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Spatial-temporal Characteristics of Holocene Paleosols in the Chinese Loess Plateau and Paleoclimatic Significance

Chinese Geographical Science 2022年第6期32卷 1110-1118页

作者： guo xuelian HE Lusheng ZHAO guoyong WANG Weibin CAO Huairen WU Hao Key Laboratory of Western China’s Mineral Resources of Gansu Province School of Earth SciencesLanzhou UniversityLanzhou 730000China College of Urban and Environmental Science Xinyang Normal UniversityXinyang 464000China

The evolution of Holocene climate was investigated using grain size and magnetic susceptibility of the Holocene paleosols from Baicaoyuan(BCY),Xifeng(XF) and Linyou(LY) sections in the northwest,central and southern Chinese Loess Plateau(CLP).The results show that the Holocene in the B CY,XF and LY paleosol sections could be divided into three phases:during the early Holocene(11.8-10.5 kyr B.P.),increased magnetic susceptibility(χ) and frequency-dependent magnetic susceptibility(χ) and decreased median grain size(Md) indicate that the East Asian Summer Monsoon(EASM) has become more intense and the climate has changed from cold to warm.During the middle Holocene(10.5-5.0 kyr B.P.),the values of χ,χand 2-5 μm grain-size fraction(GT2/5) are higher and Md and 30-63 μm grain-size fraction(GT3 0/6 3) are the lowest,which reflect a warm and humid regional climate.At~8.0 kyr B.P.,there was a transient dry-cold climatic spike corresponding to a Heinrich Event,the cold event was likely due to the collapse of the Laurentide ice sheet.During the late Holocene(5.0-0 kyr B.P.),χ and χvalues are the lowest,while Md and GT30/63 are high,as proxies of a weakened EASM,when the dry-cold climate prevailed in the region.Decreased irradiance since 5.0 kyr B.P.may have caused climatic cooling and drying.Spatially,the increased main peak values and skewness from BCY,XF to LY sections show that the grain size became fine,the East Asian Winter Monsoon(EAWM) reduced,and climate was warmer and wetter from northwest to southeast.In addition,Md can be used as alternative proxy for EAWM,while χis positive with the intensity of EASM under semiarid climate conditions in CLP.

关键词： Holocene magnetic susceptibility grain size paleoclimate Chinese Loess Plateau(CLP)

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Influence of environment and substrate quality on the decomposition of wetland plant root in the Sanjiang Plain,Northeast China

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Journal of Environmental Sciences 2008年第12期20卷 1445-1452页

作者： guo, xuelian LU, Xianguo TONG, Shouzheng DAI, guohua College of Urban and Environmental Sciences Northeast Normal University Changchun 130024 China Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130012 China

The litterbag method was used to study the decomposition of wetland plant root in three wetlands along a water level gradient in the Sanjiang Plain,Northeast China.These wetlands are Calamagrostis angustifolia(C.aa),Carex meyeriana(C.ma)and Carex lasiocarpa (C.la).The objective of our study is to evaluate the influence of environment and substrate quality on decomposition rates in the three wetlands.Calico material was used as a standard substrate to evaluate environmental influences.Roots native to each we...

关键词： wetland plant root decomposition environment quality substrate quality Sanjiang Plain

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黄河口咸淡水交互作用对芦苇湿地土壤有机碳空间分异的影响

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应用生态学报 2024年第2期35卷 415-423页

作者：于淼郭雪莲栗云召张昆杜朝红西南林业大学湿地学院国家高原湿地研究中心昆明650224 鲁东大学滨海生态高等研究院山东烟台264025

河口湿地具有显著的咸淡水交互特征和长期持续的固碳能力。本研究以黄河口咸淡水交互区芦苇湿地作为研究对象,在弱强度交互区、中等强度交互区、较高强度交互区和高强度交互区布设60个研究点位,分析咸淡水交互作用对土壤有机碳空间分异... 详细信息

河口湿地具有显著的咸淡水交互特征和长期持续的固碳能力。本研究以黄河口咸淡水交互区芦苇湿地作为研究对象,在弱强度交互区、中等强度交互区、较高强度交互区和高强度交互区布设60个研究点位,分析咸淡水交互作用对土壤有机碳空间分异的影响。结果表明:黄河口咸淡水交互区芦苇湿地面积占比为17.8%,主要分布在弱强度交互区和中等强度交互区。咸淡水交互区芦苇湿地0~60 cm土层有机碳含量在1.09~3.65 g·kg^(-1),有机碳密度在1.85~5.84 kg·m^(-2),有机碳总储量为(17.32±3.64)×10^(4)t,有机碳含量与密度均随着咸淡水交互作用的增强而降低。咸淡水交互区分区间表层土壤有机碳含量差异显著,随着咸淡水交互强度的增大,表层土壤有机碳含量明显减低。有机碳密度与土壤有机碳、总氮、铵态氮及生物量呈显著正相关,而与盐离子、土壤容重、pH及电导率呈显著负相关。0~30 cm土层有机碳储量占0~60 cm土层有机碳储量的50.9%~64.2%,0~60 cm土层有机碳储量占0~400 cm土层有机碳总储量的19.1%~37.7%。研究结果可为准确评估河口湿地碳储量、提升碳汇功能及湿地管理提供科学依据。

