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17541. 题目: Antibiotics in mariculture systems: A review of occurrence, environmental behavior, and ecological effects
文章编号: N21111903
期刊: Environmental Pollution
作者: Xiaotong Wang, Yufei Lin, Yang Zheng, Fanping Meng
更新时间: 2021-11-19
摘要: Antibiotics are widely applied to prevent and treat diseases occurred in mariculture. The often-open nature of mariculture production systems has led to antibiotic residue accumulation in the culturing and adjacent environments, which can adversely affect aquatic ecosystems, and even human. This review summarizes the occurrence, environmental behavior, and ecological effects of antibiotics in mariculture systems based on peer-reviewed papers. Forty-five different antibiotics (categorized into ten groups) have been detected in mariculture systems around the world, which is far greater than the number officially allowed. Indiscriminate use of antibiotics is relatively high among major producing countries in Asia, which highlights the need for stricter enforcement of regulations and policies and effective antibiotic removal methods. Compared with other environmental systems, some environmental characteristics of mariculture systems, such as high salinity and dissolved organic matter (DOM) content, can affect the migration and transformation processes of antibiotics. Residues of antibiotics induce the formation of antibiotic resistance genes (ARGs). Antibiotics and ARGs alter microbial communities and biogeochemical cycles, as well as posing threats to marine organisms and human health. This review may provide a valuable summary of the effects of antibiotics on mariculture systems.

17542. 题目: Climatic controls on soil carbon accumulation and loss in a dryland ecosystem
文章编号: N21111902
期刊: Journal of Geophysical Research: Biogeosciences
作者: Bonnie G. Waring, Kenneth R. Smith, Edmund E. Grote, Armin Howell, Robin Reibold, Colin L. Tucker, Sasha C. Reed
更新时间: 2021-11-19
摘要: Arid and semiarid ecosystems drive year-to-year variability in the strength of the terrestrial carbon (C) sink, yet there is uncertainty about how soil C gains and losses contribute to this variation. To address this knowledge gap, we embedded C-depleted soil mesocosms, containing litter or biocrust C inputs, within an in situ dryland ecosystem warming experiment. Over the course of one year, changes in microbial biomass and total soil organic C pools were monitored alongside hourly measurements of soil CO2 flux. We also developed a biogeochemical model to explore the mechanisms that gave rise to observed soil C dynamics. Field data and model simulations demonstrated that water exerted much stronger control on soil biogeochemistry than temperature, with precipitation events triggering large CO2 pulses and transport of litter- and biocrust-derived C into the soil profile. We expected leaching of organic matter would result in steady accumulation of C within the mineral soil over time. Instead, the size of the total organic C pool fluctuated throughout the year, largely in response to microbial growth: increases in the size of microbial biomass were negatively correlated with the quantity of C residing in the top 2 cm, where most biogeochemical changes were observed. Our data and models suggest that microbial responses to precipitation events trigger rapid metabolism of dissolved organic C inputs, which strongly limit accumulation of autotroph-derived C belowground. Accordingly, changes in the magnitude and/or frequency of precipitation events in this dryland ecosystem could have profound impacts on the strength of the soil C sink.

17543. 题目: Evaluation of membrane tailored with biocompatible halloysite‒polyaniline nanomaterial for efficient removal of carcinogenic disinfection by‒products precursor from water
文章编号: N21111901
期刊: Environmental Research
作者: S. Elakkiya, G. Arthanareeswaran
更新时间: 2021-11-19
摘要: Humic acid (HA) is the main component of natural organic matter that generates carcinogenic by‒products during disinfection and its removal from water resources is challenging. Biocompatible halloysite (HNTs) nanomaterial decorated with polyaniline (HNTs‒PANI) was synthesized via polymerization technique. HNTs‒PANI was added to prepare polyethersulfone mixed matrix membranes (MMMs). The influence of HNTs‒PANI concentration on HA removal efficiency was studied by varying the HNTs‒PANI (0.5, 1 and 1.5 wt%). The characterization studies of MMMs revealed that the addition of HNTs‒PANI improved the morphology of the membranes, surface properties, chemical stability and thermal property. The amine and hydroxyl groups within the MMMs improved the membrane wettability. The addition of HNTs‒PANI within the MMMs had significantly enhanced the pure water flux and HA filtration. YHP2 MMM with 1 wt% of HNTs‒PANI demonstrated sieving coefficient of 0.10 and the highest HA removal efficiency of 91% greater than the neat PES membrane. Furthermore, the antifouling property of the MMMs was studied using HA as foulant. 1 wt% of HNTs‒PANI added MMM showed a high flux recovery ratio (94.9%) with low total fouling of 12% and low irreversible fouling of 5%, respectively. Thus, HNTs‒PANI was an efficient nanomaterial for enhancing the pure water flux, removal efficiency and antifouling property for the treatment of water contaminated with HA.

