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庞泉沟自然保护区森林群落物种多样性

生态学杂志 2009年第12期28卷 2431-2436页

作者：雷淑慧卢爱英张先平王孟本山西林业职业技术学院太原030009 山西大学黄土高原研究所太原030006

以庞泉沟自然保护区海拔1630～2430m的森林群落为研究对象,采用样方法(共取10m×10m样方84个)进行物种组成和环境因子调查,对物种多样性及其与环境因子的关系进行研究。结果表明:(1)随着森林群落垂直分布的变化,即从山体下部(1630～200... 详细信息

以庞泉沟自然保护区海拔1630～2430m的森林群落为研究对象,采用样方法(共取10m×10m样方84个)进行物种组成和环境因子调查,对物种多样性及其与环境因子的关系进行研究。结果表明:(1)随着森林群落垂直分布的变化,即从山体下部(1630～2000m)的华北落叶松灌木群落到山体中部(2000～2200m)的华北落叶松云杉桦木混交林群落,再到山体上部(2200～2430m)的华北落叶松苔草群落,物种丰富度指数(R0)与Shannon-Wiener指数(H)呈现由小增大(在中部达最大)和由大减小的趋势;而Simpson指数(λ)和Pielou均匀度指数(E)则呈现持续增大趋势。(2)海拔与R0(r=-0.541,P1)、H(r=-0.377,P1)呈极显著负相关,与λ(r=0.495,P1)呈极显著正相关;坡向与R0(r=-0.365,P1)呈极显著负相关,与H(r=-0.250,P356,P1)呈极显著正相关;坡度和土层厚度与多样性指数的相关性不显著。(3)乔木层盖度与R0(r=0.238,P17,P381,P1)的相关性显著,而灌木层盖度与各多样性指数的相关性均不显著。

关键词：物种多样性多样性指数森林群落庞泉沟自然保护区海拔

低密度聚乙烯微塑料对土壤中含氧多环芳烃自然衰减的影响

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环境科学 2024年第6期45卷 3688-3699页

作者：汤佳豪鲍文秀张闻李瑜婷古鹏吴济舟卢媛齐鲁工业大学(山东省科学院) 山东省科学院生态研究所山东省应用微生物重点实验室济南250103 国检测试控股集团京诚检测有限公司广州511400 南开大学环境科学与工程学院天津300350

农田土壤中微塑料的不断积累可能会影响含氧多环芳烃(OPAHs)的自然衰减行为.通过土壤微宇宙实验,研究了质量分数为1%和0.01%低密度聚乙烯微塑料(LDPE)对土壤中OPAHs自然衰减的影响,并探究了细菌群落响应与OPAHs自然衰减的关联.土壤中初... 详细信息

农田土壤中微塑料的不断积累可能会影响含氧多环芳烃(OPAHs)的自然衰减行为.通过土壤微宇宙实验,研究了质量分数为1%和0.01%低密度聚乙烯微塑料(LDPE)对土壤中OPAHs自然衰减的影响,并探究了细菌群落响应与OPAHs自然衰减的关联.土壤中初始ω(OPAHs)为34.6 mg·kg^(-1),培养14 d时LDPE抑制了土壤中OPAHs的自然衰减,LDPE处理组ω(OPAHs)较对照组高出0.9~1.6 mg·kg^(-1),抑制程度随LDPE质量分数增大而增大;28 d时3个处理组间土壤中OPAHs含量无显著差异,LDPE抑制效应消失.LDPE处理未改变OPAHs污染土壤中群落优势物种组成,但影响了部分优势物种相对丰度;使门水平上变形菌门和放线菌门等相对丰度增加;使属水平上芽孢杆菌属相对丰度下降,而小单孢菌属、鞘氨醇单胞菌属和硝化螺旋菌属相对丰度增加(为LDPE及内源物的潜在降解菌),这4个菌属均是属水平上主导组间群落差异的主要物种.LDPE使细菌群落的α和β多样性发生了变化,但差异不显著.LDPE影响了细菌群落的功能,降低了多环芳烃降解基因的总丰度及部分降解酶丰度,抑制了多环芳烃降解菌的生长,进而干预了OPAHs自然衰减.

