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61. 题目: Development of a VUV-UVC/peroxymonosulfate, continuous-flow Advanced Oxidation Process for surface water disinfection and Natural Organic Matter elimination: Application and mechanistic aspects
文章编号: N20112110
期刊: Journal of Hazardous Materials
作者: Zahra Amiri, Gholamreza Moussavi, Samira Mohammadi, Stefanos Giannakis
更新时间: 2020-11-21
摘要: Surface waters are often charged with high amounts of natural organic matter (NOM), organic contaminants and pathogens. In this work, a Vacuum UV/PMS process (VUV-UVC/PMS) was employed for treating river water, assessing the simultaneous NOM mineralization and bacterial disinfection. The VUV-UVC process (without PMS) decreased TOC concentration from 3.83 to 0.15 mg/L within 20 min, achieving complete disinfection. Adding 5 mg/L PMS increased the rate of TOC removal by 80%; complete removal of TOC was achieved in 15 min and disinfection was attained twice as fast. The mechanism of NOM mineralization was scrutinized; aeration played a considerable role due to oxygen supply, mixing, and inducing in-situ H2O2 production. HO• and SO4•− were the main radical species involved, alongside an important contribution of the matrix; sulfate enhanced TOC removal, due to the formation of additional radicals, underlining its importance. Furthermore, over 99% TOC reduction and complete disinfection was achieved in the VUV-UVC/PMS process operated under continuous-flow mode with a 2-min hydraulic retention time. Finally, the use of Atrazine (ATZ) as a probe compound and a series of scavenging tests led to an integrated proposal for the mineralization of NOM. Accordingly, the VUV-UVC/PMS process is evaluated as an efficient and promising technology for surface water treatment.

62. 题目: Effects of field scale in situ biochar incorporation on soil environment in a tropical highly weathered soil
文章编号: N20112109
期刊: Environmental Pollution
作者: Shih-Hao Jien, Yu-Lin Kuo, Chien-Sen Liao, Yu-Ting Wu, Avanthi Deshani Igalavithana, Daniel C.W. Tsang, Yong Sik Ok
更新时间: 2020-11-21
摘要: Biochar has been proven as a soil amendment to improve soil environment. However, mechanistic understanding of biochar on soil physical properties and microbial community remains unclear. In this study, a wood biochar (WB), was incorporated into a highly weathered tropical soil, and after 1 year the in situ changes in soil properties and microbial community were evaluated. A field trial was conducted for application of compost, wood biochar, and polyacrylamide. Microstructure and morphological features of the soils were characterized through 3D X-ray microscopy and polarized microscopy. Soil microbial communities were identified through next-generation sequencing (NGS). After incubation, the number of pores and connection throats between the pores of biochar treated soil increased by 3.8 and 7.2 times, respectively, compared to the control. According to NGS results, most sequences belonged to Anaerolinea thermolimosa, Caldithrix palaeochoryensis, Chthoniobacter flavus, and Cohnella soli. Canonical correlation analysis (CCA) further demonstrated that the microbial community structure was determined by inorganic N (IN), available P (AP), pH, soil organic C (SOC), porosity, bulk density (BD), and aggregate stability. The treatments with co-application of biochar and compost facilitated the dominance of Cal. palaeochoryensis, Cht. flavus, and Coh. soli, all of which promoted organic matter decomposition and ammonia oxidation in the soil. The apparent increases in IN, AP, porosity, and SOC caused by the addition of biochar and compost may be the proponents of changes in soil microbial communities. The co-application of compost and biochar may be a suitable strategy for real world biochar incorporation in highly weathered soil.

63. 题目: Physicochemical Properties of Aged Hydrochar in a Rice-Wheat Rotation System: A 16-Month Observation
文章编号: N20112108
期刊: Environmental Pollution
作者: Bingyu Wang, Haibin Fu, Lanfang Han, Huifang Xie, Lihong Xue, Yanfang Feng, Baoshan Xing
更新时间: 2020-11-21
摘要: The importance of hydrochar properties for soil application is well known, but the effects of natural aging on hydrochar properties remain ambiguous. The present study aimed to determine the shift patterns in the physicochemical properties of hydrochar through a 16-month soil column aging experiment conducted in a rice-wheat rotation system with hydrochars derived from a wheat straw at 220°C and 260°C. Obvious decreasing hydrophilic/polarity indices and increasing porosity, ash content, and stability occurred in aged hyrdrochar, which were due to the dissolved organic matter (DOM) leaching and the interaction with mineral content and fertilizer during the 16-month aging process. Besides, fewer C-OH, slightly more C=O, and higher aromaticity (C-C/C=C) in aged hydrochar were observed. Meanwhile, the relative abundance of the compounds containing only C, H, and O atoms in water extract of aged hydrochar decreased, while that of the compounds containing C, H, O, and N atoms increased during aging; these findings were attributed to the less labile DOM and microbial degradation and the retention of some plant-derived dissolved organic carbon, respectively. This study provided 16-month aging characterization data regarding alteration in hydrochar physicochemical properties, which was conducive to make a better understanding of the use of hydrochars as sustainable soil amendments from agroecosystems and environmental perspective.

