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Journal of Geographical Sciences 2025年第1期 39-64页

作者： HE Chenyang WANG Yanjiao YAN Feng LU Qi School of Ecological and Environmental Science East China Normal University institute of Ecological Conservation and Restoration Chinese Academy of Forestry national Climate Center China Meteorological Administration

Water use efficiency （WUE）,as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ***,in the context of global warming,WUE evolution and its primary drivers on the Tibetan Plateau remain *** study employed the ensemble empirical mode decomposition method and the random forest algorithm to decipher the nonlinear trends and drivers of WUE on the Tibetan Plateau in 2001–*** indicated an annual mean WUE of 0.8088 gC/mm·m2across the plateau,with a spatial gradient reflecting decrease from the southeast toward the *** manifesting monotonous trends of increase or decrease in WUE accounted for 23.64%and 9.69%of the total,***,66.67%of the region exhibited trend reversals,i.e.,39.94%of the area of the Tibetan Plateau showed transition from a trend of increase to a trend of decrease,and 26.73%of the area demonstrated a shift from a trend of decrease to a trend of *** factors accounted for 70.79%of the variability in *** leaf area index and temperature served as the major driving forces of WUE variation.

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Extensional Setting of Hainan Island in Mesoproterozoic:Evidence from Granitic Intrusions in the Baoban Group

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Acta Geologica Sinica(English Edition) 2022年第4期96卷 1199-1212页

作者： LIU Yuheng MAO Jingwen QIU Kunfeng HU Jun WANG Lei XU Deming MNR Key Laboratory of Geochemical Exploration Institute of Geophysical and Geochemical ExplorationChinese Academy of Geological SciencesLangfangHebei 065000China UNESCO International Centre on Global-scale Geochemistry LangfangHebei 065000China MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China China University of Geosciences(Beijing) Beijing 100083China State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences and ResourcesChina University of Geosciences(Beijing)Beijing 100083China Frontiers Science Center for Deep Ocean Multispheres and Earth System Key Lab of Submarine Geosciences and Prospecting TechniquesMOE and College of Marine GeosciencesOcean University of ChinaQingdaoShandong 266100China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdaoShandong 266237China Wuhan Center of China Geological Survey(Central South China Innovation Center for Geosciences) Wuhan 430205China

The Mesoproterozoic Baoban Group is the oldest basement in Hainan Island and has played an important role in Columbia(Nuna)supercontinent *** Mesoproterozoic granitic intrusions in the Baoban Group are the most widely-exposed Precambrian magmatic rocks and are the key to understanding the tectonic settings of Hainan Island and its relationship with the South China Block and the Columbia *** LA-ICP-MS zircon U-Pb dating on three mylonitic granite samples from the Tuwaishan and Baoban areas yield ages ranging from 1447 Ma to 1437 Ma,representing the absolute timing of the emplacement of the granitic *** with previously published geochronological data for rocks from the Baoban Group and regional mafic intrusions,it is concluded that the Baoban Group formed at 1460-1430 Ma,coeval with the emplacement of the granitic and mafic *** in-situ zircon LuHf isotope analyses for the three mylonitic granite samples yielded positiveε(t)values,ranging from+0.49 to+8.27,with model ages(T~C)ranging from 2181 Ma to 1687 Ma,suggesting that the granitic intrusions originated from a mixed source of Paleoproterozoic crust with juvenile *** zircon trace element data show characteristics of high Th/U values of 0.24-1.50,steep slopes from LREE to HREE and negative Pr,Eu anomalies with positive Ce,Sm anomalies,representing typical magmatic zircons formed in continental *** with available magmatic and detrital zircon ages from Precambrian rocks in the Cathaysia Block,Yangtze Block and western Laurentia,it is inferred that Hainan Island was separated from both the Cathaysia Block and the Yangtze Block,instead being connected with western Laurentia in the Columbia *** the decreasing tendency of basin deposition time along the western margin of Laurentia,it is proposed that Hainan Island was located to the north or northwest of the Belt-Purcell Supergroup,along the western margin of Laurentia,during

