1
|
Zhang L, Ali A, Su J, Huang T, Wang Z. Ammonium nitrogen and phosphorus removal by bacterial-algal symbiotic dynamic sponge bioremediation system in micropolluted water: Operational mechanism and transformation pathways. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 947:174636. [PMID: 38992368 DOI: 10.1016/j.scitotenv.2024.174636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 06/28/2024] [Accepted: 07/07/2024] [Indexed: 07/13/2024]
Abstract
Construct a bacteria-algae symbiotic dynamic sponge bioremediation system to simultaneously remove multiple pollutants under micro-pollution conditions. The average removal efficiencies of NH4+-N, PO43--P, total nitrogen (TN), and Ca2+ were 98.35, 78.74, 95.64, and 84.92 %, respectively. Comparative studies with Auxenochlorella sp. sponge and bacterial sponge bioremediation system confirmed that NH4+-N and TN were mainly removed by bacterial heterotrophic nitrification - aerobic denitrification (HN-AD). PO43--P was removed by algal assimilation and the generation of Ca3(PO4)2 and Ca5(PO4)3OH, and Ca2+ was removed by algal electron transfer formation of precipitates and microbially induced calcium precipitation (MICP) by bacteria. Algae provided an aerobic environment for the bacterial HN-AD process through photosynthesis, while respiration produced CO2 and adsorbed Ca2+ to promote the formation of calcium precipitates. Immobilization of Ca2+ with microalgae via bacterial MICP helped to lift microalgal photoinhibition. The bioremediation system provides theoretical support for research on micropolluted water treatment while increasing phosphorus recovery pathways.
Collapse
Affiliation(s)
- Lingfei Zhang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Amjad Ali
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Junfeng Su
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
| | - Tinglin Huang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Zhao Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| |
Collapse
|
2
|
Ma J, Min Y, Su J, Huang T, Ali A, Wang Y, Li X. Simultaneous removal of ammonia nitrogen, phosphate, zinc, and phenol by degradation of cellulose in composite mycelial pellet bioreactor: Enhanced performance and community co-assembly mechanism. ENVIRONMENTAL RESEARCH 2024; 252:118780. [PMID: 38555089 DOI: 10.1016/j.envres.2024.118780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 03/02/2024] [Accepted: 03/22/2024] [Indexed: 04/02/2024]
Abstract
In this experiment, the prepared tea biochar-cellulose@LDH material (TB-CL@LDH) was combined with mycelium pellets to form the composite mycelial pellets (CMP), then assembled and immobilized with strains Pseudomonas sp. Y1 and Cupriavidus sp. ZY7 to construct a bioreactor. At the best operating parameters, the initial concentrations of phosphate (PO43--P), ammonia nitrogen (NH4+-N), chemical oxygen demand (COD), zinc (Zn2+), and phenol were 22.3, 25.0, 763.8, 1.0, and 1.0 mg L-1, the corresponding removal efficiencies were 80.4, 87.0, 83.4, 91.8, and 96.6%, respectively. Various characterization analyses demonstrated that the strain Y1 used the additional carbon source produced by the strain ZY7 degradation of cellulose to enhance the removal of composite pollutants and clarified the principle of Zn2+ and PO43--P removal by adsorption, co-precipitation and biomineralization. Pseudomonas and Cupriavidus were the dominant genera according to the high-throughput sequencing. As shown by KEGG results, nitrification and denitrification genes were affected by phenol. The study offers prospects for the simultaneous removal of complex pollutants consisting of NH4+-N, PO43--P, Zn2+, and phenol.
Collapse
Affiliation(s)
- Jiayao Ma
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Yitian Min
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Junfeng Su
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China.
