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Soil Quality in Relation to Agricultural Production in the North China Plain

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Pedosphere 2015年第4期25卷 592-604页

作者： XIA Min Zhao Bingzi xiying hao ZHANG Jiabao State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences College of Public Administration Nanjing Agricultural University Agriculture and Agri-Food Canada Lethbridge Research Centre

Sustainable agricultural production is of vital importance to food supply security. This study aimed to investigate crop yield response to spatial variability of soil quality at a county scale in the North China Plain （NCP） and subsequently derive key soil quality indicators. Soil samples were geo-referenced and taken in 2008 from both surface （0-20 cm） and subsurface （20-40 cm） layers in 132 fields throughout the Fengqiu County, located in the centre of the NCP, for subsequent soil properties＇ analyses. Annum crop yields were obtained from the same fields where soil samples were collected. Soil quality was evaluated based on a fuzzy set with 13 soil properties, and its spatial distributions were investigated by integrating geostatistical analysis and geographic information system （GIS） techniques. Soil quality indices were classified into five grades, and their spatial distributions were mapped within the county. The surface soil qualities were about one to two grades higher than the subsurface soil. The quality indices for surface and subsurface soils were positively associated with the annual crop yields, suggesting the importance of both. Soil organic matter, total nitrogen, available P, and available K contributed 50% of the combined weight to the soil quality index and were identified as key indicators of soil quality status in the area in terms of sustainability.

关键词： crop yield geostatistical analysis key indicator spatial variability soil quality evaluation soil properties subsurfacesoil surface soil

Nutrient cycling and greenhouse gas emissions from soil amended with biochar-manure mixtures

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Pedosphere 2021年第2期31卷 289-302页

作者： Carlos M.ROMERO Chunli LI Jen OWENS Gabriel O.RIBEIRO Tim A.MCALLISTER Erasmus OKINE xiying hao Agriculture and Agri-Food Canada Lethbridge Research and Development CentreLethbridgeAlberta T1J 4B1(Canada) Department of Biological Sciences Faculty of Arts&SciencesUniversity of LethbridgeLethbridgeAlberta T1K 3M4(Canada) Department of Animal and Poultry Science University of SaskatchewanSaskatoonSaskatchewan S7N 5A8(Canada)

Integrating biochar into cattle diets has recently emerged as a potential management practice for improving on-farm ***,information concerning the cycling of biochar-manure mixtures is scarce.A 70-d incubation experiment was conducted within two surface(0–15 cm)Mollisols with contrasting textures,i.e.,sandy clay loam(Raymond)and clayey(Lethbridge),to evaluate the effects of biochar(3 Mg ha^(-1))on cumulative greenhouse gas(GHG)emissions and related fertility attributes in the presence or absence of cattle manure(120 Mg ha^(-1)).Five treatments were included:i)non-amended soil(control,CK),ii)soil amended with pinewood biochar(B),iii)soil amended with beef cattle manure(M)(manure from cattle on a control diet),iv)soil amended with biochar-manure(BM)(manure from cattle on a control diet,with pinewood biochar added at 20 g kg^(-1)of diet dry matter),and v)soil amended with B and M at the aforementioned rates(B+M).A total of 40 soil columns were prepared and incubated at 21℃and 60%–80%water-holding *** average,total CO_(2)fluxes increased by 2.2-and 3.8-fold under manure treatments(i.e.,M,BM,and B+M),within Raymond and Lethbridge soils,respectively,relative to CK and ***,total CH4 fluxes were the highest(P<0.05)in Raymond soil under B+M and BM relative to CK and B,and in Lethbridge soil under M and BM relative to CK and *** Lethbridge soil,application of BM increased cumulative N_(2)O emissions by 1.8-fold relative to *** 70-d incubation,amendment with BM increased(P<0.05)PO_4-P and NO_3-N+NH_4-N availability in Raymond and Lethbridge soils compared with B.A similar pattern was observed for water-extractable organic carbon in both soils,with BM augmenting(P<0.05)the occurrence of labile carbon over CK and *** can be concluded that biochar,manure,and/or biochar-manure have contrasting short-term effects on the biogeochemistry of *** relatively low application rates,biochar does not necessarily counterbalance manure-derived inpu

关键词： animal husbandry black carbon carbon dioxide methane Orthic Black Chernozem soil fertility

