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Effect of biosurfactant on the sorption of phenanthrene onto original and H_2O_2-treated soils

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Journal of environmental sciences 2009年第10期21卷 1378-1385页

作者： PEI Xiaohong, ZHAN Xinhua, zhou lixiang college of resources and environmental sciences, nanjing agricultural university, nanjing 210095, china. [a]college of resources and environmental sciences Nanjing Agricultural University Nanjing 210095 China. E-mail: ***@***

The objective of this study was to examine the effect of biosurfactant on the sorption of phenanthrene （PHE） onto the original or HzO2-treated black loamy soil （typic isohumisols） and red sandy soil （typic ferralisols）. The sorption isotherms were performed with the original and ＂soft＂ carbon-removed soils in the presence and absence of biosurfactant （200 mg/L）. The sorption and degradation of biosurfactant were investigated. The result showed that organic matter played an important role in PHE sorption onto the black loamy and red sandy soils, and the PHE sorption isotherms on the ＂soft＂ carbon-removed soils exhibited more nonlinearity than those on the original soils. The values of partition coefficient （Kd） on the original black loamy soil with or without 200 mg/L biosurfactant were 181.6 and 494.5 mL/g, respectively. Correspondingly, in the red sandy soil, Kd was 246.4 and 212.8 mL/g in the presence or absence of biosurfactant, respectively. The changes of Kd suggested that biosurfactant inhibited PHE sorption onto the black loamy soil, but facilitated PHE sorption onto the red sandy soil. The nonlinearity of PHE sorption isotherm was decreased in the presence of biosurfactant. Site specific sorption might occur during PHE sorption onto both the original and the ＂soft＂ carbon-removed soils in the presence of biosurfactant. It was noted that biosurfactant could also be sorbed onto soils. The maximal sorption capacity of the red sandy soil for biosurfactant was （76.9 ± 0.007） μg/g, which was 1.31 times that of black loamy soil. Biosurfactant was degraded quickly in the two selected soils, and 92% of biosurfactant were mineralized throughout the incubation experiment for 7 d. It implied that biosurfactant should be added frequently when the remediation of polycyclic aromatic hydrocarbon （PAH）-contaminated soils was conducted through PAH desorption approach facilitated by biosurfactant.

关键词： biosurfactant phenanthrene sorption "soft" carbon soil

Conditioning treatments mitigate the levels of fecal pollution indicators in soil during land-application of sewage sludge

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Science china.Technological sciences 2024年第10期67卷 3091-3102页

作者： WANG YuHang li Hua FANG WenHao WANG Ru WANG XinXin ZHENG GuanYu zhou lixiang Department of environmental Engineering College of Resources and Environmental SciencesNanjing Agricultural University college of Materials and Chemical Engineering Pingxiang University Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization

Sewage sludge is a major source of fecal pathogens in the environment, and its application to land can result in a significant release of these pathogens into the soil. While conditioning treatments are crucial for improving the dewatering process of sludge, their impact on the presence and behavior of fecal pathogens in soil remains unclear. This study aims to assess four extraction methods for recovering fecal pollution indicators from soil amended with unconditioned and conditioned sludge. The indicators include Escherichia coli(EC), human-specific HF183 Bacteroides(HF183), human adenovirus(HAdV), human BK polyomavirus(BKPyV), human JC polyomavirus(JCPyV), and cross-assembly phage(crAssphage). This study also examines how soil moisture content affects the decay of these fecal pollution indicators in soil amended with raw sludge and investigates the influence of conditioning treatments with cationic polyacrylamide(PAM), Fenton's reagents, Fe[Ⅲ]/CaO on their persistence in soil. The results indicated that the direct extraction method was the most effective and unbiased for recovering fecal pollution indicators from sludge-amended soil compared with the three elution-concentration methods. All fecal pollution indicators, except HAdV, remained stable under dry soil conditions, while high soil moisture content(48.39%-53.14%) slowed the decay rates of these indicators. During the application of sludge to soil, effective control of fecal pollution indicators was observed, with JCPyVand HAdV becoming undetectable within a short period. The log reduction values of HF183, BKPyV, and crAssphage ranged from 0.1 to 2.8 logs after 30 d of cultivation. The application of conditioned sludge, especially Fenton's reagent-conditioned sludge, resulted in a reduction in human fecal contamination in the receiving soil. Therefore, implementing appropriate conditioning methods, such as using Fenton's reagent, can effectively mitigate the health risks associated with fecal pathogens.