关键词： zircon U-Pb dating Lu-Hf isotopes granitic intrusions Baoban Group extensional setting Hainan Island

Experimental Study of Dissolution-Alteration of Amphibole in a Hydrothermal Environment

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Acta Geologica Sinica(English Edition) 2019年第6期93卷 1933-1946页

作者： LI Yongli HUANG Fei GAO Wenyuan TANG Xu REN Yaqun MENG Lin ZHANG Zhibin Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines and School of Resources and Civil EngineeringNortheastern UniversityShenyang 110819China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Electron Microscope Laboratory Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

Amphibole is a rock-forming mineral widely existing on the *** is easily dissolved and altered during the later stage of diagenesis and mineralization,and often forms chloritization,which is an important indicator for *** explore amphibole's dissolution process and alteration mechanism,dissolution experiments were carried out under acidic conditions using pargasite-rich amphibole as raw material,and the effects of temperature,p H,and experiment duration on amphibole alteration were *** samples and products were analyzed using X-ray diffractometer,field emission scanning electron microscope,electron probe micro analyzer,and transmission electron *** was found that many pores and erosion edges are produced after amphibole dissolution,and there is a clear interface between the dissolved residual portion and the *** dissolved residual portion remains in the amphibole phase,but as the temperature and time increase,the intensity of the diffraction peak of the phase in the product decreases,and the peak position shifts to a small *** clay minerals such as chlorite and griffithite formed on the amphibole *** an environment with strong acidity(p H=3),the amount of chamosite increases with temperature(180℃→210℃→240℃),whereas clinochlore is only increased in a 150–210℃*** growth was observed in the acidic(p H=6)and low temperature(<180℃)*** on this analysis,large radius Cl–enters the amphibole lattice or cracks to promote *** Al-poor and Ca-and Fe-rich regions between the edge and core of the amphibole are caused by dynamic equilibrium in amphibole dissolution and alteration process,which is an essential indicator for the beginning of amphibole *** and the coupled dissolution-reprecipitation mechanism accomplishes the process of dissolution and alteration to form clay *** energy of the system determined by temperature and p H

关键词： hydrothermal environment amphibole dissolution-alteration chlorite griffithite

Two New Sesquiterpene Lactones from Elephantopus tomentosus

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Chinese Journal of Chemistry 2012年第6期30卷 1320-1322页

作者：王蓓梅文莉左文健赵友兴董文化刘国道戴好富 Key Laboratory of Biology and Genetic Resources of Tropical Crops Ministry of AgricultureInstitute of TropicalBioscience and BiotechnologyChinese Academy qf Tropical Agricultural SciencesHaikouHainan 571101China Tropical Crops Genetic Resources institute Chinese Academy of Tropical Agriculture SciencesDanzhouHainan 571737China Horticultural and Garden College Hainan UniversityHaikouHainan 570228China

Phytochemical investigation on the whole plant of Elephantopus tomentosus Linn. led to the isolation of two new sesquiterpene lactones, tomenphantopin E （1） and tomenphantopin F （2）. The new compounds were complet... 详细信息

关键词： sesquiterpene lactone Elephantopus tomentosus tomenphantopin E tomenphantopin F

No consistent daily variation in DNA methylation detected in Populus nigra leaves by methylation-sensitive amplification polymorphism analysis

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Journal of Forestry research 2017年第4期28卷 653-660页

作者： Shu Diao Yanbo Wang Changjun Ding Yingying Chang Lixiong Liang Yanan Gao Bingyu Zhang Xiaohua Su State Key Laboratory of Tree Genetics and Breeding Research Institute of ForestryChinese Academy of ForestryBeijing 100091People’s Republic of China Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration Research Institute of ForestryChinese Academy of ForestryBeijing 100091People’s Republic of China

