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Checklist and Zoogeographical Region Analysis of Hawkmoths(Lepidoptera:Sphingidae)in the Guokui Mountain,Heilongjiang Province
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作者 Zhao Jiaqi Zhang Jiake Xie Tongyin 《Journal of Northeast Agricultural University(English Edition)》 2025年第2期10-22,共13页
This paper conducted a systematic survey and zoogeographical region analysis of the family Sphingidae in the Guokui Mountain,Heilongjiang Province.Collections were made from May 2023 to August 2024 using the light-tra... This paper conducted a systematic survey and zoogeographical region analysis of the family Sphingidae in the Guokui Mountain,Heilongjiang Province.Collections were made from May 2023 to August 2024 using the light-trap method.A total of 14 species and 11 subspecies from 18 genera and three subfamilies were recorded.One species(Ambulyx tobii)and two subspecies(Ambulyx japonica koreana and Clanis undulosa undulosa)were new records for Heilongjiang Province.The study showed that the subfamily Smerinthinae had the most species(subspecies),while the subfamily Sphinginae had the fewest.Among the world's zoogeographical region,most species(subspecies)in the Guokui Mountain belonged to the palearctic region,with eight species and seven subspecies were also found in the oriental region.This indicated a close biogeographic connection between the two regions.Among the Chinese zoogeographical regions,the northeastern territory,northern territory and northwestern territory had the most abundant species(subspecies).It was also found that the distribution pattern types of hawkmoths in the Guokui Mountain were diverse,with the'northeastern territory-northern territory-northwestern territory'and'northeastern territory-northern territorynorthwestern territory-western plateau-southwestern territory-central territory-southeastern territory'types having the most species(subspecies).In addition,the Guokui Mountain hawkmoths were mostly distributed interregionally.The distribution patterns that contained the northeastern territory were the most numerous,followed by the northern territory.The rich diversity of the family Sphingidae in the Guokui Mountain was closely related to the unique climate,environment and vegetation types in the area.The results could help to improve the biodiversity database of Heilongjiang Province and researches on hawkmoths. 展开更多
关键词 SPHINGIDAE zoogeographical region diversity LIGHT-TRAP the Guokui mountain
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Statistical Downscaling Retrieval of Land Surface Temperature in an Area with Complex Landforms in the Eastern Qinling Mountains of China Based on Sentinel-2/3 Satellite Data
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作者 Yuan Yuan Zheng Wei +2 位作者 Zhao Shi-fa Meng Ming-xia Hu Juan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2023年第3期60-68,共9页
The study of land surface temperature(LST)is of great significance for ecosystem monitoring and ecological environmental protection in the Qinling Mountains of China.In view of the contradicting spatial and temporal r... The study of land surface temperature(LST)is of great significance for ecosystem monitoring and ecological environmental protection in the Qinling Mountains of China.In view of the contradicting spatial and temporal resolutions in extracting LST from satellite remote sensing(RS)data,the areas with complex landforms of the Eastern Qinling Mountains were selected as the research targets to establish the correlation between the normalized difference vegetation index(NDVI)and LST.Detailed information on the surface features and temporal changes in the land surface was provided by Sentinel-2 and Sentinel-3,respectively.Based on the statistically downscaling method,the spatial scale could be decreased from 1000 m to 10 m,and LST with a Sentinel-3 temporal resolution and a 10 m spatial resolution could be retrieved.Comparing the 1 km resolution Sentinel-3 LST with the downscaling results,the 10 m LST downscaling data could accurately reflect the spatial distribution of the thermal characteristics of the original LST image.Moreover,the surface temperature data with a 10 m high spatial resolution had clear texture and obvious geomorphic features that could depict the detailed information of the ground features.The results showed that the average error was 5 K on April 16,2019 and 2.6 K on July 15,2019.The smaller error values indicated the higher vegetation coverage of summer downscaling result with the highest level on July 15. 展开更多
关键词 Eastern Qinling mountains Sentinel-2/3 land surface temperature statistical downscaling
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Trial mountain climbing algorithm for solving the inverse kinematics of redundant manipulator 被引量:3
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作者 周友行 何清华 邓伯禄 《Journal of Central South University of Technology》 2002年第4期285-288,共4页
