An experiment with seven N, P, K-fertilizer treatments, i.e., control (no fertilizer), NP, NK, PK, NPK, NP2K, and NPK2 where P2 and K2 indicate double amounts of P and K fertilizers respectively, was conducted to exam...An experiment with seven N, P, K-fertilizer treatments, i.e., control (no fertilizer), NP, NK, PK, NPK, NP2K, and NPK2 where P2 and K2 indicate double amounts of P and K fertilizers respectively, was conducted to examine the effect of long-term continuous application of chemical fertilizers on microbial biomass and functional diversity of a black soil (Udoll in the USDA Soil Taxonomy) in Northeast China. The soil microbial biomass C ranged between 94 and 145 mg kg-1, with the NK treatment showing a lower biomass; the functional diversity of soil microbial community ranged from 4.13 to 4.25, with an increasing tendency from control to double-fertilizer treatments, and to triple-fertilizer treatments. The soil microbial biomass, and the microbial functional diversity and evenness did not show any significant differences among the different fertilizer treatments including control, suggesting that the long-term application of chemical fertilization would not result in significant changes in the microbial characteristics of the black soil.展开更多
Heavy metal contamination of soils through anthropogenic activities is a widespread and serious problem confronting scientists and regulators throughout the world. In this study we investigated the distribution, chemi...Heavy metal contamination of soils through anthropogenic activities is a widespread and serious problem confronting scientists and regulators throughout the world. In this study we investigated the distribution, chemical species and availability of lead, zinc, cadmium and copper in nine surface(0 to 20 cm) soils from near an abandoned lead/zinc mine tailings located in Shaoxing, Zhejiang, China. Total heavy metal contents ranged from 5271 to 16369 mg/kg for Pb, 387 to 1221 mg/kg for Zn, 3.0 to 9.3 mg/kg for Cd and 65 to 206 mg/kg for Cu. In general, all heavy metals exceeded China National Standards for Soil Environmental Quality of Heavy Metals by a factor of 3-65 times. Comparison of the heavy metal concentrations(Pb, Zn, Cd and Cu) with clay content revealed a strongly significant relationship while significant relationship( P 〈 0.001 ) was also obtained between Cd + Zn and Pb + Cu. Solid phase speciation of the soils using Tessier procedure showed that the heavy metals were distributed in the order: residual 〉〉 organically complexed-Fe-Mn oxides occluded 〉 carbonate bound 〉 exchangeable 〉 water soluble. In the organic matter fraction, the ratio of Pb(29.1% ) to its total concentration in the soils was higher than those of Zn(4.70% ), Cd(3.16% ) and Cu(9.50% ). The percentages of the water soluble and the exchangeable fractions of Pb(1.80% ) and Cd(2.74% ) were markedly greater than those of Zn(0.10% ) and Cu(0.15% ), suggesting that Pb and Cd are relatively more mobile and hence more toxic in the contaminated soils. Strongly significant relationships between H20-Pb, H20-Zn and H20-Cu, strong positive correlations between H20-Pb, H20-Zn, H20-Cu and organic matter in soil were found. The content of H20-Pb, H20-Zn, H20-Cu was negatively correlated with pH values. The similar negative relationships between pH values and exchangeable heavy metals were also recorded. It is suggested that increasing soil pH or liming the soil could decrease bioavailability of heavy metals in the soil.展开更多
