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181. 题目: Simultaneous reclaiming phosphate and ammonium from aqueous solutions by calcium alginate-biochar composite: Sorption performance and governing mechanisms
文章编号: N21090507
期刊: Chemical Engineering Journal
作者: Qianwei Feng, Miao Chen, Pan Wu, Xueyang Zhang, Shengsen Wang, Zebin Yu, Bing Wang
更新时间: 2021-09-05
摘要: The eutrophication of aquatic environments has become one of the major environmental problems. To reduce nitrogen and phosphorus in water, industrial waste (distillers grains), agricultural waste (rice straw), and an invasive plant (Eupatorium adenophorum) were used to prepare ball-milled biochar (BMB), and further synthesize calcium alginate-biochar composite (CA-MB) for simultaneous adsorption of phosphate and ammonium. The scanning electron microscope (SEM), Fourier infrared spectroscopy (FTIR), Zeta potential, and BET specific surface area (SSA) analyzer were used to characterize the physicochemical properties of CA-MB. The effects of different conditions (pyrolysis temperature, dosage, solution pH, and coexisting ions) on the adsorption performance were studied. Combined with adsorption kinetics and isotherms, the co-adsorption performance and governing mechanisms of phosphate and ammonium onto CA-MB were explored. The results showed that the CA-MB prepared from distillers grains, rice straw and Eupatorium adenophorum had better adsorption performances on phosphate and ammonium at the pyrolysis temperatures of 600°C (CA-MWB600), 300°C (CA-MRB300), and 600°C (CA-MEB600), respectively. The maximum adsorption capacities of CA-MWB600, CA-MRB300, and CA-MEB600 for phosphate and ammonium estimated with Langmuir isotherm model were 24.1, 31.8, 24.0 mg g−1 and 12.27, 10.15, 9.90 mg g−1, respectively. The main adsorption mechanisms for phosphate were electrostatic attraction, surface precipitation, and ligand exchange, while for ammonium were ion exchange and electrostatic attraction. The retention capacity of CA-MB for phosphate was better than ammonium. This study indicates that CA-MB can be used as an effective adsorbent for simultaneous recovery of phosphate and ammonium from water.

182. 题目: When dewatered swine manure-derived biochar meets swine wastewater in anaerobic digestion: A win-win scenario towards highly efficient energy recovery and antibiotic resistance genes attenuation for swine manure management
文章编号: N21090506
期刊: Science of The Total Environment
作者: Gaojun Wang, Jinglin Zhu, Yao Xing, Yanan Yin, Yu Li, Qian Li, Rong Chen
更新时间: 2021-09-05
摘要: This work explored the feasibility of dewatered swine manure-derived biochar (DSMB) as an additive to facilitate anaerobic digestion (AD) of swine wastewater for energy recovery and antibiotic resistance genes (ARG) attenuation enhancements. With 20 g/L DSMB assistance, the methanogenic lag time of swine wastewater was shortened by 17.4-21.1%, and the maximum CH4 production rate increased from 40.8 mL/d to 48.3-50.5 mL/d, among which DSMB prepared under 300 °C exhibited a better performance than that prepared under 500 °C and 700 °C. Integrated analysis of DSMB electrochemical properties, microbial electron transfer system activity, and microbial community succession revealed the potential of DSMB-300 to act as redox-active electron transfer mediators between syntrophic microbes to accelerate syntrophic methanogenesis by potential direct interspecies electron transfer. Meanwhile, DSMB preparation by pyrolysis dramatically reduced ARG abundance by almost 4 logs. Adding DSMB into AD not only strengthened the attenuation efficiency of ARG in the original swine wastewater, but also effectively controlled the potential risk of horizontal gene transfer by mitigating 74.8% of the mobile gene elements abundance. Accordingly, we proposed a win-win scenario for bio-waste management in swine farms, highlighting the more advanced energy recovery and ARG attenuation compared to the current status.