Trial mountain climbing algorithm to solve the inverse kinematics problem of redundant manipulator is introduced, and a method of describing a numeral with a special numeration system is given to define the changed st... Trial mountain climbing algorithm to solve the inverse kinematics problem of redundant manipulator is introduced, and a method of describing a numeral with a special numeration system is given to define the changed step of the trail mountain climbing algorithm. The results show that a likelihood solution can be found quickly in the infinite groups of likelihood solutions within the limited search times, and need not calculate the anti trigonometric function and the inverse matrix. In addition, this algorithm has many good qualities such as concise algorithm, tiny computation, fast convergence velocity, good stability and extensive adaptability. 展开更多
关键词 MANIPULATOR tunnel-drilling robot KINEMATICS equation TRIAL mountain CLIMBING ALgoRitHM
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Ediacarian Volcanic Rocks and Basic Dikes from the Lac Ifni Sector of the Central High Atlas Mountains:Petrographic Studies and Clinopyroxene Chemical Composition
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作者 Sad Belkacim M.Ikenne +3 位作者 S.Arai H.Gahlan A Ahmed Hassan Y.Ishida 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期198-198,共1页
The Ediacarian volcanic series from the Lac Ifni sector are composed of a large variety of rocks from basalts and rhyolites to intermediates facies such as andesites,rhyodacites and pyroclastites.All these rocks are i... The Ediacarian volcanic series from the Lac Ifni sector are composed of a large variety of rocks from basalts and rhyolites to intermediates facies such as andesites,rhyodacites and pyroclastites.All these rocks are intruded by dolerite dikes.Secondary processes are reflected by total serpentinization of olivine within basic andesite and by albitization 展开更多
关键词 High ATLAS mountainS Anti ATLAS mountainS volcanism Ediacarian CLINOPYROXENE ICP-MS Laser OROGENIC calc-alcaline THOLEIitIC
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Evaluation and reasonable exploitation on the natural view resources of Lushan Mountain scenic spot
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作者 HU Haihui FAN Jinping ZHUO Lihuan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2007年第1期49-52,共4页
The paper carried on the classified and rating evaluation primarily on natural landscape resources in Lushan Mountain. According to the evaluation, exploiting and utilizing the situation of scenic spot natural landsca... The paper carried on the classified and rating evaluation primarily on natural landscape resources in Lushan Mountain. According to the evaluation, exploiting and utilizing the situation of scenic spot natural landscape resources, some reasonable advices were given on further exploiting Lushan Mountain natural scenic spot, expecting that it could supply some theoretical references for the natural landscape resources sustainable development in Lushan Mountain in the future. 展开更多
关键词 natural landscape resources evaluation of hierarchical classification developing suggestions Lushan mountain
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Outdoor thermal environmental research of the mountainous city by GIS
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作者 卢军 陈金花 +1 位作者 高亚锋 陈静 《Journal of Central South University of Technology》 EI 2006年第3期225-228,共4页
The study of urban outdoor thermal environment was carried out in one of the mountainous cities by using geography information system(GIS) technique which is connected with predicting and evaluating models for the out... The study of urban outdoor thermal environment was carried out in one of the mountainous cities by using geography information system(GIS) technique which is connected with predicting and evaluating models for the outdoor thermal environment, monitoring data and simulating data. A prediction and evaluation system were set up. A typical mountainous city, i.e., Yunyang city in Chongqing in China, was taken as an example, its urbanization trend and population growth was predicted and evaluated. The heat island intensity and its trend were simulated, the temperature field, velocity field and the humidity field were analyzed. The results show that GIS is an effective tool to deal with the outdoor thermal environment, especially for the mountainous cities with special geographical particularities. GIS can be used in the environmental management and the city planning especially for the mountainous cities. 展开更多
关键词 outdoor thermal environment GIS heat island mountainous city
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Effects of Soil Characters on the Tea Quality in the Tea Region of Qin-Ba Mountain,Hubei Province,PR China 被引量:1
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作者 Yu-Qiong Chen Xie-Shu Wang +3 位作者 Cheng-Jun Guo Jin Huang Zhi Yu De-Jiang Ni 《茶叶》 2013年第4期212-219,共8页