64. 题目: Overlapping redox zones control arsenic pollution in Pleistocene multi-layer aquifers, the Po Plain (Italy)
文章编号: N20112107
期刊: Science of The Total Environment
作者: Marco Rotiroti, Tullia Bonomi, Elisa Sacchi, John M. McArthur, Rasmus Jakobsen, Alessandra Sciarra, Giuseppe Etiope, Chiara Zanotti, Veronica Nava, Letizia Fumagalli, Barbara Leoni
更新时间: 2020-11-21
摘要: Understanding the factors that control As concentrations in groundwater is vital for supplying safe groundwater in regions with As-polluted aquifers. Despite much research, mainly addressing Holocene aquifers hosting young (<100 yrs) groundwater, the source, transport, and fate of As in Pleistocene aquifers with fossil (>12,000 yrs) groundwaters are not yet fully understood and so are assessed here through an evaluation of the redox properties of the system in a type locality, the Po Plain (Italy). Analyses of redox-sensitive species and major ions on 22 groundwater samples from the Pleistocene arsenic-affected aquifer in the Po Plain shows that groundwater concentrations of As are controlled by the simultaneous operation of several terminal electron accepters. Organic matter, present as peat, is abundant in the aquifer, allowing groundwater to reach a quasi-steady-state of highly reducing conditions close to thermodynamic equilibrium. In this system, simultaneous reduction of Fe-oxide and sulfate results in low concentrations of As (median 7 μg/L) whereas As reaches higher concentrations (median of 82 μg/L) during simultaneous methanogenesis and Fe-reduction. The position of well-screens is an additional controlling factor on groundwater As: short screens that overlap confining aquitards generate higher As concentrations than long screens placed away from them. A conceptual model for groundwater As, applicable worldwide in other Pleistocene aquifers with reducible Fe-oxides and abundant organic matter is proposed: As may have two concentration peaks, the first after prolonged Fe-oxide reduction and until sulfate reduction takes place, the second during simultaneous Fe-reduction and methanogenesis.

65. 题目: Five-year soil warming changes soil C and N dynamics in a single rice paddy field in Japan
文章编号: N20112106
期刊: Science of The Total Environment
作者: Shuirong Tang, Weiguo Cheng, Rongui Hu, Julien Guigue, Satoshi Hattori, Keitaro Tawaraya, Takeshi Tokida, Minehiko Fukuoka, Mayumi Yoshimoto, Hidemitsu Sakai, Yasuhiro Usui, Xingkai Xu, Toshihiro Hasegawa
更新时间: 2020-11-21
摘要: Soil temperature is an important determinant of carbon (C) and nitrogen (N) cycling in terrestrial ecosystems, but its effects on soil organic carbon (SOC) and total nitrogen (TN) dynamics as well as rice biomass in rice paddy ecosystems are not fully understood. We conducted a five-year soil warming experiment in a single-cropping paddy field in Japan. Soil temperatures were elevated by approximate 2 °C with heating wires during the rice growing season and by approximate 1 °C with nighttime thermal blankets during the fallow season. Soil samples were collected in autumn after rice harvest and in spring after fallow each year, and anaerobically incubated at 30 °C for four weeks to determine soil C decomposition and N mineralization potentials. The SOC and TN contents, rice biomass, dissolved organic carbon (DOC) and microbial biomass carbon (MBC) concentrations were measured in the study. Soil warming did not significantly enhance rice aboveground and root biomasses, but it significantly decreased SOC and TN contents and thus decreased soil C decomposition and N mineralization potentials due to depletion of available C and N. Moreover, soil warming significantly decreased DOC concentration but significantly increased MBC concentration. The ratios of C decomposition potential to N mineralization potential, decomposition potential to SOC, and N mineralization to TN were not affected by soil warming. There were significant seasonal and annual variations in SOC, C decomposition and N mineralization potentials, soil DOC and MBC under each temperature treatments. Our study implied that soil warming can decrease soil C and N stocks in paddy ecosystem probably via stimulating microbial activities and accelerating the depletion of DOC. This study further highlights the importance of long-term in situ observation of C and N dynamics and their availabilities in rice paddy ecosystems under increasing global warming scenarios.