17544. 题目: Recalcitrant compounds formation, their toxicity, and mitigation: Key issues in biomass pretreatment and anaerobic digestion
文章编号: N21111818
期刊: Chemosphere
作者: Gowtham Balasundaram, Rajesh Banu, Sunita Varjani, A.A. Kazmi, Vinay Kumar Tyagi
更新时间: 2021-11-18
摘要: Increasing energy demands and environmental issues have stressed the importance of sustainable methods of energy production. Anaerobic digestion (AD) of the biodegradable waste, i.e., agricultural residues, organic fraction of municipal solid waste (OFMSW), sewage sludge, etc., results in the production of biogas, which is a sustainable and cost feasible technique that reduces the dependence on fossil fuels and also overcomes the problems associated with biomass waste management. To solubilize the organic matter and enhance the susceptibility of hardly biodegradable fraction (i.e., lignocellulosic) for hydrolysis and increase methane production, several pretreatments, including physical, chemical, biological, and hybrid methods have been studied. However, these pretreatment methods under specific operating conditions result in the formation of recalcitrant compounds, such as sugars (xylose, Xylo-oligomers), organic acids (acetic, formic, levulinic acids), and lignin derivatives (poly and mono-phenolic compounds), causing significant inhibitory effects on anaerobic digestion. During the scaling up of these techniques from laboratory to industrial level, the focus on managing inhibitory compounds formed during pretreatment is envisaged to increase because of the need to use recalcitrant feedstocks in anaerobic digestion to increase biogas productivity. Therefore, it is crucial to understand the production mechanism of inhibitory compounds during pretreatment and work out the possible detoxification methods to improve anaerobic digestion. This paper critically reviews the earlier works based on the formation of recalcitrant compounds during feedstocks pretreatment under variable conditions, and their detrimental effects on process performance. The technologies to mitigate recalcitrant toxicity are also comprehensively discussed.

17545. 题目: Evaluating the impact of rice husk on successions of bacterial and fungal communities during cow manure composting
文章编号: N21111817
期刊: Environmental Technology & Innovation
作者: Haiyan Duan, Minghua Ji, Ai Chen, Baoguo Zhang, Jiping Shi, Li Liu, Xiang Li, Junsong Sun
更新时间: 2021-11-18
摘要: Although rice husk (RH) has been used as a compost additive, the microbes present in RH are not well understood. In this study, we explored the physicochemical parameters, the microbial population and functional succession to better understand how different levels (T0: 0; T1: 20%; T2: 30%) of RH affected the performance of cow manure composting. Higher thermophilic temperatures (70 °C) and higher-quality compost with respect to pH, the C/N ratio, particle-size distribution and other characteristics were obtained with the addition of 20% RH. The total nitrogen and germination index (GI) of the final product (T1) increased by 48% and 175%, respectively, compared to those of T0. Moreover, fluorescence spectra indicated that the degradation of protein-type groups and the formation of humic substances increased in T1. Microbial analyses indicated that interactions between bacterial communities were also strengthened in T1. We also found that Sphaerobacter and Myceliophthora were the unique and dominant thermophilic genera of bacteria and fungi, respectively, in RH-supplemented compost. Carbohydrate metabolism and amino acid metabolism were the main metabolic pathways, and saprotrophs represented the dominant fungal trophic mode in the composting process. In T1, bacteria were mainly affected by temperature and pH, while fungi were more affected by moisture. This study found a suitable RH dosage for composting and provides a microbiological basis for RH as a compost additive.