183. 题目: Soil nitrogen and climate drive the positive effect of biological soil crusts on soil organic carbon sequestration in drylands: A Meta-analysis
文章编号: N21090505
期刊: Science of The Total Environment
作者: Hengkang Xu, Yingjun Zhang, Xinqing Shao, Nan Liu
更新时间: 2021-09-05
摘要: Biological soil crusts (BSCs), known as ecological engineers, play an important role in soil organic carbon (SOC) sequestration in dryland ecosystems. Although numerous individual studies had been conducted, the global patterns of the changes in SOC concentration following BSCs establishment remain unclear. In this study, we performed a comprehensive meta-analysis of 184 independent observations at 47 sites to quantify the responses of SOC and other soil variables to BSCs establishment and identify the underlying mechanisms. Our results showed that BSCs generally increased SOC by 70.9% compared to the controls (uncrusted soil), and the positive effects of BSCs on SOC in deserts (120.3%) were stronger than those in grasslands (32.7%). Mosses and lichens had a stronger positive effect on SOC than algae crusts (67.5%, 82.8%, and 58.2% respectively). Mixed crusts accumulated more SOC (181.6%) than single (moss, lichen and algae) crusts. The presence of BSCs considerably increased total nitrogen (TN) (+80.7%), total phosphorus (TP) (+20.3%), available N (+62.7%), and available P (+14.3%). Significant relationships were observed among the effect size of SOC and climate and soil N and P in both desert and grassland. The random forest analysis showed that TN could be considered as a determinant of the concentration of SOC, followed by climate (P < 0.01). Our study shows that the capacity of the BSCs to fix and store C could be regulated by soil N and P dynamics, indicating a major finding opening new ways to promote soil recovery and formation. Our findings highlight the remarkable contribution of mixed crusts to soil C pools; this contribution needs to be incorporated into regional and global models to predict the effects of human disturbance on drylands worldwide and for assessing the soil C budget.

184. 题目: Biochar/iron oxide composite as an efficient peroxymonosulfate catalyst for the degradation of model naphthenic acids compounds
文章编号: N21090504
期刊: Chemical Engineering Journal
作者: Junying Song, Zuo Tong How, Zhanbin Huang, Mohamed Gamal El-Din
更新时间: 2021-09-05
摘要: Naphthenic acids (NAs) are a mixture of aliphatic and alicyclic carboxylic acids which are persistent in the environment. In this study, a sludge-based biochar/iron oxide (B-FeOx) catalyst with 3D flower-like shaped structure was prepared through a facile hydrothermal method. For the first time, the B-FeOx catalyst was employed to activate peroxymonosulfate (PMS) for the removal of two model NA compounds (1-adamantanecarboxylic acid (ACA) and 4-methylheptanoic acid) at pH 8.50. Compared with biochar or FeOx alone, a higher degradation efficiency (96.1%) and faster degradation rate (k = 0.100 min−1) of ACA were obtained by the B-FeOx composite at a catalyst dose of 2.0 g/L and PMS dose of 2.5 mM. The higher degradation efficiency of B-FeOx was attributed to the improved surface area and pore volume as well as the abundant reactive sites induced by the flower-like structure. Furthermore, the hydroxyl radical (•OH) generated in the B-FeOx/PMS system was the dominant radical for both ACA and 4-methylheptanoic acid degradation as demonstrated through radical quenching experiments. The presence of chloride ions in the B-FeOx/PMS system showed a suppression effect on the degradation of ACA and 4-methylheptanoic acid at Cl- concentrations between 5 and 20 mM. No significant difference in the degradation rates of ACA and 4-methylheptanoic acid was observed at different Cl- concentrations. Overall, the results of this study showed that the sludge (waste material)-based B-FeOx composite may have the potential to be utilized as PMS catalyst for the removal of NAs that are especially abundant in oil sands process water.

