论文检索

主页 | 软件工具 | 课题库 | 公众号
:



总访问量:869243

总访客量:31525

关键词:
Organic Matter |
DOM |
POM |
Soil OM |
Sediment OM |
Organic Carbon |
Organic Nitrogen |
Biomarker |
Humic Substances |
Fulvic Substances |
Humins |
Biochar |
Black Carbon |
GDGT |
Lignin |
Free Radical |
...
最新文章  | 
昨日文章 | 
前日文章
期刊:
Agriculture, Ecosystems & Environment |
Agricultural Water Management |
Applied Geochemistry |
Applied Soil Ecology |
Aquatic Geochemistry |
Atmospheric Research |
Biogeochemistry |
Biogeosciences |
Biology and Fertility of Soils |
Bioresource Technology |
CATENA |
Chemical Engineering Journal |
Chemical Geology |
Chemosphere |
CLEAN - Soil, Air, Water |
Colloids and Surfaces A: Physicochemical and Engineering Aspects |
Deep Sea Research Part II: Topical Studies in Oceanography |
Earth-Science Reviews |
Ecological Engineering |
Ecology Letters |
Ecology |
Ecotoxicology and Environmental Safety |
Environment International |
Environmental Earth Sciences |
Environmental Geochemistry and Health |
Environmental Monitoring and Assessment |
Environmental Pollution |
Environmental Research |
Environmental Science & Technology |
Environmental Science and Pollution Research |
Environmental Science: Processes Impacts |
Environmental Science: Water Research & Technology |
Environmental Toxicology and Chemistry |
Estuarine, Coastal and Shelf Science |
European Journal of Soil Science |
Forest Ecology and Management |
Geochimica et Cosmochimica Acta |
Geoderma |
Geophysical Research Letters |
Global Change Biology |
Global Biogeochemical Cycles |
Groundwater |
Harmful Algae |
International Journal of Coal Geology |
Journal of Environmental Chemical Engineering |
Journal of Environmental Management |
Journal of Environmental Sciences |
Journal of Geophysical Research: Biogeosciences |
Journal of Geophysical Research: Oceans |
Journal of Hazardous Materials |
Journal of Membrane Science |
Journal of Soils and Sediments |
Land Degradation & Development |
Limnology and Oceanography |
Marine Chemistry |
Marine Pollution Bulletin |
Nature Communications |
Nature Geoscience |
Ocean Science Journal |
Oikos |
Organic Geochemistry |
Palaeogeography, Palaeoclimatology, Palaeoecology |
Plant and Soil |
Progress in Oceanography |
Quaternary International |
Science of The Total Environment |
Sedimentary Geology |
Separation and Purification Technology |
Soil and Tillage Research |
Soil Biology and Biochemistry |
Waste Management |
Water Research |
Water, Air, & Soil Pollution |
Wetlands |
...

所有论文

81. 题目: Sedimentary pyrites and C/S ratios of mud sediments on the East China Sea inner shelf indicate late Pleistocene-Holocene environmental evolution
文章编号: N22061805
期刊: Marine Geology
作者: Xiting Liu, Mingyu Zhang, Anchun Li, Jiang Dong, Kaidi Zhang, Yu Gu, Xin Chang, Guangchao Zhuang, Qing Li, Houjie Wang
更新时间: 2022-06-18
摘要: Sedimentary pyrite and the ratio between organic carbon and pyrite sulfur (C/S ratio) have been widely used as paleosalinity indicators to distinguish between marine and freshwater environments. However, in unsteady marine environments with strong physical reworking, the formation of pyrite is limited, leading to a high C/S ratio, as is the case in freshwater environments; thus, whether C/S ratios can identify unsteady marine environments in sedimentary strata is still a controversial topic. To calculate the availability of these classic indicators in unsteady environments, we analysed multiple indicators of core sediments obtained from the inner shelf of the East China Sea. Our results show that there are no pyrite aggregates in the sediments deposited under terrestrial conditions before 13.1 ka. During this period, the C/S ratios are higher than 2.8, representing the characteristics of sediment deposited in freshwater environments, which is also supported by low Sr/Ba ratios. When the core site was initially affected by seawater intrusion at approximately 13.1 ka, pyrite aggregates appeared for the first time, accompanied by a rapid decrease in C/S ratios, indicating a brackish tidal flat environment. We find that the C/S ratio overlaps between tidal flat and inner shelf environments, but the relatively high content of pyrite aggregates and fine-grained sediments in the shelf sediments can effectively separate these two environments. Our results further reveal that the mud depocentre initially developed at approximately 7.5 ka when the sea level reached its highstand. These new findings suggest that geochemical indicators should always be used in conjunction with sedimentary and paleoecological evidence to prevent biased conclusions.