17546. 题目: Biofilm formation as a method of improved treatment during anaerobic digestion of organic matter for biogas recovery
文章编号: N21111816
期刊: Bioresource Technology
作者: Roent Dune A. Cayetano, Gi-Beom Kim, Jungsu Park, Yung-Hun Yang, Byong-Hun Jeon, Min Jang, Sang-Hyoun Kim
更新时间: 2021-11-18
摘要: The efficiency of anaerobic digestion could be increased by promoting microbial retention through biofilm development. The inclusion of certain types of biofilm carriers has differentiated existing AD biofilm reactors through their respective mode of biofilm growth. Bacteria and archaea engaged in methanogenesis during anaerobic processes potentially build biofilms by adhering or attaching to biofilm carriers. Meta-analyzed results depicted varying degrees of biogas enhancement within AD biofilm reactors. Furthermore, different carrier materials highly induced the dynamicity of the dominant microbial population in each system. It is suggested that the promotion of surface contact and improvement of interspecies electron transport have greatly impacted the treatment results. Modern spectroscopy techniques have been and will continue to give essential information regarding biofilm’s composition and structural organization which can be useful in elucidating the added function of this special layer of microbial cells.

17547. 题目: Biochar and nitrogen fertilizer co-application changed SOC content and fraction composition in Huang-Huai-Hai plain, China
文章编号: N21111815
期刊: Chemosphere
作者: Linlin Dong, Xiao Yang, Linlin Shi, Yuan Shen, Lingqing Wang, Jidong Wang, Chuanzhe Li, Haidong Zhang
更新时间: 2021-11-18
摘要: Biochar can significantly enhance soil organic carbon (SOC) and crop yield, and it is therefore the preferred material for soil improvement in medium-low yield fields. In this study, a field experiment was designed to explore the impacts of biochar application on SOC content and fraction composition. Results indicated that incorporation of biochar into soil increased the SOC content by 26.9%–65.3% in the surface layer (0–10 cm) and 30.3%–63.0% in the subsurface layer (10–20 cm) of soil, while water-soluble organic carbon (WSOC) of the two layers was increased by 2.2–40.0% and 2.3–39.8%, respectively. Microbial biomass carbon decreased under conventional nitrogen treatments and increased with biochar addition under increased nitrogen application. The C:N value increased with biochar application, while the water-soluble C:N value of soil applied with 30 t ha−1 biochar was lower than that of soil applied with 15 t ha−1 biochar, both in the two tested soil layers. Wheat yield is evidently correlated with SOC, with the correlation coefficients of 0.919 and 0.952 in the surface and subsurface soil layers (P < 0.01), respectively. Particularly, increasing fulvic and humic acid-like compounds of WSOC promoted the bioavailability of nutrient elements, thereby increasing the crop yields. Therefore, biochar application is an effective means to fertilize middle-low yield soils through increasing SOC sequestration and nutrient reserves, or adjusting soil C:N value to a proper range, thereby reducing nutrient loss and increasing wheat yield.

17548. 题目: Wastewater post-coagulation sludge recycled as a multifunctional adsorbent via pyrolysis enhanced in carbon dioxide (CO2)
文章编号: N21111814
期刊: Chemosphere
作者: Mengyue Wang, Guoshuai Liu, Xiuheng Wang
更新时间: 2021-11-18
摘要: Massive wastewater post-coagulation sludge (WPCS) generated from the tertiary treatment facilities has been regarded as an environmentally burdensome waste. Herein, to take advantage of the abundant amounts of Al/Fe (hydr)oxides, the WPCS was converted into functional char via pyrolysis under CO2 and N2 atmosphere. The higher organic matter content and porous structure of WPCS than drinking water treatment sludge made it a more suitable precursor for biochar and adsorbent production. CO2 expedited the thermolysis of the organics in WPCS and the Fe (hydr)oxides in WPCS further decreased the temperature of CO2-mediated reaction. Therefore, the corresponding products outcompeted the chars in N2, achieving ∼37% higher specific surface area, stronger aromaticity and more amorphous Al and Fe contents of 201.19 ± 2.25 and 27.03 ± 0.56 mg g−1, accompanied by more loss of surface functional groups like carboxyl and hydroxyl. Accordingly, WPCS chars under CO2 showed superior performance for removing phosphate (15.58 ± 0.19 mg g−1), along with the adsorption of heavy metal (37.17 ± 1.25 mg g−1 of Pb (II)) and dye (14.45 ± 0.11 mg g−1 of methylene blue). In sum, this study proposes a win–win strategy to convert coagulation sludges into resources and a new candidate for multifunctional adsorbent production.