关键词：黄河口咸淡水交互作用芦苇湿地有机碳储量空间分异

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Susceptibility variations of multiple origins of loess from the Ily Basin(NW China)

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Chinese Science Bulletin 2012年第24期57卷 1844-1855页

作者： CHEN Qu LIU XiuMing HELLER F HIRT Ann M LU Bin guo xuelian MAO XueGang ZHAO guoYong FENG Hua guo Hui Key Laboratory of Western China's Environmental Systems Lanzhou UniversityLanzhou 730000China Institute of Geophysics ETHZCH-8092Switzerland School of Geographical Sciences Fujian Normal UniversityFuzhou 350007China Department of Environment and Geography Macquarie UniversitySydney NSW 2109Australia

The magnetic susceptibility of loess from the Ily Basin,northwestern China shows maximum values in S0 paleosols but minimum values in other paleosols,the mechanism of which has been well debated.In this work,systematic magnetic measurements were made on a representative section from Neleke county.The results show that the loess horizons(L1,L2 and L3) have multi-domain magnetite grains of aeolian origin,S0 is characterized by production of pedogenetic ultrafine-grained ferrimagnetic minerals,and the other paleosols(S1,S2,and S3) are characterized by the formation of nonferrimagnetic minerals associated with waterlogging.The correlation between the low concentration of ferrimagnets,high paramagnetic content,high magnetic coercivity remanence,fine ferrimagnetic grain size and intensified pedogenesis suggest two competing processes of pedogenetic enhancement and pedogenetic depletion in the lower paleosols.Pedogenetic depletion dominates and is responsible for the low susceptibility.Changes in magnetic grain size distribution occur during pedogenetic depletion.The susceptibility variations are of multiple origins in the loess of the Ily Basin.Pedogenetic enhancement,pedogenetic depletion,and allochthonous input of magnetic minerals should all be taken into account to explain the variations of magnetic parameters.

关键词：中国西北地区磁化率黄土盆地铁磁性矿物颗粒尺寸分布成土作用土壤发生学

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土地利用方式对纳帕海湿地土壤碳氮储量的影响

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生态学杂志 2024年第6期43卷 1720-1727页

作者：李文韬胡尊英张昆李丽萍仇玉萍郭雪莲云南省高原湿地保护修复与生态服务重点实验室昆明650224 西南林业大学湿地学院昆明650224 浙江科技学院环境与资源学院杭州310023 浙江省生态环境监测中心杭州310012

近年来,受气候变化和人为活动的影响,滇西北高原湿地土地利用方式发生了改变。然而,关于土地利用方式对滇西北高原湿地土壤碳、氮储量的影响及机制尚不明确。本研究选取纳帕海的湿地、草甸和耕地为对象,分析不同土地利用方式和不同土层... 详细信息

近年来,受气候变化和人为活动的影响,滇西北高原湿地土地利用方式发生了改变。然而,关于土地利用方式对滇西北高原湿地土壤碳、氮储量的影响及机制尚不明确。本研究选取纳帕海的湿地、草甸和耕地为对象,分析不同土地利用方式和不同土层深度土壤有机碳(TOC)、全氮(TN)含量和储量的变化特征,阐明不同土地利用方式土壤碳、氮储量与生物量和土壤理化性质之间的耦合关系,探讨纳帕海土地利用方式对土壤碳氮储量影响的机制及主控因子。结果表明:湿地土壤的含水率、TOC、TN含量、地上生物量和地下生物量均显著高于耕地和草甸(P耕地>草甸,表明湿地排水疏干变为草甸或开垦为耕地,将导致纳帕海土壤碳和氮的损失。

关键词：土地利用方式土壤碳储量土壤氮储量纳帕海

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牛冠状病毒S和HE蛋白研究进展

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中国畜牧兽医 2024年第7期51卷 3118-3127页

作者：靳双媛杜家伟王雪妍郭雪莲许立华宁夏大学动物科技学院银川750021

牛冠状病毒(Bovine coronavirus,BCoV)是引起新生犊牛腹泻、牛的呼吸道感染和成年牛冬痢的一种病原,主要通过粪-口感染和呼吸道气溶胶传播。研究表明,BCoV在亚临床感染的成年牛体内可持续存在,这可能是BCoV在牛群中广泛存在且能长期循... 详细信息