185. 题目: Soil microbial biomass carbon and freeze‐thaw cycles drive seasonal changes in soil microbial quotient along a steep altitudinal gradient
文章编号: N21090503
期刊: Journal of Geophysical Research: Biogeosciences
作者: Rui Cao, Wanqin Yang, Chenhui Chang, Zhuang Wang, Qin Wang, Yurui Jiang, Han Li, Bo Tan
更新时间: 2021-09-05
摘要: Understanding seasonal changes in soil microbial quotient (qMB, i.e., the MBC-to-SOC ratio) along altitudinal gradients and their dominant drivers is essential for determining the effects of environmental changes on the soil organic carbon pool. A 3-year in situ soil core incubation experiment was thus conducted in a dry valley shrub, a valley-mountain ecotone forest, a subalpine coniferous forest, an alpine coniferous forest, and an alpine meadow across a 2431-m altitudinal gradient on eastern the Qinghai-Tibetan Plateau. Soil qMB in the soil organic layer (OL) and mineral soil layer (ML) was measured at five critical periods. The average soil qMB was significantly higher in the alpine meadow than at other sites, with no significant difference among the other sites. The average soil qMB in this region was less than the global average value (1.2%), indicating that the soil organic carbon pool of the local ecosystem has higher stability and a lower mineralization potential than that of the other ecosystems globally. Seasonal variations in soil qMB differed along the altitudinal gradient. Significant increases in soil qMB during the 3-year incubation were mainly observed in the OL at higher altitudes, implying increased sensitivity of the soil organic carbon pool to environmental changes. MBC and soil freeze-thaw cycles were critical factors determining the altitudinal pattern and seasonal changes in soil qMB. Soil microbial biomass and freeze-thaw regime changes under global climate change scenarios will alter the balance between SOC microbial assimilation and maintenance respiration demands, affecting soil carbon biogeochemical cycling in mountainous ecosystems.

186. 题目: Experimental and Theoretical Studies into the Hydroxyl Radical Mediated Transformation of Propylparaben to Methylparaben in the Presence of Dissolved Organic Matter Surrogate
文章编号: N21090502
期刊: Water Research
作者: Yingyao He, Weiqi Su, Xue Zhai, Lijuan Luo, Tiangang Luan, Lihua Yang
更新时间: 2021-09-05
摘要: Dissolved humic and biogenic substances might be present in the aphotic zone and contribute to the fate of parabens in natural aquatic ecosystem under the fluctuation of water multi-parameters. Through the combination of batch tests with quantum chemical calculation, hydroxyl radical (•OH) mediated degradation of propylparaben (PP) to methylparaben (MP) has been confirmed in the present study. The interaction of dissolved oxygen with environmental relevant concentration of humic acid (HA), algal and bacterial cell lysis leads to a slow production of •OH. Aqueous PP undergoes a mild removal process with the pseudo-first order rate constant (10−7, s−1) higher at 7.43 in HA than at 3.30-4.89 in biogenic cell lysis. PP removal is correlated with the aromaticity of DOM surrogate and the produced •OH concentration, which could be enhanced by the increase of light intensity and DO other than HA. The •OH mediated process on PP removal has been confirmed by the linearly inhibited effect of tert-butanol while totally inhibited effects of higher concentration of sodium azide and co-existent chemical (17β-estradiol). Based on the detection of byproduct MP, two possible reaction pathways, •OH attacking at β-carbon (path-β) and terminal γ-carbon (path-γ) of the propyl side chain of PP, are proposed. Through the analysis of thermal and kinetics parameters, the •OH initiated H-abstraction and the resulting C-C bond cleavage leading to the formation of MP and acetaldehyde in path-β is confirmed to be the dominant reaction mechanism. Considering the universal occurrence of parabens and these DOM surrogates, this mild removal process has special implications for the self-purification of organic pollutants in natural aquatic ecosystems, especially in DOM-rich matrices in the aphotic zone.

187. 题目: A critical review of molybdenum sequestration mechanisms under euxinic conditions: Implications for the precision of molybdenum paleoredox proxies
文章编号: N21090501
期刊: Earth-Science Reviews
作者: Rachel Phillips, Jie Xu
更新时间: 2021-09-05
摘要: The observed difference in molybdenum (Mo) mobility and isotopic fractionation under oxic versus euxinic (i.e., anoxic and sulfidic) aqueous conditions provides a sound operational basis for the use of Mo geochemical signatures in ancient sedimentary records to infer palaeoceanographic redox conditions. While Mo is known to exist predominantly as molybdate (MoO42−) in oxic waters and convert into thiomolybdate species (MoOxS4-x2−) under euxinic conditions, the pathways that lead to Mo sequestration are highly debated. As mechanistic understanding of Mo sequestration is crucial for accurately reconstructing the chemistry of ancient oceans and constraining the timing and intensity of oxygenation events through Earth's history using Mo paleoproxies, we have closely examined the current proposed mechanisms for Mo sequestration across a wide range of euxinic conditions. Through compilation and comparison of such information, we aim to provide an integrated view of Mo sequestration processes, to identify the current controversies as well as the roots of such controversies, and importantly, to propose avenues for future research. Sequestration of Mo may occur through complexation with organic matter (OM), reactions with oxyhydroxide and sulfide mineral surfaces, incorporation into iron sulfide crystal structures, formation of Mo-sulfide, and cellular assimilation. However, several major questions remains unresolved, including whether OM complexation plays a significant role in overall sedimentary Mo accumulation, whether the reduction of Mo(VI) occurs during interaction with Fe-S clusters/precipitates and/or with OM, whether microbial enzymatic reduction of Mo(VI) is important in Mo sequestration, whether synergistic effects exist between the biological and abiotic processes in Mo sequestration, and whether differences in reactivity among the various thiomolybdate intermediate species and tetrathiomolybdate influence the Mo sequestration process. At the end of the review, the reliability of Mo paleoproxies is discussed and reevaluated.

