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Interactive effects of elevation and land use on soil bacterial communities in the Tibetan Plateau

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Pedosphere 2020年第6期30卷 817-831页

作者： Yuanyuan YANG Yin zhou zhou SHI Raphael A.VISCARRA ROSSEL Zongzheng LIANG Haizhen WANG lianqing zhou Wu YU College of Environmental and Resource Sciences Zhejiang UniversityHangzhou 310058China Soil and Landscape Science School of Molecular and Life SciencesCurtin UniversityGPO Box U1987Perth WA 6845Australia College of Resource and Environment Tibet UniversityNyingchi 860000China

The Tibetan Plateau of China is uniquely vulnerable to the global climate change and anthropogenic *** soil bacteria exert a considerable influence on the ecosystem function,understanding their response to different climates and land-use types is ***,we characterized the bacterial community composition and diversity across three major ecosystems(cropland,forest,and grassland)in the Sygera Mountains of Tibet,along a typical elevational gradient(3300–4600 m).The abundance of taxa that preferentially inhabit neutral or weak alkaline soil environments(such as Actinobacteria,Thermoleophilia,and some non-acidophilus Acidobacteria)was significantly greater in the cropland than in the forest and ***,the diversity of soil bacterial communities was also significantly greater in the cropland than in the forest and *** observed a unimodal distribution of bacterial species diversity along the elevation *** dominant phyla Acidobacteria and Proteobacteria exhibited consistent elevational distribution patterns that mirrored the abundance of their most abundant classes,while different patterns were observed for Acidobacteria and Proteobacteria at the class *** pH was the primary edaphic property that regulated bacterial community composition across the different land-use ***,soil pH was the main factor distinguishing bacterial communities in managed soils(i.e.,cropland)from the communities in the natural environments(i.e.,forest and grassland).In conclusion,land use(particularly anthropogenic disturbances such as cropping)largely controlled soil environment,played a major role in driving bacterial community composition and distribution,and also surpassed climate in affecting bacterial community distribution.

关键词： alpine ecosystem climate environmental controls pyrosequencing soil microbe

Machine learning-based automatic construction of earthquake catalog for reservoir areas in multiple river basins of Guizhou province,China

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Earthquake Science 2023年第2期36卷 132-146页

作者： Longfei Duan Cuiping Zhao Xingzhong Du lianqing zhou Institute of Earthquake Forecasting China Earthquake AdministrationBeijing 100036China PowerChina Guiyang Engineering Corporation Limited Guiyang 550081China

Large reservoirs have the risk of reservoir induced *** detecting and locating microseismic events are crucial when studying reservoir *** earthquake monitoring in reservoir areas is one of the effective measures for earthquake disaster prevention and *** this study,we first applied the automatic location workflow(named LOCFLOW)to process 14-day continuous waveform data from several reservoir areas in different river basins of Guizhou *** with the manual seismic catalog,the recall rate of seismic event detection using the workflow was 83.9%.Of the detected earthquakes,88.9%had an onset time difference below 1 s,81.8%has a deviation in epicenter location within 5 km,and 77.8%had a focal depth difference of less than 5 km,indicating that the workflow has good generalization capacity in reservoir *** further applied the workflow to retrospectively process continuous waveform data recorded from 2020 to the first half of 2021 in reservoir areas in multiple river basins of western Guizhou province and identified five times the number of seismic events obtained through manual *** with manual processing of seismic catalog,the completeness magnitude had decreased from 1.3 to 0.8,and a b-value of 1.25 was calculated for seismicity in western Guizhou province,consistent with the b-values obtained for the reservoir area in previous *** results show that seismicity levels were relatively low around large reservoirs that were impounded over 15 years ago,and there is no significant correlation between the seismicity in these areas and reservoir *** patterns were notably different around two large reservoirs that were only impounded about 12 years ago,which may be explained by differences in reservoir storage capacity,the geologic and tectonic settings,hydrogeological characteristics,and active fault the reservoir *** seismicity persisted around two large reservoi

关键词： river basins in Guizhou reservoir earthquake machine learning earthquake location b-value

Temporal and Spatial Images of Ambient Noise Intensity in the Chinese Mainland

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Earthquake Research in China 2017年第3期31卷 289-308页

作者： zhou lianqing Song Xiaodong Zhao Cuiping Key Laboratory of Earthquake Prediction Institute of Earthquake ScienceCEABeijing 100036China University of Illinois at Urbana-Champaign Urbana IL61801USA Institute of Geophysics China Earthquake AdministrationBeijing 100081China