集约化生产对农田土壤碳氮含量及δ^(13)C和δ^(15)N同位素丰度的影响

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应用生态学报 2012年第3期23卷 751-757页

作者：杨广容 hao xiying 李春莉王自林李永梅云南农业大学龙润普洱茶学院昆明650201 加拿大农业部农业与食品莱斯布里奇研究所云南农业大学资源与环境学院昆明650201

集约化生产下农田土壤碳、氮含量变化是衡量土壤肥力持久性的重要指标.对常规水稻-蚕豆轮作地、露地蔬菜地、3年塑料大棚地和10年以上塑料大棚地的土壤pH、电导率(EC)、土壤有机碳(SOC)和总氮(TN)含量及δ13C和δ15N同位素丰度进行测定... 详细信息

集约化生产下农田土壤碳、氮含量变化是衡量土壤肥力持久性的重要指标.对常规水稻-蚕豆轮作地、露地蔬菜地、3年塑料大棚地和10年以上塑料大棚地的土壤pH、电导率(EC)、土壤有机碳(SOC)和总氮(TN)含量及δ13C和δ15N同位素丰度进行测定,研究了集约化生产程度对土壤特性的影响.结果表明:与水稻-蚕豆轮作地相比,露地蔬菜地、3年塑料大棚地和10年以上塑料大棚地0～20 cm耕层土壤pH分别降低1.1、0.8和0.7,而土壤EC分别是水稻-蚕豆轮作地的4.2、4.9和5.2倍;土壤碳、氮含量随塑料大棚地生产年限的增加总体上呈先增大后减小的趋势.与水稻-蚕豆轮作地相比,10年以上塑料大棚地0～20、20～40、40～60、60～80、80～100 cm土层的土壤SOC含量分别下降了54%、46%、60%、63%和59%,土壤TN含量分别下降了53%、53%、71%、82%和85%.农田集约化生产程度显著影响土壤SOC、TN含量和δ13C、δ15N丰度,土壤δ13C丰度与SOC含量呈显著负相关.土壤δ13C丰度可作为评价农田土壤碳循环受人为干扰强度的指标.

关键词：集约化生产土壤有机碳总氮 δ13C δ15N

滇池流域农田不同土地利用方式对土壤磷素积累及其吸附的影响

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西北农林科技大学学报（自然科学版） 2012年第7期40卷 156-166页

作者：杨广容 hao xiying 李春莉王自林李永梅云南农业大学龙润普洱茶学院云南昆明650201 云南农业大学资源与环境学院云南昆明650201 加拿大农业部农业与食品莱斯布里奇研究所加拿大阿尔伯塔省莱斯布里奇T1J481

【目的】研究滇池周边不同土地利用方式下土壤基本理化性质和土壤总磷(TP)、有效磷(Olsen-P)、水溶性磷(Water-P)含量在不同土层(0～20,20～40,40～60,60～80,80～100cm)变化状况及其磷吸附特性,旨在阐明农田土地利用方式对滇池流域土... 详细信息

【目的】研究滇池周边不同土地利用方式下土壤基本理化性质和土壤总磷(TP)、有效磷(Olsen-P)、水溶性磷(Water-P)含量在不同土层(0～20,20～40,40～60,60～80,80～100cm)变化状况及其磷吸附特性,旨在阐明农田土地利用方式对滇池流域土壤磷流失的潜在影响。【方法】2009年,在滇池流域选择常规水稻-蚕豆轮作、露地蔬菜、3～5年和10年以上塑料大棚4种土地利用方式下的农田作为研究对象,采集0～100cm土层的土样,测定土壤基本理化性质和不同形态磷含量,用Langmuir方程拟合不同土地利用方式下土壤的磷吸附特性,并对土壤基本理化性质及不同形态磷含量与土壤磷素吸附特征参数土壤磷最大吸附量(Smax)和土壤磷吸附能常数(k)相关性进行分析。【结果】不同土地利用方式对不同土层土壤基本理化性质有明显影响。4种土地利用方式下,农田土壤TP、Ols-en-P和Water-P主要积累于土壤表层(0～20cm)。与常规水稻-蚕豆轮作地相比,露地蔬菜地、10年以上塑料大棚和3～5年塑料大棚表层(0～20cm)土壤的Olsen-P含量分别高达89.86,74.93,45.07mg/kg,均超过土壤磷向周围水体流失的"突变点"。4种土地利用方式农田的Smax和k分别为747～1 533mg/kg和0.08～0.75L/mg,其中露地蔬菜地、3～5年和10年以上塑料大棚表层(0～20cm)土壤的Smax较水稻-蚕豆轮作地显著降低,k值则随土层深度的增加及塑料大棚种植时间的延长而增大;Smax和k与不同土地利用方式下土壤全氮、NH4+-N、NO3--N含量及C/N呈显著相关关系,Olsen-P和Water-P含量与k呈显著负相关关系(r分别为-0.49和-0.52,P<0.05)。【结论】农田土地利用方式由水稻-蚕豆轮作向集约化蔬菜、花卉生产转变,将会引起土壤特性改变、磷素积累及降低土壤对磷吸附,使农田土壤磷向周边水体流失从而增加水体富营养化的环境风险。