188. 题目: Effects of FeSO4 dosage on nitrogen loss and humification during the composting of cow dung and corn straw
文章编号: N21090317
期刊: Bioresource Technology
作者: Juan Mei, Kai Ji, Lianghu Su, Mengting Wu, Xiaojie Zhou, Enshuai Duan
更新时间: 2021-09-03
摘要: The effects of FeSO4 on nitrogen loss and humification were investigated in the composting of cow dung and corn straw. The results showed that all groups met the ripening requirements after 50 days: the temperature was above 50°C for 12– 17 days; the products had pH values of 6.4–7.6, electrical conductivities of 1.06–1.33 ms·cm–1, NH4+-N contents of 37.2–61.8 mg kg–1, and the seed germination index of 95%–101%. FeSO4 reduced nitrogen losses by 9.21–15.65% compared to the control group. FeSO4 also improved the compost humification process: the humus substances (HS) contents in the compost product with FeSO4 were 109.82-129.86 g·kg–1, higher than 106.31 g·kg–1 in the control group. The compost product in 3.75% FeSO4 treatment had the highest maturity degree. This study showed that FeSO4 could inhibit the mineralization of organic matter during the composting and accelerate the formation of HS.

189. 题目: Effects of DOC addition from different sources on phytoplankton community in a temperate eutrophic lake: An experimental study exploring lake compartments
文章编号: N21090316
期刊: Science of The Total Environment
作者: Bárbara Medeiros Fonseca, Eti Ester Levi, Lea Westphalen Jensen, Daniel Graeber, Martin Søndergaard, Torben Linding Lauridsen, Erik Jeppesen, Thomas Alexander Davidson
更新时间: 2021-09-03
摘要: A mesocosm experiment was conducted in a temperate eutrophic lake with the hypotheses: 1) the addition of a labile form of DOC would trigger a more pronounced response in phytoplankton biomass and composition compared with a non-labile form; 2) DOC addition would increase phytoplankton biomass by co-inserting organic nutrients for phytoplankton growth; 3) DOC addition would change phytoplankton composition, in particular towards mixotrophic taxa due to higher DOC availability; and that 4) there would be differences in phytoplankton responses to DOC addition, depending on whether sediment was included or not. We used two types of mesocosms: pelagic mesocosms with closed bottom, and benthic mesocosms open to the sediment. The experiment ran for 29 days in total. The DOC addition occurred once, at Day 1. Besides the control, there were two treatments: HuminFeed® (non-labile DOC) at a concentration of 2 mg L−1, and a combination of 2 mg L−1 HuminFeed® and 2 mg L−1 DOC from alder leaf leachate (labile). Responses were detected only in the treatment with alder leaf extract. Ecosystem processes responded immediately to DOC addition, with the fall in dissolved oxygen and pH indicating an increase in respiration, relative to primary production (Day 2). In contrast, there was a delay of a few days in structural responses in the phytoplankton community (Day 6). Phytoplankton biomass increased after DOC addition, probably boosted by the phosphorus released from alder leaf extract. Changes in phytoplankton composition towards mixotrophic taxa were not as strong as changes in biomass, and happened only in the pelagic mesocosms. With the DOC addition, diatoms prevailed in benthic mesocosms, while the contribution of colonial buoyant cyanobacteria increased in the pelagic ones. This study points towards the necessity to look in greater detail at specific responses of phytoplankton to DOC concentration increases considering lake-habitat and sediment influence.