17549. 题目: Decay by ectomycorrhizal fungi couples soil organic matter to nitrogen availability
文章编号: N21111813
期刊: Ecology Letters
作者: William A. Argiroff, Donald R. Zak, Peter T. Pellitier, Rima A. Upchurch, Julia P. Belke
更新时间: 2021-11-18
摘要: Interactions between soil nitrogen (N) availability, fungal community composition, and soil organic matter (SOM) regulate soil carbon (C) dynamics in many forest ecosystems, but context dependency in these relationships has precluded general predictive theory. We found that ectomycorrhizal (ECM) fungi with peroxidases decreased with increasing inorganic N availability across a natural inorganic N gradient in northern temperate forests, whereas ligninolytic fungal saprotrophs exhibited no response. Lignin-derived SOM and soil C were negatively correlated with ECM fungi with peroxidases and were positively correlated with inorganic N availability, suggesting decay of lignin-derived SOM by these ECM fungi reduced soil C storage. The correlations we observed link SOM decay in temperate forests to tradeoffs in tree N nutrition and ECM composition, and we propose SOM varies along a single continuum across temperate and boreal ecosystems depending upon how tree allocation to functionally distinct ECM taxa and environmental stress covary with soil N availability.

17550. 题目: Multi-faceted influences of biochar addition on swine manure digestion under tetracycline antibiotic pressure
文章编号: N21111812
期刊: Bioresource Technology
作者: Gaojun Wang, Yuxi Chu, Jinglin Zhu, Li Sheng, Guohao Liu, Yao Xing, Peng Fu, Qian Li, Rong Chen
更新时间: 2021-11-18
摘要: This study explored the influence of biochar (BC) on anaerobic digestion (AD) of swine manure under various tetracycline (TC) pressures. It was found that both low (0.5 mg/L) and high (50 mg/L) TC pressures inhibited AD performance, while BC mitigated it in multi-facets. Under high TC pressure, BC accelerated syntrophic methanogenesis by boosting direct interspecies electron transfer pathway. The TC removal efficiencies were enhanced by 24.3-158.2% with BC assistance, which were attributed to the enhanced biological degradation rather than BC’s physiochemical adsorption. Moreover, BC possibly acted as a protective role to alleviate intensive extracellular polymeric substances secretion under TC pressures. Integrated microbial community, metabolic function predicting, and antibiotic resistance genes (ARG) analysis revealed that BC addition not only enriched Anaerolineceae, which likely responsible for the 24.2-41.9% higher level expression of organics metabolic pathways and xenobiotics biodegradation, but also reduced ARG abundance by controlling the potential ARG host (Firmicutes) proliferation.

17551. 题目: Photochemistry of dissolved organic matter in water from the Pearl River (China): Seasonal patterns and predictive modelling
文章编号: N21111811
期刊: Water Research
作者: Zhiyang Liao, Yi Wang, Kunting Xie, Nangeng Xie, Xixi Cai, Lihua Zhou, Yong Yuan
更新时间: 2021-11-18
摘要: Photochemical properties of dissolved organic matter (DOM) vary widely in natural and engineered water systems due to the different dominant compositions. However, seasonal patterns of DOM photochemical properties in urban rivers remain unclear. In this study, two seasons (wet and dry) of water samples were collected from eleven sites throughout the Pearl River (China) to investigate the spatiotemporal variability of DOM optical and photochemical properties. The optical properties of DOM in the Pearl River were characterized by UV-vis and fluorescence spectroscopies, which showed the substantial decrease in absorption coefficient and fluorescence intensity and increase in absorbance ratio (E2/E3) and specific absorption coefficient (SUVA) from the wet to dry season. The photochemical properties in terms of the apparent quantum yields of 3DOM*, 1O2 and •OH from DOM (Φ3DOM*, Φ1O2 and Φ•OH, DOM) under illumination also displayed a significant decrease from the wet to the dry season. Spearman's rank correlation analysis revealed the strongest relationships between Φ3DOM*, Φ1O2 and Φ•OH, DOM and the relative abundance of microbial humic-like component (C2%) derived from parallel factor analysis (PARAFAC). Partial least squares regression (PLSR) modelling exhibited an excellent prediction strength for steady-state concentrations of 1O2 ([1O2]ss) and •OH ([•OH]ss) with adjusted R2 values of 0.85 and 0.91, respectively, by using DOC concentration ([DOC]), optical properties, nitrate and nitrite concentrations as the response variables. In addition, the model identified that the Fmax of humic-like component C4 (Fmax-C4) was the most effective predictor among the used response variables. This study provides an approach to describe and predict the seasonal patterns of DOM photochemical properties in urbanized rivers, offering a good understanding of the formation mechanism of reactive species from river DOM.

