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Frontiers of Environmental Science & Engineering 2015年第3期9卷 475-481页

作者： Yong YU laosheng wu Department of Environmental Sciences University of Califomia Riverside CA 92521 USA

Endocrine disrupting compounds （EDCs）, pharmaceuticals and personal care products （PPCPs） have attracted much attention due to widespread contamination in aquatic environment. In this study, we determined 13 EDCs and PPCPs in fish blood, bile and muscle by using gas chromatography-mass spectrometry （GC-MS）. The limits of quantitation （LOQ） were in the ranges of 0.23-2.54, 0.22-2.36ng·mL^-1, and 0.24-2.57 ng· g^-1 dry weight （dw） for fish blood, bile and muscle, respectively. Recoveries of target compounds spiked into sample matrices and passed through the entire analytical procedure ranged from 65% to 95%, from 60% to 92% and from 62% to 91% for blood, bile and muscle, respectively. The methods were applied to the analysis of fish from a lake in California. Target compounds were relatively low in bile, and only bisphenol A （BPA） and diclofenac were measurable near the LOQ. Seven of 13 compounds were detected in blood, with total concentrations up to 39 ng· g^-1. Only BPA was frequently found in muscle, with mean concentration of 7.26 ng· g^-1 dw. The estimated daily intake of BPA through fish consumption for U.S. resident was significantly lower than the tolerable daily intake recommended by the European Food Safety Authority. This study showed that the exposure to the bisphenol A from fish diet is unlikely to pose a health risk.

关键词： endocrine disrupting compounds (EDCs) pharmaceuticals and personal care products (PPCPs) fish bisphenol A (BPA) risk assessment

Numerical modeling of double-ring infiltrometers for determining saturated hydraulic conductivity of heterogeneous and anisotropic soils

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Pedosphere 2024年第6期34卷 1111-1122页

作者： Xiaoting XIE Hongxiang ZHOU laosheng wu Jun MAN Institute of Soil Science Chinese Academy of Sciences Department of Geographic Science Faculty of Arts and Sciences Beijing Normal University at Zhuhai College of Metrology and Measurement Engineering China Jiliang University Department of Environmental Sciences University of California

Philip’s two-term infiltration equation has been widely used to infer soil saturated hydraulic conductivity (Ks),the accuracy of which is usually influenced by the size of infiltration rings and soil *** studies have primarily focused on exploring the ring-size dependence of Ks estimations under specific soil conditions (e.g.,soil isotropy and/or uniform initial water content).This study aimed to provide a comprehensive analysis by systematically considering eight heterogeneous and anisotropic soils with nonuniform initial water ***,we examined the validity of Philip’s infiltration equation as well as the recently proposed two forms (i.e.,infiltration and time forms) of Parlange’s infiltration equation both theoretically and in practical applications of double-ring *** the time form of Parlange’s equation was applied to infer Ks using double-ring infiltrometer measurements with different combinations of six inner ring diameters (10,20,40,80,120,and 200 cm) and three buffer index (defined as the ratio of the difference between inner and outer ring diameters to the outer ring diameter) values (0.20,0.33,and 0.50).For each infiltrometer set,20 stochastic Ks fields were randomly generated by adopting five standard deviation values (0.1,0.3,0.5,0.7,and 0.9).Furthermore,we investigated the effects of five horizontal correlation lengths (30,60,150,300,and 600 cm) on Ks *** results demonstrated that Parlange’s equation,compared to Philip’s equation,was more universal in describing the cumulative infiltration relationship for the test *** combination of inner ring diameter and buffer index of 40 cm and 0.2,respectively,which satisfied most of the practical requirements for determining Ks in the Soil Water Infiltration Global (SWIG) database was *** the horizontal correlation length exceeded a threshold (i.e.,150 cm in our study),the inner ring diameter was required to increase to 80 *** findings co

关键词： heterogeneous soil infiltration equation numerical modeling soil anisotropy soil hydraulic conductivity

Organic carbon stratification and size distribution of three typical paddy soils from Taihu Lake region,China

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Journal of Environmental Sciences 2008年第4期20卷 456-463页