190. 题目: Effect of sewage sludge biochar on the soil nutrient, microbial abundance, and plant biomass: A sustainable approach towards mitigation of solid waste
文章编号: N21090315
期刊: Chemosphere
作者: Anees Ahmad, Pankaj Chowdhary, Nawaz Khan, Deepshi Chaurasia, Sunita Varjani, Ashok Pandey, Preeti Chaturvedi
更新时间: 2021-09-03
摘要: Soils functions, fertility, and microbial abundance may alter in various ways by the biochar amendments to the soil. This study revealed the way of pyrolysis temperature influences the biochar quality and its addition for improving soil properties. The SS biochar was synthesized via pyrolysis and characterized by SEM and FTIR for studying surface images and chemical functional groups. The biochar upon addition with soil was studied for physiological parameters of plants like seed germination index, root length, shoot length, biomass, metal (loid) analysis of soil, SS and SS biochar, total organic content, C: N ratio, NPK values, etc. Besides, combinations of biochar: soil {1:3 (25% + 75%), 1:1 (50% + 50%), and 3:1 (75% + 25%)} ratios were used for studying the effect of biochar on soil microbial community. The 16S rRNA metagenomic analysis revealed the dominance of phyla: Proteobacteria, Actinobacteria, and Acidobacteria that influence the soil nutrient cycle when applied at ratio 1:3. This study highlights the valorization of SS into biochar and studied the effect of biochar augmentation with soil; its impact on soil nutrients, microbial abundance, and plant biomass enhancement. The greener approach also mitigates and helps in the sustainable management of solid wastes, thus reducing GHGs emissions and improves nutrient cycling.

191. 题目: Adsorption of metolachlor by a novel magnetic illite–biochar and recovery from soil
文章编号: N21090314
期刊: Environmental Research
作者: Lu Liu, Xiaorou Wang, Wanyi Fang, Xiaohan Li, Dexin Shan, Yingjie Dai
更新时间: 2021-09-03
摘要: In this study, we investigated a highly efficient adsorbent that can be recycled from the soil. Walnut shells were used as raw materials to prepare original ecological biochar (OBC), illite modified biochar (IBC), FeCl3 modified biochar (magnetic biochar; MBC), and illite and FeCl3 modified biochar (IMBC), which were tested as low-cost adsorbents. The agents were used to remove metolachlor (MET) from soil. Scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, magnetic sensitivity curve analysis, and a series of adsorption experiments were conducted to study the interaction between illite and MBC, and the effect on MET adsorption. Compared with OBC, IMBC had more adsorption sites on the surface. IMBC improved the hole filling effect during the adsorption process. IMBC had more oxygen-containing functional groups and it performed better at removing organic matter through π-π interactions. According to the Langmuir model, the Q0 values for IBC, MBC, and IMBC were 91.74 mg g−1, 107.53 mg g−1, and 129.87 mg g−1, respectively, which were significantly higher than that for OBC (72.99 mg g−1). The response surface model was used to explore the optimal adsorption conditions for IMBC. After three regeneration cycles, the MET adsorption rate with IMBC was still 81.38% and the MET recovery rate was 98.12%. Therefore, IMBC was characterized as an adsorbent with high efficiency, low cost, and good recyclability. In addition, we propose a suitable agricultural system for recovering MBC on site in the field.

192. 题目: Biodegradation Kinetics of Ammonium Enriched Food Waste Digestate Compost with Biochar Amendment
文章编号: N21090313
期刊: Bioresource Technology
作者: M.K. Manu, Chen Wang, Dongyi Li, Sunita Varjani, Yunjie Xu, Narsi Ladumor, Lui Michael, Jun Zhou, Jonathan W.C. Wong
更新时间: 2021-09-03
摘要: High concentration of NH4+-N in food waste digestate (FWD) produced from biological treatment of food waste is considered as a major threat on the composting process resulting in production of immature compost. Hence, a laboratory batch composting study was conducted to examine the feasibility of using biochar as a physical additive to ameliorate the inhibitory effect of NH4+-N and to mitigate the nitrogen loss during FWD composting. FWD was co-composted with tobacco biochar at a dosage of 0%, 2.5%, 5% or 10% (dw) in bench-scale composters with a controlled aeration system. The addition of 10% biochar enhanced the degradation rate resulting in 44% higher carbon decomposition than the control. Besides, 10% biochar amendment reduced NH3 and N loss by 58% and 5%, respectively and significantly reduced NH4+-N content to HKORC limit of < 700 mg/kg dw within 5 days showing the beneficiary impact of biochar addition.

