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17581. 题目: Pollution control in biochar-driven clean composting: Emphasize on heavy metal passivation and gaseous emissions mitigation
文章编号: N21071620
期刊: Journal of Hazardous Materials
作者: Yumin Duan, Jianfeng Yang, Yaru Guo, Xiaoping Wu, Yuli Tian, Huike Li, Mukesh Kumar Awasthi
更新时间: 2021-07-16
摘要: Present study was focus on the pollution control aspect of gaseous mitigation and heavy metal passivation as well as their associated bacterial communities driven by apple tree branch biochar (BB) during sheep manure composting. Six treatment was performed with distinct concentration of BB from 0%, 2.5%, 5%, 7.5%, 10%, and 12.5% as T1 to T6. Compared with compost without additive, biochar-based composting recorded faster thermophilic process (4thd) and longer duration (12-14d), lower gaseous emission in terms of ammonia (5.37-10.29g), nitrous oxide (0.12-0.47g) and methane (4.38-30.29g). Notably highest temperature (65.3℃) and active thermophilic duration (14d), minimized gaseous volatilization were detected in 10%BB composting. Aspect of non-degradability and enrichment-concentration properties of heavy metals, the total copper (Cu) and zinc (Zn) were increased (from initial 12.71-17.91 to final 16.36-29.36mg/kg and 107.39-146.58 to 161.48-211.91mg/kg). In view of available diethylene triamine pentacetic acid (DTPA) extractable form, DTPA-Cu and DTPA-Zn from 4.29-6.57 and 31.66-39.32mg/kg decreased to 3.75-4.82 and 23.43-40.54mg/kg, especially the maximized passivation rate of 46.95% and 56.27% were present in 10%BB composting. Additionally, bacterial diversity of biochar-based composting was increased (1817-2310 OTUs) than control (1686 OTUs) and dominant by Firmicutes (52.75%), Bacteroidetes (28.41%) and Actinobacteriota (13.98%). Validated 10% biochar-based composting is the optimal option for effectively control environmental pollution to obtain hygienic composting.

17582. 题目: Application of humin-immobilized biocathode in a continuous-flow bioelectrochemical system for nitrate removal at low temperature
文章编号: N21071619
期刊: Environmental Research
作者: Dan Chen, Lizhuang Yang, Zhiling Li, Zhixing Xiao
更新时间: 2021-07-16
摘要: Solid-phase humic substances (humin) can work as an additional electron donor to support the low temperature denitrification but the reducing capacity of its non-reduced form is limited. In this study, a continuous-flow denitrifying BES with a humin-immobilized biocathode (H-BioC) was established. Humin was expected to function as a redox mediator and be persistently reduced on the cathode to provide reducing power to a denitrifying biofilm. Results showed that the H-BioC maintained a stable denitrification capacity with low nitrite accumulation for more than 100 days at 5 °C, and the specific microbial denitrification rate and electron transfer rate were 3.97-fold and 1.75-fold higher than those of the unaltered cathode. The results of repeated cycles of humin reduction and oxidation experiments further suggested that the redox activity of humin was stable. Acidovorax was the most dominant genus in both H-BioC biofilm and unaltered cathodic biofilm, while Rhodocyclaceae (unclassified_f_) was more enriched in H-BioC biofilm. Further Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) analyses indicated that biofilm formation, electron transfer, and nitrate reduction functions were more abundant in H-BioC, suggesting a possible enhancement mechanism by humin. The results of this study raise the possibility that immobilization of solid-phase humin may be a useful strategy for electrostimulated heterotrophic denitrification in groundwater where the indigenous bacteria have poor electroactivity.