作者： PAN Genxing wu laosheng LI Lianqing ZHANG Xuhui GONG Wei WOOD Yvonne Institute of Resource Ecosystem and Environment of Agriculture Nanjing Agricultural University Nanjing 210095 China Department of Environmental Sciences University of California Riverside CA 92521 USA

Developing realistic soil carbon （C） sequestration strategies for China＇s sustainable agriculture relies on accurate estimates of the amount, retention and turnover rates of C stored in paddy soils. Available C estimates to date are predominantly for the tilled and flood-irrigated surface topsoil （ca. 30 cm）. Such estimates cannot be used to extrapolate to soil depths of 100 cm since soil organic carbon （SOC） generally shows a sharp decrease with depth. In this research, composite soil samples were collected at several depths to 100 cm from three representative paddy soils in the Taihu Lake region, China. Soil organic carbon distribution in the profiles and in aggregate-size fractions was determined. Results showed that while SOC decreased exponentially with depth to 100 cm, a substantial proportion of the total SOC （30%-40%） is stored below the 30 cm depth. In the carbon-enriched paddy topsoils, SOC was found to accumulate preferentially in the 2-0.25 and 0.25-0.02 mm aggregate size fractions. δ^13C analysis of the coarse micro-aggregate fraction showed that the high degree of C stratification in the paddy topsoil was in agreement with the occurrence of lighter δ^1313C in the upper 30 cm depth. These results suggest that SOC stratification within profiles varies with different pedogenetical types of paddy soils with regards to clay and iron oxyhydrates distributions. Sand-sized fractions of aggregates in paddy soil systems may play a very important role in carbon sequestration and turnover, dissimilar to other studied agricultural systems.

关键词： profile stratification organic carbon paddy soils size fractions soil aggregates carbon storage

Impacts of soil organic matter, pH and exogenous copper on sorption behavior of norfloxacin in three soils

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Journal of Environmental Sciences 2009年第5期21卷 632-640页

作者： ZHANG Jie LI Zhaojun GE Gaofei SUN Wanchun LIANG Yongchao wu laosheng College of Natural Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 China Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 China Key Laboratory of Oasis Eco-Agriculture and College of Agriculture Shihezi University Shihezi 832003 China Department of Environmental Sciences University of California Riverside Riverside CA 92521 USA

Norfloxacin sorption and the factors （soil organic matter （SOM）, pH, and exogenous copper （Cu） influencing the sorption were investigated in a black soil （soil B）, a fluvo-aquic soil （soil F）, and a red soil （soil R）. With increasing norfloxacin concentrations, sorption amount of norfloxacin increased in both the bulk soils and their SOM-removed soils, but the sorption capacity of SOM-removed soils was higher than that of their corresponding bulk soils, indicating that the process of norfloxacin sorption in soil was influenced by the soil properties including SOM. The sorption data in all bulk soils and SOM-removed soils were fitted to Freundlich and Langmuir models. The correlation coefficients suggested that the experimental data fitted better to Freundlich equation than to Langmuir equation. Furthermore, the data from soil F and SOM-removed F could not be described by Langmuir equation. The norfloxacin sorption amount decreased in soil B and soil F, whereas it increased in soil R as solution pH increased. The maximum KD and Koc were achieved in soil R when the equilibrium solution pH was 6. The norfloxacin sorption was also influenced by the exogenous Cu^2＋, which depended on the soil types and Cu^2＋ concentrations. With increasing Cu^2＋ concentrations in solution, generally, sorption amount, KD and Koc for norfloxacin in soils increased and were up to a peak at 100 mg/L Cu^2＋, and then the sorption amount decreased regardless of norfloxacin levels.

关键词： copper norfloxacin pH soil organic matter sorption

Contrasting response of rice rhizosphere microbiomes to in situ cadmium-contaminated soil remediation

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Soil Ecology Letters 2024年第2期6卷 149-162页

作者： Zhongyi Cheng Qinyu Han Yan He Jiachun Shi laosheng wu Jianming Xu Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment Institute of Soil and Water Resources and Environmental ScienceCollege of Environmental and Resource SciencesZhejiang UniversityHangzhou310058China Key Laboratory of Environment Remediation and Ecological Health Ministry of EducationHangzhou310058China Department of Environmental Sciences University of CaliforniaRiversideCA92521USA