82. 题目: Essential role of sunlight irradiation in aqueous micropollutant transformations: Influence of the water matrix and changes in toxicities
文章编号: N22061804
期刊: Environmental Science: Water Research & Technology
作者: De-Xiu Wu, Wen-Cheng Huang, Zi-Fan Liang, Wen-Long Wang, Tao Xiang, Gang Wang, Ye Du, Qianyuan Wu
更新时间: 2022-06-18
摘要: Various micropollutants (MPs) that exist in surface water and treated wastewater have been continuously arousing concerns because of their harmful ecological and health effects. Sunlight-induced photodegradation of MPs in water is a natural transformation pathway that has been critically reviewed in this work. According to observable photodegradation rates in ultrapure water, MPs were divided into fast, medium and slow groups where half-lives are less than 1 day, 1–10 days and more than 10 days, respectively. The phototransformation fates in diverse water matrices, including nitrate, iron, halides and inorganic ions were summarized. In sunlit environmental water containing dissolved organic matter (DOM) and NO3–, MP photodegradation was likely accelerated. Iron, halides and inorganic ions show both acceleration and inhibition effects on MPs photolysis. The main mechanism of phototransformation was revealed to involve radical species, mostly hydroxyl radicals, attacking MPs. For MP photoproducts, sunlight could increase or decrease the toxicity of the product compared to that of the parent MP. There is a risk that MP phototransformation products may still be toxic. Therefore, focusing on the integrated toxicity of solutions, including parent molecules and photoproducts, is more important in future study.

83. 题目: Halohydrin dehalogenase immobilization in magnetic biochar for sustainable halocarbon biodegradation and biotransformation
文章编号: N22061803
期刊: Environmental Technology & Innovation
作者: Qifa Jiang, Ruiqin Fang, Ijaz Gul, Lizhu Aer, Yaokun Zhao, Jia Guo, Lixia Tang
更新时间: 2022-06-18
摘要: Regarding the fact that halohydrin dehalogenase (HHDH) displays great potential for both biotransformation and biodegradation, developing immobilized HHDH that is suitable for those applications will be of great importance. Herein, the functionalized magnetic biochar was prepared for efficient enzyme immobilization, easy separation, and reuse. The immobilized halohydrin dehalogenase (HheC) was characterized using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM). The results showed that the relative enzyme activity retention was 85% upon immobilization in biochar (HheC-N-MBC600). After 70 days of storage at 4 °C, the HheC-N-MBC600 retained 50% of its initial activity, while only 8% of the activity was retained for the free enzyme. HheC-N-MBC600 displayed a strong organic solvent tolerance as it retained activity above 92% after incubation in 50% organic solvent for 12 h. Moreover, the immobilized catalyst retained more than 70% activity after a consecutive 30 cycles of reuse, indicating excellent recyclability of the immobilized biocatalyst. Moreover, the immobilized enzyme displayed the same enantioselective behavior as the free enzyme. Together with the immobilized epoxide hydrolyase (EchA-MBC600), HheC-N-MBC600 completely converted 1,3-dichloro-2-propanol (1,3-DCP) to a nontoxic compound. Our results showed that the immobilized HheC-N-MBC600 could be a green and industrially viable tool to degrade halogenated compounds and make useful chiral compounds.

84. 题目: Impact of biochar, fertilizers and cultivation type on environmentally persistent free radicals in agricultural soil
文章编号: N22061802
期刊: Environmental Technology & Innovation
作者: Edita Baltrėnaitė-Gedienė, Slawomir Lomnicki, Chuqi Guo
更新时间: 2022-06-18
摘要: Environmentally persistent free radicals (EPFRs) have been considered as emerging contaminants due to their detrimental effects on human health. The adverse health impacts are attributed to oxidative stress induced by EPFRs through the formation of reactive oxygen species (ROS). The biochar pyrolysis process entails the thermal decomposition of organic compounds in the biomass, with the carbonization conditions and feedstock type facilitating the formation of EPFRs. When biochar is used to amend soil, these radicals may promote the formation of ROS, and thus influence the transformation of organic and inorganic contaminants in soil and impact the rhizosphere. Agricultural soils are being amended with biochar to mainly increase carbon content and facilitate the plant growing conditions. Therefore, agricultural soils may become a source of EPFRs. Different cultivation types, addition of fertilisers and variation in biochar input, on the one hand, and presence of metals in soil, biochar and fertilizers, on the other hand, provide different conditions for EPFRs formation, accumulation and fate in agricultural soils, having different impact on soil quality and human health. The paper will present the first studies of EPFRs behaviour in agricultural soil with different input of biochar, cultivation types and periods of time.