17583. 题目: Biochar aging alters the bioavailability of cadmium and microbial activity in acid contaminated soils
文章编号: N21071618
期刊: Journal of Hazardous Materials
作者: Tharanga Bandara, Ashley Franks, Jianming Xu, J.B.A.J. Chathurika, Caixian Tang
更新时间: 2021-07-16
摘要: The effects of biochar aging on heavy-metal bioavailability and microbial activity are not fully understood. This study determined the effect over 270 days of poultry-litter biochar (PBC) and sugar-gum-wood biochar (SBC) on the bioavailability of Cd and microbial activity in acidic soils differing in organic matter content. Soil basal and substrate-induced respirations, microbial properties, Cd bioavailability and plant Cd bioaccumulation were evaluated at 1, 30, 90 and 270 days. The addition of PBC decreased Cd bioaccumulation by 81% and 85% while SBC decreased bioaccumulation by 47% and 56% in high (Chromosol) and low (Sodosol) organic matter soils, respectively, at Day 1. By Day 270, Cd bioaccumulation significantly (P < 0.05) increased in SBC-amended soils but decreased in PBC-amended soils. The addition of PBC increased both basal and substrate-induced microbial respirations compared to the other treatments over 270-day aging. However, SBC increased microbial biomass C compared to the PBC after Day 30. Aging decreased microbial respiration and biomass C in biochar-amended soils. It is concluded that Cd bioaccumulation increased in SBC-amended soils during aging whereas the PBC decreased Cd bioaccumulation of Cd and that the selection of biochar is important to enhanced remediation efficiency in the long term.

17584. 题目: Interaction kinetics and accessibility of sulfadiazine in model clay-humic acid suspension: Electron spin resonance investigations with nitroxide spin label
文章编号: N21071617
期刊: Science of The Total Environment
作者: Adrian Ricke, Tamás Kálai, Heinz-Jürgen Steinhoff, Michael Matthies
更新时间: 2021-07-16
摘要: The characterization of the interaction of sulfonamides with soil is of particular interest in environmental risk and persistence assessment. In the present work electron spin resonance spectroscopy (ESR) was used to investigate the interaction kinetics of spin labelled sulfadiazine (SL-SDZ) with model clay-humic acid suspensions. The ESR spectra showed that SL-SDZ incubated with Leonardite humic acid (LHA) and Ca-hectorite as model clay was immobilized due to covalent binding of its aniline moiety to LHA. From the immobilization kinetics measured over a period of 1200 h a pseudo-first order reaction with a time constant of 82.6 ± 25.0 h of covalent binding was determined. Additionally, SL-SDZ was strongly sorbed by LHA immediately after incubation but not durably sequestered. Compared to incubation without Ca-hectorite the covalent binding kinetics of SL-SDZ as well as its strong sorption were retarded.

17585. 题目: Methane oxidation activity inhibition via high amount aged biochar application in paddy soil
文章编号: N21071616
期刊: Science of The Total Environment
作者: Qiong Nan, Senlin Hu, Yong Qin, Weixiang Wu
更新时间: 2021-07-16
摘要: Fresh biochar application has been recommended as an effective strategy to mitigate methane emissions from paddy soil due to its role in promoting potential methane oxidation (PMO). However, little is known about the effect of biochar on PMO after long-term aging. Here, a laboratory incubation experiment was performed to gain insight into the combined effects of biochar characteristics on soil PMO during the biochar aging process. Biochar samples aged with an HNO3/H2SO4 mixture (1:3) were prepared and added at 22.5 and 2.8 t ha-1 to paddy soil. Mixed acid with a dilution of 10– 40% indicated the aging process in paddy field properly. Smaller biochar particles, smoother surface, higher surface area and porosity were observed with the increase of mixed acid ratio. Carboxylic functional groups (COOR) on biochar surface increased accompanied with biochar aging process. Aged biochar application at 22.5 t ha-1 inhibited paddy soil PMO, which mainly caused from the increased COOR groups induced NH4+-N inhibition for PMO. Increased soil NH4+-N inhibited PMO by limiting the growth of methanotrophs and nitrifiers due to decreased soil pH. In contrast, 2.8 t aged biochar ha-1 application showed no significant difference on PMO compared with control. Our results indicated that aged biochar exerted in paddy soil have limited effect on mitigating methane emissions from paddy soil in the long term.

17586. 题目: Effect of KH2PO4-modified biochar on immobilization of Cr, Cu, Pb, Zn and As during anaerobic digestion of swine manure
文章编号: N21071615
期刊: Bioresource Technology
作者: Shuo Yang, Qinxue Wen, Zhiqiang Chen
更新时间: 2021-07-16
摘要: In this study, the immobilization performance and mechanisms of heavy metals (HMs) in swine manure (SM) during anaerobic digestion (AD) with biochar (BC) and KH2PO4-modified biochar (BP) were investigated. BC and BP addition decreased DTPA-extractable Cr, Cu, Pb and Zn amount, transformed these HMs to more stable state, and decreased the ecological risks of these HMs by 2 grades accordingly. BP exhibited a higher passivation efficiency for Cr, Cu and Pb and 5% -10% biochar dosage showed the maximum passivation effects. Characterization results showed that Cr, Cu and Pb immobilization with BP were mainly attributed to the formation of phosphate precipitation. However, both DTPA extraction and mobility of As increased with biochar addition, because the release of phosphorus in biochar had negative effect on As immobilization. BP could serve as a novel remediation agent for Cr, Cu, Pb and Zn passivation but special attention should be paid with As presence.

