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Molecular signatures of soil-derived dissolved organic matter constrained by mineral weathering

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Fundamental Research 2023年第3期3卷 377-383页

作者： Ying-Hui Wang Peng Zhang Chen He Jian-Chun Yu Quan Shi randy a.dahlgren Robert G.M.Spencer Zhi-Bing Yang Jun-Jian Wang State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control School of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control School of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Shanghai Engineering Research Center of Hadal Science and Technology College of Marine SciencesShanghai Ocean UniversityShanghai 201306China Department of Land Air and Water ResourcesUniversity of California DavisDavis 95616United States Department of Earth Ocean and Atmospheric ScienceFlorida State UniversityTallahassee 32306United States

Dissolved organic matter(DOM)in soils drives biogeochemical cycling and soil functions in different directions depending on its molecular ***,there is a distinct paucity of information concerning how the molecular signatures of soil DOM vary with different degrees of weathering across wide geographic ***,we resolved the DOM molecular signatures from 22 diverse Chinese reference soils and linked them with soil organic matter and weathering-related mineralogical *** mixed-effects models revealed that the yields of DOM were determined by soil organic carbon content,whereas the molecular signature of DOM was primarily constrained by the weathering-related *** soil weathering index showed a positive effect on the lability and a negative effect on the aromaticity of ***,DOM in highly weathered acidic soils featured more amino sugars,carbohydrates,and aliphatics,as well as less O-rich polyphenols and condensed aromatics,thereby conferring a higher DOM biolability and lower DOM *** study highlights the dominance of the weathering-related dimension in constraining the molecular signatures and potential functions of DOM in soils across a wide geographic scale.

关键词： Soil organic matter Dissolved organic matter Chemical composition Molecular signature Mineral weathering

土地利用方式对流域氮输入输出关系的影响--以加州San Joaquin流域为例

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地理科学进展 2010年第9期29卷 1081-1086页

作者：韩震罗燏辀王中根 randy a.dahlgren 浙江大学生命科学学学院杭州310058 加州大学戴维斯分校陆地空气与水资源学院戴维斯95616 加州大学戴维斯分校陆地空气与水资源学院戴维斯 95616 中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室北京100101 加州大学戴维斯分校陆地空气与水资源学院戴维斯95616

土地利用方式影响流域氮输入的空间分布和氮素的迁移输出过程,与非点源污染的防治密切相关。本文利用加州San Joaquin流域数据,考虑不同土地利用方式的影响,在GIS平台上分析了流域氮输入与输出的关系及其空间分布。本文提出了一个新的指... 详细信息

土地利用方式影响流域氮输入的空间分布和氮素的迁移输出过程,与非点源污染的防治密切相关。本文利用加州San Joaquin流域数据,考虑不同土地利用方式的影响,在GIS平台上分析了流域氮输入与输出的关系及其空间分布。本文提出了一个新的指标(F=CN/(L/Q))来衡量河流氮输出的变化趋势,该指标综合考虑了田间产流和河道输移两个过程的影响因子,能够描述土地利用类型对流域氮素迁移转化的影响。在实例研究中,通过该指标能够指示出研究区氮素流失的高风险区,为流域土地利用规划和非点源污染防治提供了重要的科学依据。

关键词：土地利用流域氮平衡河流氮输出 San Joaquin流域

Soil Biogeochemical Cycle Couplings Inferred from a Function-Taxon Network

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Research 2021年第1期2021卷 432-441页

作者： Bin Ma Erinne Stirling Yuanhui Liu Kankan Zhao Jizhong Zhou Brajesh K.Singh Caixian Tang randy a.dahlgren Jianming Xu Institute of Soil and Water Resources and Environmental Science College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment Zhejiang UniversityHangzhou 310058China Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 310058China Acid Sulfate Soils Centre School of Biological SciencesThe University of AdelaideAdelaideSA 5005Australia Institute for Environmental Genomics Department of Microbiology and Plant Biologyand School of Civil Engineering and Environmental SciencesUniversity of OklahomaNormanOKUSA Global Centre for Land-Based Innovation Hawkesbury Institute for the EnvironmentWestern Sydney UniversityPenrithNSW 2750Australia Department of Animal Plant and Soil SciencesLa Trobe UniversityMelbourne CampusBundooraVIC 3086Australia Department of Land Air and Water ResourcesUniversity of CaliforniaDavis95616 CAUSA

