Journal of Environmental Sciences
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2022
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IF 6.796
Xinrui Hao,Jie Tang,Xiaoyun Yi,Kun Gao,Qian Yao,Chunhua Feng,Weilin Huang,Zhi Dang
Vivianite is often found in reducing environments rich in iron and phosphorus from organic debris degradation or phosphorus mineral dissolution. The formation of vivianite is essential to the geochemical cycling of phosphorus and iron elements in natural environments. In this study, extracellular polymeric substances (EPS) were selected as the source of phosphorus. Microcosm experiments were conducted to test the evolution of mineralogy during the reduction of polyferric sulfate flocs (PFS) by Shewanella oneidensis MR-1 ( S. oneidensis MR-1) at EPS concentrations of 0, 0.03, and 0.3 g/L. Vivianite was found to be the secondary mineral in EPS treatment when there was no phosphate in the media. The EPS DNA served as the phosphorus source and DNA-supplied phosphate could induce the formation of vivianite. EPS impedes PFS aggregation, contains redox proteins and stores electron shuttle, and thus greatly promotes the formation of minerals and enhances the reduction of Fe(III). At EPS concentration of 0, 0.03, and 0.3 g/L, the produced HCl-extractable Fe(II) was 107.9, 111.0, and 115.2 mg/L, respectively. However, when the microcosms remained unstirred, vivianite can be formed without the addition of EPS. In unstirred systems, the EPS secreted by S. oneidensis MR-1 could agglomerate at some areas, resulting in the formation of vivianite in the proximity of microbial cells. It was found that vivianite can be generated biogenetically by S. oneidensis MR-1 strain and EPS may play a key role in iron reduction and concentrating phosphorus in the oligotrophic ecosystems where quiescent conditions prevail.
研究领域:
微生物学
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环境科学
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DOI
PubMed
高影响因子
EUROPEAN JOURNAL OF SOIL SCIENCE
·
2024
·Vol. 75
·期 2
·e13464
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IF 4
Yating Deng,Yun Zhang,Xinxin Zheng,Xiaoyang Cui
Forest fires are a primary driver of biogeochemical processes in ecosystems and affect the soil nutrient balance by altering the distribution of organic matter and associated nutrients as well as the composition and availability of elemental nutrients. We investigated the changes in soils’ phosphorus (P) fractions and the adsorption characteristics of potassium dihydrogen orthophosphate (orthoP) and myo -inositol hexakisphosphate (IHP) at two depths (0–5 and 5–10 cm) in soils from two sites differing in fire severity: long-unburned and heavily burned. Five years after the fire, there were increases in the total P and extractable inorganic P (H 2 O-P, NaHCO 3 -Pi, NaOH-Pi, D.HCl-Pi and C.HCl-Pi) contents. Conversely, there was a decrease in organic P (NaHCO 3 -Po, NaOH-Po and C.HCl-Po). The adsorption of soil for orthoP at a depth of 0–5 cm was dependent on the amount of P supplied by the soil; at low concentrations, heavily burned soil showed a lower adsorption than long-unburned soil. However, at high concentrations, the adsorption of heavily burned soil was significantly larger than that of long-unburned soil. With respect to IHP, the adsorption of long-unburned soil was also more significant at depths of 0–5 cm. The adsorption of both orthoP and IHP of heavily burned soil was significantly higher than that of long-unburned soil at a depth of 5–10 cm. Fire also decreased the binding degree (k 1 ) of soil-P and the solid phase at depths of 0–5 and 5–10 cm. The increase in P adsorption capacity outweighed the addition of P from ash, resulting in less leaching in heavily burned areas and minimizing P loss. Overall, forest fires significantly affect the adsorption characteristics and P fractions of soil, specifically orthoP and IHP, during the initial stage of postfire recovery. These effects are closely related to the direct influences of iron oxide, soil organic matter and aluminium oxide in the soil and may even produce relatively long-term effects on the P recycling process of the entire ecosystem.