17587. 题目: Insight investigation of the on-site activated sludge reduction induced by metabolic uncoupler: Effects of 2,6-dichlorophenol on soluble microbial products, microbial activity, and environmental impact
文章编号: N21071614
期刊: Chemosphere
作者: QingYuan Lin, Jun Zhang, Linlin Yin, Wei Zuo, Lipin Li, Yu Tian
更新时间: 2021-07-16
摘要: Metabolic uncoupling technology was one of the methods widely used to on-site control the production of excess sludge in wastewater treatment processes. However, the uncoupler effects on soluble microbial products (SMP), microbial activity, and environment impact have few been reported. This study showed that sludge yield was reduced by 33.3% at 2,6-dichlorophenol (2,6-DCP) concentrations of 10 mg/L. The addition of 2,6-DCP also reduced the content of polysaccharide and protein in SMP, and the three-dimension excitation emission matrix (3D-EEM) suggested that the fluorescence intensities of humic acid-like, fulvic acid-like, and tryptophan protein-like substances decreased, proving that 2,6-DCP addition will weaken the interaction between microorganisms and the environmental matrix. Moreover, 2,6-DCP addition will change the microbial morphology and community of activated sludge. The active or respiring bacteria portion was lessened, and sludge flocs become dispersed, but it will not affect its settling performance. Surprisingly, 2,6-DCP has certain biodegradability and could be used as an environmentally friendly metabolic uncoupler under low-concentration dosing conditions. This study systematically evaluated the effect of 2,6-DCP on sludge production, SMP contents, microbial morphology, microbial community, demonstrating the environmental impact and application feasibility in the wastewater treatment systems.

17588. 题目: Biomass as source for hydrochar and biochar production to recover phosphates from wastewater: A review on challenges, commercialization, and future perspectives
文章编号: N21071613
期刊: Chemosphere
作者: Sivaprasad Shyam, Jayaseelan Arun, Kannappan Panchamoorthy Gopinath, Gautam Ribhu, Manandhar Ashish, Shah Ajay
更新时间: 2021-07-16
摘要: Excessive phosphate run-off with total phosphorus concentration greater than 20 μg P L −1 triggers the growth of harmful algal species in waterbodies and potentially leads to eutrophication. This has severe negative implications on aquatic environment and impacts human health. The annual economic impact of harmful algal blooms is reported to be as high as $25 million for public health and commercial fishery sector, $29 million for recreation/tourism sector and $2 million for monitoring and management. Adsorption is widely considered as an effective and economic strategy to achieve extremely low concentration of phosphorus. The char produced by valorizing various waste biomasses have been gaining attention in phosphorus remediation owing to their availability, their ability to regenerate and reuse. This review paper exclusively focuses on utilizing hydrochar and biochar synthesized from waste biomass, respectively, through hydrothermal carbonization and slow pyrolysis to mitigate phosphorus concentration and potential strategies for handling the spent char. The key mechanisms involved in phosphate adsorption are electrostatic interaction, ion exchange and complexation. The maximum adsorption capacity of hydrochar and biochar ranges from 14 - 386 mg g−1 and 3–887 mg g −1, respectively. Hydrochar and biochar are cost-effective alternative to commercial activated carbon and spent char can be used for multiple adsorption cycles. Furthermore, extensive research studies on optimizing the feedstock, reaction and activation conditions coupled with technoeconomic analysis and life cycle assessment could pave way for commercialization of char-based adsorption technology.