Ecological effects of crude oil residues on weed rhizospheres are still vague. The quantitative and diversity changes and metabolic responses of soil-bacterial communities in common dandelion (Taraxacum officinale),...Ecological effects of crude oil residues on weed rhizospheres are still vague. The quantitative and diversity changes and metabolic responses of soil-bacterial communities in common dandelion (Taraxacum officinale), jerusalem artichoke (Silphiurn perfoliatum L.) and evening primrose (A colypha australis L.) rhizospheric soils were thus examined using the method of carbon source utilization. The results indicated that there were various toxic effects of crude oil residues on the growth and reproduction of soil bacteria, but the weed rhizospheres could mitigate the toxic effects. Total heterotrophic counting colony-forming units (CFUs) in the rhizospheric soils were significantly higher than those in the non-rhizospheric soils. The culturable soil-bacterial CFUs in the jerusalem artichoke (S. perfoliatum) rhizosphere polluted with 0.50 kg/pot of crude oil residues were almost twice as much as those with 0.25 kg/pot and without the addition of crude oil residues. The addition of crude oil residues increased the difference in substrate evenness, substrate richness, and substrate diversity between non-rhizospheric and rhizospheric soils of T. officinale and A. australis, but there was no significant (p〉0.05) difference in the Shannon's diversity index between non-rhizospheric and rhizospheric soils of S. perfoliatum. The rhizospheric response of weed species to crude oil residues suggested that S. perfoliatum may be a potential weed species for the effective plant-microorganism bioremediation of contaminated soils by crude oil residues.展开更多
A study was conducted to determine the relationships between agronomic soil test P and environmental soil test P in three soils predominately distributing in three typical agricultural production areas of China. Soil ...A study was conducted to determine the relationships between agronomic soil test P and environmental soil test P in three soils predominately distributing in three typical agricultural production areas of China. Soil P was analyzed using Bray-1 (BP), Olsen (OP), and Mehlich-3 (MP) methods as agronomic tests, and using Fe-oxide impregnated filter paper (FeP), anion-exchange resin membrane (RP), and water (WP) as environmental tests. There were linear relationships between soil P extractable with all the tests evaluated. The regression coeffcients, R2, ranged from 0.8164 to 0.9409 between each two of the agronomic soil test P, and ranged from 0.4702 to 0.8990 between each two of the environmental soil test P, when the three soils were considered separately. When soil test P was analyzed across all the three soils, the highest regression R2 was found between OP and MP (0.7940) amongst agronomic soil test P, and between FeP and RP amongst environmental soil test P (0.8842). While all of the three agronomic soil test P was linearly related to each of the environmental soil test P across the three soils, strongest relationships were found between OP and environmental soil test P. Agronomic OP may be adopted as an analytical tool for environmental prediction of soil P.展开更多
This research includes two investigations. The first one is a market basket survey of the levels of arsenic (As) and trace elements in bracken fern (Pteridium aquilinum) originated from three countries: South Kor...This research includes two investigations. The first one is a market basket survey of the levels of arsenic (As) and trace elements in bracken fern (Pteridium aquilinum) originated from three countries: South Korea, China and North Korea. The results showed that the mean As concentrations in stems of samples were significantly higher than those in leaves. As concentrations in all samples did not exceed food safety limits for vegetables. Generally, concentrations of Fe, Mn, Cu and Zn in leaves were higher than those in stems. The second investigation is a survey on the levels of As and other heavy metals in vegetation in the vicinity of Myoungbong mine tailings. The results demonstrated that As, Pb and Cu concentrations and bioaccumulation factors (BCF) in seedlings of the fern(A splenium achilleifolium) were the highest, whereas Marsh horsetail(Equisetum polustre) accumulated the highest levels of Zn. Concentrations of As, Pb, Zn and Cu in vegetable-cress (Lepidium sativum) and the edible herb-aromatic madder (Elasholtzia splendens) were higher than food safety limits. Therefore, a risk assessment of As and other heavy metals in vegetables and herbs on local human health should be conducted in the future.展开更多