关键词：滇池流域土地利用方式磷吸附面源污染

Three-dimensional line-of-sight-angle-constrained leader-following cooperative interception guidance law with prespecified impact time

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Chinese Journal of Aeronautics 2025年第1期38卷 491-506页

作者： hao YOU Xinlong CHANG Jiufen Zhao Rocket Force University of Engineering Xi’an 710025China

To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D leader-following cooperative interception guidance ***,in the LOS direction of the leader,an impact time-controlled guidance law is derived based on the fixed-time stability theory,which enables the leader to complete the interception task at a prespecified impact ***,in the LOS direction of the followers,by introducing a time consensus tracking error function,a fixed-time consensus tracking guidance law is investigated to guarantee the consensus tracking convergence of the ***,in the direction normal to the LOS,by combining the designed global integral sliding mode surface and the second-order Sliding Mode Control(SMC)theory,an innovative 3D LOS-angle-constrained interception guidance law is developed,which eliminates the reaching phase in the traditional sliding mode guidance laws and effectively saves energy ***,it effectively suppresses the chattering phenomenon while avoiding the singularity issue,and compensates for unknown interference caused by target maneuvering online,making it convenient for practical engineering ***,theoretical proof analysis and multiple sets of numerical simulation results verify the effectiveness,superiority,and robustness of the investigated guidance law.

关键词： Three-dimensional cooperative interception Leader-following missiles Prespecified impact time LOS-angle-constrained Fixed-time stability Global integral sliding mode

Omnidirectional simulation analysis of thermomechanical coupling mechanism in inertia friction welding of Ni-based superalloy

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Chinese Journal of Aeronautics 2025年第1期38卷 202-216页

作者： Chang-an LI Guoliang QIN hao WANG School of Materials Science and Engineering Shandong UniversityJinan 250061China

The coupling between heat and pressure is the kernel of inertia friction welding(IFW)and is still not fully understood.A novel 3D fully coupled finite element model based on a plastic friction pair was developed to simulate the IFW process of a Ni-based superalloy and reveal the omnidirectional thermo-mechanical coupling mechanism of the friction *** numerical model successfully simulated the deceleration,deformation processes,and peak torsional moments in IFW and captured the evolution of temperature,contact pressure,and *** simulated results were validated through measured thermal history,optical macrography,and axial *** results indicated that interfacial friction heat was the primary heat source,and plastic deformation energy only accounted for 4%of the *** increase in initial rotational speed and friction pressure elevated the peak temperature,reaching a maximum of 1525.5K at an initial rotational speed of 2000 r/min and friction pressure of 400 *** interface heat generation could form an axial temperature gradient exceeding 320K/*** radial inhomogeneities of heat generation and temperature were manifested in a concentric ring distribution with maximum heat flux and temperature ranging from 2/5 to 2/3 *** radial inhomogeneities were caused by increasing linear velocity along the radius and an opposite distribution of contact pressure,which could reach 1.7 times the set pressure at the *** circumferential inhomogeneity of thermomechanical distribution during rotary friction welding was revealed for the first time,benefiting from the 3D *** deflection and transformation of distribution in contact pressure and Mises stress were indicators of plastic deformation and transition of quasi-steady state *** critical Mises stress was 0.5 times the friction pressure in this *** presented modeling provides a reliable insight into the thermo-mechanical coupling mechanism of IFW and lays a solid found

关键词： Inertia friction welding Thermo-mechanical coupling Inhomogeneity Numerical simulation Ni-based superalloy

Flotation separation of chalcopyrite from pyrite using mineral fulvic acid as selective depressant under weakly alkaline conditions

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中国有色金属学报 2025年第1期35卷 313-325页

作者： Zhi-hao SHEN Shu-ming WEN Jia-mei hao Qi-cheng FENG State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China

Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a *** experiments showed that MFA produced a stronger inhibition effect on pyrite than on *** separation of chalcopyrite from pyrite was realized by introducing 150 mg/L MFA at a pulp pH of approximately *** copper grade,copper recovery,and separation efficiency were 28.03%,84.79%,and 71.66%,*** adsorption tests,zeta potential determinations,and localized electrochemical impedance spectroscopy tests showed that more MFA adsorbed on pyrite than on chalcopyrite,which weakened the subsequent interactions between pyrite and the *** force microscope imaging further confirmed the adsorption of MFA on pyrite,and X-ray photoelectron spectroscopy results indicated that hydrophilic Fe-based species on the pyrite surfaces increased after exposure of pyrite to MFA,thereby decreasing the floatability of pyrite.