关键词： fecal pollution indicators sewage sludge conditioning treatment land application soil

Acetylacetone effectively controlled the secondary metabolites of Microcystis aeruginosa under simulated sunlight irradiation

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Journal of environmental sciences 2024年第1期135卷 285-295页

作者： Xiaomeng Wang Yixin Luo Shujuan Zhang lixiang zhou Department of environmental Engineering College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095China The State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentNanjing UniversityNanjing 210023China

Inactivation of cyanobacterial cells and simultaneous control of secondary metabolites is of significant necessity for the treatment of cyanobacteria-laden ***(AcAc)has been reported a specific algicide to inactivate Microcystis aeruginosa(***)and an effective light activator to degrade *** study systematically investigated the photodegradation ability of AcAc under xenon(Xe)irradiation on the secondary metabolites of ***,mainly algal organic matter(AOM),especially toxic microcystin-LR(MC-LR).Results showed that AcAc outperformed H_(2)O_(2)in destructing the protein-like substances,humic acid-like matters,aromatic proteins and fulvic-like substances of *** MC-LR(250μg/L),0.05 mmol/L AcAc attained the same degradation efficiency(87.0%)as 0.1mmol/L H_(2)O_(2).The degradation mechanism of Xe/AcAc might involve photo-induced energy/electron transfer and formation of carbon center *** conditions(pH>9.0)were detrimental to the photoactivity of AcAc,corresponding to the observed degradation rate constant(k_(1)value)of MC-LR drastically decreasing to 0.0013 min^(-1)as solution pH exceeded *** PO_(4)^(3-)and HCO_(3)^(-)ions had obvious inhibition effects,whereas NO_(3)^(-)slightly improved k_(1)value from 0.0277 min^(-1)to 0.0321 min^(-1).The presence of AOM did not significantly inhibit MC-LR degradation in Xe/AcAc *** addition,the biological toxicity of MC-LR was greatly reduced after *** results demonstrated that AcAc was an alternative algicidal agent to effectively inactivate algal cells and simultaneously control the secondary metabolites after cell ***,the concentration and irradiation conditions should be further optimized in practical application.

关键词： Microcystis aeruginosa Photodegradation Acetylacetone Secondary metabolites Microcystin

Interactive effect of dissolved organic matter and phenanthrene on soil enzymatic activities

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Journal of environmental sciences 2010年第4期22卷 607-614页

作者： Xinhua Zhan,Wenzhu Wu,lixiang zhou,Jianru liang,Tinghui Jiang college of resources and environmental sciences,nanjing agricultural university,nanjing 210095,china.Greenstar Plant Products Inc.,9430 198 St,Langley,BC,Canada V1M3C8. [a] college of resources environmental sciences Nanjing Agricultural University Nanjing 210095 China

The investigation of dissolved organic matter （DOM） on urease, catalase and polyphenol oxidase activity in a phenanthrene （Phe）- contaminated soil was conducted under laboratory incubation conditions. Values of soil enzymatic activity depended mainly on incubation time. In the initial 16 days, urease activity increased, and was followed by a decrease. In the initial 8 days, catalase activity decreased and then increased. Variation of polyphenol oxidase activity was just the reverse of catalase activity. After 30 days of incubation, no pronounced difference among treatments with Phe, Phe and DOM, and control were detected in urease, catalase and polyphenol oxidase activity. Phe might inhibit urease and catalase, and stimulate polyphenol oxidase. DOM could improve inhibition of Phe in soil urease and catalase activity during the initial period of applying DOM. Nevertheless, DOM had no significant effect on polyphenol oxidase activity in the Phe contaminated soil. There was a negative correlation between catalase and polyphenol oxidase （r = -0.761＊＊＊）, and catalase and urease （r = -0.554＊＊）. Additionally, a positive correlation between polyphenol oxidase and urease was also detected （r = 0.701＊＊＊）. It is implied that the formed DOM after application of organic wastes into soils may counteract the inhibition of polycyclic aromatic hydrocarbons in soil enzyme activities.