In the present study, arsenate(As(V)) and phosphate(P(V)) interactions were investigated in growth, uptake and RNA content in yeast(Saccharomyces cerevisiae). Yeast grew slowly with As(V) concentrations in...In the present study, arsenate(As(V)) and phosphate(P(V)) interactions were investigated in growth, uptake and RNA content in yeast(Saccharomyces cerevisiae). Yeast grew slowly with As(V) concentrations increasing in the medium. However, the maximal population density was almost the same among different As(V) treatments. It was in the late log phase that yeast growth was aug- mented by low As(V), which was maybe due to the fact that methionine metabolism was stressed by vitamin B6 deprivation, so As(V) treatments did not affect maximal population density. However, with P (V) concentrations increasing, the maximal population density increased. Therefore, the maximal population density was determined by P (V) concentrations in the medium but not by As (V) concentrations in the medium. Ycflp(a tonoplast transpor) transports As(GS)3 into the vacuole, but arsenic(As) remaining in the thalli was 1.27% with As(V) exposure for 60 h, from which it can be speculated that the percentage of As transported into vacuole should be lower than 1.27%. However, the percentage of As pumped out of cell was 71.49% with As (V) exposure for 68 h. Although two pathways (extrusion and sequestration) were involved in As detoxification in yeast, the extrusion pathway played a major role in As detoxification. RNA content was the highest in the early-log phase and was reduced by As(V).展开更多
水环境中的微塑料和微生物抗生素抗性基因复合污染已经发展成为全球性的重大环境问题,给人类健康和生态环境带来新的挑战.海水中的微塑料残留日益增加,但是不同种类微塑料对海水抗生素抗性基因的干扰和影响还不是很清楚.选择了聚乙烯(PE...水环境中的微塑料和微生物抗生素抗性基因复合污染已经发展成为全球性的重大环境问题,给人类健康和生态环境带来新的挑战.海水中的微塑料残留日益增加,但是不同种类微塑料对海水抗生素抗性基因的干扰和影响还不是很清楚.选择了聚乙烯(PE)、聚氯乙烯(PVC)和具有一定水溶性的聚乙烯醇(PVA)这3种乙烯基微塑料,采集海水并添加微塑料进行了曝气培养实验(49 d),利用高通量定量PCR技术,研究微塑料对海水抗生素抗性基因的影响.结果表明,空白对照海水、添加PE海水、添加PVC海水和添加PVA海水抗生素抗性基因的种类分别为20、35、42和64种,微塑料使得海水中的抗生素抗性基因种类显著增多;在丰度水平上,空白对照海水、添加PE海水、添加PVC海水和添加PVA海水抗生素抗性基因的丰度分别为4.01×10^(6)、2.75×10^(7)、4.54×10^(7)和1.05×10^(8)copies·L^(-1),微塑料显著增加了海水中抗生素抗性基因的丰度.因此,相较于空白对照海水,微塑料显著增加了海水抗生素抗性基因多样性和丰度水平;OLS回归分析显示,抗生素抗性基因与16S r RNA基因和可移动遗传元件有着显著正相关关系,说明微生物的丰度和基因水平转移机制能够影响海水抗生素抗性基因的分布、存续和演变.展开更多
基金the National Natural Science Foundation of China (No.40321101)the Ministry of Science and Technology of China (No.2005CB121105) the Knowledge Innovation Program of the Chinese Academy of Sciences(Nos.KZCX1-SW-19 and KZCX2-YW-408).
文摘An experiment with seven N, P, K-fertilizer treatments, i.e., control (no fertilizer), NP, NK, PK, NPK, NP2K, and NPK2 where P2 and K2 indicate double amounts of P and K fertilizers respectively, was conducted to examine the effect of long-term continuous application of chemical fertilizers on microbial biomass and functional diversity of a black soil (Udoll in the USDA Soil Taxonomy) in Northeast China. The soil microbial biomass C ranged between 94 and 145 mg kg-1, with the NK treatment showing a lower biomass; the functional diversity of soil microbial community ranged from 4.13 to 4.25, with an increasing tendency from control to double-fertilizer treatments, and to triple-fertilizer treatments. The soil microbial biomass, and the microbial functional diversity and evenness did not show any significant differences among the different fertilizer treatments including control, suggesting that the long-term application of chemical fertilization would not result in significant changes in the microbial characteristics of the black soil.
