ENVIRONMENTAL POLLUTION
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2021
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IF 8.071
Huan-Qin Li,Ying-Jia Shen,Wen-Lei Wang,Hong-Tao Wang,Hu Li,Jian-Qiang Su
Microplastic (MP) pollution is widespread in various ecosystems and is colonized by microbes that form biofilms with compositions and functions. However, compared with aquatic environments, the soil environment has been poorly studied in terms of the taxonomic composition of microbial communities and the factors influencing the community structure of microbes in the plastisphere. In the present study, a microcosm experiment was conducted to investigate the plastisphere bacterial communities of MP (polyvinyl chloride, PVC) in soils with different pH (4.62, 6.5, and 7.46) and arsenic (As) contents (13 and 74 mg kg −1 ). Bacterial communities in the plastisphere were dominated by Proteobacteria and Firmicutes, with distinct compositions and structures compared with soil bacterial communities. Soil pH and As content significantly affected the plastisphere bacterial communities. Constrained analysis of principal coordinates and a structural equation model demonstrated that soil pH had a stronger influence on the dissimilarity and diversity of bacterial communities than did soil As content. Soil pH affected As speciation in soil and on MP. The concentration of dimethylarsinic acid (DMA) was significantly higher on MP than that in soil, indicating that As methylation occurred on MP. These results suggest that environmental fluctuations govern plastisphere bacterial communities with cascading effects on biogeochemical cycling of As in the soil ecosystems.
研究领域:
环境科学
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微生物学
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生态学
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土壤学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2022
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IF 14.224
Kai Yu,Xiuqiong Yang,Mao Wan,Haowen Jiang,Penghui Shao,Liming Yang,Hui Shi,Xubiao Luo
This study, for the first time, evaluates a novel method for the desorption of contaminants from soil that uses the heat generated by zero-valent iron (ZVI) under low-frequency electromagnetic fields (EMF), and elucidates the specific effects of soil pH upon the process. It was found that the temperature of soil mixed with ZVI could reach up to ∼60 °C within 20 min under the applied EMF, and after 60 min the residual fraction of m-xylene in soil decreased by 86.4% compared to no-ZVI soil. The most efficient desorption of m-xylene occurred at a soil of pH 5. Desorption was related to the net heating capacity of the ZVI particles, which was defined by pH-dependent formation of surface corrosion products. The preservation of metal iron and formation of Fe(II) species was favored for heat generation. Soil pH also affected m-xylene retention and the local thermal conduction from ZVI to m-xylene by regulating the surface properties of fulvic acid and ZVI. This study provides valuable information regarding the impact of pH on the thermal desorption of soil contaminants by ZVI coupled with EMF and illustrates the potential of the method in the remediation of contaminated sites.
研究领域:
环境科学
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土壤化学
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污染控制
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电磁工程
✓ 已验证
DOI
PubMed
高影响因子
CHEMOSPHERE
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2021
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IF 7.086
Haixiao Li,Le Liu
Microplastics are an emerging threat to soils, but little is known about their effects on soil nitrogen (N) and phosphorus (P) cycling. In this study, a three-month soil incubation experiment has been conducted to analyze the effects of polyethene (PE) and polypropylene (PP) microplastics in sizes of 0–1 mm and 1–5 mm on soil available phosphate, nitrate, and ammonium contents under different fertilization regimes. Soil phosphorus and nitrogen availability were continuously determined in-situ by ion-exchange membrane method during the incubation. Microplastic surface chemical composition and the specific surface area were analyzed by FTIR and BET, respectively. The 16s rRNA sequencing of soil bacterial communities as well as soil pH have been determined after the incubation. The results showed that the presence of microplastics could significantly (P < 0.05) decrease soil available phosphate content from 122.61 mg P L −1 to 63.43 mg P L −1 . The addition of PP microplastics could significantly increase soil available ammonium content from 0.94 mg N L −1 to 1.53 mg N L −1 . Since microplastics had undetectable specific surface area and limited effects on soil microorganisms, adsorption and microorganism alteration functions might not be the main drivers of microplastic effects on soil phosphorus and nitrogen.