Soil biogeochemical cycles and their interconnections play a critical role in regulating functions and services of environmental ***,the coupling of soil biogeochemical processes with their mediating microbes remains poorly ***,we identified key microbial taxa regulating soil biogeochemical processes by exploring biomarker genes and taxa of contigs assembled from metagenomes of forest soils collected along a latitudinal transect(18°N to 48°N)in eastern *** environmental and soil factors,soil pH was a sensitive indicator for functional gene composition and diversity.A function-taxon bipartite network inferred from metagenomic contigs identified the microbial taxa regulating coupled biogeochemical cycles between carbon and phosphorus,nitrogen and sulfur,and nitrogen and *** results provide novel evidence for the coupling of soil biogeochemical cycles,identify key regulating microbes,and demonstrate the efficacy of a new approach to investigate the processes and microbial taxa regulating soil ecosystem functions.

关键词： soil forest Soil

Changes in profile distribution and chemical properties of natural nanoparticles in paddy soils as affected by long-term rice cultivation

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Pedosphere 2021年第5期31卷 659-669页

作者： Dan HUANG Xinyu ZHU Baile XU Yan HE Mingkui ZHANG Fei LIU Zhenghua LIAN randy Adahlgren Philip CBROOKES Jianming XU Institute of Soil and Water Resources and Environmental Science College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058(China) Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment Hangzhou 310058(China) Department of Land Air and Water ResourcesUniversity of California-DavisDavis CA 95616(USA)

Systematic studies on the genesis,properties,and distribution of natural nanoparticles(NNPs)in soil remain *** study examined a soil chronosequence of continuous paddy field land use for periods ranging from 0 to 1000 years to determine how NNPs in soil changed at the early stages of soil genesis in eastern *** samples were collected from coastal reclaimed paddy fields that were cultivated for 0,50,100,300,700,and 1000 *** nanoparticles were isolated and characterized along with bulk soil samples(<2-mm fraction)for selected physical and chemical *** NNP content increased with increasing soil cultivation age at 60 g m^(-2) year-1,which was related to decreasing soil electrical conductivity(172-1297μS cm^(-1))and NNP zeta potentials(from -22 to -36 mV)with increasing soil cultivation *** in several NNP properties,such as pedogenic iron oxide and total organic carbon contents,were consistent with those of the bulk soils across the soil ***,changes in NNP iron oxide content were obvious and illustrated active chemical weathering,pedogenesis,and potential impacts on the microbial *** analysis demonstrated that the soil cultivation age was the most important factor affecting NNP properties,contributing 60.7% of the total *** and principal component analysis(PCA)revealed splitting of NNP samples into age groups of 50-300 and 700-1000 years,indicating rapid evolution of NNP properties,after an initial period of desalinization(approximately 50 years).Overall,this study provides new insights into NNP evolution in soil during pedogenesis and predicting their influences on agriculture and ecological risks over millennial-scale rice cultivation.

关键词： natural nanoparticle evolution soil chronosequence soil cultivation age soil genesis soil nanoparticles

Magnetic effervescent tablets containing ionic liquids as a non-conventional extraction and dispersive agent for determination of pyrethroids in milk

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Magnetic effervescent tablets containing ionic liquids as a ...