| | - Tinglin Huang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Amjad Ali
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Yue Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Xuan Li
- College of Environmental Science & Engineering, Yancheng Institute of Technology, Yancheng, 224051, China
| |
Collapse
|
3
|
Escobar M, Ji J, Wang Y, Feng M, Bao C, Ma J, Cui S, Zang S, Zhang J, Zhang W, Chen G, Chen H. Effect of thermal treatment of illite on the bioavailability of copper and zinc in the aerobic composting of pig manure with corn straw. Front Microbiol 2024; 15:1411251. [PMID: 38903784 PMCID: PMC11187081 DOI: 10.3389/fmicb.2024.1411251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Accepted: 05/27/2024] [Indexed: 06/22/2024] Open
Abstract
The large amount of various types of heavy metals in animal manure applied to agricultural field has caused severe threat to the ecosystems of soil environments. In this study, the effect of thermal treatment of illite on the bioavailability of copper (Cu) and zinc (Zn) in the aerobic composting of pig manure with corn straw biochar was investigated. The objectives of this study were to characterize the variations in the bioavailability of Cu and Zn in the aerobic composting of pig manure added with illite treated with high temperatures and to identify the relatively dominant microbes involved in the formation of humus and passivation of heavy metals in pig manure composting based on 16S rRNA high-throughput sequencing analysis. The results showed that in comparison with the raw materials of pig manure, the bioavailability of Zn and Cu in the control and three experimental composting groups, i.e., group I (with untreated illite), group I-2 (with illite treated under 200°C), and group I-5 (with illite treated under 500°C), was decreased by 27.66 and 71.54%, 47.05 and 79.80%, 51.56 and 81.93%, and 58.15 and 86.60%, respectively. The results of 16S rRNA sequencing analysis revealed that in the I-5 group, the highest relative abundance was detected in Fermentimonas, which was associated with the degradation of glucose and fructose, and the increased relative abundances were revealed in the microbes associated with the formation of humus, which chelated with Zn and Cu to ultimately reduce the bioavailability of heavy metals and their biotoxicity in the compost. This study provided strong experimental evidence to support the application of illite in pig manure composting and novel insights into the selection of appropriate additives (i.e., illite) to promote humification and passivation of different heavy metals in pig manure composting.
Collapse
Affiliation(s)
- Maia Escobar
- College of Life Science, Jilin Agricultural University, Changchun, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Ministry of Education, Jilin Agricultural University, Changchun, China
| | - Jiaoyang Ji
- College of Life Science, Jilin Agricultural University, Changchun, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Ministry of Education, Jilin Agricultural University, Changchun, China
| | - Yueru Wang
- College of Life Science, Jilin Agricultural University, Changchun, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Ministry of Education, Jilin Agricultural University, Changchun, China
| | - Meiqin Feng
- College of Life Science, Jilin Agricultural University, Changchun, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Ministry of Education, Jilin Agricultural University, Changchun, China
| | - Changjie Bao
- Key Laboratory of Wetland Ecology and Environment, State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, China
| | - Jianxun Ma
- College of Life Science, Jilin Agricultural University, Changchun, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Ministry of Education, Jilin Agricultural University, Changchun, China
| | - Shijia Cui
- College of Life Science, Jilin Agricultural University, Changchun, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Ministry of Education, Jilin Agricultural University, Changchun, China
| | - Sihan Zang
- College of Life Science, Jilin Agricultural University, Changchun, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Ministry of Education, Jilin Agricultural University, Changchun, China
| | - Jinpeng Zhang
- Key Laboratory of Wetland Ecology and Environment, State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, China
| | - Wei Zhang
- College of Life Science, Jilin Agricultural University, Changchun, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Ministry of Education, Jilin Agricultural University, Changchun, China
| | - Guang Chen
- College of Life Science, Jilin Agricultural University, Changchun, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Ministry of Education, Jilin Agricultural University, Changchun, China
| | - Huan Chen
- College of Life Science, Jilin Agricultural University, Changchun, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Ministry of Education, Jilin Agricultural University, Changchun, China
| |
Collapse
|
4
|
Mu L, Dong R, Wang J, Yue J, Pan L, Song C, Wei Z. The positive effect of the enzyme inducer (MnSO 4) on the formation of humic substance in rice straw composting by stimulating key microorganisms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 923:171460. [PMID: 38442764 DOI: 10.1016/j.scitotenv.2024.171460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 03/01/2024] [Accepted: 03/01/2024] [Indexed: 03/07/2024]
Abstract
This study investigated the impact of adding enzyme inducer (MnSO4) on humic substance (HS) formation during straw composting. The results demonstrated that both enzyme inducer treatment group (Mn) and functional microorganism treatment group (F) led to an increase in the content of HS compared to the treatment group without enzyme inducer and functional microorganism (CK). Interestingly, the enzyme inducer exhibited a higher promoting effect on HS (57.80 % ~ 58.58 %) than functional microbial (46.54 %). This was because enzyme inducer stimulated the growth of key microorganisms and changed the interaction relationship between microorganisms. The structural equation model suggested that the enzyme inducer promoted the utilization of amino acids by the fungus and facilitated the conversion of precursors to humic substance components. These findings provided a direction for improving the quality of composting products from agricultural straw waste. It also provided theoretical support for adding MnSO4 to compost.