关键词：微塑料(MPs) 低密度聚乙烯(LDPE) 含氧多环芳烃(OPAHs) 自然衰减细菌群落

Tectono-chronologic constraints on a Mesozoic slip and thrust belt in the eastern Jiaodong Peninsula

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Science china Earth Sciences 2007年第1期50卷 25-32页

作者： zhang HongYuan1,2, hou QuanLin3 & CAO DaiYong 4 1 institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, china 2 State Key Laboratory of Geological Processes and Mineral Resources, china university of Geosciences, Beijing 100083, china 3 Graduate School of china Acacemy of Sciences, Beijing 100039, china 4 Key Laboratory of Coal Resources (CUMT), Ministry of Education, Beijing 100083, china 1. institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China 2. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 3. Graduate School of china Academy of Sciences Beijing 100039 China 4. Key Laboratory of Coal Resources (CUMT) Ministry of Education Beijing 100083 China

A major slip and thrust belt within the eastern Jiaodong Peninsula is located at the eastern terminal of the Qinling-Dabie-Sulu orogenic belt between the Sino-Korea Block and yangtze Block. Although a lot of isotope chronologic data have been obtained regionally, little structural chronological research has been conducted in this region and this paper corrects that. Syn-deformational minerals were system-atically selected from samples of the NE-ENE trending transpressional shear zones and transpres-sional nappes and carefully analysed using 40Ar/39Ar methods. Two tectonic events were defined with the first event resulting from early movement of transpressional nappes around 190 Ma ago. This ac-cords with the period of syn-orogenic sinistral slip of the Tan-lu faults and clockwise shear in the Eastern Qinling-Tongbaishan part of the Qinling-Dabie-Sulu orogenic belt. The second event involved strikeslip thrust movement of deep shear zones between 130Ma and 120Ma. This resulted from the onset of Mesozoic tectonic conversion in the eastern Jiaodong Peninsula. The sinistral strikeslip-thrusting in Jiaodong Peninsula and the extensional tectonism (toward ESE) in Liaodong Peninsula probably resulted in the clockwise rotation of Korea Peninsula in late Mesozoic.

关键词： the eastern Jiaodong Peninsula tectono-chronology 40Ar/39Ar strikeslip and thrust belt.

Key indicators affecting maize stalk lodging resistance of different growth periods under different sowing dates

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Journal of Integrative Agriculture 2020年第10期19卷 2419-2428页

作者： WANG Qun xue Jun CHEN Jiang-lu FAN Ying-hu zhang Guo-qiang XIE Rui-zhi MING Bo hou peng WANG Ke-ru LI Shao-kun Key Laboratory of Oasis Eco-Agriculture Xinjiang Production and Construction Corps/agricutura1 CollegeShihezi UniversityShihezi 832000P.R.China institute of Crop Sciences Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Physiology and EcologyMinistry of Agriculture and Rural AffairsBejjing 100081P.R.China Research institute of Agricultural Sciences Sixth Division of Xinjiang Production and Construction CorpsWujiaqu 831300P.R.China Chuxiong State Research and Extension institute of Agricultural Science Chuxiong 675000P.R.China

The accurate evaluation of maize stalk lodging resistance in different growth periods enables timely management of lodging risks and ensures stable and high maize ***,we established five diferent sowing dates to create diferent conditions for maize *** evaluated the effects of the different growth conditions on lodging resistance by determining stalk morphology,moisture content,mechanical strength and dry matter,and the relationship between stalk breaking force and these indicators during the silking stage(R1),milk stage(R3),physiological maturity stage(R6),and 20 days after *** height at R1 positively affected stalk breaking *** R3,the cofficient of ear height and the dry weight per unit length of basal internodes were key indicators of stalk lodging *** R6,the key indicators were the coefficient of the center of gravity height and plant fresh *** R6,the key indicator was the coefficient of the center of gravity *** crushing strength of the fourth internode correlated significanty and positively with the stalk breaking force from R1 to R6,which indicates that crushing strength is a reliable indicator of stalk mechanical *** results suggest that high stalk strength and low ear height beneft lodging resistance prior to *** and after R6,the cofficient of the center of gravity height and the mechanical strength of basal internodes can be used to evaluate plant lodging resistance and the appropriate time for harvesting in fields with a high lodging risk.

关键词： maize lodging resistance stalk strength growth periods breaking force

基于夜间灯光数据的新冠疫情期间环渤海地区经济韧性及影响因素

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人文地理 2024年第4期39卷 46-56,117页

作者：张学波卢冰坤何志浩吴江楠曲阜师范大学地理与旅游学院日照276826 曲阜师范大学黄河生态研究院曲阜273165

基于环渤海地区2019年第四季度至2021年第四季度的夜间灯光数据,剖析了环渤海地区不同时间尺度的经济韧性时空演变特征,探讨了地区经济韧性的主要影响因素。结果表明:(1)季度上,北京、天津经济韧性的时序变化幅度较大;年际上,环渤海地... 详细信息