Changes in soil properties and microbial communities regulated rhizosphere protistan assemblages. • Bacterial community was more sensitive to soil amendments than protists and fungi. • Soil amendments trigger the role of specific protistan taxa Cercozoa on microbial interactions. Understanding the responses of different rhizosphere microbial lineages to soil amendments during in situ remediation of Cd-contaminated soil is of great importance in the assessment of the restoration and crop health. Here, we evaluated the effects of lime (LM), biochar (BC), pig manure (PM), and a commercial Mg-Ca-Si conditioner (CMC) on the rice rhizosphere soil physicochemical properties and community assembly of bacteria, fungi, and protists in a six-year consecutive application of soil amendments field trial. Our results indicated that among the four amendments, the BC and CMC had the best efficiency in increasing soil pH, which were 5.2% and 16.2%, respectively. Despite the differences in soil Cd concentrations is not noticeable, all the soil amendment treatments significantly decreased the proportion of available Cd in total Cd compared to the control. Soil amendments significantly altered the diversity of bacterial community, while they had no effect on fungal and protistan communities. Linear discriminant analysis effect size (LEfSe) showed that the bacteria was more sensitive to soil amendment-induced changes. For protists, treatments with LM and BC changed the groups of protistan consumers, while treatments with PM and CMC significantly increased the relative abundances of protistan phototrophs. Co-occurrence network analysis revealed that soil amendments increased microbial network complexity and triggered the role of protists, especially for the predatory protists Cercozoa, on microbial trophic interactions. Further variation partitioning analysis revealed that edaphic properties, bacterial and fungal communities compositions together explained the 77% of the total variation i

关键词： cadmium soil amendments soil protist community microbial interactions

三种南方典型水稻土长期试验下有机碳积累机制研究 Ⅱ．团聚体内有机碳的化学结合机制

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土壤学报 2009年第2期46卷 263-273页

作者：周萍宋国菡潘根兴李恋卿张旭辉 laosheng wu 南京农业大学农业资源与生态环境研究所南京210095 山东省济南市烟草专卖局济南250100 Department of Environmental of Sciences University of California Riverside CA 92521 USA

在对我国南方3种典型的水稻土有机碳团聚体分布研究的基础上,对用低能量超声波分散法分离得到的团聚体颗粒组进一步进行有机碳键合形态分析,考察不同键合态有机碳在不同粒径团聚体的分布,由此探讨这些水稻土中有机碳积累中物理作用基础... 详细信息

在对我国南方3种典型的水稻土有机碳团聚体分布研究的基础上,对用低能量超声波分散法分离得到的团聚体颗粒组进一步进行有机碳键合形态分析,考察不同键合态有机碳在不同粒径团聚体的分布,由此探讨这些水稻土中有机碳积累中物理作用基础上的化学机制。结果表明:钙键合态有机碳(Ca-SOC)多分布于2 000～200μm的粗团聚体颗粒组中,且在紫色水稻土中含量最高(达到9 g kg-1左右),而红壤性水稻土中最低(不到3 g kg-1);相反,铁铝键合态有机碳(Fe(Al)-SOC)趋向于在细团聚体颗粒组集中,是<2μm颗粒组中有机碳的优势组分,且以红壤性水稻土中最高(介于20～30 g kg-1之间),紫色水稻土中最低(仅为10 g kg-1左右),这与该团聚体颗粒组中铁铝氧化物的含量分布相吻合。统计分析表明,易氧化态碳(LOC)占有机碳(SOC)的比值与Ca-SOC占SOC的比值表现为正相关关系,而与Fe(Al)-SOC占SOC的比值表现为反相关关系。直径为2 000～200μm的粗团聚体中的Ca-SOC和Fe(Al)-SOC对长期不同耕作和施肥的响应最为敏感,良好的耕作施肥下水稻土有机碳的积累主要表现为Fe(Al)-SOC的增加。氧化铁铝的含量与SOC和LOC的含量之间存在一定的依变关系,说明这些土壤发生的无机组成分在有机碳的保护与稳定中发挥着重要作用,并且以红壤性水稻土粗团聚体中的氧化铁铝对有机碳的保护作用最强。由此看来,团聚体更新中物理保护的有机碳在细团聚体形成中进一步与氧化铁铝的键合可能是这些水稻土中有机碳稳定的重要机制。