85. 题目: Mercury deposition in the western tropical South Atlantic during the last 70 ka
文章编号: N22061801
期刊: Palaeogeography, Palaeoclimatology, Palaeoecology
作者: Bernardo S Chede, Igor M Venancio, Thiago S Figueiredo, Ana Luiza S Albuquerque, Emmanoel Vieira Silva-Filho
更新时间: 2022-06-18
摘要: Mercury is released via natural and anthropogenic sources. Atmospheric deposition via dry and wet deposition is the main source of mercury to the continents and oceans. In the oceans, organic matter is the primary driver of mercury accumulation in marine sediments. Previous studies reported that mercury is sensitive to past climate changes and that global and regional climatic factors can control its environmental dynamics. Here, we used sediment core M125–95-3 collected at the western tropical South Atlantic to investigate mercury deposition and accumulation changes in the marine realm over the last 70 ka. Our records show higher concentration during the glacial period than in the interglacial period due to increased atmospheric dust. On millennial-scale events, the increased residence time of North Atlantic Deep Water enhanced the regenerative scavenging of mercury, which reduced mercury concentration in M125–95-3 core. In addition, the dilution effect might have reduced the mercury concentration further during Heinrich stadials due to increased terrigenous input via the São Francisco River. Altogether, the results suggest a strong influence of deep ocean circulation on the deposition and accumulation of mercury in marine sediments in the western tropical South Atlantic on millennial timescales, highlighting long-term oceanic processes that act on the geochemical cycle of mercury.

86. 题目: Carboxy-functionalized sludge-derived biochar for efficiently activating peroxymonosulfate to degrade bisphenol A
文章编号: N22061712
期刊: Separation and Purification Technology
作者: Meng Li, Dongya Li, Zeyu Guan, Qianqian Xu, Yintao Shi, Dongsheng Xia
更新时间: 2022-06-17
摘要: Oxygenated functional groups (OFGs) such as carbonyl groups (C=O) on the surface of biochar have been regarded as the main reactive sites to activate peroxymonosulfate (PMS), and their catalytic mechanisms have become the key to the research of biochar modification. Herein, sludge-derived biochar (SBC) was surface modified by acetate to gain more OFGs for enhancing the activation of PMS. The removal ability of ASBC-50/PMS system for bisphenol A (BPA) was superior to SBC/PMS system due to the increase of carboxyl groups (-COOH) content on the acetate-modified SBC (ASBC-50). ASBC-50/PMS system was well applied in complex water bodies and exhibited its excellent stability. 1O2 was proven to be the main reactive oxygen species for the removal of BPA. The results of XPS demonstrated that -COOH groups played a vital part in the activation of PMS. This finding provided new insights into the surface modification and functional groups recombination for biochar.

87. 题目: Renewable energy powered membrane technology: Implications of adhesive interaction between membrane and organic matter on spontaneous osmotic backwash cleaning
文章编号: N22061711
期刊: Water Research
作者: Yang-Hui Cai, Akhil Gopalakrishnan, Kaumudi Pradeep Deshmukh, Andrea I Schäfer
更新时间: 2022-06-17
摘要: Organic matter (OM) in surface and ground waters may cause membrane fouling that is laborious to clean once established. Spontaneous osmotic backwash (OB) induced by solar irradiance fluctuation has been demonstrated for early mineral scaling/organic fouling control in decentralised small-scale photovoltaic powered-nanofiltration/reverse osmosis (PV-NF/RO) membrane systems. However, various OM types will interact differently with membranes which in turn may affect the effectiveness of OB. This work evaluates the suitability of spontaneous OB cleaning for eleven OM types (covering low-molecular-weight organics (LMWO), humic substances, polyphenolic compounds and biopolymers) regarding adhesive interactions with NF/RO membranes. The adhesive interactions were quantified by an asymmetric flow field-flow fractionation coupled with an organic carbon detector (FFFF-OCD). The underlying mechanism of DOM-membrane adhesive interactions affecting OB cleaning was elucidated. The results indicate that humic acid (a typical humic substance) and tannic acid (a typical polyphenolic compound) induced stronger adhesive interaction with NF/RO membranes than biopolymers and LMWO. When the mass loss of an OM due to adhesion was below a critical range, the spontaneous OB is most effective (>85% flux recovery); and above this range, the OB becomes ineffective (<50% flux recovery). Polyphenolic compounds and humic substances resulted in lower OB cleaning efficiency, due to their higher aromatic content, enhancing hydrophobic interactions and hydrogen bonding. Calcium-facilitated adhesion of some OM types (such as humic substances, polyphenolics and biopolymers) increased irreversible organic fouling potential and weakened OB cleaning, which was verified by both FFFF-OCD and membrane filtration results. This work provides a guidance to formulate strategies to enhance spontaneous OB cleaning, such as first identifying the adhesion of OM in feedwater (surface water/groundwater) using FFFF-OCD, and then removing “sticky” OM using suitable pre-treatment processes.