基于环渤海地区2019年第四季度至2021年第四季度的夜间灯光数据,剖析了环渤海地区不同时间尺度的经济韧性时空演变特征,探讨了地区经济韧性的主要影响因素。结果表明:(1)季度上,北京、天津经济韧性的时序变化幅度较大;年际上,环渤海地区经济韧性时序变化较小。(2)空间上,京津冀城市群北部以及山东省部分地区经济韧性较高,其中京津冀北部地区经济恢复速度较快,持续表现为“高—高”类型集聚。(3)产业结构多样化对地区季度经济韧性产生了抑制性作用,而社会消费与政府调控有利于季度经济韧性的增强;产业结构高级化与年度经济韧性呈倒U型关系,对年度经济韧性的正向影响呈减弱的趋势,技术创新的积极效应存在滞后性。

关键词：环渤海地区经济韧性夜间灯光数据影响因素

Morphological,phylogenetic and metabolite profile of Prorocentrum clipeus,a newly recorded epiphytic dinoflagellate in the northern Yellow Sea

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Acta Oceanologica Sinica 2024年第8期43卷 128-141页

作者： Ruifang Wang Mengmeng Tong Shiwen Zhou Junjie Zheng Wenguang zhang Xinfeng Dai Douding lu Jiarong Hu Tianze Leng Qinglin Mu Zhongyong Yan Jiangning Zeng pengbin Wang Ocean College Zhejiang UniversityZhoushan 316021China Key Laboratory of Marine Ecosystem Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China The State Key Laboratory of Marine Pollution Department of Biomedical SciencesCity University of Hong KongHong Kong SAR 999077China Zhejiang Marine ecology and Environment Monitoring Center Zhoushan 316000China

More than 30 species of benthic Prorocentrum have been identified,some of which produce okadaic acid(OA)and its derivatives,dinophysistoxins(DTXs),which cause diarrhetic shellfish poisoning(DSP).Increasing numbers of benthic Prorocentrum species have been reported in tropical and subtropical waters of *** contrast,only a few benthic Prorocentrum species have been reported in temperate *** this study,morphological descriptions obtained using light microscopy,scanning electron microscopy and molecular characterization of one Prorocentrum clipeus strain isolated from the Yellow Sea are *** clipeus cells were nearly circular in shape,with a collar,ridge,and one *** periflagellar area was wide U-shaped,with two curved projections on platelet *** periflagellar platelets of different sizes were *** morphology closely fits that of the species isolated from other *** analysis based on the molecular sequences of the small subunit(SSU)rDNA,internal transcribed spacer(ITS),and large subunit(LSU)rDNA was performed.A comprehensive metabolomic analysis incorporating target,suspect and non-target screenings was first applied to investigate the intracellular and extracellular metabolite profiles of the current isolate of *** to the results of the target and suspect screenings,179 metabolites or toxins produced by DSP-related algal species,including OA,dinophysistoxin-1(DTX1),dinophysistoxin-2(DTX2)and pectenotoxin-2(PTX2),were not ***-target screening involving feature-based molecular networking(FBMN)provided a global view of major metabolites produced by the *** DF128 strain and revealed 23 clusters belonging to at least 13 compound classes,with organometallic compounds,lipids and lipid-like molecules,phenylpropanoids and polyketides,and benzenoids as major *** date,this is the first record of the characterization of *** in samples from Chinese *** results suppo

关键词： Prorocentrum taxonomy phylogeny metabolite profiling Yellow Sea

东北高产春玉米氮营养指标的无人机多光谱遥感监测

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玉米科学 2024年第4期32卷 92-101页

作者：辛江风明博薛贝贝杨宏业郭慧荣冯大云谢瑞芝王克如侯鹏李少昆禄兴丽宁夏大学农学院银川750021 中国农业科学院作物科学研究所/农业部作物生理生态重点实验室北京100081

为了探究随机森林算法在春玉米氮营养指标预测精度,于2021-2022年在东北地区进行氮肥梯度试验,以迪卡159为试验材料,设置10个施氮水平,利用无人机搭载多光谱分别在小喇叭口期(V9)、大喇叭口期(V12)和抽雄期(VT)获取遥感数据。利用19个... 详细信息

为了探究随机森林算法在春玉米氮营养指标预测精度,于2021-2022年在东北地区进行氮肥梯度试验,以迪卡159为试验材料,设置10个施氮水平,利用无人机搭载多光谱分别在小喇叭口期(V9)、大喇叭口期(V12)和抽雄期(VT)获取遥感数据。利用19个植被指数分别构建地上部生物量(AGB)、植株吸氮量(PNU)、叶面积指数(LAI)和比叶氮(SLN)模型。结果表明,随机森林算法在预测AGB和LAI有较高的精度,R2分别是0.83和0.9。通过相关分析,LAI、AGB、PNU及SLN与结构不敏感色素指数(SIPI)相关性最高,相关系数分别为-0.75、-0.70、-0.84和0.63,SIPI在4个模型中重要性均最高。研究结果表明,随机森林算法在春玉米氮素监测中具有一定的发展潜力,SIPI在氮素监测中有重要作用,研究结果可为春玉米氮素营养监测提供参考依据。