17589. 题目: Mechanism for various phytotoxicity of atrazine in soils to soybean: Insights from soil sorption abilities and dissolved organic matter properties
文章编号: N21071612
期刊: Journal of Environmental Management
作者: Ying Zhang, Chao Yang, Zhi Zheng, Bo Cao, Fengyuan You, Yingying Liu, Zhao Jiang
更新时间: 2021-07-16
摘要: The pollutants in soils with different physicochemical properties usually exhibit various phytotoxicity due to their diverse environmental behavior. However, it is not clear that some components of dissolved organic matter (DOM) in soil affect the bioavailability of pollutants. In this study, the different phytotoxicity of atrazine in two different soils, black soil (BS) and yellow brown earth (YBE), to soybeen seedlings was investigated, and the potential mechanism were further discussed by examining the adsorption properties of atrazine with BS and YBE as well as the fluorescent characteristic variation of these two kinds of DOM extracted from BS and YBE during binding with atrazine. The results suggest that atrazine showed different phytotoxicity to soybean seedlings grown in BS and YBE. Specifically, the EC50 of atrazine on plant height and root length of soybean seedling in BS were 23.44 mg kg−1 and 54.29 mg kg−1, while those in YBE were 12.79 mg kg−1 and 21.48 mg kg−1. The adsorption amounts of BS and YBE was 41.56 mg kg−1 and 32.95 mg kg−1. In addition, 3D-EEM showed that humic acid-like substances were the main components of DOM in the two soils. With the increase of atrazine concentration, the fluorescence of these two kind of DOM was gradually quenched, but DOM-BS had a faster quenching rate. FT-IR showed that DOM-BS contained more polysaccharides and richer lipophilic groups. Meanwhile, the results of PARAFAC found that DOM-BS was easier to combine with atrazine. The findings of this study are significant to reveal phytotoxicity of atrazine in BS and YBE. The above results are helpful to better understand the components of DOM in different soils and their different role in regulating the environmental behavior and phytotoxicity of organic pollutants.

17590. 题目: Fungal–fungal and fungal–bacterial interactions in aquatic decomposer communities: bacteria promote fungal diversity
文章编号: N21071611
期刊: Ecology
作者: Patrick Baudy, Jochen P. Zubrod, Marco Konschak, Sara Kolbenschlag, Annika Pollitt, Christiane Baschien, Ralf Schulz, Mirco Bundschuh
更新时间: 2021-07-16
摘要: Fungi produce a variety of extracellular enzymes making recalcitrant substrates bioavailable. Thus, fungi are central for decomposition of dead organic matter such as leaf litter. Despite their ecological importance, our understanding of relationships between fungal species diversity and ecosystem functioning is limited, especially with regard to aquatic habitats. Moreover, fungal interactions with other groups of microorganisms such as bacteria are rarely investigated. This lack of information may be attributed to methodological limitations in tracking the biomass of individual fungal species in communities, impeding a detailed assessment of deviations from the overall performance expected from the sum of individual species’ performances, so-called net diversity effects (NDEs). We used fungal species-specific biomolecular tools to target fungal–fungal and fungal–bacterial interactions on submerged leaves using four cosmopolitan aquatic fungal species and a stream microbial community dominated by bacteria. In microcosms, we experimentally manipulated fungal diversity and bacterial absence/presence and assessed functional performances and fungal community composition after 14 days of incubation. Fungal community data was used to evaluate NDEs on leaf colonization. The individual fungal species were functionally distinct and fungal cultures were on average more efficient than the bacterial culture. In absence of bacteria, NDEs correlated with growth rate (negatively) and genetic divergence (positively), but were predominantly negative, suggesting that higher fungal diversity led to a lower colonization success (niche overlap). In both absence and presence of bacteria, the overall functional performances of the communities were largely defined by their composition (i.e., no interactions at the functional level). In presence of bacteria, NDEs correlated with genetic divergence (positively) and were largely positive, suggesting higher fungal diversity stimulated colonization (niche complementarity). This stimulation may be driven by a bacteria-induced inhibition of fungal growth, alleviating competition among fungi. Resulting feedback loops eventually promote fungal coexistence and synergistic interactions. Nonetheless, overall functional performances are reduced compared to bacteria-free cultures. These findings highlight the necessity to conduct future studies, investigating biodiversity-ecosystem functioning relationships using artificial systems, without exclusion of key organisms naturally co-occurring in the compartment of interest. Otherwise, study outcomes might not reflect true ecological relationships and ultimately misguide conservation strategies.