88. 题目: Enhanced metal bioleaching mechanisms of extracellular polymeric substance for obsolete LiNixCoyMn1-x-yO2 at high pulp density
文章编号: N22061710
期刊: Journal of Environmental Management
作者: Jia Wang, Yanchao Cui, Huichao Chu, Bingyang Tian, Huimin Li, Mingshun Zhang, Baoping Xin
更新时间: 2022-06-17
摘要: Harmful chemicals present in electric vehicle Li-ion batteries (EV LIBs) can limit the pulp density of bioleaching processes using Acidithiobacillus sp. to 1.0% (w/v) or lower. The strong enhancing mechanisms of extracellular polymeric substances (EPS) on the bioleaching of metals from spent EV LIBs at high pulp density (4% w/v) were studied using bio-chemical, spectroscopic, surface structure imaging and bioleaching kinetic methods. Results demonstrated that the added EPS significantly improved bioleaching efficiency of Ni, Co and Mn improved by 42%, 40% and 44%, respectively. EPS addition boosted the growth of cells under adverse conditions to produce more biogenic H+ while Fe3+ and Fe2+ were adsorbed by the biopolymer. This increased Li extraction by acid dissolution and concentrated the Fe3+/Fe2+ cycle via non-contact mechanisms for the subsequent contact bioleaching of Ni, CO and Mn at the EV LIB-bacteria interface. During the leaching process, added EPS improved adhesion of the bacterial cells to the EV LIBs, and the resultant strong interfacial reactions promoted bioleaching of the target metals. Hence, a combination of non-contact and contact mechanisms initiated by the addition of EPS enhanced the bioleaching of spent EV LIBs at high pulp density.

89. 题目: Interlinkages between soil properties and keystone taxa under different tillage practices on the North China Plain
文章编号: N22061709
期刊: Applied Soil Ecology
作者: Xueqing Liu, Hongrun Liu, Danyang Ren, Churong Liu, Yushi Zhang, Senqi Wang, Zhaohu Li, Mingcai Zhang
更新时间: 2022-06-17
摘要: Revealing the role of keystone taxa in maintaining community structure and driving soil properties is crucial for estimating agri-soil quality and microbial function. However, it is still unclear that how tillage practices mediated the associations between keystone taxa and soil properties to affect soil quality. Hence, this study aimed to investigate the influences of no tillage (NT), conventional tillage (CT), and plow tillage (PT) on soil microbial community structure, co-occurrence pattern, and keystone taxa, as well as the correlations between keystone taxa and soil properties. Compared with NT, CT and PT exhibited lower soil organic carbon (SOC), bulk density (BD), and mean weight diameter, as well as higher cumulative carbon mineralization (Cm). Bacterial diversity and richness were decreased under PT. A total of 58 keystone taxa were identified in the co-occurrence network and 35 genera were significantly separated by tillage practices. Most cellulolytic, chitinolytic, and nitrobacterium genera involved in decomposing complex soil organic matter were abundant under PT. Soil quality index (SQI) of the three tillage practices were in the following order: NT > CT > PT, while the Cm and SOC had greater communalities in SQI. Structural equation model (SEM) further indicated that tillage practices affected soil quality by mediating bacterial diversity and keystone taxa. Additionally, network analysis and SEM indicated that keystone taxa were significantly driven by SOC, Cm, and BD. Overall, the study findings suggested that keystone taxa might serve as biomarkers of agri-soil quality, and healthy farmland ecosystems might be obtained by targeting these species.

90. 题目: Co-application of biochar and nitrogen fertilizer promotes rice performance, decreases cadmium availability, and shapes rhizosphere bacterial community in paddy soil
文章编号: N22061708
期刊: Environmental Pollution
作者: Li Zhang, Yulei He, Dasong Lin, Yanpo Yao, Ningning Song, Fangli Wang
更新时间: 2022-06-17
摘要: Cadmium (Cd) contamination in soil has posed a great threat to crop safety and yield as well as soil quality. Biochar blended with nitrogen fertilizer have been reported to be effective in remediating Cd-contaminated soil. However, the influence of co-application of biochar and nitrogen fertilizer on the Cd bioavailability, rice yield and soil microbiome remains unclear. In this study, eight different treatments including control (CK), 5% biochar (B), 2.6, 3.5, 4.4 g/pot nitrogen fertilizers (N1, N2 and N3), and co-application of biochar and nitrogen fertilizers (BN1, BN2, BN3) were performed in a pot experiment with paddy soil for observations in an entire rice cycle growth period. Results showed single N increased soil available Cd content and Cd uptake in edible part of rice, while the soil available Cd content significantly decreased by 14.8% and 7.4%–11.1% under the B, BN treatments, and the Cd content in edible part of rice was significantly reduced by 35.1% and 18.5%–26.5%, respectively. Besides, B, N and BN treatments significantly increased the yield of rice by 14.3%–86.6% compared with CK, and the highest yield was gained under BN3 treatment. Soil bacterial diversity indices (Shannon, Chao1, observed species and PD whole tree index) under N2, N3 were generally improved. Cluster analysis indicated that bacterial community structures under BN treatments differed from those of CK and single N treatments. BN treatments enhanced the abundances of key bacterial phylum such as Acidobacteria, positively associated with yield, and increased the abundance of Spirochaetes, negatively correlated to soil available Cd and Cd uptake of rice. Furthermore, the regression path analysis (RPA) revealed that pH, organic matter (OM), alkaline hydrolysis of nitrogen (AHN) and available Cd were the major properties influencing Cd content in edible part of rice. Redundancy analysis (RDA) revealed that pH and available Cd played key role in shaping soil bacterial community. Thus, BN is a feasible practice for the improvements of rice growth and remediation of Cd-polluted soil.