关键词：春玉米多光谱遥感随机森林氮营养指标

The role of bone marrow-derived cells in the origin of liver cancer revealed by single-cell sequencing

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Cancer Biology & Medicine 2020年第1期17卷 142-153页

作者： lu Chen Xianfu Yi Piao Guo hua Guo Ziye Chen Chunyu hou Lisha Qi Yongrong Wang Chengwen Li peng Liu Yucun Liu Yuanfu Xu Ning zhang The concrete information of affiliations should be presented for instanceDepartment of Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjin's Clinical Research Center for CancerTianjin 300070China School of Biomedical Engineering and Technology Tianjin Medical UniversityTianjin 300070China The Center for Translational Cancer Research Peking University First HospitalBeijing 100034China State Key Laboratory of Experimental Hematology National Clinical Research Center for Blood DiseasesInstitute of Hematology&Blood Diseases HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeTianjin 300020China CAMS Key Laboratory for Prevention and Control of Hematological Disease Treatment Related Infection Tianjin 300020China Cytogenetics Laboratory Institute of Hematology and Blood Diseases HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeTianjin 300020China

Objective:Epithelial cancers often originate from progenitor cells,while the origin of hepatocellular carcinoma(HCC)is still ***,one of the deadliest cancers,is closely linked with liver injuries and chronic inflammation,which trigger massive infiltration of bone marrow-derived cells(BMDCs)during liver ***:To address the possible roles of BMDCs in HCC origination,we established a diethylnitrosamine(DEN)-induced HCC model in bone marrow transplanted *** and frozen tissue immunofluorescence were used to verify DENinduced HCC in the pathology of the *** cellular origin of DEN-induced HCC was further studied by single cell sequencing,single-cell nested PCR,and immunofluorescence-fluorescence in situ ***:Studies by using single cell sequencing and biochemical analysis revealed that HCC cells in these mice were coming from donor mice BMDCs,and not from recipient ***,the copy numbers of mouse orthologs of several HCC-related genes previously reported in human HCC were also altered in our mouse ***-induced HCCs exhibited a similar histological phenotype and genomic profile as human ***:These results suggested that BMDCs are an important origin of HCC,which provide important clues to HCC prevention,detection,and treatments.

关键词： Hepatocellular carcinoma bone marrow-derived cells(BMDCs) origination genome sequencing copy number alteration

Air-condition process for scalable fabrication of CdS/ZnS 1D/2D heterojunctions toward efficient and stable photocatalytic hydrogen production

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Carbon Energy 2023年第7期5卷 1-14页

作者： Dongdong zhang Jie Teng Hongli yang Zhi Fang Kai Song Lin Wang Huilin hou Xianlu lu Chris RBowen Weiyou yang College of Materials Science and Engineering Hunan UniversityChangshaPeople's Republic of China institute of Micro/Nano Materials and Devices Ningbo University of TechnologyNingboZhejiangPeople's Republic of China Department of Mechanical Engineering University of BathBathUK

We report the scalable fabrication of CdS/ZnS 1D/2D heterojunctions under ambient air conditions(i.e.,room temperature and atmospheric pressure)in which ZnS nanoparticles are anchored on the surface of CdS *** as-formed heterojunctions exhibit a significantly enhanced photocatalytic H_(2) evolution rate of 14.02 mmol h^(-1) g^(-1) when irradiated with visible light,which is~10 and 85 times higher than those of pristine CdS nanosheets and CdS nanoparticles,respectively,and superior to most of the CdS-based photocatalysts reported to ***,they provide robust photocatalytic performance with demonstratable stability over 58 h,indicating their potential for practical *** formation of 1D/2D heterojunctions not only provides improved exposed active sites that respond to illumination but also provides a rapid pathway to generate photogenerated carriers for efficient separation and transfer through the matrix of single-crystalline CdS *** addition,first-principles simulations demonstrate that the existence of rich Zn vacancies increases the energy level of the ZnS valence band maximum to construct type-II and Z-scheme mixed heterojunctions,which plays a critical role in suppressing the recombination of carriers with limited photocorrosion of CdS to enhance photocatalytic behavior.

关键词： air condition CdS heterojunctions photocatalytic hydrogen production ZnS