DNA methylation, an epigenetic mechanism used by cells to control gene expression, has an important biological role in plant development and environmental fitness. Since plant DNA methylation is closely related to environmental conditions, variation during the day is expected. Here, in genetically identical plants of Populus nigra clone N46, DNA methylation changes in leaves over a 24 h period were detected using the methylation-sensitive amplification polymorphism method. The results showed different DNA methylation patterns in mature poplar leaves: not only in individuals at the same time, but also in samples at each of the six time during the day. In addition, night samples had a higher percentage of methylation than in morning samples. However, no statistically significant differences were found among the samples gathered at different times. Similar results were obtained for three other P. nigra clones with different genetic backgrounds. Real time qPCR showed that the DNA methyltransferase genes Pt-MET1 and Pt-SOM1 involved in CG DNA methylation in poplar were stable over a 24 h period in leaves of P. nigra N46 compared with circadian-controlled genes. That could be part of the reason that methylation of CCGG sites is stable in those leaves. That DNA methylation differed even in genetically identical plants indicates the specificity of DNA methylation changes in their genomes. No statistically significant differences in methylation changes were found between day and night, suggesting that DNA methylation is more stable than expected and is unlikely to be involved in circadian regulation in plants.

关键词： Cytosine methylation Epigenetic Populus nigra Methylation-sensitive amplification polymorphism (MSAP) Variation

Impacts of seismic activity and climatic change on Chinese history in the recent millennium

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Journal of Geographical Sciences 2022年第11期32卷 2328-2348页

作者： FAN Jiawei JIANG Hanchao XU Hongyan ZHANG Wei State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing 100029China Xinjiang Pamir Intracontinental Subduction national Observation and research Station Beijing 100029China Urumqi institute of Central Asia Earthquake China Earthquake AdministrationUrumqi 830011China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsCASBeijing 100029China

General history of disasters in China suggests that China has frequently experienced two major natural disasters in its long history,one is from catastrophic earthquake events,and the other is from extreme climatic events,due to its unique active tectonic environment and climatic *** these two major natural disasters have caused great damage to human society,it remains unclear whether and how they affect Chinese dynasty alternation on decadal(emperor)*** on detailed comparisons between abrupt climatic changes,catastrophic seismic activities,and the history of Chinese dynasty alternation from 1000–2000 AD,we conclude that on decadal timescales,extreme drought(and/or flood)events could indeed significantly reduce agricultural production,cause severe food shortages and famine,and result in increases in population exile,rising food prices and inflation,and insufficient supplies for military defense,which could exceed social resilience and eventually lead to financial risks and social upheavals of the *** addition,catastrophic seismic events in the densely populated,agricultural areas of China,including the 1303 surface wave magnitude(M_(s))8.0 Hongtong earthquake,the 1556 M_(s)8.25Huaxian earthquake and the 1920 M_(s)8.5 Haiyuan earthquake,caused more than 200,000casualties and millions of victims to live in exile which was almost equivalent to the order of magnitude of those extreme climatic events-induced *** secondary geological hazards related to the earthquakes(e.g.,extensive landslides and soil erosion),which could last for decades,caused more casualties and reduced food ***,great plague spread caused by the casualties could significantly increase psychological panic among the survivors,resulting in social ***,catastrophic seismic events could also accelerate the collapse of the dynasties(e.g.,the Ming dynasty)without immediate mitigation *** study indicates that catastro

关键词： catastrophic seismic activity extreme climatic event agricultural production social stability Chinese dynasty alternation

Population divergence of aggregation pheromone responses in Ips subelongatus in northeastern China

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Insect Science 2016年第5期23卷 728-738页

作者： Da-Feng Chen Ye-Jing Li Qing-He Zhang Su-Fang Zhang Hong-Bin Wang Zhen Zhang Li-Lin Zhao Xiang-Bo Kong Key Laboratory of Forest Protection of State Forestry Administration Research Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry Beijing China State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences Beijing China Sterling International Inc. Spokane Washington USA