关键词： polycyclic aromatic hydrocarbons dissolved organic matter phenanthrene soil enzymes

Effects of a Biosurfactant and a Synthetic Surfactant on Phenanthrene Degradation by a Sphingomonas Strain

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Pedosphere 2010年第6期20卷 771-779页

作者： PEI Xiao-Hong ZHAN Xin-Hua WANG Shi-Mei liN Yu-Suo zhou li-Xiang college of resources and environmental sciences Nanjing Agricultural University Nanjing 210095 (China) nanjing Institute of environmental sciences Ministry of Environmental Protection of China Nanjing 210042 (China)

A novel phenanthrene (PHE)-degrading strain named as Sphingomonas ***2B was isolated and identified from a farmland *** of a synthetic surfactant (Tween-80) and a rhamnolipid biosurfactant on PHE degradation by Sphin- gomonas ***2B were investigated at different concentrations of the *** results showed that Sphingomonas ***2B was able to mineralize up to 83.6% of PHE within 10 days without addition of *** addition of Tween-80 to the reaction medium inhibited greatly PHE biodegradation,with only 33.5% of PHE ***,the biosurfactant facilitated PHE biodegradation,with up to 99.5% of PHE *** preferential utilization of PHE as a carbon source and the enhanced solubility of PHE by the biosurfactant were likely responsible for the higher biodegra- dation efficiency of PHE in the presence of the ***,it could be concluded that the application of the biosurfactant to PHE-contaminated soils was perhaps a feasible way to facilitate the PHE biodegradation.

关键词： biodegradation contaminated soils rhamnolipid solubility Tween-80

Can Cadmium Uptake by Chinese Cabbage be Reduced After Growing Cd-Accumulating Rapeseed?

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Pedosphere 2010年第1期20卷 90-95页

作者： SU De-Chun , JIAO Wei-Ping, zhou Man and CHEN Xia college of resources and environmental sciences, china.agricultural university, Beijing 100193 (china. [a] college of resources and environmental sciences China Agricultural University Beijing 100193 (China)

Rapeseed （Brassica campestris L.）, a Cd-accumulating crop, is effective in reducing plant-available Cd from soil. A pot experiment was conducted to test the hypothesis that the Cd uptake by Chinese cabbage （Brassica pekinensis Rupr.） grown in rotation with rapeseed would be reduced due to the efficient removal of bioavailable Cd from soil solution by the rapeseed crops. The Cd removal by shoot for the rapeseed cultivar Zhucang Huazi ranged from 0.24% to 0.99% in natural Cd-contaminated soil （soil A） and from 0.63% to 1.23% in artificial Cd-contaminated soil （soil B） during the growth period of 4 7 weeks; whereas that for the rapeseed cultivar Chuanyou Ⅱ-93 ranged from 0.25% to 0.66% and from 0.38% to 1.02%, respectively. Chinese cabbage grown in the pots with soil A for five weeks after harvesting rapeseed exhibited a significantly lower Cd concentration compared to that grown in the control pots （uncropped with rapeseed）. However, the rotation of rapeseed did not lower the Cd concentration of Chinese cabbage on soil B. Although an increase of Cd uptake was observed in the rapeseed cultivars with growth time, and the decrease of soil NH4OAc-extractable Cd was found only in the natural rather than artificial Cd-contaminated soil.

关键词： Cd-contaminated soil crop rotation heavy metal phytoremediation plant-available Cd

New Insights into the Nitrogen Form Effect on Photosynthesis and Photorespiration

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Pedosphere 2007年第5期17卷 601-610页

作者： GUO Shi-Wei zhou Yi GAO Ying-Xu li Yong SHEN Qi-Rong college of resources and environmental sciences Nanjing Agricultural University Nanjing 210095 （China）