66. 题目: Rhizosphere bacterial and fungal community succession patterns related to root growth of poplar fine roots
文章编号: N20112105
期刊: Science of The Total Environment
作者: Qiliang Zhu, Nian Wang, Baoli Duan, Qingkui Wang, Yanping Wang
更新时间: 2020-11-21
摘要: Understanding the succession patterns of microbial community along root growth provides deep insights into interaction between fine roots and microbes. In the study, we investigated this issue using fine roots from poplar trees and grouped these fine roots into three growth stages: newborn white roots (WR), mature yellow roots (YR) and aging brown roots (BR). Root surface traits were observed under a scanning electron microscopy (SEM). Adhered soils on roots of the three growth stages were grouped into the three soil compartments, correspondingly. The 16S rRNA and ITS1 region were sequenced for bacteria and fungi inhabiting rhizosphere soils, respectively. Phospholipid fatty acid (PLFA) technology was employed to examine the biomass of bacterial and fungal communities. The anatomical traits of fine roots show apparent differences among the WR, YR and BR. Both bacteria and fungi have 25 dominant genera with a relative abundance over 1%, of which, both four genera of the bacteria (Bacillus, Burkholderia, Ralstonia and Dyella) differ in abundance among the WR, YR and BR soil compartments and four genera of the fungi (Fusarium, Chaetomium, Penicillium and Scleroderma) also differ in abundance among these soil compartments. The operational taxonomic units (OTUs) showed the highest richness in the WR soil compartment for bacteria and in the YR soil compartment for fungi, indicating a different succession pattern between the bacterial and fungal communities. Furthermore, the biomass of bacterial community is larger than the fungal community according to PLFAs, and both decreased along fine root growth. The total carbon (TC) in the soil increases along root growth while the dissolved organic carbon (DOC) decreases. Redundancy analysis (RDA) shows a close correlation between twelve dominant bacteria genera and the total organic carbon (TOC), the readily oxidizable organic carbon (ROC) and DOC and ten dominant fungi genera with the TOC and ROC. In conclusion, our results indicate that fine roots growth has shaped the composition and structure of root associated bacteria and fungi community.

67. 题目: Investigating the spatio-temporal variability of soil organic carbon stocks in different ecosystems of China
文章编号: N20112104
期刊: Science of The Total Environment
作者: Shuai Wang, Li Xu, Qianlai Zhuang, Nianpeng He
更新时间: 2020-11-21
摘要: Soil organic carbon (SOC) significantly influences soil fertility, soil water holding capacity, and plant productivity. In this study, we applied two boosted regression tree (BRT) models to map SOC stocks across China in the 1980s and the 2010s. The models incorporated nine environmental variables (climate, topography, and biology) and 8897 (in the 1980s) and 4534 (in the 2010s) topsoil (0–20 cm) samples. During the two study periods, 20% of the soil samples were randomly selected for model testing, and the remaining samples were used as a training set to construct the models. The verification results showed that incorporating climate environment variables significantly improved the model prediction in both study periods. Mean annual temperature, mean annual precipitation, elevation, and the normalized difference vegetation index were the dominant environmental factors affecting the spatial distribution of SOC stocks. The full-variable model predicted similar spatial distributions of SOC stocks for the 1980s and the 2010s. SOC stocks in China showed an increasing trend over the past 30 years, from 3.9 kg m–2 in the 1980s to 4.6 kg m–2 in the 2010s. In both periods, topsoil SOC stocks were mainly stored in agroecosystems, forests, and grasslands in the 1980s, with values of 9.5, 12.0, and 11.4 Pg C, respectively. Our study provides reliable information on Chain’s carbon distribution, which can be used by land managers and the national government to formulate relevant land use and carbon sequestration policies.