Successive waveforms of the vertical component recorded by 888 broadband seismic stations in the China Seismography Network from January,2010 to June,2011 are used to investigate the temporal and spatial distribution of ambient noise intensity,and the images of ambient noise intensity at the period of 10 s in the Chinese Mainland are obtained. The temporal variation of ambient noise intensity shows some seasonal and periodic characteristics. The maximum ambient noise intensity occurred from January,2011 to March,2011. The spatial distribution images of ambient noise intensity show obvious zoning features,which doesnt correlate with surface geology,suggesting that the noise field is stronger than the site factors. The strength in southeastern coastal areas reaches its maximum and generally decreases toward to inland areas,and arrives at the minimum in the Qinghai-Tibetan Plateau. The zonal intensity distribution is probably correlated with ocean tides from the Philippine Ocean and the Pacific Ocean. It also shows that the influence from the Indian Ocean seems small. However, the ambient noise intensity increases to a certain degree in the Xinjiang area,indicating that the main source of ambient noise in the western area of the Chinese Mainland is not derived from the East and South China Sea,but rather from the deep interior of the Eurasian continent. The ambient noise intensity obtained in this study can supply reference for seismology research based on ambient noise correlation. Moreover,it can supply basic data for attenuation research based on ambient noise, and thus help achieve the object of retrieving the attenuation of Rayleigh waves from ambient noise.

关键词： Ambient noise Noise source Amplitude of surface wave Attenuation

Seismogenic environment and mechanism of the Yangbi M_(S)6.4 earthquake in Yunnan,China

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Earthquake Science 2022年第4期35卷 297-310页

作者： Mengqiao Duan Kezhen Zuo Cuiping Zhao lianqing zhou Institute of Geophysics China Earthquake AdministrationBeijing 100081China Liaoning Earthquake Agency Shenyang 110031China Institute of Earthquake Forecasting China Earthquake AdministrationBeijing 100036China

The Yangbi M_(S)6.4 earthquake occurred on May 21,2021 in western Yunnan,China,where moderate earthquakes strike *** exhibited a typical“foreshock-mainshock-aftershock”sequence and did not occur on a pre-existing active *** seismogenic environment and mechanism of this earthquake have aroused considerable research *** this study,we obtain the three-dimensional v_(P),v_(S)and v_(P)/v_(S)images using the v_(P)/v_(S)consistency-constrained double-difference tomography method,which improves the accuracy of v_(P)/v_(S)*** focus on characteristics of v_(P)/v_(S)images in areas with a lateral resolution of 0.1°,and reveal the seismogenic environment of the Yangbi M_(S)6.4 *** conclusions are as follows:(1)Low velocity and high-v_(P)/v_(S)anomalies are revealed at different depths around the northern segment of the Red River fault.v_(S)and v_(P)/v_(S)images along the Weixi-Qiaohou-Weishan fault and the buried faults on its west show obviously segmented feature.(2)The source region of the Yangbi M_(S)6.4 earthquake is located in a low-v_(P)/v_(S)zone implying high medium ***-v_(P)/v_(S)anomalies in its NW direction indicate cracks development and the existence of fluids or partial melts,which are unfavorable for stress accumulation and triggering large *** conditions have also prevented the earthquake sequence from extending northwestward.(3)With the southeastward extrusion of materials from the Tibetan Plateau,fluid migration was blocked by the low-v_(P)/v_(S)body in the source *** high-v_(P)/v_(S)anomaly beneath the source region may implies that the fluids or partial melts in the middle and lower crust gradually weakened medium strength at the bottom of the seismogenic layer,and preparing the largest foreshock in the transition zone of high to low v_(P)/v_(S).Meanwhile,tectonic stress incessantly accumulated in the brittle upper crust,eventually led to the M_(S)6.4 earthquake occurrence.

关键词： Yangbi M_(S)6.4 earthquake v_(P),v_(S),and v_(P)/v_(S)tomography seismogenic environment and mechanism

Generalization of PhaseNet in Shandong and its application to the Changqing M4.1 earthquake sequence

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Earthquake Science 2023年第3期36卷 212-227页

作者： Zonghui Dai lianqing zhou Xuhui Hu Junhao Qu Xia Li Shandong Earthquake Agency Jinan 250102China Institute of Earthquake Forecasting China Earthquake Administration Beijing 100036China

Waveforms of seismic events,extracted from January 2019 to December 2021 were used to construct a test dataset to investigate the generalizability of PhaseNet in the Shandong *** results show that errors in the picking of seismic phases(P-and Swaves)had a broadly normal distribution,mainly concentrated in the ranges of−0.4–0.3 s and−0.4–0.8 s,*** results were compared with those published in the original PhaseNet article and were found to be approximately 0.2–0.4 s *** had a strong generalizability for P-and S-wave picking for epicentral distances of less than 120 km and 110 km,***,the phase recall rate decreased rapidly when these distances were ***,the generalizability of PhaseNet was essentially unaffected by *** M4.1 earthquake sequence in Changqing,Shandong province,China,that occurred on February 18,2020,was adopted as a case *** detected more than twice the number of earthquakes in the manually obtained *** further verified that PhaseNet has strong generalizability in the Shandong region,and a high-precision earthquake catalog was *** to these precise positioning results,two earthquake sequences occurred in the study area,and the southern cluster may have been triggered by the northern *** focal mechanism solution,regional stress field,and the location results of the northern earthquake sequence indicated that the seismic force of the earthquake was consistent with the regional stress field.