17591. 题目: Natural and anthropogenically driven changes in the n-alkanols of lake sediments and implications for their use in paleoenvironmental studies of lakes
文章编号: N21071610
期刊: CATENA
作者: Yongdong Zhang, Ting Peng, Jinlei Yu, Yaling Su, Zhengwen Liu
更新时间: 2021-07-16
摘要: In order to examine how natural backgrounds and anthropogenic activities influenced the n-alkanol profiles of lake sediments, abundances and compositions of n-alkanols were determined in sediment cores taken from four lakes with notable differences in depth, nutrient level, transparency, water residence time and human impact. The results indicate the short-chain n-alkanols (C14, C16 and C18) are generally more abundant in sediments from eutrophic lakes than in oligotrophic bodies, due to greater inputs from algae and zooplankton. In individual lakes, however, high levels of short-chain n-alkanols were not always recorded in sediments of relatively eutrophic phases because contributions from zooplankton can be significant even if the lake remains relatively oligotrophic. The >C20 n-alkanol profiles varied markedly between shallow and deep lakes. A prevalence of long-chain compounds (C26, C28, C30 and C32) was observed in shallow lakes and is attributable to terrestrial organic matter (OM) carried by inflowing rivers, whose relatively huge annual input is evidenced by the short water residence time in these lakes. Sediments from deep lakes were dominated by middle-chain n-alkanols (C20, C22 and C24) as a result of significant input from submersed macrophytes, which achieve high productivity in the clear, sunlit water. In shallow lakes, (C26 + C28)/(C22 + C24) n-alkanol ratios in sediments were greatly dependent on anthropogenic eutrophication and aquaculture via their influence on the productivity of submersed macrophytes.

17592. 题目: Safety and efficiency of sewage sludge and garden waste compost as a soil amendment based on the field application in woodland
文章编号: N21071609
期刊: Ecotoxicology and Environmental Safety
作者: Yongshuang Li, Bo Sun, Tingyue Deng, Peng Lian, Juhong Chen, Xiawei Peng
更新时间: 2021-07-16
摘要: Sewage sludge (SS) and garden waste (GW) compost can be used as soil amendments to improve the soil environment. Studies done till date have been focused on the changes of harmful substances during sludge composting, but the safety and efficacy of SS and GW composting on woodland soil environment are still unclear. In the study, a field experiment was performed using to investigate the safety and efficacy of SS and GW compost as a soil amendment on woodland soil. Soil nutrients (such as nitrogen, phosphorus and potassium), organic matter and electrical conductivity were significantly increased after the addition of the SS and GW compost, while there were no significant changes in soil heavy metals content and soil enzyme activities. From these soil properties, it was found that SS and GW compost was safe and efficacious in improving the soil environment. The application of SS and GW compost had no significant effect on microbial diversity. Co-occurrence network analysis revealed that SS and GW compost efficaciously enhanced the interaction between bacterial communities, which proved that it was safe and efficacious. Furthermore, SS and GW compost enhanced ABC transporters and carbohydrate metabolism of bacterial community, while reduced the pathotroph action (such as the plant pathogen) and wood saprotrophs. Overall, these results proved the safety and efficacy of SS and GW compost as soil amendments after being added to the soil. This study contributes to the use of harmless treatments and reutilization processes of SS and GW.

17593. 题目: Stabilization of soil organic carbon in the alpine meadow is dependent on the nitrogen deposition level on the Qinghai-Tibetan Plateau
文章编号: N21071608
期刊: Ecological Engineering
作者: Jiannan Xiao, Shikui Dong, Zhenzhen Zhao, Yuhui Han, Shuai Li, Hao Shen, Chengxiang Ding
更新时间: 2021-07-16
摘要: The Qinghai-Tibet Plateau (QTP) is experiencing increasing nitrogen (N) deposition, which may have great impacts on the physical, chemical, and biological factors that determine the stabilization of soil organic carbon (SOC). However, few studies have been conducted to quantify the relative contributions of these factors to SOC stabilization at various N addition levels in alpine habitats. We established a N manipulation experiment from 2015 to 2016 in an alpine meadow on the QTP to examine the impacts of N addition gradients on SOC stabilization under different scenarios of N deposition including 8, 24, 40, 56, and 72 kg N ha−1 yr−1. Using solid-state 13C NMR spectroscopy, we assessed the changes in the chemical composition of SOC. We measured soil aggregate size fractions, iron ions, soil microbes, and soil chemicals to investigate their contributions to SOC stabilization. We found that there were response thresholds of SOC to N addition in this alpine meadow on the QTP. The critical level of N addition for the change of SOC was close to 16 kg N ha−1 yr−1 plus the natural atmospheric N deposition (approximately 8 kg N ha−1 yr−1). N addition affected SOC stabilization in this alpine meadow mainly by affecting soil aggregates and soil microbes. These results of this study suggest that an exogenous N input lower than the critical load is beneficial for C sequestration in this alpine meadow on the QTP. This is potentially important for understanding the influences of atmospheric N deposition on soil properties, with subsequent effects on SOC stabilization on the alpine meadow of QTP and similar fragile ecosystems worldwide.