Transforming nanoscale VO_(2)(B) into a scalable sodium-ion electrode

中国营养学会第十次特殊营养学术会议

作者： Peipei Zhou Man Gao Jingang Qu Zhanen Zhang randy a.dahlgren Yanyan Li Wei Liu Hong Huang Xuedong Wang Key Laboratory of Watershed Sciences and Health of Zhejiang Province College of Public Health and Management Wenzhou Medical University College of Environmental Sciences and Engineering Suzhou University of Science and Technology

Previously reported magnetic effervescent tablet microextraction procedures have a series of drawbacks, such as slow effervescence, not practicable for field processing, rapid moisture absorption, and poor tablet storage characteristics. To address these shortcomings, we developed a novel magnetic effervescent tablet containing ionic liquid microextraction(MET-ILM) for determination of pyrethroids in dairy milk. The MET-ILM method contains only NaCO as an alkali source(no acidic source) in the FeO magnetic tablet. The CO-forming reaction is initiated in the acidic solution containing the analytes, and thus the prepared tablet can be stored for long time periods without deterioration. Because the ionic liquids(ILs) are added to the tablet, the combined action of ILs(extractant) and magnetic nanoparticles(sorbent) greatly increase the extraction efficiency. Given the simple apparatus required(a centrifuge tube, a magnet and magnetic tablets prepared in advance), the method is very feasible for use in the field. The optimized MET-ILM procedure consisted of a 0.1866 g effervescent tablet(8-mm-diameter ×2-mm-thickness), 2:1 HCl:NaCO, 60 μL [CMIM]PF as extraction solvent, 2-min water-bath at 60℃, and 2% NaCl. Under optimized conditions, LODs for five pyrethroids ranged from 0.024 to0.075 μg kg with extraction recoveries between 78.3 and 101.8%. The RSDs were less than 4.8% for intra-day repeatability precision, and no greater than 6.3% for inter-day reproducibility precision. Overall, this simple method provides a rapid, sensitive, and environmentally benign technique for pyrethroid extraction, and therefore it has great prospects for application in food and environmental detection of trace pesticides under field conditions.

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Nano Research 2024年第10期17卷 8809-8818页

作者： Yunkai Luo Swetha Chandrasekaran Bintao Hu randy Chen Marcus Worsley Bruce Dunn Department of Materials Science and Engineering University of CaliforniaLos AngelesCA 90095USA Lawrence Livermore National Laboratory CA 94550USA

The intermittent nature of renewable energies requires highly reliable grid-level energy storage approaches.A critical consideration in developing this technology is the areal capacity which determines battery performance and influences the cost of battery *** related importance is finding new ways of developing scalable *** recent years,threedimensional(3D)printing of conductive scaffolds has emerged as an alternative to overcome the scalability limitations of commercial tape cast *** research carried out in the current study demonstrates a successful scalability pathway for nanoscale VO_(2)(B),a desirable cathode for sodium-ion batteries which has a nano-flower morphology with a crystallite size<20 *** electrodepositing VO_(2)(B)onto a graphene aerogel scaffold,we were able to achieve mass loading of over 100 mg·cm^(-2) and still possess an areal capacity of 10 mAh·cm^(-2) at a current density of 5 mA·cm^(-2).Moreover,after 1000 cycles,these electrodes retained 75% to 80% of their initial *** at high loading levels,the electrodeposited VO_(2)(B)exhibits pseudocapacitive material signatures such as a box-like voltammetry response,linear galvanostatic response,and no phase change upon *** scalability of the VO_(2)(B)electrode is demonstrated in a series of experiments which show the areal capacity to scale upon increase in both mass loading and electrode thickness,with only small changes in specific *** study establishes that nanoscale materials can be scaled up to achieve thick electrodes without compromising their electrochemical properties.

关键词： nano VO_(2)(B) sodium-ion battery scalable electrodes three-dimensional(3D)printed scaffold additive manufacturing

Non-Linear Matrix Completion

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Journal of Data Analysis and Information Processing 2024年第1期12卷 115-137页

作者： Fengrui Zhang randy C. Paffenroth David Worth Worcester Polytechnic Institute Worcester MA USA