文摘Heavy metal contamination of soils through anthropogenic activities is a widespread and serious problem confronting scientists and regulators throughout the world. In this study we investigated the distribution, chemical species and availability of lead, zinc, cadmium and copper in nine surface(0 to 20 cm) soils from near an abandoned lead/zinc mine tailings located in Shaoxing, Zhejiang, China. Total heavy metal contents ranged from 5271 to 16369 mg/kg for Pb, 387 to 1221 mg/kg for Zn, 3.0 to 9.3 mg/kg for Cd and 65 to 206 mg/kg for Cu. In general, all heavy metals exceeded China National Standards for Soil Environmental Quality of Heavy Metals by a factor of 3-65 times. Comparison of the heavy metal concentrations(Pb, Zn, Cd and Cu) with clay content revealed a strongly significant relationship while significant relationship( P 〈 0.001 ) was also obtained between Cd + Zn and Pb + Cu. Solid phase speciation of the soils using Tessier procedure showed that the heavy metals were distributed in the order: residual 〉〉 organically complexed-Fe-Mn oxides occluded 〉 carbonate bound 〉 exchangeable 〉 water soluble. In the organic matter fraction, the ratio of Pb(29.1% ) to its total concentration in the soils was higher than those of Zn(4.70% ), Cd(3.16% ) and Cu(9.50% ). The percentages of the water soluble and the exchangeable fractions of Pb(1.80% ) and Cd(2.74% ) were markedly greater than those of Zn(0.10% ) and Cu(0.15% ), suggesting that Pb and Cd are relatively more mobile and hence more toxic in the contaminated soils. Strongly significant relationships between H20-Pb, H20-Zn and H20-Cu, strong positive correlations between H20-Pb, H20-Zn, H20-Cu and organic matter in soil were found. The content of H20-Pb, H20-Zn, H20-Cu was negatively correlated with pH values. The similar negative relationships between pH values and exchangeable heavy metals were also recorded. It is suggested that increasing soil pH or liming the soil could decrease bioavailability of heavy metals in the soil.
基金The National Natural Science Foundation of China as an Outstanding Youth Fund grant (No. 20225722) the National NaturalScience Foundation for the Joint China-Russia Project (No. 20611120015)
文摘Ecological effects of crude oil residues on weed rhizospheres are still vague. The quantitative and diversity changes and metabolic responses of soil-bacterial communities in common dandelion (Taraxacum officinale), jerusalem artichoke (Silphiurn perfoliatum L.) and evening primrose (A colypha australis L.) rhizospheric soils were thus examined using the method of carbon source utilization. The results indicated that there were various toxic effects of crude oil residues on the growth and reproduction of soil bacteria, but the weed rhizospheres could mitigate the toxic effects. Total heterotrophic counting colony-forming units (CFUs) in the rhizospheric soils were significantly higher than those in the non-rhizospheric soils. The culturable soil-bacterial CFUs in the jerusalem artichoke (S. perfoliatum) rhizosphere polluted with 0.50 kg/pot of crude oil residues were almost twice as much as those with 0.25 kg/pot and without the addition of crude oil residues. The addition of crude oil residues increased the difference in substrate evenness, substrate richness, and substrate diversity between non-rhizospheric and rhizospheric soils of T. officinale and A. australis, but there was no significant (p〉0.05) difference in the Shannon's diversity index between non-rhizospheric and rhizospheric soils of S. perfoliatum. The rhizospheric response of weed species to crude oil residues suggested that S. perfoliatum may be a potential weed species for the effective plant-microorganism bioremediation of contaminated soils by crude oil residues.
基金the National Natural Science Foundation of China (No.40071053) Henan Provincial Talents Innovation Foundation, China (No.0521001700).
文摘A study was conducted to determine the relationships between agronomic soil test P and environmental soil test P in three soils predominately distributing in three typical agricultural production areas of China. Soil P was analyzed using Bray-1 (BP), Olsen (OP), and Mehlich-3 (MP) methods as agronomic tests, and using Fe-oxide impregnated filter paper (FeP), anion-exchange resin membrane (RP), and water (WP) as environmental tests. There were linear relationships between soil P extractable with all the tests evaluated. The regression coeffcients, R2, ranged from 0.8164 to 0.9409 between each two of the agronomic soil test P, and ranged from 0.4702 to 0.8990 between each two of the environmental soil test P, when the three soils were considered separately. When soil test P was analyzed across all the three soils, the highest regression R2 was found between OP and MP (0.7940) amongst agronomic soil test P, and between FeP and RP amongst environmental soil test P (0.8842). While all of the three agronomic soil test P was linearly related to each of the environmental soil test P across the three soils, strongest relationships were found between OP and environmental soil test P. Agronomic OP may be adopted as an analytical tool for environmental prediction of soil P.