牛冠状病毒(Bovine coronavirus,BCoV)是引起新生犊牛腹泻、牛的呼吸道感染和成年牛冬痢的一种病原,主要通过粪-口感染和呼吸道气溶胶传播。研究表明,BCoV在亚临床感染的成年牛体内可持续存在,这可能是BCoV在牛群中广泛存在且能长期循环的原因。因此,BCoV的流行会对集约化牛场造成巨大的经济损失,BCoV的防控形势极其严峻。BCoV S蛋白包含主要的抗原位点,可与宿主表面的唾液酸(SA)结合,且S蛋白参与病毒与宿主细胞的吸附和膜融合过程,能促进宿主产生有效的中和抗体。BCoV HE蛋白具有乙酰酯酶活性和血凝活性,能与S蛋白协同附着于细胞表面并启动感染。S和HE蛋白均在病毒的组织或宿主嗜性及毒力等方面发挥重要作用,这些作用也为进一步开展BCoV病原研究及后续疫苗和药物的研制提供参考。笔者重点阐述了BCoV S和HE蛋白的分子结构及功能,以及BCoV基于S和HE蛋白的受体识别作用(包括利用N-乙酰-9-O-乙酰神经氨酸为糖结合受体,利用人类白细胞抗原Ⅰ类分子为蛋白结合受体)。受体识别是冠状病毒感染和致病的重要决定因素,也是宿主免疫监视和人类干预策略最重要的靶标之一。因此,充分了解BCoV S和HE蛋白的结构功能和受体识别作用对于了解病毒的致病机制及抗病毒药物、疫苗的研发具有重要意义。

关键词：牛冠状病毒(BCoV) S蛋白 HE蛋白受体识别

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Research status and prospect of wind-vehicle-bridge coupling vibration system

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第3期9卷 319-338页

作者： Wanshui Han Xiaodong Liu xuelian guo Shizhi Chen Gan Yang Huanju Liu School of Highway Chang'an UniversityXian 710064China Department of Civil and Environment Engineering University of CaliforniaLos AngelesCA 90015USA School of Civil Engineering Hebei University of EngineeringHandan 056038China

To promote and develop the theoretical basis and application of the wind-vehicle-bridge coupling vibration system,the corresponding research status and prospects are reviewed and discussed from five aspects,i.e.,the analytical framework,the aerodynamic interference,the evaluation criteria,the design loads of long-span bridge and the double-deck railcum-road bridge.The refining process of analysis system is reviewed from the aspects of simulation wind load,vehicle load and bridge structure,and the corresponding coupling relationship.For aerodynamic interference,the development process is summarized from the simulative precision of the elements(wind,vehicle and bridge),the load cases and the object of interference.For evaluation criteria,the corresponding development course is summarized from the certain evaluation method to uncertain one.For long-span bridge design load,the wind and vehicle loads are reviewed and summarized from current multinational codes and theoretical research.For double-deck rail-cum-road bridge,the mechanism of multi-element coupling relationship and corresponding aerodynamic interference are both reviewed.By comprehensive review and summary,the analytical framework is in the process from simplification to refinement.The simulation and consideration of the objects of structural interference gradually become complex.The corresponding simulation theory,wind tunnel scale,test equipment and technology are the key factors to limit its development.For systematic evaluation of vehicle and bridge,the structural and systemic security are the basis of the evaluation,and the auxiliary components and functional evaluation need to be paid more attention.The evaluation criterion will be developed from certain method to reliability assessment.For design load of long-span bridge,the vehicle load is gradually transferred from the simple application of the design load of small-medium span bridge into a complex model considering the load characteristics.For double-deck rail-cum-road bridge,the basic theory and

关键词： Bridge engineering Wind-vehicle-bridge coupling vibration Aerodynamic interference Double-deck rail-cum-road bridge Design loads of long-span bridges Evaluation rule

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Functional conservation and divergence of miR156 and miR529 during rice development

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The Crop Journal 2023年第3期11卷 692-703页

作者： Yan Li Yizhou He Tian Qin xuelian guo Kun Xu Chunxue Xu Wenya Yuan State Key Laboratory of Biocatalysis and Enzyme Engineering Hubei Collaborative Innovation Center for Green Transformation of Bio-ResourcesSchool of Life SciencesHubei UniversityWuhan 430062HubeiChina Oil Crops Research Institute of Chinese Academy of Agricultural Sciences Wuhan 430062HubeiChina Wuhan City Vocational College Wuhan 430064HubeiChina

