in rice grains by 47.95%, 61.76%, 36.37%, and 51.24%, respectively, without affecting the concentration of metallonutrients, including Mn, K, Mg, Ca, Fe, and Zn. DMSA treatment significantly reduced the concentrations of Cd, Pb, and As in the panicle node, panicle neck, and rachis, while those in the flag leaves were significantly increased by up to 20.87%, 49.40%, and 32.67%, respectively. DMSA application promoted the transport of HM from roots and lower stalks to flag leaves with a maximum increase of 34.55%, 52.65%, and 46.94%, respectively, whereas inhibited the transport of HM from flag leaves to panicle, rachis, and grains. Therefore, foliar application of DMSA reduced Cd, Pb, and As accumulation in rice grains by immobilizing HMs in flag leaves. Thus, this strategy could act as a promising agronomic measure for the remediation of mixed HM contamination in paddy fields.
Mostrar más [+] Menos [-]A novel method for organic matter removal from samples containing microplastics Texto completo
2021
Lavoy, Mercedes | Crossman, Jill
Sludge and biosolids from wastewater treatment plants (WWTPs), identified as important pathways through which microplastics (MPs) can enter the wider environment, contain high organic content, which can obstruct MP quantification/identification. Time- and cost-effective removal of organics is a significant barrier to MP analysis. This study aims to alleviate these obstacles using a widely available store-bought septic tank cleaner, comprised of enzymes and bacteria. The cleaner was added to sludge samples, obtained from a local WWTP. Digestion was tested across a range of cleaner concentrations and heat treatments, and compared to a control digestion without cleaner. Organic content of samples digested with cleaner was reduced by 93%, representing a 22% greater reduction compared to control samples. Virgin plastic pellets, of a variety of polymers, were subjected to the digestion process and underwent no physical or chemical changes, demonstrating this method does not degrade MPs. As all enzymes were added in a single step, the time required for enzymatic digestion using the cleaner was only two days. Compared to existing methods, which take up to several weeks, this novel enzymatic digestion method offers a viable means of extracting MPs from organic materials without either the long processing times required of chemical (solely Fenton's) methods or high cost of laboratory grade enzyme approaches.
Mostrar más [+] Menos [-]Global greenhouse vegetable production systems are hotspots of soil N2O emissions and nitrogen leaching: A meta-analysis Texto completo
2021
Qasim, Waqas | Xia, Longlong | Lin, Shan | Wan, Li | Zhao, Yiming | Butterbach-Bahl, Klaus
Vegetable production in greenhouses is often associated with the use of excessive amounts of nitrogen (N) fertilizers, low NUE (15–35%), and high N losses along gaseous and hydrological pathways. In this meta-analysis, we assess the effects of application rate, fertilizer type, irrigation, and soil properties on soil N₂O emissions and nitrogen leaching from greenhouse vegetable systems on the basis of 75 studies. Mean ± standard error (SE) N₂O emissions from unfertilized control plots (N₂Ocₒₙₜᵣₒₗ) and N leaching (NLcₒₙₜᵣₒₗ) of greenhouse vegetable systems were 3.2 ± 0.4 and 91 ± 20 kg N ha⁻¹ yr⁻¹, respectively, indicating legacy effects due to fertilization in preceding crop seasons. Soil organic carbon concentrations (SOC) and irrigation were significantly positively correlated with NLcₒₙₜᵣₒₗ losses, while other soil properties did not significantly affect N₂Ocₒₙₜᵣₒₗ or NLcₒₙₜᵣₒₗ. The annual mean soil N₂O emission from fertilized greenhouse vegetable systems was 12.0 ± 1.0 kg N₂O–N ha⁻¹ yr⁻¹ (global: 0.067 Tg N₂O–N yr⁻¹), with N₂O emissions increasing exponentially with fertilization. The mean EFN₂O was 0.85%. The mean annual nitrogen leaching (NL) was 297 ± 22 kg N ha⁻¹ yr⁻¹ (global: 1.66 Tg N yr⁻¹), with fertilization, irrigation, and SOC explaining 65% of the observed variation. The mean leaching factor across all fertilizer types was 11.9%, but 18.7% for chemical fertilizer. Crop NUE was highest, while N₂O emissions and N leaching were lowest, at fertilizer rates <500 kg N ha⁻¹ year⁻¹. Yield-scaled N₂O emissions (0.05 ± 0.01 kg N₂O–N Mg⁻¹ yr⁻¹) and nitrogen leaching (0.79 ± 0.08 kg N Mg⁻¹ yr⁻¹) were lowest at fertilizer rates <1000 kg N ha⁻¹ yr⁻¹. Vegetables are increasingly produced in greenhouses, often under management schemes of extreme fertilization (>1500 kg N ha⁻¹ yr⁻¹) and irrigation (>1200 mm yr⁻¹). Our study indicates that high environmental N₂O and N leaching losses can be mitigated by reducing fertilization rates to 500–1000 kg N ha⁻¹ yr⁻¹ (mean: ∼762 kg N ha⁻¹ yr⁻¹) without jeopardizing yields.
Mostrar más [+] Menos [-]Polycyclic aromatic compounds in the Canadian Environment: Aquatic and terrestrial environments Texto completo
2021
Marvin, Christopher H. | Berthiaume, Alicia | Burniston, Deborah A. | Chibwe, Leah | Dove, Alice | Evans, Marlene | Hewitt, L Mark | Hodson, Peter V. | Muir, Derek C.G. | Parrott, Joanne | Thomas, Philippe J. | Tomy, Gregg T.
Polycyclic aromatic compounds (PACs) are ubiquitous across environmental media in Canada, including surface water, soil, sediment and snowpack. Information is presented according to pan-Canadian sources, and key geographical areas including the Great Lakes, the Alberta Oil Sands Region (AOSR) and the Canadian Arctic. Significant PAC releases result from exploitation of fossil fuels containing naturally-derived PACs, with anthropogenic sources related to production, upgrading and transport which also release alkylated PACs. Continued expansion of the oil and gas industry indicates contamination by PACs may increase. Monitoring networks should be expanded, and include petrogenic PACs in their analytical schema, particularly near fuel transportation routes. National-scale roll-ups of emission budgets may not expose important details for localized areas, and on local scales emissions can be substantial without significantly contributing to total Canadian emissions. Burning organic matter produces mainly parent or pyrogenic PACs, with forest fires and coal combustion to produce iron and steel being major sources of pyrogenic PACs in Canada. Another major source is the use of carbon electrodes at aluminum smelters in British Columbia and Quebec. Temporal trends in PAC levels across the Great Lakes basin have remained relatively consistent over the past four decades. Management actions to reduce PAC loadings have been countered by increased urbanization, vehicular emissions and areas of impervious surfaces. Major cities within the Great Lakes watershed act as diffuse sources of PACs, and result in coronas of contamination emanating from urban centres, highlighting the need for non-point source controls to reduce loadings.
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