17552. 题目: Spatial prediction of soil organic carbon stocks in an arid rangeland using machine learning algorithms
文章编号: N21111810
期刊: Environmental Monitoring and Assessment
作者: Mahmood Rostaminia, Asghar Rahmani, Sayed Roholla Mousavi, Rohullah Taghizadeh-Mehrjardi, Ziba Maghsodi
更新时间: 2021-11-18
摘要: Assessing the role of machine learning (ML) models concerning environmental predictors on spatial variation of soil organic carbon stocks (SOCS) in arid rangelands is very necessary. This study was conducted to explore the variability of surface SOCS in rangeland in the west of Iran using ML approaches. A number of 33 environmental predictors derived from Sentinel-2B and DEM were used. The optimal soil sampling (n = 80) position was determined by Latin hypercube sampling (cLHS) method. Robust and popular random Forest (RF), cubist (CB) along with random forest-ordinary kriging (RF-OK), and cubist-ordinary kriging (CB-OK) hybrid ML models were applied to the prediction of SOCS. Ten-fold CV was implemented for modeling performance and uncertainty map. According to data analysis, the maximum, minimum, and average values of SOCS are 44.50, 10.50, and 20.50 (ton. ha-1) at the surface depth (0-30 cm), respectively. In general, normalized and standardized height covariates had a higher effect related to other predictors. On the other hand, two remote sensing (RS) indices, including salinity ratio (salinity) and GNDVI index, had a better impact on SOCS variability. The external validation of model performance indicated that RF-OK with (R2 = 0.75, RMSE = 6.33 ton. ha-1) with the high and low uncertainty range (3.33-9.50 ton. ha-1) was the outperformed ML model in compare with other models as RF (R2 = 0.65, RMSE = 7.38 ton. ha-1), CB-OK (R2 = 0.56, RMSE = 9.22 ton. ha-1), and CB (R2 = 0.33, RMSE = 10.42 ton. ha-1). In general, the hybrid models improved the accuracy of RF and CB with increased 0.11 until 0.23 of R2, and 1.05 to 1.2 (ton. ha-1) decreased RMSE of model's prediction. Hence, we conclude that the topographic attributes (especially normalized and standardized height) were the most critical factors in controlling surface SOCS in arid rangelands when combining with robust RF ML model, and optimized soil sampling methods like RF-cLHS can prepare acceptable soil properties maps.

17553. 题目: Desorption of micropollutant from superfine and normal powdered activated carbon in submerged-membrane system due to influent concentration change in the presence of natural organic matter: experiments and two-component branched-pore kinetic model
文章编号: N21111809
期刊: Water Research
作者: Long Pan, Akiko Nakayama, Yoshihiko Matsui, Taku Matsushita, Nobutaka Shirasaki
更新时间: 2021-11-18
摘要: Submerged-membrane hybrid systems (SMHSs) that combine membrane filtration with powdered activated carbon (PAC) take advantage of PAC's ability to adsorb and remove contaminants dissolved in water. However, the risk of contaminant desorption due to temporal changes in the influent concentration of the contaminant has not been thoroughly explored. In this study, we used a SMHS with conventionally-sized PAC or superfine PAC (SPAC) to remove 2-methylisoborneol (MIB), a representative micropollutant, from water containing natural organic matter (NOM), with the goal of elucidating adsorption–desorption phenomena in the SMHS. We found that 20–40% of the MIB that adsorbed on PAC and SPAC while the influent was contaminated with MIB (6 h, contamination period) desorbed to the liquid phase within 6 h from the time that the MIB-containing influent was replaced by MIB-free influent (no-contamination period). The percentage of desorption during the no-contamination period increased with increasing MIB breakthrough concentration during the contamination period. These findings indicate that the PAC/SPAC in the SMHS should be replaced while the breakthrough concentration is low, not only to keep a high removal rate but also to decrease the desorption risk. SPAC is fast in removal by adsorption, but it is also fast in release by desorption. SPAC (median diameter: 0.94 µm) showed almost the same adsorption-desorption kinetics as PAC (12.1 µm) of a double dose. A two-component branched-pore diffusion model combined with an IAST (ideal adsorbed solution theory)–Freundlich isotherm was used to describe and analyze the adsorption–desorption of MIB. The diffusivity of MIB molecules in the pores of the activated carbon particles decreased markedly in a short period of time. This decrease, which was attributed to fouling of the activated carbon in the SMHS by coagulant-treated water containing NOM, not only reduced the rate of MIB removal during the contamination period but also hindered the rate of MIB desorption during the no-contamination period and thus prevented the effluent MIB concentration from becoming high. On the other hand, coagulation did not change the concentration of NOM that competes with MIB for adsorption sites.