68. 题目: Effects of biochar addition on the abundance, speciation, availability, and leaching loss of soil phosphorus
文章编号: N20112103
期刊: Science of The Total Environment
作者: Lu Yang, Yunchao Wu, Yichu Wang, Weiqi An, Jie Jin, Ke Sun, Xiangke Wang
更新时间: 2020-11-21
摘要: As a promising soil amendment, biochar has demonstrated its potential for influencing soil nutrient transformations. The effects of biochar on soil phosphorus (P) transformations have received much less attention than its effects on carbon cycling. A review of the literature reveals that biochar applications to soils may have notable effects on the abundance, speciation, availability, and leaching loss of soil P. However, a comprehensive and systematic understanding of the biochar-induced environmental behavior of soil P has not been obtained so far. Therefore, in this review, we analyzed and identified the known and potential mechanisms through which biochar affects P behavior in soils: (1) biochar as a source of P provides soluble and exchangeable P to soil; (2) biochar enhances the availability of endogenic soil P by influencing P-related complexation and metabolism effects; and (3) biochar affects P leaching losses directly or indirectly by adsorbing P, improving P retention by soil, and facilitating P assimilation by plants. By presenting a broad and detailed illustration of P behaviors in biochar-amended soils, this paper suggests that the application of biochar to soils will help enlarge soil P pools, increase soil P availability, and decrease P leaching losses from soil. Additional studies are needed to further elucidate the long-term effects of biochar addition on soil P transformations, explore how biochar-derived dissolved organic matter (BDOM) affects the mobility and availability of soil mineral-associated P, and examine the transport of particulate P in biochar-amended soils.

69. 题目: Hydrochar and pyrochar for sorption of pollutants in wastewater and exhaust gas: A critical review
文章编号: N20112102
期刊: Environmental Pollution
作者: Ziyun Liu, Zihan Wang, Hongxu Chen, Tong Cai, Zhidan Liu
更新时间: 2020-11-21
摘要: Pollutants in wastewater and exhaust gas bring out serious concerns to public health and the environment. Biochar can be developed as a sustainable adsorbent originating from abundant bio-wastes, such as agricultural waste, forestry residue, food waste and human waste. Here we highlight the state-of-the-art research progress on pyrochar and hydrochar for the sorption of pollutants (heavy metal, organics, gas, etc) in wastewater and exhaust gases. The adsorption performance of pyrochar and hydrochar are compared and discussed in-depth, including preparation procedures (carbonization and activation), sorption possible mechanisms, and physiochemical properties. Challenges and perspective for designing efficient and environmental benign biochar-based adsorbents are finally addressed.

70. 题目: Spontaneous assembly of microbial extracellular polymeric substances into microcapsules involved in trapping and immobilizing degradation-resistant oxoanions
文章编号: N20112101
期刊: Science of The Total Environment
作者: Qian Wang, Kai Chen, Shuhan Huang, Xuezhu Zhu, Fuxing Kang
更新时间: 2020-11-21
摘要: Despite the ubiquity of microbial extracellular polymeric substances (EPS) in soils and aquatic environments, the roles played by EPS in the nonreductive transformation of toxic and degradation-resistant oxoanions are poorly understood. Here, we used perchlorate, which is ubiquitous in surface environments, as an initiator to study the spontaneous assembly of EPS into microcapsules involved in trapping and immobilizing oxoanions. The results confirmed that ClO4- oxoanions could be rapidly trapped in 20 minutes by EPS extracted from a common Bacillus subtilis, whereas no chemical reduction of ClO4- occurred in 48 h. Integrated spectroscopic analyses with florescence quenching microtitration and theoretical models showed that amino functionalities of EPS are responsible for sequestering ClO4-, with lower pH values being more favorable to formation of EPS-ClO4- micelles. Combined molecular dynamics scheme with wave function analyses showed that besides amino residues, the protonated side-chain amino groups in the basic proteins have a greater capacity for sequestering ClO4- through a noncovalent H-bonding mechanism in which dissociable protons serve as the nodes to bridge ClO4-. A quantitative association between the number of hydrogen bonds and bioavailability revealed that immobilization by EPS mitigates the uptake of toxic oxoanions by forage ryegrass, reducing their risk exposure to edible produce.