91. 题目: Effects on soil nitrogen and plant production from land applying three types of biosolids to an agricultural field for three consecutive years
文章编号: N22061707
期刊: Soil and Tillage Research
作者: Zheya Lin, G.W. Price, David L Burton, O Grant Clark
更新时间: 2022-06-17
摘要: Land application of biosolids as a source of crop fertilizer and soil organic matter can be viewed as a sustainable approach to maintain soil productivity. Field-based experiments were conducted to examine the effects of three municipal biosolids (composted, liquid mesophilic anaerobically digested, and alkaline treated) on soil nitrogen dynamics and corn response, applied over three years in Nova Scotia, Canada. A total of fifteen treatments were evaluated in this study based on application management (surface vs. incorporation) of biosolids and the application of biosolids at a reduced rate with urea supplementation. Agronomic parameters were measured (corn yield and nitrogen uptake) and examined relative to the amendment rates to develop nutrient use efficiency indices. Our results indicate that soil pH was significantly increased by 1–1.5 pH units in alkaline treated biosolids (ATB) treatments under both application methods compared to liquid mesophilic anaerobically digested biosolids (LMAD), composted biosolids (COMP), urea, and an unamended soil control. The soil and plant responses were greatest for ATB>LMAD>COMP. Average soil mineral nitrogen (SMN) concentrations in surface applied biosolids ranged from 25.1 to 33.28 mg kg-1 in the three years of the study, but greater concentrations (33.27–39.39 mg kg-1) were observed when the biosolids were incorporated. The incorporation of biosolids also increased corn biomass yield by 18–33% and nitrogen uptake by 25–38% compared to the surface applied over three years.

92. 题目: Quinone Moieties Link the Microbial Respiration of Natural Organic Matter to the Chemical Reduction of Diverse Nitroaromatic Compounds
文章编号: N22061706
期刊: Environmental Science & Technology
作者: Osmar Menezes, Kumru Kocaman, Stanley Wong, Erika E Rios-Valenciana, Eliot J Baker, Janet K Hatt, Jianshu Zhao, Camila L Madeira, Mark J Krzmarzick, Jim C Spain, Reyes Sierra-Alvarez, Konstantinos T Konstantinidis, Jim A Field
更新时间: 2022-06-17
摘要: Insensitive munitions compounds (IMCs) are emerging nitroaromatic contaminants developed by the military as safer-to-handle alternatives to conventional explosives. Biotransformation of nitroaromatics via microbial respiration has only been reported for a limited number of substrates. Important soil microorganisms can respire natural organic matter (NOM) by reducing its quinone moieties to hydroquinones. Thus, we investigated the NOM respiration combined with the abiotic reduction of nitroaromatics by the hydroquinones formed. First, we established nitroaromatic concentration ranges that were nontoxic to the quinone respiration. Then, an enrichment culture dominated by Geobacter anodireducens could indirectly reduce a broad array of nitroaromatics by first respiring NOM components or the NOM surrogate anthraquinone-2,6-disulfonate (AQDS). Without quinones, no nitroaromatic tested was reduced except for the IMC 3-nitro-1,2,4-triazol-5-one (NTO). Thus, the quinone respiration expanded the spectrum of nitroaromatics susceptible to transformation. The system functioned with very low quinone concentrations because NOM was recycled by the nitroaromatic reduction. A metatranscriptomic analysis demonstrated that the microorganisms obtained energy from quinone or NTO reduction since respiratory genes were upregulated when AQDS or NTO was the electron acceptor. The results indicated microbial NOM respiration sustained by the nitroaromatic-dependent cycling of quinones. This process can be applied as a nitroaromatic remediation strategy, provided that a quinone pool is available for microorganisms.