17554. 题目: Interannual variation of settling particles reflects upper‐ocean circulation in the southern Chukchi Borderland, 2010‐2014
文章编号: N21111808
期刊: Journal of Geophysical Research: Oceans
作者: Jonaotaro Onodera, Eiji Watanabe, Motoyo Itoh, Naomi Harada, Makio C. Honda, Anders Tengberg, Yuichiro Tanaka, Takashi Kikuchi
更新时间: 2021-11-18
摘要: Time series monitoring of hydrography and marine settling particles supplies a large amount of information regarding the marine lower-trophic ecosystem with respect to the changing Arctic Ocean. To investigate the interannual relationship between the settling particles and hydrographic conditions of the western Arctic Ocean, bottom-tethered sediment trap moorings were deployed at the Northwind Abyssal Plain (NAP) from October 2010 to September 2014 and at the Chukchi Abyssal Plain (CAP) from October 2012 to September 2013 to the east and west of the Chukchi Borderland. The settling particles at both stations contained a significant amount of lithogenic matter, with biogenic particles being a lateral advection of shelf materials from shelf to basin. The many peaks of settling particle fluxes at NAP in 2013-2014 corresponded to the hydrographic events of passing oceanic eddies over the station, in addition to seasonal biological production. The settling particle flux at CAP remarkably increased when Pacific-origin water advected over the northern shelf of the Chukchi Sea in March-April 2013. Additionally, abundant gelatinous matter was found at NAP and CAP in July-September 2011 and 2014 and in July-August 2013, respectively. The settling flux data of particulate organic matter and the mole ratio and stable isotope ratios of particulate organic carbon and nitrogen reflected the changes in the composition of trapped plankton assemblages under various hydrographic conditions over the course of the four years of the study.

17555. 题目: Biochar nanosphere- and covalent organic framework nanosphere-functionalized titanium dioxide nanorod arrays on carbon fibers for solid-phase microextraction of organic pollutants
文章编号: N21111807
期刊: Chemical Engineering Journal
作者: Mingxia Sun, Juanjuan Feng, Jiaqing Feng, Haili Sun, Yang Feng, Xiangping Ji, Chunying Li, Sen Han, Min Sun
更新时间: 2021-11-18
摘要: To improve the extraction efficiency of carbon fibers (CFs) toward organic pollutants, TiO2 nanorod arrays (NARs) were grown in situ on CFs. Subsequently, biochar nanospheres and covalent organic framework nanospheres were separately introduced to functionalize the NARs. A sequence of materials was produced by regulating the reactant concentrations and characterized using a scanning electron microscope, an X-ray photoelectron spectrometer, an X-ray diffractometer, a Raman spectrometer, and a specific surface area analyzer. The materials were then deposited into separate poly(etheretherketone) tubes for in-tube solid-phase microextraction (IT-SPME). These tubes were evaluated with different types of organic pollutants (polycyclic aromatic hydrocarbons (PAHs), estrogens, bisphenols, and phthalate esters) using a combination of high-performance liquid chromatography and IT-SPME, and they exhibited diverse extraction performance. The extraction mechanism of each material is carefully discussed, and the structure–performance relationship is also summarized based on the chemical structures and extraction properties of the materials. The most efficient extraction materials for different analytes were discovered and used to develop analytical methods. Three online methods were used to sensitively detect PAHs, estrogens, and bisphenols in real water samples, respectively. Satisfactory results were obtained, including enrichment factors up to 6784, detection limits as low as 0.001 μg L−1, linear ranges of 0.003–15.0 μg L−1, and relative standard deviations ranging from 0.2% to 15.2%. The results indicate that these methods have some advantages over previous material-based methods.