71. 题目: Microbial mechanism of biochar addition on nitrogen leaching and retention in tea soils from different plantation ages
文章编号: N20112016
期刊: Science of The Total Environment
作者: Pengfei Chen, Yizhen Liu, Chaoyang Mo, Zhenhui Jiang, Jingping Yang, Jingdong Lin
更新时间: 2020-11-20
摘要: The effect of biochar additions on N leaching and retention in tea soils and its microbial mechanism are still unclear. In this study, effects of biochar additions at rates of 0, 3% and 6% on N leaching, N retention and microbial responses in two tea soils with 20- and 60-year plantation ages were investigated under application with 15N-labeled urea. The results showed that cumulative mass of leached NH4+-N, NO3−-N and TN was reduced by 20.9%–91.9%, 35.1%–66.9% and 40.0%–72.8% under biochar additions, respectively. The retention of TN in soil was increased by 1.2%–5.8% under biochar amendment. Fertilizer-N in the leachate was reduced by 28.8%–62.1%, while fertilizer-N retention in the soils was enhanced by 3.2%–23.9% with biochar application. Biochar addition of 6% showed the highest mitigation of N leaching and enhancement of TN retention across the two soils. Biochar additions increased soil microbial biomass and enzyme activities and changed the bacterial community composition, indicating that biochar addition increased the microbial N requirement, stimulated soil N cycling, including nitrification and denitrification processes, and enhanced microbial N immobilization in the tea soils. Those microbial responses to biochar addition were higher in 60-year-old soil relative to 20-year-old soil, leading to a higher enhancement of N retention and mitigation of N leaching. Soil pH was the prime factor that influenced soil microbes, and it strongly correlated with microbial biomass, enzyme activity, the relative abundance of dominant phyla and α-diversity indices. Therefore, the enhancement of microbial biomass, activity and shifts of bacterial community composition related to N cycling in response to biochar additions that increased the soil pH could be an important mechanism to better understand the biochar-induced N leaching mitigation and N retention enhancement in tea soils under different plantation ages.

72. 题目: Biochar industry to circular economy
文章编号: N20112015
期刊: Science of The Total Environment
作者: Qiang Hu, Janelle Jung, Dexiang Chen, Ken Leong, Shuang Song, Fanghua Li, Babu Mohan, Zhiyi Yao, Arun Kumar Prabhakar, Xuan Hao Lin, Ee Yang Lim, Le Zhang, Gupta Souradeep, Yong Sik Ok, Harn Wei Kua, Sam F.Y. Li, Hugh T.W. Tan, Yanjun Dai, Yen Wah Tong, Yinghong Peng, Stephen Joseph, Chi-Hwa Wang
更新时间: 2020-11-20
摘要: Biochar, produced as a by-product of pyrolysis/gasification of waste biomass, shows great potential to reduce the environment impact, address the climate change issue, and establish a circular economy model. Despite the promising outlook, the research on the benefits of biochar remains highly debated. This has been attributed to the heterogeneity of biochar itself, with its inherent physical, chemical and biological properties highly influenced by production variables such as feedstock types and treating conditions. Hence, to enable meaningful comparison of results, establishment of an agreed international standard to govern the production of biochar for specific uses is necessary. In this study, we analyzed four key uses of biochar: 1) in agriculture and horticulture, 2) as construction material, 3) as activated carbon, and 4) in anaerobic digestion. Then the guidelines for the properties of biochar, especially for the concentrations of toxic heavy metals, for its environmental friendly application were proposed in the context of Singapore. The international status of the biochar industry code of practice, feedback from Singapore local industry and government agencies, as well as future perspectives for the biochar industry were explained.

73. 题目: Magnetic biochar reduces phosphorus uptake by Phragmites australis during heavy metal remediation
文章编号: N20112014
期刊: Science of The Total Environment
作者: Jingtao Wu, Rong Huang, Qingqiu Zhou, Huanping Lu, Feng Li, Kejun Wu, Zhian Li
更新时间: 2020-11-20
摘要: Magnetic biochar has been widely used in the removal of aquatic pollutants due to its strong adsorption capacity and recyclability. However, the nutrient deficiency caused by magnetic biochar reduces plant performance and limits its use. The effects of magnetic biochar (derived from either eucalyptus wood or pig manure compost) on soil Cd, Zn, and Pb bioavailability to Phragmites australis L. (reed) and soil microbial community were investigated in a pot experiment. We also examined treatments of magnetic biochar with P supplementation and unmodified biochar with Fe addition to elucidate the mechanism by which magnetic biochar affects plant growth. We found that the addition of magnetic biochar significantly reduced the concentrations of available heavy metals in soil and inhibited heavy metal uptake by reeds. It also promoted the formation of iron plaque on reed roots to inhibit metal translocation. However, compared to unmodified biochar, magnetic biochar reduced reed performance, as indicated by the reduced plant biomass and photosynthetic ability, and it also reduced the biomass of soil bacteria and fungi. This was due to the interception of P by the iron plaque and the reduced concentration of soil available P. Collectively, although magnetic biochar exhibited a strong potential for heavy metal remediation, P supplementation is recommended to maintain plant performance and soil health when applying magnetic biochar.