关键词： PhaseNet deep learning generalization Changqing earthquake earthquake catalog

Amplitude and Attenuation From Ambient Noise Correlations

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Amplitude and Attenuation From Ambient Noise Correlations

Measurement of Earthquake Size

2020年中国地球科学联合学术年会

作者： Xiaodong Song lianqing zhou Jiangtao Li Richard Weaver

Ambient noise correlation has been used extensively to retrieve traveltimes of surface waves. However, studies of retrieving amplitude information and attenuation from ambient noise are limited. In this presentation, ... 详细信息

关键词： Amplitude and Attenuation From Ambient Noise Correlations

来源： cnki会议评论

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Earthquake Research in China 2014年第3期28卷 285-298页

作者： Chen Zhangli Chen Hanlin Zhao Cuiping Wang Qincai Hua Wei zhou lianqing China Earthquake Administration Institute of Earthquake Science China Earthquake Administration

The paper begins with a brief review of the research history of earthquake size measurement. On this basis, the author pointed out the following points： ① In recent decades, ML, mb （mH ）, Ms magnitude scales are widely used as measures of earthquake size. However, these magnitude scales have a deficiency of ＂overgeneralization＂ and ＂magnitude saturation＂. Moreover, since they do not fully take into account the regional difference of seismic attenuation, especially the difference of site effects on the amplification of ground motion, these magnitude scales are but inaccurate measures of earthquake size. ② Seismic moment M0 not only has clear physical meaning, but also overcomes the deficiencies existing in ML, mb （mB ） and Ms magnitude scales, so it is the most suitable physical quantity for measuring earthquake size scientifically. In order to continue to use the term ＂magnitude＂, Kanamori defined the moment magnitude scale Act. Although its prerequisite assumptions remain to be studied, it is still a reasonable scale used as a measure of the relative size of an earthquake. ③ For measuring the earthquake size more scientifically, we must make full use of a large amount of waveform data from modern regional digital seismograph networks, strengthen the research on seismic wave attenuation characteristics, site effect, calculation of source parameters and the related scaling relations. In improving the measurement methods for ML, mb （mB ） and Ms magnitude, we should focus on the improvement of Mw scale and carry forward the work as gradually taking Mw magnitude scale as the uniform physical quantity to measure the relative size of earthquakes, so as to lay a more solid foundation for research in earthquake science and earthquake prediction.

关键词： Earthquake Measurement Magnitude Seismic moment Energy Stressdrop

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整体辗钢车轮擦伤焊补可行性研究

中国铁路 2010年第4期 64-66页

作者：周连庆沈阳铁路局总工程师室高级工程师辽宁沈阳110001

车轮是铁道车辆最重要的部件之一,具有承载、导向、传递制动力和牵引力等功能。目前我国铁路数量最多、应用最广的是整体辗钢车轮。当车轮磨耗和擦伤到一定限度就要进行镟修,每次的车削量至少达3mm,相当于车轮运行约30万km,降低了车轮... 详细信息

车轮是铁道车辆最重要的部件之一,具有承载、导向、传递制动力和牵引力等功能。目前我国铁路数量最多、应用最广的是整体辗钢车轮。当车轮磨耗和擦伤到一定限度就要进行镟修,每次的车削量至少达3mm,相当于车轮运行约30万km,降低了车轮使用寿命。通过对整体辗钢车轮焊修可行性的研究,可有效降低维修成本,延长车轮使用寿命,为铁路带来巨大经济效益。

关键词：整体辗钢车轮擦伤焊补可行性

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低年级有效阅读教学策略的实践探索

教育导刊（上半月） 2010年第12期 80-83页

作者：周莲清广州市越秀区教师进修学校广东广州510080

小学低年级作为阅读教学的起始阶段,尤其要抓好＂字、词、句、读、思、练＂等方面的训练,注重阅读兴趣的激发与保持、阅读方法的渗透与归纳。基于＂教学有法,教无定法＂的体认和笔者深入一线课堂的实践与反思,本文着重探讨有效提高低年... 详细信息

小学低年级作为阅读教学的起始阶段,尤其要抓好＂字、词、句、读、思、练＂等方面的训练,注重阅读兴趣的激发与保持、阅读方法的渗透与归纳。基于＂教学有法,教无定法＂的体认和笔者深入一线课堂的实践与反思,本文着重探讨有效提高低年级阅读教学质量的常规性策略。

关键词：阅读教学策略小学低年级实践探索起始阶段阅读兴趣阅读方法教无定法教学质量