MicroRNAs(miRNAs)are important regulatory elements involved in the regulation of various plant developmental and physiological processes by blocking the expression of target genes.MiR156 and miR529 are two combinatorial regulators,which cooperatively target the SQUAMOSA PROMOTER BINDING-LIKE(SPL)family genes.However,there has been no report about the functional conservation and divergence of miR156 and miR529 during plant development to date.In this study,the biological function and relationship of miR156,miR529 and their target Os SPL14 in rice were explored.Overexpression of miR156e or miR529a(miR156e-OE and miR529a-OE)increased the grain size and tiller number but decreased the plant height and panicle length,while an opposite phenotype was observed for their target mimicry(miR156-MIMIC and miR529a-MIMIC)transgenic plants.Stem-loop RT-PCR results revealed ubiquitous expression of miR156 in roots,axillary buds and leaves,while miR529 was preferentially expressed in the panicle.Accordingly,Os SPL14 could be preferentially and precisely cleaved by miR529a in young panicle but by miR156 in vegetative tissues.Transgenic plants generated by the target immune strategy exhibited obvious growth defects upon the blocking of miR156 and/or miR529 function in rice,confirming that both miR156 and miR529 play important roles in controlling rice growth and development.Moreover,the miR156/miR529-Os SPL14 module negatively controlled grain size by regulating the genes associated with grain size and cell cycling,and controlled plant height through a more complicated mechanism.Taken together,our results demonstrate that miR156 and miR529 respectively function dominantly in the vegetative stage and reproductive stage to control rice growth and development by regulating the accumulation of Os SPL14.These findings facilitate a better understanding of the functional conservation and divergence of miR156 and miR529 family in the miRNA combinatorial regulatory network of plants.

关键词： MiRNA OsSPL14 Tiller number Grain size Oryza sativa

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牛呼吸道合胞体病毒G和F蛋白的生物学功能

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畜牧兽医学报 2024年第4期55卷 1478-1487页

作者：郭雪莲李永琴李瑞乾李昊靳双媛王雪妍杜家伟许立华宁夏大学动物科技学院银川750021

牛呼吸道合胞体病毒(bovine respiratory syncytial virus, BRSV)是一种在世界范围内引起牛呼吸道疾病的病毒性病因之一,主要引起1岁龄以下犊牛的严重下呼吸道感染。BRSV共编码9种结构蛋白,其中附着蛋白(G蛋白)和融合蛋白(F蛋白)是BRSV... 详细信息

牛呼吸道合胞体病毒(bovine respiratory syncytial virus, BRSV)是一种在世界范围内引起牛呼吸道疾病的病毒性病因之一,主要引起1岁龄以下犊牛的严重下呼吸道感染。BRSV共编码9种结构蛋白,其中附着蛋白(G蛋白)和融合蛋白(F蛋白)是BRSV表面主要的包膜糖蛋白,参与病毒吸附、融合宿主细胞的过程。G和F蛋白含多种识别表位,能够刺激机体产生中和抗体反应,常常是牛呼吸道合胞体病(bovine respiratory syncytial disease, BRSD)疫苗开发所关注的重点。探究G和F蛋白在BRSV侵染中的作用机理对于病毒致病机理分析、疫苗开发具有重要意义。本文旨在对牛呼吸道合胞体病毒G和F蛋白的结构功能及有关疫苗的开发加以综述,以期为BRSV疫苗的研制和BRSD的防控提供参考。

关键词：牛呼吸道合胞体病毒(BRSV) 牛呼吸道合胞体病(BRSD) 附着蛋白(G蛋白) 融合蛋白(F蛋白) 疫苗

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牛呼吸道合胞体病毒一步法实时荧光定量PCR检测方法的建立及应用

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畜牧与兽医 2024年第3期56卷 94-98页

作者：梁晓珊宁鹏李小龙鲍显伟李昊石亚楠王雪妍郭雪莲许立华宁夏大学动物科技学院宁夏银川750021

为建立一种牛呼吸道合胞体病毒(Bovine respiratory syncytial virus, BRSV)快速简便的检测方法,本研究基于BRSV M基因保守区序列,设计特异性引物及探针,通过优化反应条件,建立用于BRSV检测的一步法实时荧光定量PCR,并验证了该方法的敏... 详细信息

为建立一种牛呼吸道合胞体病毒(Bovine respiratory syncytial virus, BRSV)快速简便的检测方法,本研究基于BRSV M基因保守区序列,设计特异性引物及探针,通过优化反应条件,建立用于BRSV检测的一步法实时荧光定量PCR,并验证了该方法的敏感性、特异性和重复性;同时利用建立的检测方法对采集的临床样本进行检测。结果表明:本研究所建立的BRSV荧光定量检测方法,其特异性好,仅对BRSV存在特异性扩增;敏感性高,最低可达10 copies/μL;稳定性好,组内变异系数和组间变异系数小。使用所建立的BRSV一步法实时荧光定量PCR对宁夏地区94份临床样品进行检测,阳性率为5.3%(5/94)。上述结果表明,本研究建立的检测方法可为BRSV的快速诊断提供有力的技术支持。

关键词：牛呼吸道合胞体病毒实时荧光定量PCR M基因诊断

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