17556. 题目: Biochar and nitrogen fertilizer increase Glomus synergism and abundance and promote Trifolium pratense growth while inhibiting pollutant accumulation
文章编号: N21111806
期刊: Ecological Indicators
作者: Lu Chen, Wanlin Li, Yan Xiao
更新时间: 2021-11-18
摘要: We examined the effects of nitrate nitrogen fertilizer (N), biochar (BC) and arbuscular mycorrhizal fungi (AMF) on Trifolium pratense mycorrhizal colonization, dry mass, nutrient and pollutant accumulation and soil AMF community, aiming to determine a potential approach that is beneficial to clover growth and AMF community under contaminated environment. Result showed that soil pH increased from 6.88 to 7.01 in the presence of N in combination BC treatments. Compared to control, N in combination BC treatments significantly decreased DTPA-Zn, Pb, Cd, As and Cu concentrations, and the average reduction for DTPA-Zn, Pb, Cd, As and Cu concentration by 53.2, 52.5, 48.8, 44.5 and 45.5%, respectively. Root colonization, shoot and root dry masses were increased when receiving both N and BC. On average, the shoot P, Zn, Pb, Cd and As levels were reduced by 39.7, 62.4, 86.7, 84.6 and 87.8% when receiving both N and BC and simultaneously the root Cd and Zn concentrations were reduced by 64.9 and 55.8%, respectively. DTPA-extractable Cd, Zn and Pb were positively correlated to shoot Zn, Pb and Cd concentrations as well as root Zn and Cd concentrations but negatively correlated with pH. Moreover, Glomus species were the soil major AMF present with all treatments. The combination N and BC treatments increased Glomus abundance but did not affect overall AMF diversity. Soil pH, DTPA-Cd, Zn, Pb and Cu had greater effect on AMF community structure as assessed by redundancy analysis (RDA). Glomus abundance was positively related to pH, root colonization, shoot and root dry mass and negatively related to DTPA-Cd, Zn, Pb and Cu. A network analysis indicated that BC and N addition promoted synergistic interactions among Glomus species. Our results demonstrated that the N in combination BC treatments can promote plant growth while decreasing pollutant accumulation in shoot and root, and the N and BC addition can increase Glomus abundance and their synergistic interactions under multi-contaminated soil.

17557. 题目: Overcoming biochar limitations to remediate pentachlorophenol in soil by modifying its electrochemical properties
文章编号: N21111805
期刊: Journal of Hazardous Materials
作者: Francisco J. Chacón, Maria L. Cayuela, Harald Cederlund, Miguel A. Sánchez-Monedero
更新时间: 2021-11-18
摘要: In this study, we produced modified biochars with enhanced electrochemical properties to increase PCP remediation in soil. Although all biochars enhanced PCP remediation in aerobic conditions, only a few did in anaerobic soil. The most successful modifications were (i) the preloading of biomass with 10% w/w FeCl3, to obtain a biochar rich in redox-active metals (B-Fe); (ii) the oxidation of a conductive biochar pyrolyzed at 1000 ºC with 0.025M KMnO4, to produce a biochar with both moderate conductivity and redox capacity (B-1000-KMnO4); and (iii) KMnO4 oxidation of an amorphous biochar pyrolyzed at 400 ºC to obtain a biochar with very high redox capacity (B-KMnO4). B-Fe reduced extractable PCP to almost zero after 50 days in both incubations, but showed slow kinetics of remediation in aerobic soil. B-1000-KMnO4 had the highest rate of remediation under aerobic conditions, but no significant effect under anaerobic conditions. B-KMnO4, however, presented high rates of remediation and high removal of extractable PCP under both conditions, which made it the recommended modification strategy for increased PCP remediation. We found that the degree of remediation primarily depends on the redox capacity, while the rate of remediation was determined by both the conductivity and redox capacity of biochar.