基金TheNationalN aturalScienceFoundationofChina (N o.4022500220477055)theM inistryofScienceandTechnology(No.2002CB410808)andtheUN U & GISTJointProgram m eonScienceandTechnologyforSustainability(IERC)
文摘This research includes two investigations. The first one is a market basket survey of the levels of arsenic (As) and trace elements in bracken fern (Pteridium aquilinum) originated from three countries: South Korea, China and North Korea. The results showed that the mean As concentrations in stems of samples were significantly higher than those in leaves. As concentrations in all samples did not exceed food safety limits for vegetables. Generally, concentrations of Fe, Mn, Cu and Zn in leaves were higher than those in stems. The second investigation is a survey on the levels of As and other heavy metals in vegetation in the vicinity of Myoungbong mine tailings. The results demonstrated that As, Pb and Cu concentrations and bioaccumulation factors (BCF) in seedlings of the fern(A splenium achilleifolium) were the highest, whereas Marsh horsetail(Equisetum polustre) accumulated the highest levels of Zn. Concentrations of As, Pb, Zn and Cu in vegetable-cress (Lepidium sativum) and the edible herb-aromatic madder (Elasholtzia splendens) were higher than food safety limits. Therefore, a risk assessment of As and other heavy metals in vegetables and herbs on local human health should be conducted in the future.
基金The Natural Science Foundation of China (No. 40225002) the Ministry of Science and Technology of China (No. 2002CB410808) and the Chinese Academy of Sciences (Hundred Talent Program)
文摘In the present study, arsenate(As(V)) and phosphate(P(V)) interactions were investigated in growth, uptake and RNA content in yeast(Saccharomyces cerevisiae). Yeast grew slowly with As(V) concentrations increasing in the medium. However, the maximal population density was almost the same among different As(V) treatments. It was in the late log phase that yeast growth was aug- mented by low As(V), which was maybe due to the fact that methionine metabolism was stressed by vitamin B6 deprivation, so As(V) treatments did not affect maximal population density. However, with P (V) concentrations increasing, the maximal population density increased. Therefore, the maximal population density was determined by P (V) concentrations in the medium but not by As (V) concentrations in the medium. Ycflp(a tonoplast transpor) transports As(GS)3 into the vacuole, but arsenic(As) remaining in the thalli was 1.27% with As(V) exposure for 60 h, from which it can be speculated that the percentage of As transported into vacuole should be lower than 1.27%. However, the percentage of As pumped out of cell was 71.49% with As (V) exposure for 68 h. Although two pathways (extrusion and sequestration) were involved in As detoxification in yeast, the extrusion pathway played a major role in As detoxification. RNA content was the highest in the early-log phase and was reduced by As(V).
文摘水环境中的微塑料和微生物抗生素抗性基因复合污染已经发展成为全球性的重大环境问题,给人类健康和生态环境带来新的挑战.海水中的微塑料残留日益增加,但是不同种类微塑料对海水抗生素抗性基因的干扰和影响还不是很清楚.选择了聚乙烯(PE)、聚氯乙烯(PVC)和具有一定水溶性的聚乙烯醇(PVA)这3种乙烯基微塑料,采集海水并添加微塑料进行了曝气培养实验(49 d),利用高通量定量PCR技术,研究微塑料对海水抗生素抗性基因的影响.结果表明,空白对照海水、添加PE海水、添加PVC海水和添加PVA海水抗生素抗性基因的种类分别为20、35、42和64种,微塑料使得海水中的抗生素抗性基因种类显著增多;在丰度水平上,空白对照海水、添加PE海水、添加PVC海水和添加PVA海水抗生素抗性基因的丰度分别为4.01×10^(6)、2.75×10^(7)、4.54×10^(7)和1.05×10^(8)copies·L^(-1),微塑料显著增加了海水中抗生素抗性基因的丰度.因此,相较于空白对照海水,微塑料显著增加了海水抗生素抗性基因多样性和丰度水平;OLS回归分析显示,抗生素抗性基因与16S r RNA基因和可移动遗传元件有着显著正相关关系,说明微生物的丰度和基因水平转移机制能够影响海水抗生素抗性基因的分布、存续和演变.