193. 题目: Response surface methodology to investigate the effects of operational parameters on membrane fouling and organic matter rejection in hard-shell encased hollow-fiber membrane
文章编号: N21090312
期刊: Chemosphere
作者: Hoseok Jang, Seong-Jik Park, Jeonghwan Kim
更新时间: 2021-09-03
摘要: The response surface methodology (RSM) was found useful statistical tool for understanding combined effect of filtration, backwashing time and dosage of sodium hypochlorite (NaOCl) added into backwash water as three operational parameters on transient behavior of transmembrane pressure (TMP) and organic rejection efficiency. Here, encased, hollow-fiber ultrafiltration (UF) system was developed for treating synthetic humic acid (HA) solution. To carry out RSM analysis, experimental matrix was designed by Box-Behnken model. Results showed that the NaOCl dosage for the chemical enhanced backwashing (CEB) as single parameter played most dominant role in fouling mitigation. Effect of hydraulic cleaning by applying the permeate backwashing only without performing the CEB was almost negligible to flush the fouling layer from membrane. Considering two correlated parameters, backwashing time combined with NaOCl dosage was found much more important than combination of other parameter such as filtration time to reduce fouling rate. Regardless of the operational parameters, the organic rejection efficiency was maintained 30% only. The RSM analysis also found that 40.1 min of filtration, 1.1 min of backwashing and 834 mg/L of NaOCl were optimum operating parameters to enhance both permeate recovery and fouling mitigation.

194. 题目: Rainfall stimulates large carbon dioxide emission during growing season in a forest wetland catchment
文章编号: N21090311
期刊: Journal of Hydrology
作者: Wei Ouyang, Pengtao Wang, Shaoqing Liu, Xin Hao, Zeshan Wu, Xintong Cui, Ri Jin, Weihong Zhu, Chunye Lin
更新时间: 2021-09-03
摘要: Forest wetland catchments are widely distributed in middle-high latitude and their hydrological and biogeochemical processes are sensitive to climate change. The net ecosystem exchange (NEE), meteorological forcing, and hydrological data in the Shuidong forest wetland catchment (SFWC) were continuously measured by eddy covariance (EC) tower and water monitoring instruments from 2019 to 2020. During rainy season, large carbon dioxide emission was detected with mean NEE value of 1.85 g C m-2 d-1 from local footprint area. Significant positive correlation was observed between daily NEE and air temperature (Tair), relative humidity (RH). We further found that the NEE was mainly controlled by ecosystem respiration (RE) instead of gross primary production (GPP), which might be caused by local high Q10 value. In addition, dissolved organic carbon (DOC) and dissolved organic (DON) concentrations near the stream outlet also had significant positive relationship with NEE, indicating the hydrological transport from upland forests may trigger the soil priming effect and result in higher CO2 emission within the local footprint area. Soil CO2 flux measurements from different land uses suggested that wetland may be the primary CO2 emission source during rainy season. Under the Representative Concentration Pathway (RCP) 8.5 scenario, the CO2 emission hotspot was expected to occur in this forest wetland catchment due to more frequent rainfall events predicted in this region.