关键词：水稻土有机碳团聚体农田管理长期试验土壤固碳化学保护

南方三种典型水稻土长期试验下有机碳积累机制研究 Ⅰ.团聚体物理保护作用

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土壤学报 2008年第6期45卷 1063-1071页

作者：周萍宋国菡潘根兴李恋卿张旭辉 laosheng wu 南京农业大学农业资源与生态环境研究所南京210095 山东省济南市烟草专卖局济南250100 Department of Environmental Sciences University of California Riverside CA 92521 USA

选取我国南方三种典型水稻土的长期试验田，采集长期不同处理下的未破坏土壤样品，采用低能量超声波分散法分离得到不同粒径的团聚体颗粒组，研究不同处理下这些团聚体颗粒组中的有机碳（Soil organic carbon，SOC）含量及其分配变化，... 详细信息

选取我国南方三种典型水稻土的长期试验田，采集长期不同处理下的未破坏土壤样品，采用低能量超声波分散法分离得到不同粒径的团聚体颗粒组，研究不同处理下这些团聚体颗粒组中的有机碳（Soil organic carbon，SOC）含量及其分配变化，探讨土壤有机碳积累与团聚体物理保护的关系。结果表明：供试三种水稻土团聚体颗粒组的组成以200—20μm和20～2μm粒径为主，分别占22％～43％和27％一44％，微团聚化作用较强。SOC含量以2000—200μm和〈2μm粒组中最高；而易氧化态碳（Labile organic carbon，LOC）主要富集于2000～200μm粗团聚体颗粒组中，其占SOC的比例（LOC／SOC）也是以该粒径中明显最高。直径为2000—200μm的粗团聚体颗粒组作为新增有机碳的主要载体，随不同耕作和施肥等长期处理的变化最为强烈，其中又以红壤性水稻土的SOC和LOC随不同施肥的变化最为强烈，说明其良好管理下的有机碳累积效应最为显著。统计分析表明，全土的有机碳积累量与2000～200μm粗团聚体的有机碳积累量之间的关系可用抛物线拟合（R2=0．95，n=8）。由此看来，长期试验下新固定的有机碳积累及其粗团聚体保护可能存在某种饱和机理。计算表明，供试水稻土的粗团聚体保护在长期试验期内还未达到其饱和限，本研究结果支持了我国学者对于近20年来南方水稻土特别是红壤丘陵区水稻土有机碳固定速率较高的认识。同时，红壤性水稻土的粗团聚体保护作用最强，仍然具有明显的固碳潜力，这也提示土壤中氧化铁对水稻土中有机碳的固定和化学稳定可能有重要贡献，水稻土固碳的团聚体保护作用与团聚体中有机碳的化学结合机制有关。

关键词：土壤固碳长期试验团聚体水稻土物理保护有机碳

孔隙尺度多孔介质流体流动与溶质运移高性能模拟

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水科学进展 2020年第3期31卷 422-432页

作者：周鸿翔郑延丰吴劳生陈铖曾令藻中国计量大学计量测试工程学院浙江杭州310018 Department of Mining and Minerals Engineering Virginia TechBlacksburgVA 24061USA 浙江大学环境与资源学院浙江杭州310058 浙江大学建筑工程学院浙江杭州310058 Department of Environmental Sciences University of CaliforniaRiversideCA 92521USA

深入探究孔隙尺度下的流体流动特性和溶质运移规律对石油开采、农田养分管理、地下水污染修复有着重要意义。以人工构建的多孔介质结构和同步辐射X射线显微CT扫描的土壤团聚体(分辨率3.7μm)为研究对象,在空间节点数多达64 000 000的情... 详细信息