关键词： mineral fulvic acid chalcopyrite pyrite flotation separation

Late Paleozoic to early Mesozoic volcanic-sedimentary history of the southeastern margin of the Central Asian Orogenic Belt:Timing of uplift of the Inner Mongolia paleo-uplift

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Science China Earth Sciences 2025年第1期68卷 297-309页

作者： Wenxing hao Jin-Hui YANG Guang ZHU State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China School of Resource and Environmental Engineering Hefei University of TechnologyHefei230009China

The Kulun region is located in the eastern Bainaimiao arc belt on the southeastern margin of the Central Asian Orogenic Belt(CAOB),adjacent to the North China Craton(NCC)to the *** region records the closure of the PaleoAsian Ocean during the Paleozoic to early Mesozoic and is key to study the tectonic evolution of the northern margin of the *** conducted zircon U-Pb geochronology and Hf isotope analysis of volcanic-sedimentary and intrusive rocks in the Kulun *** volcanic-sedimentary rocks were previously assigned an early Carboniferous age,but include volcanic rocks with ages of 267–266 Ma and sedimentary rocks with youngest detrital zircon age peaks of 265–244 Ma,which were intruded by a granite with an age of 242 *** indicates that these rocks are actually middle Permian to Middle Triassic in age(267–242Ma)and correspond to the Qingfengshan and Liujiagou ***,two volcanic rock samples have highεHf(t)values(+1.6 to+16.1)and relatively young two-stage Hf model ages(1095–327 Ma),indicating their sources associated with the *** age spectra and Hf isotopic characteristics of detrital zircons from the sedimentary rocks suggest that,during the middle Permian to Middle Triassic,the sedimentary provenance in the Kulun region was mainly the ***,by the Early Jurassic,the provenance changed to the NCC(i.e.,the Inner Mongolia Paleo-uplift,IMPU).This result,combined with the development of a series of conglomerates on the northern margin of the NCC in the Late Triassic(i.e.,Xingshikou,Xiaoyingzi,and Xiaohekou formations),indicates the Kulun region experienced an abrupt change in paleogeography during the Late Triassic,with the IMPU undergoing significant uplift and thus becoming the main sediment source in the Kulun *** on the Late Triassic alkaline igneous belt(235–215 Ma)in the IMPU,we speculate that this uplift was caused by detachment of the southward-subducting Paleo-Asian oceanic plate,which occurred in a post-o

关键词： Central Asian Orogenic Belt the North China Craton Zircon geochronology Hf isotopes Inner Mongolia Paleo-uplift

Unusual roles of ceria as the support of a single-atom catalyst in hydroisomerization of n-heptane:Phase boundary acts as transport channels between different active centers

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Journal of Rare Earths 2025年第2期43卷 276-283页

作者： hao Qin Hui Wan Guofeng Guan State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringJiangsu National Synergetic Innovation Center for Advanced MaterialsNanjing Tech University

Hydroisomerization of n-alkanes plays an important role in fuel and lubricants *** catalysts with ultralow platinum loading have recently been reported successively for ***,the catalysts were prepared successfully with different methods to improve the catalytic *** conversion of 0.01%Pt1@CeOx/SAPO-11 prepared by co-calcination method（0.01%Pt1@CS-c） is 71.4%,25% higher than the other prepared by precipitation *** turnover frequency per active surface platinum site（TOFPt） of 0.01%Ptl@CS-c is as high as 13115 *** by the X-ray photoelectron spectroscopy（XPS） results,the quality of phase boundary/intersurface between ceria and zeolite is found significantly *** conjunction quality of phase boundary directly affects the spillover rate of intermediate species,which further leads to an apparent activity *** addition,the possible role of ceria in the reaction is discussed,rather than just as a carrier for the active metal atoms.

关键词： Rare earths Hydroisomerization Spillover Proximity Single-atom catalysis Intermediate