93. 题目: Magnetic Nitrogen–Doped Biochar for Adsorptive and Oxidative Removal of Antibiotics in Aqueous Solutions
文章编号: N22061705
期刊: Separation and Purification Technology
作者: Zhuangzhuang Chu, Bin Zheng, Wei Wang, Yongtao Li, Yu Yang, Zhuohong Yang
更新时间: 2022-06-17
摘要: Pollution by antibiotics has received attention worldwide because they are difficult to remove in wastewater. Extensive researches on antibiotics removal using adsorption and advanced oxidation processes has not resulted in ideal and effective methods for widespread implementation. Herein, nickel–containing and nitrogen–doped biochars (Ni@NBCs) are synthesized via polymer–assisted metal deposition and pyrolysis processes. These Ni@NBCs exhibit good adsorption capacities and act as catalysts to activate potassium persulfate (PPS) for producing reactive oxygen species, which react with the broad–spectrum antibiotic sulfachloropyridazine (SCP) in an oxidative degradation process. Experimental results of SCP adsorption confirm that the adsorption process follows pseudo–second–order kinetics and Langmuir isotherm models. Oxidative degradation results show that the constructed heterogeneous Ni@NBC/PPS system has excellent SCP degradation ability with degradation rates exceeding 90% within 40 min under certain conditions. The Ni@NBC also exhibits excellent reusability and durability (> 75% degradation rate after 20 cycles). The catalytic mechanism and possible degradation pathways for SCP removal are proposed. Considering the adsorption and catalytic properties of Ni@NBCs, such materials show great application prospects for antibiotics removal in water environments.

94. 题目: Seasonal and spatial variations in riverine DOC exports in permafrost-dominated Arctic river basins
文章编号: N22061704
期刊: Journal of Hydrology
作者: Shiqi Liu, Ping Wang, Qiwei Huang, Jingjie Yu, Sergey P Pozdniakov, Ekaterina S Kazak
更新时间: 2022-06-17
摘要: Climate warming is accelerating the release of voluminous organic carbon from thawing permafrost into the Arctic Ocean via riverine transport. However, the seasonal variations in riverine dissolved organic carbon (DOC) exports in Arctic river basins with different areal extents of permafrost and how changes in water temperature (Tw) impact seasonal DOC exports are not fully understood. In this study, the concentrations, ages and seasonality of riverine DOC in the estuaries of six major Arctic rivers (Ob, Yenisei, Lena, Kolyma, Yukon and Mackenzie) were analysed using Arctic Great Rivers Observatory (ArcticGRO) datasets from 2003 to 2019. The results showed that DOC concentrations generally increased with the increases in the streamflow, but always dropped to the minimum with the oldest Δ14C-DOC ages (as old as 1650 years BP) in the freezing period (November–April), when the streamflow originates predominantly from groundwater. During the flood pulse period (May or June), a rapid increase in riverine DOC concentration with younger organic carbon (Δ14C values from -61 to 152‰) was observed, likely associated with snowmelt-dominated runoff regimes (lower δ18O-H2O of approximately -20.4±1.6‰). During the ice-free period (June–September), DOC concentrations decreased due to the enhanced dilution of streamflow from precipitation. In the Lena and Kolyma River basins with large areal extents of continuous permafrost, over 70% of DOC flux exported during the ice-free period originated from DOC sources from ∼410 years and ∼ 230 years BP to the present, respectively; this suggests that greater permafrost extents restrict the release of older DOC into rivers. However, riverine DOC exports likely respond positively to changes in Tw during the ice-free period. In addition, such a positive response is likely to be enhanced in basins with larger percentages of sporadic permafrost, thicker active layers, more precipitation and less soil organic carbon. Ultimately, under a warming climate, riverine DOC exports are expected to rise with increasing river water temperatures.

95. 题目: Effects of long-term organic matter application on soil carbon accumulation and nitrogen use efficiency in a double-cropping rice field
文章编号: N22061703
期刊: Environmental Research
作者: Haiming Tang, Kaikai Cheng, Lihong Shi, Chao Li, Li Wen, Weiyan Li, Mei Sun, Geng Sun, Zedong Long
更新时间: 2022-06-17
摘要: Increasing soil carbon (C) sequestration in paddy field and improving rice nitrogen use efficiency (NUE) are vital for sustainable agriculture and environmental protection. It was a benefit practice for achieving these goals by taken rice straw and organic manure managements. However, there is still need to further investigate the effects of different long-term fertilizer managements on soil C sequestration and NUE under the double-cropping rice system in southern of China. Therefore, the effects of different long-term (36-years) fertilizer practices on soil C sequestration and NUE under the double-cropping rice system in southern of China were investigated in the present paper. The field experiment was included four different fertilizer treatments: chemical fertilizer alone (MF), rice straw residue and chemical fertilizer (RF), 30% organic manure and 70% chemical fertilizer (OM), and without fertilizer input as a control (CK). This result indicated that soil C content at plough layer in paddy field with RF and OM treatments were increased, compared with MF and CK treatments. Besides input C directly into paddy field, soil original organic C accumulation with RF and OM treatments were increased by 1.54% and 3.01%, compared with MF treatment. This result indicated that soil TOC content increase rate and annual topsoil organic C sequestration rate in paddy field with RF and OM treatments increased by 55.56%, 88.89% and 48.05%, 76.62%, compared with MF treatment, respectively. Compared with MF treatment, NUE with RF and OM treatments increased by 10.43% and 22.61%, respectively, mainly due to increasing soil organic C. Grain yield of double-cropping rice with RF and OM treatments increased by 1009.5 and 1166.5 kg ha−1, compared with MF treatment, respectively. This result indicated that there was significantly correlation between NUE/NUENPK and TOC content with RF and OM treatments, at early rice and late rice growth seasons. Therefore, it was benefit practice for increasing soil carbon sequestration and improving rice NUE in the double-cropping rice system with long-term application of rice straw and organic manure managements.