17558. 题目: Synergistic activation of sulfite for As(III) oxidation by basic copper(II) carbonate in homogeneous and heterogeneous processes at near-neutral conditions
文章编号: N21111804
期刊: Chemical Engineering Journal
作者: Zizheng Liu, Jiawei Liu, Haike Yang, Jingyi Guo, Yiqun Chen, Qing Shao, Shuxian Gao, Liting Luo
更新时间: 2021-11-18
摘要: Arsenic is categorized as a class I carcinogen due to its strong biological toxicity. In this study, a novel treatment process with Cu2(OH)2CO3 as catalyst is proposed, whereby As(III) in water is oxidized by activating sulfite to generate SO4•− and SO5•− radicals. Under conditions of [Cu2(OH)2CO3]0 = 0.01 g·L−1, [sulfite]0 = 0.3 mmol·L−1, and initial pH 8.0, 94% of As(III) was converted into As(V) within 20 min, whereby dissolved oxygen had a pivotal impact on the reaction. However, HCO3−, humic acid, and fulvic acid all significantly inhibited the oxidation. Heterogeneous electron transfer on the catalyst surface and homogeneous dissolved Cu2+ jointly activated sulfite in the Cu2(OH)2CO3/sulfite system, with the heterogeneous process predominating. Density functional theory (DFT) calculations disclose a dominate physical adsorption of sulfite on Cu2(OH)2CO3 surface with 1.74 electrons transferred. More than 90% of As(III) was still oxidized after recycling the material five times, indicating excellent reusability. Overall, it shows good potential for application in the removal of As(III) from real water samples.

17559. 题目: Different dissolved organic matters regulate the bioavailability of heavy metals and rhizosphere microbial activity in a plant-wetland soil system
文章编号: N21111803
期刊: Journal of Environmental Chemical Engineering
作者: Yuanhang Li, Xiaofeng Gong, Jieqian Xiong, Yuheng Sun, Yao Shu, Danni Niu, Yuan Lin, Li Wu, Ru Zhang
更新时间: 2021-11-18
摘要: Dissolved organic matter (DOM) and hydrologic conditions significantly influences the migration and transformation of heavy metals, especially in wetland soil. However, there still remains challenge in understanding how the DOM from different sources regulates the bioavailability of heavy metals, enzyme activity and microbial activity. In this study, we investigated the effects of natural DOM (NDOM, extraction of Carex cinerascens) and artificial DOM (Humic acids, HA) on microbial community and bioavailability of Cu and Pb in wetland soils of Poyang Lake under wetted and flooded conditions. The results demonstrated that the pH increased from 5.5 to 6.4 while Eh decreased from 95.8 to 31.6mV to maximum extent after applying HA under flooded condition. Although planting C. cinerascens improved the soil quality under the stress of Cu and Pb, the use of HA restrained this effect except for Pb under wetted condition, demonstrating the intake of exogenous DOM increased the bioavailability of metals under flooded condition. However, the activities of catalase and urease in soil were markedly enhanced due to the implication of DOM, which increased more under the wetted condition as compared to the flooded condition. Similar phenomenon was found in chlorophyll. In addition, microbial diversity and community could be promoted by the application of HA. Diethylenetriamine pentaacetic acid -Cu (DTPA-Cu), pH and flooded condition might significantly influence the bacterial composition. Therefore, this research presents valuable theoretical basis for remediation of heavy metals and effects of DOM and hydrologic condition on microorganism in plant-wetland soil system.

17560. 题目: Mesoporous and adsorption behavior of algal biochar prepared via sequential hydrothermal carbonization and ZnCl2 activation
文章编号: N21111802
期刊: Bioresource Technology
作者: Thanh-Binh Nguyen, Quoc-Minh Truong, Chiu-Wen Chen, Ruey-an Doong, Wei-Hsin Chen, Cheng-Di Dong
更新时间: 2021-11-18
摘要: In this study, biochar derived from brown algal Ascophyllum nodosum was synthesized through hydrothermal carbonization (HTC) coupling with ZnCl2 chemical activation and applied as a sustainable adsorbent for antibiotic removal from water exemplified by ciprofloxacin (CIP). Various surface analysis techniques such as Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and zeta potential were used to clarify the surface properties of prepared biochars. The adsorption performance of biochars was investigated using batch adsorption experiments with a variety of parameters (initial pH, ionic types, temperature and water matrixes). The application of prepared biochar in CIP removal showed a good result of adsorption capacity (150 − 400 mg g-1) in different conditions. Overall, algal biochars, as a product recycled from biowaste, demonstrated a novel and promising adsorbent for effective and sustainable method for removal of antibiotics from water.