Collapse
Affiliation(s)
- Linying Mu
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Runshi Dong
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Jiaqi Wang
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Jieyu Yue
- College of Life Sciences, Tianjin Normal University, Tianjin 300387, China
| | - Lina Pan
- College of Life Sciences, Tianjin Normal University, Tianjin 300387, China
| | - Caihong Song
- School of Life Science, Liaocheng University, Liaocheng 252000, China
| | - Zimin Wei
- College of Life Science, Northeast Agricultural University, Harbin 150030, China; College of Life Sciences, Tianjin Normal University, Tianjin 300387, China.
| |
Collapse
|
5
|
Kou B, Yuan Y, Zhu X, Ke Y, Wang H, Yu T, Tan W. Effect of soil organic matter-mediated electron transfer on heavy metal remediation: Current status and perspectives. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 917:170451. [PMID: 38296063 DOI: 10.1016/j.scitotenv.2024.170451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 01/18/2024] [Accepted: 01/24/2024] [Indexed: 02/05/2024]
Abstract
Soil contamination by heavy metals poses major risks to human health and the environment. Given the current status of heavy metal pollution, many remediation techniques have been tested at laboratory and contaminated sites. The effects of soil organic matter-mediated electron transfer on heavy metal remediation have not been adequately studied, and the key mechanisms underlying this process have not yet been elucidated. In this review, microbial extracellular electron transfer pathways, organic matter electron transfer for heavy metal reduction, and the factors affecting these processes were discussed to enhance our understanding of heavy metal pollution. It was found that microbial extracellular electrons delivered by electron shuttles have the longest distance among the three electron transfer pathways, and the application of exogenous electron shuttles lays the foundation for efficient and persistent remediation of heavy metals. The organic matter-mediated electron transfer process, wherein organic matter acts as an electron shuttle, promotes the conversion of high valence state metal ions, such as Cr(VI), Hg(II), and U(VI), into less toxic and morphologically stable forms, which inhibits their mobility and bioavailability. Soil type, organic matter structural and content, heavy metal concentrations, and environmental factors (e.g., pH, redox potential, oxygen conditions, and temperature) all influence organic matter-mediated electron transfer processes and bioremediation of heavy metals. Organic matter can more effectively mediate electron transfer for heavy metal remediation under anaerobic conditions, as well as when the heavy metal content is low and the redox potential is suitable under fluvo-aquic/paddy soil conditions. Organic matter with high aromaticity, quinone groups, and phenol groups has a stronger electron transfer ability. This review provides new insights into the control and management of soil contamination and heavy metal remediation technologies.
Collapse
Affiliation(s)
- Bing Kou
- College of Urban and Environmental Science, Northwest University, Xi'an 710127, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Ying Yuan
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Xiaoli Zhu
- College of Urban and Environmental Science, Northwest University, Xi'an 710127, China.
| | - Yuxin Ke
- College of Urban and Environmental Science, Northwest University, Xi'an 710127, China
| | - Hui Wang
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Tingqiao Yu
- International Education College, Beijing Vocational College of Agriculture, Beijing 102442, China
| | - Wenbing Tan
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| |
Collapse
|
6
|
Zhang P, Xu L, Su J, Zeng Y, Liu Y, Li X. Simultaneous removal of nitrate, oxytetracycline and copper by ferrous-manganese co-driven immobilized bioreactor. JOURNAL OF HAZARDOUS MATERIALS 2024; 466:133621. [PMID: 38290330 DOI: 10.1016/j.jhazmat.2024.133621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Revised: 01/23/2024] [Accepted: 01/23/2024] [Indexed: 02/01/2024]
Abstract
The treatment of polluted water contaminated by nitrate, antibiotics, and heavy metals is a difficult problem in the current water treatment process. In this study, MnFe2O4 modified illite was mixed with sodium alginate (SA) to prepare a biological carrier illite@MnFe2O4@SA (IMFSA), which was used to immobilize strain Zoogloea sp. MFQ7 and construct a bioreactor. The bioreactor can use sodium acetate as a carbon source as well as ferrous and manganese ions as additional electron donors to achieve efficient nitrate removal. The denitrification capability of bioreactor was considerably enhanced by the addition of illite@MnFe2O4 (IMF) in comparison to SA biological carrier. The bioreactor was able to achieve a nitrate removal efficiency of 97.2% when hydraulic retention time is 5.0 h, C/N ratio is 2.0, and the concentration of Fe2+ and Mn2+ were 5.0 mg L-1. Furthermore, the bioreactor can achieve efficient removal of oxytetracycline (91.8%) and copper (85.6%) through the adsorption by IMF and biological iron-manganese precipitates. High-throughput sequencing results indicated that Zoogloea was successfully immobilized into the biocarrier. According to the KEGG database, it is suggested that the addition of modified IMF enhances denitrification and stimulates the expression of genes associated with the iron-manganese redox cycle.