The Asian larch bark beetle, Ips subelongatus, is considered to be the major pest of larch within its natural range. We investigated the electrophysiological and behavioral characteristics as well as mitochondrial DNA cytochrome oxidase subunit I sequences of L subelongatus from 13 geographic populations throughout northeastern China in order to explore population divergence of aggregation pheromone responses and the extent of potential genetic divergence. Electrophysiological analyses showed that antennae of I. sube-longatus from all the six tested populations responded strongly to （S）-（-）-ipsenol （100% detection; 0.35-0.73 mV） in gas chromatography （GC）-electroantennographic detection （EAD） analyses, while its antipode, （R）-（＋）-ipsenol was antennally inactive. I. subelon- gatus populations varied in their responses to （R）-（-）- and （S）-（＋）-ipsdienol in GC-EAD analyses. Behavioral bioassays demonstrated that （S）-（-）-ipsenol alone was significantly attractive at all the tested sites, supporting its status as a key pheromone component of L subelongatus, whereas （S）-（＋）-ipsdienol was inactive alone. Adding （S）-（＋）-ipsdienol to （S）-（-）-ipsenol did not have any effect on the trap catches from some populations in Inner Mongolia. However, （S）-（＋）-ipsdienol showed a strong synergistic effect on （S）-（-）- ipsenol from several populations in Jilin and Liaoning Provinces, and a weak synergistic effect from some transition populations in Heilongjiang Province. Furthermore, 27 mito- chondrial haplotypes were found among the 13 populations （intraspecific nucleotide di- vergence, 0.1%-1.1%）. Analyses of molecular variance and haplotype networks indicated that different geographic populations have developed some genetic variation but did not form completely independent groups. From an applied point of view, a universal synthetic binary blend ofracemic ipsenol and （S）-（＋）-ipsdienol might have a potential for monitoring or even mass-trapping of I. subelongatus across northeastern Chin

关键词： aggregation pheromone GC-EAD field trapping Ips subelongatus mtDNA-COI population divergence

Excessive ammonia inhibited transcription of MsU2 gene and furthermore affected accumulation distribution of allantoin and amino acids in alfalfa Medicago sativa

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Journal of Integrative Agriculture 2015年第7期14卷 1269-1282页

作者： WANG Li JIANG Lin-lin Nomura Mika Tajima Shigeyuki CHENG Xian-guo College of Life Science Shanxi Normal University Key Laboratory of Plant Nutrition and Fertilizers Agriculture of Ministry/Insititute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences Faculty of Agriculture Kagawa University 2393 Ikenobe Miki-choKita-gun Kagawa 761-0795 Japan

In legume plants, uricase gene （Nodulin-35） plays a positive role in metabolism of ureide and amide compounds in symbiotic nitrogen-fixing in the nodules. In this study, a pot experiment was performed to examine the effects of ammonium application on the transcription of MsU2 gene and distribution of major nitrogen compounds in alfalfa Medicago sativa. Data showed that alfalfa plant has a significant difference in contents of nitrogen compounds in xylem saps compared with soybean plant, and belongs to typical amide type legume plants with little ureide accumulation, and the accumulation of asparagines and ureide in the tissues of alfalfa is mainly gathered in the nodules. Northern blotting showed that excessive ammonium significantly inhibited the transcription of MsU2 gene in the nodules and roots, and mRNA accumulation of MsU2 gene in the plants exposed to excessive ammonium decreased gradually with culture time extension, indicating that application of ammonium significantly inhibited the transcription of MsU2 gene in the alfalfa plants. Although the application of exces- sive ammonium increased the contents of amino acids in various tissues of alfalfa, the accumulation of allantoin reflecting the strength of uricase activity is remarkably reduced in the xylem saps, stems and nodules when alfalfa plants exposed to excessive ammonium, suggesting that application of excessive ammonium generated a negative effect on symbiosis fixing-nitrogen system due to inhibition of ammonium ion on uricase activity in the nodules of alfalfa. This result seems to imply that application of excessive ammonium in legume plants should not be proposed to avoid affecting the ability of fixing nitrogen in the nodules of legume plants, and reasonable dose of ammonium should be recommended to effectively utilize the fixed N from atmosphere in legume plant production.