研究领域:
生态学
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土壤学
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DOI
高影响因子
GEODERMA
·
2017
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IF 4.036
Dasheng Sun,Qingfang Bi,Huaping Xu,Kejie Li,Xipeng Liu,Jun Zhu,Qichun Zhang,Chongwei Jin,Lingli Lu,Xianyong Lin
Soil drying-rewetting can remarkably affect phosphorus (P) transformation, and thus, alter P distribution among P pools; however, little is known about the effect of the degree of drying before rewetting on labile P fractions and the bioavailability of organic P (P o ). In this study, soils with distinct physico-chemical properties were allowed to desiccate to 5%, 10%, 20%, 30%, and 40% water holding capacity (WHC), and soils maintained at 50% WHC were used as controls, and the bicarbonate-extractable P and hydrolyzable P o fractions were analyzed after 5 h of rewetting. Bicarbonate-extractable P o accounted for 33.3–56.4% of extractable total P, and hydrolyzable P o constituted 34.4–79.7% of extractable P o . For extractable P o , 7.7–29.9% was labile monoester P, 6.5–14.9% was diester P, and 17.8–36.5% was phytate-like P. Bicarbonate-extractable inorganic P and P o contents were not affected by 20–40% WHC treatments, but increased by 26.3–48.1% and 5.7–52.9%, respectively, when the soils were dried to 5% WHC. Similarly, labile monoester, diester, and phytate-like P contents increased by 12.5–89.8%, 0–65.2%, and 24.6–65.6%, respectively, in 5% WHC soils. Pearson's correlation analyses showed that the relative increases in bicarbonate-extractable inorganic P and phytate-like P, following extreme drought, were positively correlated with soil organic carbon , oxalate-extractable aluminum (Al), and iron (Fe), suggesting regulatory roles of organic matter and Al/Fe oxides in P transformation during soil drying-rewetting. Taken together, our results suggest that extreme drought events before rainfall or irrigation facilitate an increase in the level of labile P, including considerable proportions of hydrolyzable P o fractions, potentially posing a substantial threat to water bodies in the context of climate change .
研究领域:
生态学
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环境科学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·Vol. 14
·期 1
·120955
·
IF 7.2
Yingchao Li,Juntan Wang,Zhanyu Guo,Xiaofang Ouyang,Peng Ju,Hua Yin
This study presents a novel FeMg-layered double hydroxide (LDH) modified biochar composite (LB) designed to synergistically address phosphate recovery from wastewater and heavy metal immobilization in contaminated soil. The composite exhibits an exceptional phosphate adsorption capacity of 25.02 mg/g, representing a 169.00 % increase compared to pristine biochar. The improved performance results from precipitation and anion exchange within the LDH layers. And the competitive adsorption tests further confirm that LB better retains phosphate in simulated wastewater. When repurposed as a soil amendment, phosphate-laden LB (P-LB) demonstrates remarkable heavy metal immobilization efficiencies, achieving 41.23 % Pb, 30.52 % Cu and 25.63 % As immobilization at a 1.0 % dosage, representing an 18.70–26.42 % improvement over LB. Beyond its metal stabilization capabilities, P-LB effectively enhances soil phosphorus cycling, increasing total phosphorus by 14.41 % and bioavailable phosphorus by 9.02 %. Furthermore, the remediated soil exhibits significantly enhanced enzymatic activity, with urease and sucrase activities increasing by 21.38 % and 380.10 %, respectively. Pot experiments confirm the agronomic benefits of P-LB, demonstrating a 68.16 % increase in plant height and a 39.27 % increase in biomass accumulation in the remediated soil. This integrated approach, leveraging LDH-phosphate synergy, not only achieves phosphate recovery in sewage but also realizes metal immobilization and soil fertility remediation in contaminated soil.
研究领域:
环境科学
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土壤修复学
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环境污染控制
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环境功能材料
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农业环境学
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生物地球化学
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废物资源化
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2024
·
IF 0
Zhang Zekun,Zhao Le,Yang Jie,Pang Jiayin,Lambers Hans,He Honghua
Antibiotic contamination in soil has become a major concern worldwide. At present, it is not clear how two co-existed antibiotics with environmentally relevant concentrations would affect soil bacterial community structure, the abundances of antibiotic resistance genes (ARGs) and functional genes, and whether the effects of antibiotics would differ between rhizosphere and bulk soil. We conducted a greenhouse pot experiment to grow maize in a loess soil treated with oxytetracycline (OTC) or sulfadiazine (SDZ) or both at an environmentally relevant concentration (1 mg kg −1 ) to investigate the effects of OTC and SDZ on the rhizosphere and bulk soil bacterial communities, abundances of ARGs and carbon (C)-, nitrogen (N)-, and phosphorus (P)-cycling functional genes, and on plant growth and plant N and P nutrition. The results show that the effects of environmentally relevant concentrations of OTC and SDZ on bacterial communities and abundances of ARGs and functional genes differ between maize rhizosphere and bulk soil. The effects of two antibiotics resulted in a higher absolute abundances of accA , tet(34) , tnpA-04 , and sul2 in the rhizosphere soil than in the bulk soil and different bacterial community compositions and biomarkers in the rhizosphere soil and the bulk soil. However, OTC had a stronger inhibitory effect on the abundances of a few functional genes in the bulk soil than SDZ did, and their combination had no synergistic effect on plant growth, ARGs, and functional genes. The role of co-existed OTC and SDZ decreased shoot height and increased root N concentration. The results demonstrate that environmentally relevant concentrations of antibiotics shift soil microbial community structure, increase the abundances of ARGs, and reduce the abundances of functional genes. Furthermore, soil contamination with antibiotics can diminish agricultural production via phytotoxic effects on crops, and combined effects of antibiotics on plant growth and nutrient uptake should be considered.
研究领域:
环境科学
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土壤微生物学
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植物科学
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生态学
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农业
✓ 已验证
产品关联
DOI
PubMed
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