195. 题目: Responses of steroid estrogen biodegradation to cyanobacterial organic matter biodegradability in the water column of a eutrophic lake
文章编号: N21090310
期刊: Science of The Total Environment
作者: Leilei Bai, Qi Ju, Chunliu Wang, Linqi Tian, Changhui Wang, Hui Zhang, Helong Jiang
更新时间: 2021-09-03
摘要: The co-occurrence of cyanobacterial harmful algal blooms and contaminants is an increasing environmental concern in freshwater worldwide. Our field investigations coupled with laboratory incubations demonstrated that the microbial degradation potential of 17β-estradiol (E2) with estrone as the intermediate was primarily driven by increased dissolved organic matter (DOM) in the water column of a cyanobacterial bloom. To explain the intrinsic contribution of cyanobacterial-derived DOM (C-DOM) to estrogen biodegradation, a combination of methods including bioassay, ultrahigh-resolution mass spectrometry, and microbial ecology were applied. The results showed that preferential assimilation of highly biodegradable structures, including protein-, carbohydrate-, and unsaturated hydrocarbon-like molecules sustained bacterial growth, selected for more diverse microbes, and resulted in greater estrogen biodegradation compared to less biodegradable molecules (lignin- and tannin-like molecules). The biodegradability of C-DOM decreased from 78% to 1%, whereas the E2 biodegradation rate decreased dramatically at first, then increased with the accumulation of recalcitrant, bio-produced lipid-like molecules in C-DOM. This change was linked to alternative substrate-induced selection of the bacterial community under highly refractory conditions, as suggested by the greater biomass-normalized E2 biodegradation rate after a 24-h lag phase. In addition to the increased frequency of potential degraders, such as Sphingobacterium, the network analysis revealed that C-DOM molecules distributed in high H/C (protein- and lipid-like molecules) were the main drivers structuring the bacterial community, inducing strong deterministic selection of the community assemblage and upregulating the metabolic capacity for contaminants. These findings provide strong evidence that estrogen biodegradation in eutrophic water may be facilitated by cyanobacterial blooms and provide a theoretical basis for ecological remediation of estrogen pollution.

196. 题目: Dissolved organic matter (DOM) removal from coking wastewater with efficient vanadium-titanium magnetite particle electrodes by 3D/EC/KPS system: Optimization, performance, and mechanism
文章编号: N21090309
期刊: Journal of Cleaner Production
作者: Weida Wang, Lili Wang, Ke Wang, Tingting Zhang, Yanbai Sun, Weiping Li
更新时间: 2021-09-03
摘要: In this study, vanadium titanomagnetite (VTM) was used as the dual action of three-dimensional particle electrode and activator, combined with electrochemical oxidation, to activate and degrade coking wastewater. First, the characteristics of VTM are analyzed by SEM-EDS, XRD, and XPS. Next, effects of VTM dosage, potassium persulfate (KPS) dosage, current density, and reaction time on COD, UV254, and DOC removal of coking wastewater were investigated, respectively. Regardless of the initial pH, the current density is 15 mA/cm2, COD, UV254 and DOC could be degraded effectively (94%, 86% and 58%, respectively) with the fixed VTM (4 g) and KPS (4 mmol/L) dosage after 30 min treatment due to the coupling effect in 3-dimensional/electrochemical/persulfate (3D/EC/KPS) system. In addition, the formation of free radicals was indirectly demonstrated by detecting the residual amount of S2O82−. On this basis, the degradation mechanism of coking wastewater by 3D/EC/KPS system was proposed comprehensively. In short, the electrochemical oxidation process coupled with VTM as particle electrode activating KPS technology shows a significant coupling effect in enhancing degradation of coking wastewater.

197. 题目: Novel insights into the adsorption of organic contaminants by biochar: A review
文章编号: N21090308
期刊: Chemosphere
作者: Zirui Luo, Bin Yao, Xiao Yang, Lingqing Wang, Zhangyi Xu, Xiulan Yan, Lin Tian, Hao Zhou, Yaoyu Zhou
更新时间: 2021-09-03
摘要: With rising concerns in the practical application of biochar for the remediation of environment influenced by various organic contaminants, a critical review to facilitate insights the crucial role that biochar has played in wastewater and polluted soil decontamination is urgently needed. This research therefore aimed to describe different intriguing dimensions of biochar interactions with organic contaminants, which including: (i) an introduction of biochar preparation and the related physicochemical properties, (ii) an overview of mechanisms and factors controlling the adsorption of organic contaminants onto biochar, and (iii) a summary of the challenges and an outlook of the further research needs in this issue. In the light of the survey consequences, the appearance of biochar indicates the potential in substituting the existing costly adsorbents, and it has been proved that biochar is one promising adsorbent for organic pollutants adsorption removal from water and soil. However, some research gaps, such as dynamic adsorption, potential environmental risks, interactions between biochar and soil microbes, novel modification techniques, need to be further investigated to facilitate its practical application. This research will be conductive to better understanding the adsorption removal of organic contaminants by biochar.