关键词： alfalfa amino acids ammonium MsU2 gene allantoin

Temporal variations of reference evapotranspiration and its sensitivity to meteorological factors in Heihe River Basin, China

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Water Science and Engineering 2015年第1期8卷 1-8页

作者： Jie Zhao Zong-xue Xu De-peng Zuo Xu-ming Wang College of Water Sciences Beijing Normal University

On the basis of daily meteorological data from 15 meteorological stations in the Heihe River Basin （HRB） during the period from 1959 to 2012, long-term trends of reference evapotranspiration （ET0） and key meteorological factors that affect ET0 were analyzed using the Mann- Kendall test. The evaporation paradox was also investigated at 15 meteorological stations. In order to explore the contribution of key meteo- rological factors to the temporal variation of ET0, a sensitivity coefficient method was employed in this study. The results show that：（1） mean annual air temperature significantly increased at all 15 meteorological stations, while the mean annual ET0 decreased at most of sites; （2） the evaporation paradox did exist in the HRB, while the evaporation paradox was not continuous in space and time; and （3） relative humidity was the most sensitive meteorological factor with regard to the temporal variation of ET0 in the HRB, followed by wind speed, air temperature, and solar radiation. Air temperature and solar radiation contributed most to the temporal variation of ETo in the upper reaches; solar radiation and wind speed were the determining factors for the temporal variation of ET0 in the middle-lower reaches.

关键词： Reference evapotranspiration Evaporation paradox Meteorological factor Heihe River Basin

Imposing Active Sources during High-Frequency Passive Surface-Wave Measurement

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Engineering 2018年第5期4卷 685-693页

作者： Feng Cheng Jianghai Xia Chao Shen Yue Hu Zongbo Xu Binbin Mi Subsurface Imaging and Sensing Laboratory Institute of Geophysics and Geomatics China University of Geosciences Wuhan 430074 China School of Earth Sciences Zhejiang University Hangzhou 310027 China School of Measurement and Testing Engineering China Jiliang University Hangzhou 310018 China Department of Geosciences Boise State University Boise ID 83725 USA

Passive surface-wave utilization has been intensively studied as a means of compensating for the short-age of low-frequency information in active surface-wave measurement, In general, passive surface-wave methods cannot provide phase velocities up to several tens of hertz; thus, active surface-wave methods are often required in order to increase the frequency range, To reduce the amount of field work, we pro-pose a strategy for a high-frequency passive surface-wave survey that imposes active sources during con-tinuous passive surface-wave observation; we call our strategy ＂mixed-source surface-wave （MSW） measurement,＂ Short-duration （within 10 min） passive surface waves and mixed-source surface waves were recorded at three sites with different noise levels： namely, inside a school, along a road, and along a railway, Spectral analysis indicates that the high-frequency energy is improved by imposing active sources during continuous passive surface-wave observation, The spatial autocorrelation （SPAC） method and the multichannel analysis of passive surface waves （MAPS） method based on cross-correlations were performed on the recorded time sequences, The results demonstrate the flexibility and applicability of the proposed method for high-frequency phase velocity analysis, We suggest that it will be constructive to perform MSW measurement in a seismic investigation, rather than exclusively performing either active surface-wave measurement or passive surface-wave measurement,

关键词： Passive surface wave Active surface wave High frequency Mixed-source surface wave Spatial autocorrelation Multichannel analysis of passive surface waves