深入探究孔隙尺度下的流体流动特性和溶质运移规律对石油开采、农田养分管理、地下水污染修复有着重要意义。以人工构建的多孔介质结构和同步辐射X射线显微CT扫描的土壤团聚体(分辨率3.7μm)为研究对象,在空间节点数多达64 000 000的情况下,基于格子Boltzmann模型和GPU并行技术计算得到多孔介质流体运动和溶质运移过程的关键参数,并据此探究多孔介质空间异质性对水力学特性的影响。通过对3组不同结构的多孔介质比较发现,结构复杂程度最高的土壤样品和不规则堆叠的圆球结构的渗透率在100 mD(即10^-13m^2)量级,远低于规则堆叠的圆球结构(>20 000 mD);土壤的迂曲度为1.40~1.60,明显高于规则堆叠的圆球结构。研究结果表明,渗透率大的样品具有较小的迂曲度,这与结构的空间异质性有较强的关系;土壤的渗透率和迂曲度呈现各向异性;在水力梯度一定的前提下,渗透率较大的样品,纵向弥散系数也较大;同时,结构的异质性也会影响溶质的穿透曲线。本研究提出的模拟方法可在土壤结构中进行高效的水流运动和溶质运移模拟,可用于土壤多孔介质在孔隙尺度下的水力学特性研究。

关键词：孔隙尺度格子Boltzmann法流体流动溶质运移

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离子界面反应对土壤饱和导水率的影响

离子界面反应对土壤饱和导水率的影响

优化法与贝叶斯估计法在非饱和水力参数反演中的比较

2019年中国土壤学会土壤环境专业委员会、土壤化学专业委员会联合学术研讨会

作者：刘新敏 Ting Yang Hang Li laosheng wu 土壤多尺度界面过程与调控重庆市重点实验室西南大学资源环境学院加州大学河滨分校环境科学系

土壤颗粒/水界面上离子-颗粒相互作用决定着土壤颗粒的表面性质,进而影响着土壤颗粒的凝聚与分散。土壤颗粒间相互作用强烈影响着土壤中水分运动。首先,本研究建立了考虑离子特异性效应的离子-土壤颗粒相互作用模型,进一步建立了钠吸附... 详细信息

土壤颗粒/水界面上离子-颗粒相互作用决定着土壤颗粒的表面性质,进而影响着土壤颗粒的凝聚与分散。土壤颗粒间相互作用强烈影响着土壤中水分运动。首先,本研究建立了考虑离子特异性效应的离子-土壤颗粒相互作用模型,进一步建立了钠吸附比(SAR)和电解质浓度(EC)与表面电位的理论关系。其次,推导出了混合电解质体系下颗粒间静电排斥力的理论计算方法,根据表面电位即可实现颗粒间中间电位的计算。第三,建立了颗粒间净

关键词：土壤饱和导水率土壤颗粒界面反应

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浙江大学学报（农业与生命科学版） 2016年第5期42卷 598-606页

作者：柯凤乔满俊曾令藻吴劳生浙江大学环境与资源学院土水资源与环境研究所杭州310058

非饱和土壤水分运动模型在农业生产和环境保护等领域中具有重要的指导意义。非饱和土壤水力参数的准确获取是利用模型进行可靠预测的前提。传统的参数反演研究大多基于优化方法,只能获取一组最优参数,不能量化其中的不确定性。最新发展... 详细信息

非饱和土壤水分运动模型在农业生产和环境保护等领域中具有重要的指导意义。非饱和土壤水力参数的准确获取是利用模型进行可靠预测的前提。传统的参数反演研究大多基于优化方法,只能获取一组最优参数,不能量化其中的不确定性。最新发展的一种基于贝叶斯参数估计理论的马尔科夫链蒙特卡罗算法(Markov Chain Monte Carlo,MCMC)—DREAM(ZS),可以有效进行参数反演,且准确量化不确定性。我们在获取水头观测值的基础上,利用MCMC和Levenberg-Marquardt(LM)非线性优化算法分别对非饱和土壤水力参数进行反演,通过数值模拟与一维沙柱入渗实验比较了2种方法对于分层异质的水力参数估计与水头预测的准确性。结果表明:1)LM优化方法使用广泛,求解速度较快,但受参数初始值影响较大,预测结果与观测值存在一定的偏差,同时由于只能给出一个单一的反演结果,无法量化结果的不确定性。2)与基于优化的反演方法相比,MCMC反演方法不仅能够更好地得出参数的单一估计值,同时预测结果与观测值也具有更好的一致性;更重要的是可以给出未知参数的后验分布,从而准确量化非饱和水力参数的不确定性,避免了基于单一参数反演结果进行预测的风险。但是相对于LM优化方法,MCMC计算量大大增加。

关键词：贝叶斯算法参数估计非饱和流不确定性