Collapse
Affiliation(s)
- Peng Zhang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Liang Xu
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Junfeng Su
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
| | - Yuxin Zeng
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Yan Liu
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Xuan Li
- College of Environmental Science & Engineering, Yancheng Institute of Technology, Yancheng 224051, China
| |
Collapse
|
7
|
Akhzari F, Naseri T, Mousavi SM, Khosravi-Darani K. A sustainable solution for alleviating hexavalent chromium from water streams using Lactococcus lactis AM99 as a novel Cr(VI)-reducing bacterium. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 353:120190. [PMID: 38306859 DOI: 10.1016/j.jenvman.2024.120190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 01/03/2024] [Accepted: 01/20/2024] [Indexed: 02/04/2024]
Abstract
Chromium, extensively used in various industries, poses significant challenges due to its environmental impact. The threat of Cr(VI) causes critical concerns in aquatic ecosystems as a consequence of the fluidity of water. The conventional approach for the treatment of effluents containing Cr(VI) is reducing Cr(VI) to low-noxious Cr(III). This research is related to a Gram positive bacterium newly isolated from tannery effluent under aerobic conditions. To characterize functional groups on the isolate, Fourier transform infrared spectroscopy was utilized. The effect of different factors on Cr(VI) bioreduction was investigated, including temperature, initial Cr(VI) concentration, acetate concentration, and Tween 80 surfactant. Under optimal conditions (37 °C and 0.90 g/L sodium acetate), the bioreduction rate of the isolate, identified as Lactococcus lactis AM99, achieved 88.0 % at 300 mg/L Cr(VI) during 72 h (p < 0.05). It was observed that Cr(VI) bioreduction was enhanced by the acetate in both the quantity and intensity, while Tween 80 had no impact on the reaction. The strain AM99 exhibited remarkable characteristics, notably a marginal decrease in growth at elevated concentrations of hexavalent chromium and an exceptional potential to reduce Cr(VI) even at very low biomass levels, surpassing any prior findings in the associated research. Furthermore, The isolate could tolerate 1400 mg/L Cr(VI) in a solid medium. These distinctive features make the isolate a promising and well-suited candidate for remediating Cr(VI)-polluted environments. Additionally, the impact of biogenic extracellular polymer produced by the strain AM99 on reduction was examined at different temperatures.
Collapse
Affiliation(s)
- Farid Akhzari
- Biotechnology Group, Chemical Engineering Department, Tarbiat Modares University, Tehran, Iran
| | - Tannaz Naseri
- Biotechnology Group, Chemical Engineering Department, Tarbiat Modares University, Tehran, Iran
| | - Seyyed Mohammad Mousavi
- Biotechnology Group, Chemical Engineering Department, Tarbiat Modares University, Tehran, Iran; Modares Environmental Research Institute, Tarbiat Modares University, Tehran, Iran.
| | - Kianoush Khosravi-Darani
- Department of Food Technology Research, National Nutrition and Food Technology Research Institute, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| |
Collapse
|
8
|
Liu Z, Dai Y, Zhu H, Liu H, Zhang J. Effects of additive on formation and electron transfer capacity of humic substances derived from silkworm-excrement compost during composting. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 351:119673. [PMID: 38043316 DOI: 10.1016/j.jenvman.2023.119673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 11/14/2023] [Accepted: 11/20/2023] [Indexed: 12/05/2023]
Abstract
Amending biochar or MnO2 is a common strategy to regulate humification during manure composting. However, how these additives affect the formation, spectrum characteristics (UV-vis, FTIR, EEM) of humic substances (HSs) in silkworm-excrement (SE) compost and their electron transfer capacities (ETC) remains unclear. Thus, the SE composting pilot separately added with 10% corncob biochar (CB) (w/w) and 0.5% MnO2 (w/w) was run to investigate the effects. The results revealed that adding 10% CB slightly affected the HA/FA (humic acids/fulvic acids) ratios, UV-vis and FTIR spectra of the final SE-compost HSs and EEM components in the FA, but remarkably improved fulvic-like (C1)/quinone-like (C3) substances and reduced humic-like (C2)/protein-like substances (C4) in the HA. Meanwhile, 0.5% MnO2 had a noticeable positive effect on the aromatization of SE-compost FA and HA but only weak impact on SUVAs and EEM components in these HSs except C4 in the FA. Moreover, 10% CB obviously reduced EAC/EDC of FA and HA in the final SE compost by 31.1%/22.0% and 19.7%/24.0%, while MnO2 improved EDC of these HSs by 6.5%/9.1% (FA/HA). These results showed MnO2 can be used as a useful amendment to enhance the promotion effect of SE-compost HA in the soil remediation other than CB. Further investigation is suggested to focus on the effects of adding MnO2 on SE-compost HSs enhancing soil remediation and its effect on ETC derived from other manure compost.