74. 题目: Waste valorization: Transforming the fishbone biowaste into biochar as an efficient persulfate catalyst for degradation of organic pollutant
文章编号: N20112013
期刊: Journal of Cleaner Production
作者: Xiaoya Ren, Jingjing Wang, Jiangfang Yu, Biao Song, Haopeng Feng, Maocai Shen, Hao Zhang, Jiajing Zou, Guangming Zeng, Lin Tang, Jiajia Wang
更新时间: 2020-11-20
摘要: Fishbone is a major by-product of fishing processing and how to deal with the increasingly generated fishbone has been a big challenge. In an effort to convert the low-value waste into valuable material, this research explores the valorization of fishbone biowaste, which can be transformed into biochar as a persulfate activator for phenol removal. The fishbone derived biochar (FBBC) was prepared by one-step pyrolysis without additional template. The catalytic efficiency of FBBC increases with pyrolysis temperature, with FBBC-800 (pyrolyzed at 800 °C) exhibiting the best performance of 100% phenol (20 mg/L) removal within 60 min at the catalyst dosage of 0.1 g/L, which is comparable to other recently reported carbon-based catalysts but with the advantage of easy preparation, low cost and wastes valorization. The high efficacy of FBBC-800 is related to its large surface area (758.44 m2/g), carbonyl group and defective structure. In the FBBC-800/peroxydisulfate/phenol system, both radical and non-radical pathways are involved, among which hydroxyl radical is more important in radical pathway while singlet oxygen dominates in non-radical pathway. Electron transfer plays a key role in this process through electron capture experiment and electrochemical characterization. This study proposes a new strategy for the valorization of fishbone, and provides the guidance for the structure design of carbon-based catalyst for persulfate activation.

75. 题目: Enhanced nitrogen and phosphorus adsorption performance and stabilization by novel panda manure biochar modified by CMC stabilized nZVZ composite in aqueous solution: Mechanisms and application potential
文章编号: N20112012
期刊: Journal of Cleaner Production
作者: Meijing Wang, Sikui Hu, Qingguo Wang, Ying Liang, Chaorong Liu, Hao Xu, Qian Ye
更新时间: 2020-11-20
摘要: Direct discharge of water containing excessive nitrogen and phosphorus concentrations into the aquatic environment can lead to loss of resources and eutrophication. Biochar prepared by thermochemical treatment of feedstocks, particularly the metal modified biochar, which can be used as a new adsorbent for aquatic environmental treatment. Herein, a novel panda manure biochar (PMBC) modified by carboxymethyl cellulose (CMC) stabilized nano zero-valent zinc (nZVZ-CMC-PMBC) was developed and applied for efficiently removal of NH4+and PO43-. Batch sorption experiments verified the kinetics and equilibrium isotherms of NH4+ and PO43- adsorption, the results showed that PMBC had significantly better adsorption performance on nitrogen and phosphorus compared to bamboo biochar. Moreover nZVZ-CMC-PMBC demonstrated maximum theoretical adsorption capacities of 40.31 mg•g-1 NH4+-N and 154.30 mg•g-1 total phosphorus (TP). Characterization result of SEM-EDS, BET, FTIR, XRD and XPS reveal that PMBC had larger specific surface area and pore diameter than bamboo biochar which confirmed that PMBC contained more adsorption sites. As for nZVZ-CMC-PMBC, crystalline nZVZ flakes are dispersed and impregnated into the frame of CMC-nZVZ- PMBC composite, characterization analysis unveiled the formed complexes on its surface. Therefore, the adsorption mechanism of nZVZ-CMC-PMBC for NH4+-N and TP mainly involved Zn2+ precipitates, surface electrostatic attraction and surface complexation.