Under high light conditions, ammonium nutrition has a negative effect on plant growth. This suggests that the adverse effects of ammonium nutrition on plant growth may be related to carbon gain, photosynthesis, and photorespiration. However, there is no consistent evidence of a specific mechanism that could explain the plant growth reduction under ammonium supply. It is generally accepted that during the light reaction, a surplus of nicotinamide adenine dinucleotide hydrogen phosphate （NADPH） is produced, which is not completely used during the assimilation of CO2, Nitrate reduc- tion in the leaf represents an additional sink for NADPH that is not available to ammonium-grown plants. Nitrate and ammonium nutrition may use different pathways for NADPH consumption, which leads to differences in photosynthesis and photorespiration. The morphological （i.e., cell size, mesophyll thickness, and chloroplast volume） and enzymic （i.e., ribulose-1,5-bisphosphate carboxylase/oxygenase （Rubisco）, phosphoenolpyruvate carboxylase （PEPCase）, and glutamine synthetase/glutamate synthetase （GS/GOGAT）） differences that develop when plants are treated with either nitrate or ammonium nitrogen forms are related to photosynthesis and photorespiration. The differences in photorespiration rate for plants treated with nitrate or ammonium are related to the conversion of citrate to 2-oxoglutarate （2-OG） and photorespiratory CO2 refixation.

关键词： ammonium nitrate nitrogen form photorespiration photosynthesis

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我国中部沿海陆域与海岛土壤属性差异的研究

土壤学报 2003年第3期40卷 407-413页

作者：周静陈巍方明陈邦本中国科学院南京土壤研究所南京210008 南京农业大学资源与环境学院南京210095

以我国浙江、江苏、山东三省沿海陆域和海岛酸性母岩风化物上发育的 8个土壤剖面为对象 ,以海岛和陆域同纬度方向比较研究海陆不同生境下发育的土壤基本属性 ,阐明陆域和海岛土壤在同纬度同类型母质上发育程度的差异。结果表明 :海岛土... 详细信息

以我国浙江、江苏、山东三省沿海陆域和海岛酸性母岩风化物上发育的 8个土壤剖面为对象 ,以海岛和陆域同纬度方向比较研究海陆不同生境下发育的土壤基本属性 ,阐明陆域和海岛土壤在同纬度同类型母质上发育程度的差异。结果表明 :海岛土壤pH值、盐基饱和度、粉粘比、粘粒的硅铝率和硅铁铝率比同纬度相邻陆域土壤高 ,土体红化率、粘化率比相邻陆域土壤低 ;海岛土壤区别于陆域土壤的最明显特征是其具有复盐基作用 ;成土过程的强度均是在海岛低于同纬度相邻的陆域土壤。

关键词：陆域海岛土壤属性复盐基作用分类

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土壤中溶解性有机质分组组分的结构特征研究

土壤学报 2004年第5期41卷 721-727页

作者：代静玉秦淑平周江敏南京农业大学资源与环境学院南京210095

以Leenheer的分组方法为基础 ,用XAD 8树脂将黄泥土中水溶性有机质 (DOM)按极性和电荷特性分为结构较为均一的不同组分 ,并采用元素分析、1 H NMR以及CP/MAS1 3 C NMR研究各组分的性质。初步认为 :三种不同利用方式下 (桑园、水田、水... 详细信息

以Leenheer的分组方法为基础 ,用XAD 8树脂将黄泥土中水溶性有机质 (DOM)按极性和电荷特性分为结构较为均一的不同组分 ,并采用元素分析、1 H NMR以及CP/MAS1 3 C NMR研究各组分的性质。初步认为 :三种不同利用方式下 (桑园、水田、水杉 )黄泥土中的DOM组成中疏水碱性组分 (HOB)含量很少 ,疏水中性组分 (HON)相对含量为 7%～ 1 5 %,亲水性组分 (HIM)是土壤DOM中最大组成部分 ,约占 35 %。元素分析、1 H NMR以及1 3 C NMR分析结果表明 :DOM各组分结构特征差异显著。HON以含有大量的长链烷烃为主要结构特征 ,并含有较多氨基酸、多肽类物质 ;疏水酸性组分 (HOA)的结构特征相似于土壤FA ,含有大量羧基 ,但与FA相比芳香族物质减少 ,碳水化合物增多 ;酸不溶组分 (AIM)以多酚类、腐殖质结合的碳水化合物为主要组成物质 ;HIM中则含有大量碳水化合物。

关键词：土壤溶解性有机质分组组分结构特征