Collapse
Affiliation(s)
- Zhihao Liu
- Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin, 541004, China; College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China
| | - Yu Dai
- Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin, 541004, China; College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China
| | - Hongxiang Zhu
- Guangxi Modern Industry College of Ecology and Environmental Protection, Guilin University of Technology, Guilin, 541004, China
| | - Hongtao Liu
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Jun Zhang
- Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin, 541004, China; College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China.
| |
Collapse
|
9
|
Xuehan F, Xiaojun G, Weiguo X, Ling Z. Effect of the addition of biochar and wood vinegar on the morphology of heavy metals in composts. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:118928-118941. [PMID: 37922076 DOI: 10.1007/s11356-023-30645-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Accepted: 10/19/2023] [Indexed: 11/05/2023]
Abstract
In the experiment, the morphology of heavy metals (Pb, Cr, Cd, and Ni, HMs) was characterized using flame atomic absorption spectroscopy. In addition, Fourier transform infrared spectroscopy (FTIR) and three-dimensional excitation-emission matrix fluorescence spectroscopy (3D-EEM) were used to characterize the correlation between environmental factors and metal morphology in the rotting compost from several angles. The results showed that the humus treated with wood vinegar solution had a high degree of humification and rich aromatic structure. FTIR spectroscopy confirmed that the degree of humus aromatization gradually increased during the composting process, which enhanced the complexation of humus (HS) with HMs but had less effect on Ni. In addition, the optimum concentration of wood vinegar (WV) was determined to be 1.75%. The results of the study showed that in the Pb passivation treatment group, the proportion of soluble (Red) and exchangeable states (Exc) converted to oxidized (Oxi) and residual states (Res) was 8%, 14%, 6%, 1%, and 12% in the CK, T1, T2, T3, and T4 treatment groups, respectively; in the Cr passivation treatment group, the proportion of Cr-Red and Cr-Exc converted to oxidized and residual states was 31%, 33%, 25%, 29%, and 25%; in the Cd passivation treatment group, the proportions of Cd-Red and Cd-Exc converted to oxidized and residual states were 5%, 15%, 4%, 9%, and 11%, respectively; whereas the Ni treatment group did not show any significant passivation effect. The proportion of Pb-Oxi was relatively stable, Cr-Oxi was converted to Cr-Res, whereas Cd showed the conversion of Cd-Oxi to Cd-Exc. SUVA254 and SUVA280 showed significant positive correlations with Pb-Res, Cr-Res and Ni-Res, and significant positive correlations with moisture content (MC); whereas MC was significantly negatively correlated with each form of HMs. Total potassium (TK), total nitrogen (TN), and both carbon (TOC) were negatively correlated with Pb-Res and Pb-Exc. Structural equation modeling verified the relationship between environmental factors and HMs, and the composting results showed that the addition of biochar (BC) and a higher percentage of WV could increase compost decomposition and passivate HMs to improve its agronomic function.
Collapse
Affiliation(s)
- Fu Xuehan
- College of Mechanical and Electrical Engineering, Tarim University, Arar, 843300, Xinjiang, China
- Department of Education, Key Laboratory of Modern Agricultural Engineering in General Universities, Xinjiang Uygur Autonomous Region, Alar, 843300, Xinjiang, China
| | - Guo Xiaojun
- College of Mechanical and Electrical Engineering, Tarim University, Arar, 843300, Xinjiang, China
- Department of Education, Key Laboratory of Modern Agricultural Engineering in General Universities, Xinjiang Uygur Autonomous Region, Alar, 843300, Xinjiang, China
| | - Xu Weiguo
- College of Mechanical and Electrical Engineering, Tarim University, Arar, 843300, Xinjiang, China
- Department of Education, Key Laboratory of Modern Agricultural Engineering in General Universities, Xinjiang Uygur Autonomous Region, Alar, 843300, Xinjiang, China
| | - Zhou Ling
- College of Mechanical and Electrical Engineering, Tarim University, Arar, 843300, Xinjiang, China.
- Department of Education, Key Laboratory of Modern Agricultural Engineering in General Universities, Xinjiang Uygur Autonomous Region, Alar, 843300, Xinjiang, China.
| |
Collapse
|