76. 题目: Responses of phenanthrene degradation to the changes in bioavailability and microbial community structure in soils amended with biochars pyrolyzed at low and high temperatures
文章编号: N20112011
期刊: Journal of Hazardous Materials
作者: Zheng Ding, Fan Zhang, Haofei Gong, Ning Sun, Jianjun Huang, Jie Chi
更新时间: 2020-11-20
摘要: This study investigated the impact of wheat straw biochars pyrolyzed at temperatures of 100-700 ℃ (BC100-BC700) on biodegradation of phenanthrene in soils. During a 42-day experiment, biochar amendment reduced the biodegradation ratio of phenanthrene in soils by no change-77.0%. The biodegradation ratio decreased with the increase of pyrolysis temperature from 100 to 400 ℃ and then increased with the increase of pyrolysis temperature from 400 to 700 ℃, exhibiting a U-shape. Meanwhile, desorbing fraction of phenanthrene extracted by n-butanol declined with increasing pyrolysis temperature. Biochar-derived dissolved organic carbon (DOC) obviously influenced the soil DOC contents which were negatively correlated with the total relative abundances of dominant polycyclic aromatic hydrocarbon (PAH)-degraders. These results indicated that in soils amended with biochars pyrolyzed at low temperatures (i.e. 100-400 ℃), both the reduced bioavailability of phenanthrene and the reduced PAH-degrader abundance resulted in decreasing phenanthrene degradation with pyrolysis temperature. In soils amended with biochars pyrolyzed at high temperatures (i.e. 500-700 ℃; HT-biochars), two possible reasons contribute to increasing phenanthrene degradation with pyrolysis temperature: (1) high sorbed-phenanthrene concentration due to large specific surface area and high aromaticity of the biochars, and (2) the increased dominant PAH-degrader abundance for the removal of sorbed-phenanthrene due to the impact of HT-biochars on soil properties (mainly on DOC content).

77. 题目: Characterization and mechanism of Mn(II)-based mixotrophic denitrifying bacterium (Cupriavidus sp. HY129) in remediation of nitrate (NO3--N) and manganese (Mn(II)) contaminated groundwater
文章编号: N20112010
期刊: Journal of Hazardous Materials
作者: Yihan Bai, Junfeng Su, Qiong Wen, Tinglin Huang, Qiao Chang, Amjad Ali
更新时间: 2020-11-20
摘要: The co-contamination of groundwater with nitrate (NO3--N) and manganese (Mn(II)) is a global issue that needs to be efficiently remediated. In this research, a novel denitrifying and manganese-oxidizing strain HY129 was isolated from the sediments sample of a drinking water and identified as Cupriavidus sp. HY129. The remediation ability of strain HY129 regarding the nitrate and Mn(II) pollution were investigated. The removal efficiency of nitrate and Mn(II) were 99.81% (0.229 mgL-1h-1) and 87.24% (0.233 mgL-1h-1) in bacterial culture after 72 h, respectively. Moreover, the addition of Mn(II) significantly enhanced the denitrification process, while excessive concentration of Mn(II) caused more NO2--N accumulation. The impacts of adsorption and oxidation activity on Mn(II) removal were investigated. Protein in extracellular polymeric substance (EPS) which produced in the Mn-oxidizing process was speculated to be the main cause of extracellular adsorption of Mn(II). Characterization of biogenic manganese oxides (BMO) confirmed the formation of high-valent manganese and the trapping experiment with sodium pyrophosphate (NaPP) demonstrated the existence of Mn(III)-intermediates. Furthermore, multicopper oxidase gene amplification provided evidence for the molecular biology of Mn(II) oxidation by strain HY129.

78. 题目: Effect of alkaline and chemically engineered biochar on soil properties and phosphorus bioavailability in maize
文章编号: N20112009
期刊: Chemosphere
作者: Muhammad Farooq Qayyum, Ghulam Haider, Maria Iqbal, Sajida Hameed, Niaz Ahmad, Muhammad Zia ur Rehman, Abdul Majeed, Muhammad Rizwan, Shafaqat Ali
更新时间: 2020-11-20
摘要: Phosphorous (P) fixation in alkaline calcareous soils is a serious concern worldwide and acidified-biochar application has been proposed to improve the agronomic benefits of applied P. The present study aims to improve understanding of P transformation process in an alkaline soil following different biochar amendments (rice-husk biochar (RHB), sugarcane-bagasse biochar (SWB) and wheat-straw biochar (WSB)), chemically engineered (acidification with 1N HCl or washing with distilled water (pristine biochar)) along with or without P at 60 mg/kg. A pot experiment was conducted with three biochars (RHB, SWB, WSB) and control, two chemical modifications (acidic and pristine), and two P-levels (without or with P). A pot study by growing spring maize and a parallel incubation study were done to test the treatment effects on P transformation. Results demonstrated that acidified SBC and WSB increased the plant P uptake and dry-matter yield by 40% and 29.7%, respectively, with P-supply. Both pristine or acidified RHB produced 80.5% and 110.7%, more root dry-matter, respectively, compared to respective controls without P. Non-acidified WSB along with P showed significantly higher Olson’s P in incubation study. While in case of acidification along with P addition, RHB exhibited greater P availability, but it was inconsistent at different times during incubation. It can be concluded that acidified biochar amendments have potential to improve P management with inconsistent results. It is difficult to rule out that acidification of biochars is a pre-requisite for alkaline soils for P improvement. Further research is needed to explore site-specific P management for sustainable crop production.