17594. 题目: Sulfur dynamics in forest soil profiles developed on granite under contrasting climate conditions
文章编号: N21071607
期刊: Science of The Total Environment
作者: Zhuojun Zhang, Hairuo Mao, Zhi-Qi Zhao, Lifeng Cui, Shilu Wang, Cong-Qiang Liu
更新时间: 2021-07-16
摘要: Sulfur (S) dynamics in soils formed from granite remain poorly understood despite its importance as an essential plant macronutrient and component of soil organic matter. We used stable S isotope ratios to trace the sources and biogeochemical processes of S in four forest soil profiles developed on granite under contrasting climate conditions. The soil S is derived mainly from decomposing litter; no significant geogenic contribution to its content is noted as a result of the low S concentration of the granite (~5 μg/g). Colder/drier climate results in high organic S retention at the surface due to weak mineralization of organic S. Although warmer/wetter climate increases the S mineralization and leaching loss, SO42− adsorption is an important S retention process in the subsurface. The vertical distribution of S isotope compositions in the soil profiles across the four sites indicates (i) a downward increase in δ34S values in the upper profiles due to continuous mineralization of organic S with an occasional decrease in δ34S values in the subsurface due to dissimilatory sulfate reduction (DSR), (ii) constantly high δ34S values in the middle profiles due to the low water permeability, and (iii) a downward decrease in δ34S values in the low profiles due to increased contribution of bedrock with depth. Regardless of the variation in soil depth and climate, the total S concentration is proportional to the pedogenic Fe/Al minerals, suggesting the important role of secondary Fe/Al minerals in retaining S in soils. This study provides an integration and synthesis of controls of climatic and edaphic variables on S dynamics in forest soil profiles developed on granite.

17595. 题目: Dissimilatory nitrate reduction and functional genes in two subtropical rivers, China
文章编号: N21071606
期刊: Environmental Science and Pollution Research
作者: Binjie Zhao, Xinshuai Li, Yang Wang, Xiang Tan, Wenhua Qi, Hongran Li, Junwei Wei, Yong You, Wenjun Shi, Quanfa Zhang
更新时间: 2021-07-16
摘要: Dissimilatory nitrate reduction processes, including denitrification, anaerobic ammonium oxidation (anammox), and dissimilatory nitrate reduction to ammonium (DNRA), are important pathways of nitrate transformation in the aquatic environments. In this study, we investigated potential rates of denitrification, anammox, and DNRA in the sediments of two subtropical rivers, Jinshui River and Qi River, with different intensities of human activities in their respective catchment, China. Our objectives were to assess the seasonality of dissimilatory nitrate reduction rates, quantify their respective contributions to nitrate reduction, and reveal the relationship between dissimilatory nitrate reduction rates, functional gene abundances, and physicochemicals in the river ecosystems. Our results showed higher rates of denitrification and anammox in the intensively disturbed areas in autumn and spring, and higher potential DNRA in the slightly disturbed areas in summer. Generally, denitrification, anammox, and DNRA were higher in summer, autumn, and spring, respectively. Relative contributions of nitrate reduction from denitrification, anammox, and DNRA were quite different in different seasons. Dissimilatory nitrate reduction rates and gene abundances correlated significantly with water temperature, dissolved organic carbon (DOC), sediment total organic carbon (SOC), NO3-, NH4+, DOC/NO3-, iron ions, and sulfide. Understanding dissimilatory nitrate reduction is essential for restoring nitrate reduction capacity and improving and sustaining ecohealth of the river ecosystems.