96. 题目: Ball milling-assisted preparation of N-doped biochar loaded with ferrous sulfide as persulfate activator for phenol degradation: Multiple active sites-triggered radical/non-radical mechanism
文章编号: N22061702
期刊: Applied Catalysis B: Environmental
作者: Jianhua Qu, Yuan Xu, Xiubo Zhang, Mingze Sun, Yue Tao, Xinmiao Zhang, Guangshan Zhang, Chengjun Ge, Ying Zhang
更新时间: 2022-06-17
摘要: Designing Fe-carbon catalyst with multiple active sites for persulfate (PS) activation to water purification is challenging. Herein, nitrogen-doped biochar (NBC) loaded with ferrous sulfide (FeS) was synthesized via two-step ball milling. In FeS@NBCBM/PS system, both electron transfer process and reactive oxygen species (ROSs) including SO4⋅−, O⋅H, O2•− and 1O2 contributed to phenol degradation. Surface-bound S(II) not only interacted with PS for generating SO4•−, but also accelerated Fe(III)/Fe(II) circulation by reducing Fe(III). NBC was favorable for phenol adsorption and exposure of oxygen-containing groups, graphitic and pyridinic N active sites, which mediated electron transfer or ROSs formation. Owing to multiple active sites, this system fast achieved almost complete phenol degradation with excellent adaptability to wide pH range of 3-9, high anti-interference capacity to coexisting substances, and was efficient to various water matrices. Furthermore, phenol degradation pathways were elucidated by DFT calculations with intermediate products showing lower toxicity, demonstrating great potentials of proposed system.

97. 题目: Removal of neonicotinoid pesticides by adsorption on modified Tenebrio molitor frass biochar: Kinetics and mechanism
文章编号: N22061701
期刊: Separation and Purification Technology
作者: Ying Shi, Saier Wang, Man Xu, Xinli Yan, Junbiao Huang, Hong-wei Wang
更新时间: 2022-06-17
摘要: Neonicotinoid pesticides (NEOs) are the most widely used insecticides in the world and pose a serious threat to ecological systems. Thus, the development of an efficient and sustainable technique for their removal is urgently needed. In this study, a novel biochar was prepared by pyrolysis of Tenebrio molitor frass and activated with KOH at 650 (TMFBC-650A), 750 (TMFBC-750A) and 850 ℃ (TMFBC-850A). Among them, TMFBC-750A showed the best adsorption performance, and the adsorption capacities for thiacloprid (THI), nitenpyram (NIT) and dinotefuran (DIN) were 155.08 mg·g-1, 195.86 mg·g-1, 325.81 mg·g-1, respectively. The isotherms for the adsorption of NIT and THI fit the Langmuir model quite well, while DIN fits the Freundlich model. Moreover, the adsorption of THI, NIT and DIN was well fitted by the pseudofirst-order kinetic model. The physicochemical characterization analysis demonstrated that the adsorption process of NEOs by TMFBC might be mainly controlled by micropore filling, π-π electron donor-acceptor interactions and functional group interactions (H-bonding, covalent bonding and hydrophobic interactions). Additionally, the thermodynamic parameters suggested that NEO adsorption in this work was a spontaneous, endothermic and randomly increasing process. TMFBC also exhibited a high selective adsorption capacity regardless of solution pH and inorganic ion strength concentrations. The regenerated TMFBC (via synergistic ultrasound/ethanol) could sustainably and efficiently absorb NEOs in reuse cycles, suggesting that TMFBC has excellent reusability and stability. These results indicated that TMFBC can be a potential and sustainable adsorbent for neonicotinoid pesticide removal.