79. 题目: Review of Aquatic Toxicity of Pharmaceuticals and Personal Care Products to Algae
文章编号: N20112008
期刊: Journal of Hazardous Materials
作者: Xiaying Xin, Gordon Huang, Baiyu Zhang
更新时间: 2020-11-20
摘要: Pharmaceuticals and Personal Care Products (PPCPs) have been frequently detected in the environment around the world. Algae play a significant role in aquatic ecosystem, thus the influence on algae may affect the life of higher trophic organisms. This review provides a state-of-the art overview of current research on the toxicity of PPCPs to algae. Nanoparticles, contained in personal care products, also have been considered as the ingredients of PPCPs. PPCPs could cause unexpected effects on algae and their communities. Chlorophyta and diatoms are more accessible and sensitive to PPCPs. Multiple algal endpoints should be considered to provide a complete evaluation on PPCPs toxicity. The toxicity of organic ingredients in PPCPs could be predicted through quantitative structure-activity relationship model, whereas the toxicity of nanoparticles could be predicted with limitations. Light irradiation can change the toxicity through affecting algae and PPCPs. pH and natural organic matter can affect the toxicity through changing the existence of PPCPs. For joint and tertiary toxicity, experiments could be conducted to reveal the toxic mechanism. For multiple compound mixture toxicity, concentration addition and independent addition models are preferred. However, there has no empirical models to study nanoparticle-contained mixture toxicity. Algae-based remediation is an emerging technology to prevent the release of PPCPs from water treatment plants. Although many individual algal species are identified for removing a few compounds from PPCPs, algal-bacterial photobioreactor is a preferable alternative, with higher chances for industrial applications.

80. 题目: Complexing characteristics between Cu(Ⅱ) ions and dissolved organic matter in combined sewer overflows: Implications for the removal of heavy metals by enhanced coagulation
文章编号: N20112007
期刊: Chemosphere
作者: Zhen-liang Liao, Zhi-chao Zhao, Jing-cheng Zhu, Hao Chen, Dai-zong Meng
更新时间: 2020-11-20
摘要: Enhanced coagulation has been widely used in storm tanks to remove heavy metal ions (HMs) from combined sewer overflows (CSOs), but faces challenges on removing the HMs bound to dissolved organic matter (DOM) with small molecular weight (MW). DOM ubiquitously existing in CSOs generally contains a large distribution range of MW, which can significantly impact the MW distribution of HMs by complexing reaction, thereby adding uncertainties for the removal efficiency of coagulation. Therefore, realizing the potential MW distribution of the HMs bound to CSO-DOM is greatly important for cost-effectively removing HMs from CSOs in the coagulation process. This paper presents a comprehensive approach of ultrafiltration, fluorescence quenching titration, excitation−emission matrix parallel factor analysis, complexation model, and two-dimensional correlation fluorescence spectroscopy for exploring the MW-based complexing characteristics between Cu(II) ions and CSO-DOM components. Results show that: (1) Cu(II) ions that bound to the CSO-DOM were mainly distributed in the MW range of < 5 kDa, which makes them very difficult to be removed from CSOs by coagulation technique. (2) Concentration effect and molecular composition exerted great impacts on the MW distribution of the Cu(II) ions bound to CSO-DOM. (3) The humic-like component of terrestrial origin with the MW range of 100 kDa∼0.45 μm possessed high binding stability, capacity, and priority with Cu(II) ions, and they could be used at a high concentration to promote the removal efficiency of coagulation for Cu(Ⅱ) ions of CSOs by competitive complexation and inter-molecular bridging.