17596. 题目: Investigating atmospheric inputs of dissolved black carbon to the Santa Barbara Channel during the Thomas Fire (California, USA)
文章编号: N21071605
期刊: Journal of Geophysical Research: Biogeosciences
作者: Sasha Wagner, Elizabeth Harvey, Nicholas Baetge, Heather McNair, Eleanor Arrington, Aron Stubbins
更新时间: 2021-07-16
摘要: The Thomas Fire ignited on December 4, 2017 and burned for over one month. As the Thomas Fire burned, Santa Ana Winds carried a thick plume of smoke and ash over the Santa Barbara Channel. We sought to determine whether the deposition of Thomas Fire ash to the Santa Barbara Channel had a measurable effect on the concentration and stable carbon isotopic composition (δ13C) of dissolved black carbon (DBC) in coastal waters. DBC is the condensed aromatic fraction of thermally altered organic carbon quantified using the benzenepolycarboxylic acid (BPCA) method. DBC δ13C signatures were determined via BPCA-specific stable carbon isotopic analysis. Surface water DBC concentrations beneath the smoke plume were up to 13% higher than other sampling stations. Via controlled leaching experiments, we found that Thomas Fire ash released a considerable amount of DBC in seawater (1.4 g-DBC per kg of ash organic carbon), which was further enhanced by photodissolution. By combining in situ and experimental data, we constructed an isotopic mixing model to estimate inputs of ash-derived DBC to marine surface waters. Although we were able to detect slight elevations in DBC concentrations beneath the smoke plume, the ash-derived contributions were too small to meaningfully shift the δ13C signature, which resulted in an observed mismatch between modeled and measured DBC δ13C values. Few studies have investigated the immediate impacts of wildfire on coastal biogeochemistry. Therefore, our work provides an important foundation for understanding atmospheric contributions of fire-derived DBC to coastal margins.

17597. 题目: Simultaneous removal of toxic Pb(II) ions, poly(acrylic acid) and Triton X–100 from their mixed solution using engineered biochars obtained from horsetail herb precursor – impact of post-activation treatment
文章编号: N21071604
期刊: Separation and Purification Technology
作者: Małgorzata Wiśniewska, Piotr Nowicki, Katarzyna Szewczuk-Karpisz, Marlena Gęca, Katarzyna Jędruchniewicz, Patryk Oleszczuk
更新时间: 2021-07-16
摘要: The horsetail herb was used as the precursor and was subjected to direct physical activation with steam (800 °C for 1h). Next two variants of post-activation treatment was applied: (1) two–steps washing procedure, firstly with a hot 10% solution of HCl and later with demineralized water (HBA_HCl sample) and (2) one-step washing procedure only with demineralized water (HBA_H2O sample). The final products were characterized towards its textural structure, acid-base properties and surface morphology. The obtained biochars were used as adsorbents for simultaneous removal of hazardous lead(II) ions, poly(acrylic acid) (PAA) polymer and Triton X-100 nonionic surfactant from their mixed solution. It was shown that Pb(II) and PAA adsorbed amounts (from the single and mixed systems of adsorbates) have the greatest values on the HBA_HCl surface in the double PAA+Pb(II) system (148.8 mg/g and 195.8 mg/g, respectively) and in the triple PAA+TRT+Pb(II) system (183.3 mg/g and 187.7 mg/g, respectively). The nonionic surfactant desorption reaches high level (83-100%), independently from using desorption agent (HNO3 or NaOH). Generally in the case of PAA, NaOH solution turned out to be more effective in adsorbent recovery process (especially from HBA_H2O surface), whereas in the case of Pb(II) ions desorption, HNO3 is more effective desorbing agent (74-96% desorption).

17598. 题目: Transformation of Ammonium to Nitrophenolic Byproducts by Sulfate Radical Oxidation
文章编号: N21071603
期刊: Water Research
作者: Peizeng Yang, Yuefei Ji, Junhe Lu
更新时间: 2021-07-16
摘要: Sulfate radical (SO4•−) based oxidation shows great promise in wastewater treatment and subsurface remediation. For the first time, we demonstrated that SO4•− could induce the transformation of ammonium (NH4+) to nitrophenolic byproducts. Using high-resolution mass spectrometry in combination with 15N labeling, mono-nitro and di-nitro phenolic byproducts were identified in a sample containing 1 mM NH4+ and 10 mg/L natural organic matter (NOM) following heat activated peroxydisulfate (PDS) oxidation. At PDS dose of 1 mM, the formation of p-nitrophenol and 5-nitrosalicylic acid reached 0.21 and 0.30 μM, respectively, in 12 h and then decreased; the formation of 2,4-dinitrophenol and 3,5-dinitrosalicylic acid increased monotonically, reaching 0.37 and 0.62 μM, respectively, in 24 h. One-electron oxidation of NH4+ to form aminyl radicals (•NH2) was the first step of the transformation. The reaction of •NH2 with oxygen was a key step in propagating radical chain reactions, leading to nitrogen dioxide radicals (NO2•) as a key nitrating agent. The reactive sites susceptible to nitrating in NOM molecules are not limited to phenolic moieties. We found that aromatic carboxylate moieties could be in situ transformed to phenolics by SO4•−, thus contributed to nitrophenolic byproducts formation as well. Considering the ubiquitous presence of NH4+ in the environment, formation of nitrophenolic byproducts will be widespread when SO4•− is applied for onsite remediation, which should be taken into consideration when evaluating the feasibility of this technology.