研究领域:
环境科学
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土壤学
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微生物学
✓ 已验证
DOI
PubMed
高影响因子
Environmental Technology & Innovation
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2021
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IF 5.263
Zhong Lin,Weijian Zhang,Xiaoping Zhu,Weijian Wu,Yijie Chen,Gaoyang Li,Lei Ren,Shuwen Luo,Yucheng Xie,Yongxiang Huang,Xinzi Wang,Zhen Zhen,Dayi Zhang
Di-2-ethylhexylphthalate (DEHP) is a common plasticizer and widely detected in sediments, water and biota. For its strong reproductive toxicity, teratogenicity and poisonousness, many approaches are developed to remediate DEHP-contaminated soils. This study aimed to evaluate the roles of biochar in accelerating DEHP degradation, assess the impacts of biochar pyrolysis temperature on DEHP removal performance, and explore the underlying mechanisms. Biochar had a satisfactory performance in DEHP adsorption and followed a Freundlich isotherm, exhibiting proportional adsorption capabilities to pyrolysis temperature. Biochar amendment significantly accelerated soil DEHP degradation, and the degradation efficiency ranged from 61.4% to 82.2% and increased with biochar pyrolysis temperature. Biochar remarkably changed soil physiochemical properties by increasing soil pH, organic matter and humus. Soil bacterial community was altered with biochar amendment that the relative abundance of Nocardioides , Marinobacter , Rhodococcus and Gramella increased. Our findings suggested that biochar-assisted bioremediation has a huge potential in soil DEHP degradation and pyrolysis temperature is a critical factor affecting the performance. Our work characterize biochar at different pyrolysis temperatures and explored the underlying mechanisms of biochar-assisted DEHP bioremediation, offering both scientific and practical hints for DEHP bioremediation in coastal sediments.
研究领域:
环境科学
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土壤学
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微生物学
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污染控制
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生物修复
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2024
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IF 8.2
Zhiqin Chen,Qizhen Liu,Dan Chen,Yingjie Wu,Yasir Hamid,Qiang Lin,Shijun Zhang,Ying Feng,Zhenli He,Xianyuan Yin,Xiaoe Yang
Plant growth regulators (PGR) and plant growth-promoting bacteria (PGPB) have the potential in phytoremediation of heavy metals (HMs) contaminated soils. However, their sole application may not yield the optimal results, thus necessitating the combined application. The present study aimed to enhance the phytoremediation efficiency of Sedum alfredii Hance ( S. alfredii ) in acidic and alkaline soils through the combination of PGR (Brassinolide, BR) and PGPB ( Pseudomonas fluorescens , P. fluorescens ). The combination of BR and P. fluorescens (BRB treatment) effectively increased the removal efficiency of S. alfredii for Cd, Pb, and Zn by 355.2 and 155.3 %, 470.1 and 128.9 %, and 408.4 and 209.6 %, in acidic and alkaline soils, respectively. Moreover, BRB treatment led to a substantial increase in photosynthetic pigments contents and antioxidant enzymes activities, resulting in a remarkable increase in biomass (86.71 and 47.22 %) and dry mass (101.49 and 42.29 %) of plants grown in acidic and alkaline soils, respectively. Similarly, BRB treatment significantly elevated the Cd (109.4 and 71.36 %), Pb (174.9 and 48.03 %), and Zn levels (142.8 and 104.3 %) in S. alfredii shoots, along with cumulative accumulation of Cd (122.7 and 79.47 %), Pb (183.8 and 60.49 %), and Zn (150.7 and 117.9 %), respectively. In addition, the BRB treatment lowered the soil pH and DTPA-HMs contents, while augmenting soil enzymatic activities, thereby contributing soil microecology and facilitating the HMs absorption and translocation by S. alfredii to over-ground tissues. Furthermore, the evaluation of microbial community structure in phyllosphere and rhizosphere after remediation revealed the shift in microbial abundance. The combined treatment altered the principal effects on S. alfredii HMs accumulation from bacterial diversity to the soil HMs availability. In summary, our findings demonstrated that synergistic application of BR and P. fluorescens represents a viable approach to strengthen the phytoextraction efficacy of S. alfredii in varying soils.
研究领域:
环境科学
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植物修复
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土壤学
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微生物学
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植物生理学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）