198. 题目: Soil Organic Carbon Enrichment Triggers In Situ Nitrogen Interception by Phototrophic Biofilms at the Soil–Water Interface: From Regional Scale to Microscale
文章编号: N21090307
期刊: Environmental Science & Technology
作者: Junzhuo Liu, Yanmin Zhou, Pengfei Sun, Yonghong Wu, Jan Dolfing
更新时间: 2021-09-03
摘要: Phototrophic biofilms are easy to grow at sediment/soil–water interfaces (SWIs) in shallow aquatic ecosystems and greatly impact nutrient biogeochemical cycles. However, the pathways by which they contribute to nitrogen interception and interact with sediment/soil remains largely unknown. Here, we conducted a field investigation in paddy fields in various regions of China and found that nitrogen immobilized in biofilm biomass significantly positively correlated with soil organic carbon (SOC) content. A microcosm experiment showed that this was due to increased bacterial and algal diversity, biomass accumulation, and inorganic nitrogen assimilation at high SOC, especially high dissolved organic carbon (DOC) levels. The metatranscriptomics results further verified that many KO groups of PSII, PSI, AP, and PC in antenna proteins and glutamate synthesis were distinctly expressed at elevated SOC and DOC levels. Our results elucidated the effects and possible pathways of how SOC enrichment triggers photosynthesis and nitrogen immobilization by phototrophic biofilms. The results will provide meaningful information for in situ nitrogen interception by using phototrophic biofilms at the SWI in human-made wetlands to change internal nitrogen cycling.

199. 题目: The impact of ammonium on the distillation of organic carbon in PM2.5
文章编号: N21090306
期刊: Science of The Total Environment
作者: Zemin Feng, Feixue Zheng, Chao Yan, Peng Fu, Yusheng Zhang, Zhuohui Lin, Jing Cai, Wei Du, Yonghong Wang, Juha Kangasluoma, Federico Bianchi, Tuukka Petäjä, Yuesi Wang, Markku Kulmala, Yongchun Liu
更新时间: 2021-09-03
摘要: Thermal desorption coupled with different detectors is an important analysis method for ambient carbonaceous aerosols. However, it is unclear how the compounds coexisting in both the gas and particle phases affect carbonaceous aerosol concentrations and measurements during thermal desorption. We observed matrix effects leading to a redistribution of different OC fractions (OC1 to OC4) during the thermal desorption process. These factors led to the formation of OC with low volatility (OC4), mainly from high-volatility OC (OC1 and OC2). Laboratory studies further indicated that ammonium promotes such matrix effects by transforming OC in the particle phase. Therefore, in addition to providing insights into the chemical evolution of OC during haze events, we argue that thermal-desorption-based OC measurements should be used with caution, which is an important step towards a more accurate measurement of OC in the ambient atmosphere.

200. 题目: Temporal changes in arsenic and lead pools in a contaminated sediment amended with biochar pyrolyzed at different temperatures
文章编号: N21090305
期刊: Chemosphere
作者: Matheus Bortolanza Soares, Felipe Hipólito dos Santos, Luís Reynaldo Ferracciú Alleoni
更新时间: 2021-09-03
摘要: Globally, tons of soils and sediments are experiencing degradation due to the presence of high concentrations of potentially toxic elements (PTEs), such as arsenic (As) and lead (Pb), in areas in the vicinity of metal mining activities. The addition of biochar to contaminated sediments is a promising in situ remediation approach, and the effects of pyrolysis temperature and biochar aging are important factors for the immobilization and fate of PTEs. In this study, we evaluated the temporal changes in pools of As and Pb in sediment amended with biochars produced from sugarcane (Saccharum officinarum) pyrolyzed at 350 (BC350), 550 (BC550), and 750 °C (BC750). Biochars were aged by natural process (without additional acid or heat), and changes in As and Pb pools were evaluated every 45 days until completing 180 days of incubation. Changes in the As and Pb pools were extracted with water (bioavailable), magnesium chloride (exchangeable), nitric acid (active geochemical fraction), and exchangeable Mehlich-3 (associated with organic matter). As and Pb available contents have increased over time. BC750 was more effective in reducing the bioavailable and exchangeable As contents, while BC550 and BC350 were more effective in reducing the contents of bioavailable and exchangeable Pb.