Current methods for predicting missing values in datasets often rely on simplistic approaches such as taking median value of attributes, limiting their applicability. Real-world observations can be diverse, taking stock price as example, ranging from prices post-IPO to values before a company’s collapse, or instances where certain data points are missing due to stock suspension. In this paper, we propose a novel approach using Nonlinear Matrix Completion (NIMC) and Deep Matrix Completion (DIMC) to predict associations, and conduct experiment on financial data between dates and stocks. Our method leverages various types of stock observations to capture latent factors explaining the observed date-stock associations. Notably, our approach is nonlinear, making it suitable for datasets with nonlinear structures, such as the Russell 3000. Unlike traditional methods that may suffer from information loss, NIMC and DIMC maintain nearly complete information, especially in high-dimensional parameters. We compared our approach with state-of-the-art linear methods, including Inductive Matrix Completion, Nonlinear Inductive Matrix Completion, and Deep Inductive Matrix Completion. Our findings show that the nonlinear matrix completion method is particularly effective for handling nonlinear structured data, as exemplified by the Russell 3000. Additionally, we validate the information loss of the three methods across different dimensionalities.

关键词： Matrix Completion Data Pipeline Machine Learning

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加拿大央行打响了背离美联储的第一枪

商业周刊（中文版） 2024年第9期 20-22页

作者： Erik Hertzberg randy Thanthong-Knight Jay Zhao-Murray 杨(译) 不详

加拿大央行行长蒂夫·麦克勒姆明确表示,尽管加元可能面临下行压力,但加拿大的利率政策不需要与美国亦步亦趋。加拿大央行行长蒂夫·麦克勒姆(Tiff Macklem)率先在七国集团(G-7)中降息,他对这一举措的信心,或有助于让其他央行放下心来,... 详细信息

加拿大央行行长蒂夫·麦克勒姆明确表示,尽管加元可能面临下行压力,但加拿大的利率政策不需要与美国亦步亦趋。加拿大央行行长蒂夫·麦克勒姆(Tiff Macklem)率先在七国集团(G-7)中降息,他对这一举措的信心,或有助于让其他央行放下心来,他们也可以在美联储之前降息。

关键词：七国集团克勒姆降息利率政策央行第一枪美联储加拿大

Empowering Rice Farmers in Nueva Ecija, Philippines: A Strategic Approach to Boosting Income through Special Purpose Rice Production

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Open Journal of Ecology 2024年第3期14卷 199-214页

作者： Armando C. Lagasca Eugenia G. Baltazar Johnah Jefferson S. Mercado randy L. Kwan Erwin M. Valiente Jerski Jarzen C. Duria University Extension Program Office Central Luzon State University Science City of Mu&#241oz Philippines Department of Agri-Management College of Agriculture Central Luzon State University Science City of Mu&#241oz Philippines Department of Social Science College of Arts and Social Sciences Central Luzon State University Science City of Mu&#241oz Philippines

Low income is the main problem of millions of farmers who are cultivating 4.81 million hectares in the Philippines. This problem is attributed to challenges specifically low yield, low quality of produce, and significant post-harvest losses, particularly in a resource-scarce setting. This study aimed to help increase the farmers’ income in selected towns of Nueva Ecija through the promotion and use of special purpose rice production technology. Twenty (20) farmer-cooperators in three towns of Nueva Ecija were selected to demonstrate the production technology covering a total area of 4.75 hectares during the dry season, and 3.3 hectares during the wet season, both in 2023. Extension modalities such as training, techno-demo establishment, information material and technical assistance provision, and market linkage were undertaken to enhance their knowledge, attitude, and skills on special rice production and enterprise. The study utilized the descriptive quantitative method wherein the data were gathered through surveys, specifically personal interviews. Results showed that 70% of the farmer-cooperators were male and 60% were living below the poverty threshold. The farmers were 53 years old on average and engaged in farming as their primary source of income. The average yield of special purpose rice particularly the CLS-2 variety was higher (6.46 MT/ha and 6.22 MT/ha during dry and wet seasons, respectively) than that of inbred or non-special rice. The income per hectare from special purpose rice production per hectare was Php 75,420.00, which is higher than that of regular rice at Php 29,389.00, giving a higher benefit of Php 46,031.00. The technology adopters and area planted increased (from 6 to 9 and from 1.4 hectares to 2.75 hectares, respectively) in Licab, Nueva Ecija. The opposite was true in Sto. Domingo and Guimba, Nueva Ecija where farmers were discouraged by the marketing issues that arose.

关键词： Special Purpose Rice Technology Promotion Extension Modality