98. 题目: Insights on ball milling enhanced iron magnesium layered double oxides bagasse biochar composite for ciprofloxacin adsorptive removal from water
文章编号: N22061611
期刊: Bioresource Technology
作者: Jiayi Tang, Yongfei Ma, Song Cui, Yongzhen Ding, Jinyao Zhu, Xi Chen, Zulin Zhang
更新时间: 2022-06-16
摘要: Both ciprofloxacin (CIP) and sugarcane bagasse have brought enormous pressure on environmental safety. Here, an innovative technique combining Fe-Mg-layered double oxides and ball milling was presented for the first time to convert bagasse-waste into a new biochar adsorbent (BM-LDOs-BC) for aqueous CIP removal. The maximum theoretical adsorption capacity of BM-LDOs-BC reached up to 213.1 mg g-1 due to abundant adsorption sites provided by well-developed pores characteristics and enhanced functional groups. The results of characterization, data fitting and environmental parameter revealed that pore filling, electrostatic interactions, H-bonding, complexation and π-π conjugation were the key mechanisms for CIP adsorptive removal. BM-LDOs-BC exhibited satisfactory environmental safety and outstanding adsorption capacity under various environmental situations (pH, inorganic salts, humic acid). Moreover, BM-LDOs-BC possessed excellent reusability. These superiorities illustrated that BM-LDOs-BC was a promising adsorbent and created a new avenue for rational placement of biowaste and high-efficiency synthesis of biochar for antibiotic removal.

99. 题目: Solution NMR investigation of phytic acid adsorption mechanisms at the calcite-water interface
文章编号: N22061610
期刊: Science of The Total Environment
作者: Ai Chen, Lingyang Zhu, Yuji Arai
更新时间: 2022-06-16
摘要: As one of the most abundant organic phosphorus (P) species in soils, phytic acid could serve as a mineralizable P reservoir in soils and sediments. It has been widely acknowledged that the adsorption of phytic acid to soil minerals retards P mineralization in soils. However, the adsorption mechanisms of phytic acid in the minerals are not clearly understood. Using solution 31P NMR and 1H-31P 2D NMR, the adsorption mechanism of phytic acid was investigated at the calcite-water interface at pH 6 and 8. Maximum phytic acid adsorption reached 3.07 mmol/g, 2.60 mmol/g, 2.39 mmol/g at pH 6, 8, and 9.5, respectively. The presence of outer-sphere surface complex was evident by a lack of significant change in zeta-potential of phytic acid reacted calcite. Solution NMR analysis showed a fast exchange process between adsorbed and unreacted phytic acid at the mineral surface on an NMR time scale, also indicating the outer-sphere complexation mechanism at both pH values. Interestingly, a more active role of P5 and P4,6 in binding with calcite surface was observed at pH 6. Adsorbed phytic acid on the calcite surface should be labile and is not limiting P mineralization in the terrestrial environment.

100. 题目: Global organic carbon burial during the Toarcian oceanic anoxic event: Patterns and controls
文章编号: N22061609
期刊: Earth-Science Reviews
作者: David B Kemp, Guillaume Suan, Alicia Fantasia, Simin Jin, Wenhan Chen
更新时间: 2022-06-16
摘要: The early Toarcian oceanic anoxic event (T-OAE, ~183 Ma), also known as the Jenkyns Event, was one of the most important hyperthermal events of the Phanerozoic, caused by the large-scale release of carbon from massive volcanism and/or surficial carbon reservoirs. Organic-rich facies record the event in basins worldwide, but the precise controls on organic carbon burial, and the relative importance of this burial as a mechanism of sequestering excess carbon from the Toarcian atmosphere, are uncertain. In this study, we have compiled total organic carbon (TOC) data from 67 lower Toarcian sections to reconstruct the pattern of organic enrichment through the T-OAE. Shallow marine sites dominate the compilation, and rates of organic carbon burial during the T-OAE were low relative to shallow water margins at the present day. Redox was a major control on organic enrichment and burial rates, but the very high TOC (>5%) observed in hydrographically restricted anoxic-euxinic basins in northern Europe and elsewhere were largely a consequence of low sedimentation rates. Globally, organic enrichment and redox conditions were highly variable, but a majority of sites show an increase in TOC at the T-OAE relative to pre-event values. TOC increases were generally highest where deoxygenation was most severe. In anoxic-euxinic marine basins in Europe organic carbon burial rates may have increased ~500% on average during the T-OAE, potentially sequestering an extra ~791 Gt of carbon relative to the same time period immediately prior to the event. Sites outside of Europe and those that remained oxic-suboxic or were dominated by terrestrial organic matter show variable, and often negligible, changes in organic enrichment across the T-OAE. Globally, an extra ~9000 Gt of carbon may have been buried in shallow seas during the T-OAE relative to before the event. Nevertheless, a paucity of data and significant uncertainties mean that the precise amount of excess carbon sequestered during the T-OAE remains uncertain.

 共 16387 条记录  本页 20 条  本页从 81-100 条  5/820页  首页 上一页  1 2 3 4 5 6 7 8 9 10  下一页  末页   

本数据库数据来源自各期刊,所有权归属各期刊。数据仅供分享学习,不作商业用途,特此申明。