17599. 题目: Significance of the presence of antibiotics on the microbial consortium in wastewater - the case of nitrofurantoin and furazolidone
文章编号: N21071602
期刊: Bioresource Technology
作者: Agata Zdarta, Wojciech Smułek, Zuzanna Bielan, Jakub Zdarta, Luong N. Nguyen, Agnieszka Zgoła-Grześkowiak, Long D. Nghiem, Teofil Jesionowski, Ewa Kaczorek
更新时间: 2021-07-16
摘要: Antibiotics presence in wastewater leads to migration of pollutants and disrupts natural processes of mineralization of organic matter. In order to understand the mechanism of this, research was undertaken on the influence of nitrofurantoin (NFT) and furazolidone (FZD), on the behaviour of a consortium of microorganisms present in a model wastewater in a bioreactor. Our study confirmed biodegradation of the antibiotics by the microbial consortium, with the degradation efficiency within 10 days of 65% for FZD, but only 20% for NFT. The kinetic study proved that the presence of analysed antibiotics had no adverse effect on the microbes, but the consortium behaviour differ significantly with the NFT reducing the consumption of organic carbon in wastewater and increasing the production of extracellular biopolymeric and volatile organic compounds, and the FZD reducing assimilation of other carbon sources to a less extent, at the expense of cellular focus on biodegradation of this antibiotic.

17600. 题目: Wheat and maize-derived water-washed and unwashed biochar improved the nutrients phytoavailability and the grain and straw yield of rice and wheat: A field trial for sustainable management of paddy soils
文章编号: N21071601
期刊: Journal of Environmental Management
作者: Punhoon Khan Korai, Tanveer Ali Sial, Genxing Pan, Hamada Abdelrahman, Ashim Sikdar, Farhana Kumbhar, Siraj Ahmed Channa, Esmat F. Ali, Jianguo Zhang, Jörg Rinklebe, Sabry M. Shaheen
更新时间: 2021-07-16
摘要: A field experiment was carried out to evaluate the effects of different biochars on grain yield and phytoavailability and uptake of macro- and micro-nutrients by rice and wheat grown in a paddy soil in a rotation. Soil was treated with i) maize raw (un-washed) biochar (MRB), ii) maize water-washed biochar (MWB), iii) wheat raw biochar (WRB) or iv) wheat water-washed biochar (WWB) and untreated soil was used as control (CF). Inorganic fertilizers were applied to all soils while biochar treated soils received 20 ton ha−1 of designated biochar before rice cultivation in rice-wheat rotation. The WRB significantly (P < 0.05) increased rice grain yield and straw by up to 49%, compared to the CF. Biochar addition, particularly WRB, significantly increased the availability of N, P, K and their content in the grain (26–37%) and straw (22–37%) of rice and wheat. Also, the availability and grain content of Fe, Mn, Zn, and Cu increased significantly after biochar addition, particularly after the WRB, due to WRB water dissolved C acting as a carrier for micronutrients in soil and plant. However, the water-washing process altered biochar properties, particularly the water extractable C, which decreased its efficiency. Both wheat- and maize-derived biochars, particularly the WRB, are recommended to improve nutrients availability and to improve grain yield in the rice-wheat rotation agro-ecosystem. These results shed light on the importance of crop straw transformation into an important source for soil C and nutrients necessary for sustainable management of wheat-rice agro-ecosystem. However, with the current and future alternative energy demands, the decision on using crop biomass for soil conservation or for bioenergy becomes a challenge reliant on regulatory and policy frameworks.