Based on the analysis of physical and chemical properties of soil,nutrient elements and biochemical compositions of tea leaves,the relationship between soil characters and tea quality was studied.The results showed th... Based on the analysis of physical and chemical properties of soil,nutrient elements and biochemical compositions of tea leaves,the relationship between soil characters and tea quality was studied.The results showed that soil total phosphorus,potassium,available potassium,copper and zinc were the main factors which affected and limited the content of nutrient elements of tea leaves.Furthermore,soil pH,organic matter,total nitrogen,potassium,exchangeable calcium,magnesium,available copper and zinc were the main factors affecting and limiting the content of biochemical compositions in tea leaves.Tea quality could be improved by controlling these soil factors. 展开更多
关键词 茶叶品质 土壤特性 秦巴山区 湖北省 营养元素含量 茶区 中国 生化成分
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Practice-based Research on Popularity of Tea Culture in Northern Mountainous Area and Improvement of Students' Humanism Spirit
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作者 Zhao YH Han YY +3 位作者 Shang AQ Zhang XM Wen J Song YS 《茶叶》 2013年第4期507-514,共8页
In this paper,questionnaires about college tea culture and humanism spirit have been investigated in the undergraduates of Hebei Agricultural University in mountainous area of Northern China.After analyzing the survey... In this paper,questionnaires about college tea culture and humanism spirit have been investigated in the undergraduates of Hebei Agricultural University in mountainous area of Northern China.After analyzing the survey results and the causes,the author made references and gave recommendations to the university students about the tea culture and humanism spirit cultivation. 展开更多
关键词 人文精神 茶文化 大学生 北部山区 基础 人气 河北农业大学 北方山区
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R^(3)上具有一般凹凸非线性项的Klein-Gordon-Born-Infeld方程无穷多解的存在性
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作者 陈尚杰 《数学物理学报(A辑)》 CSCD 北大核心 2024年第3期637-649,共13页
该文运用临界点理论中的Z_(2)-山路定理得到了R^(3)上具有凹凸非线性项的Klein-Gordon方程和Born-Infeld理论耦合系统无穷多解的存在性.
关键词 KLEIN-goRDon方程 Born-Infeld理论 变分方法 Z_(2)-山路定理
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MINERALIZATION AGES OF GOLD-HYDROTHERMAL DEPOSITS IN NORTHERN ZONE OF EASTERN KUNLUN MOUNTAINS BASED ON FISSION TRACK ANALYSIS
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作者 Yuan Wanming 1,Wang Shicheng 1,Mo Xuanxue 2,Wang Lanfen 1 2 China University of Geosciences, Beijing 100083,China) 《地学前缘》 EI CAS CSCD 2000年第S1期329-330,共2页
The age of mineralization in a mining area is a primary factor in various researches related to ore\|forming process. It is that the uncertainty of mineralization ages of gold ore deposits in northern zone of eastern ... The age of mineralization in a mining area is a primary factor in various researches related to ore\|forming process. It is that the uncertainty of mineralization ages of gold ore deposits in northern zone of eastern Kunlun Mountains, Qinghai Province, restrains to probe the relationship of the deposits to the regional tectonic evolution. This paper documents the fission track method used to determine the ages of gold ore deposits in eastern Kunlun Mountains and considers the implication for the origin of the deposits.Eastern Kunlun Mountains is the northern part of the Qinghai—Tibet Plateau and is of three deep\|seated fault belts in about EW extension. This work mainly includes three gold ore districts. All of them, in the north of Mid\|Kunlun fault belt, belong to northern part of eastern Kunlun Mountains. The Yanjingou district, with geographical coordinate 96°00’E and 36°10’N, is located 60 km north of Hongqigou district . Both of them are large, typical tectonoalteration gold deposits and were formed in similar geological setting. Hongshuihe ore district is located 50 km east of Yanjingou district and includes tectonoalteration and magmatic cryptoexplosive gold deposits. Outcroped strata are dominantly Jinshuikou Group metamorphic rocks of Lower Proterozoic erathem. The occurrence area of igneous rocks, especially granitoid, accounts for about 90% in first two districts and become less in Hongshuihe district. The gold deposits occur in NW\|striking fault belts. The Rb\|Sr isochron age and K\|Ar isotopic age of Moyite relevant to the gold mineralization are respectively 228 25Ma and 207 1Ma. Rb\|Sr dating of diorite porphyrite is 209 09Ma. Sericite selected from Yanjingou orebody has 252 9Ma K\|Ar age. The ore in Hongqigou district has 197Ma K\|Ar age and 210Ma model age of Pb isotope of galena. 展开更多
关键词 mineralization age thermal event fission track thermochron ology fission track analysis eastern Kunlun mountains
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G1-CRITIC-VIKOR模型在山区干线公路交通安全评价中的应用研究
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作者 王立 李智俣 +3 位作者 何瑞春 王治利 徐重岐 赵冬 《安全与环境学报》 北大核心 2025年第5期1666-1674,共9页
为克服单一赋权法的局限性,结合山区干线公路交通特征及交通安全评价指标的选取原则,从社会因素、驾驶因素、环境因素、管理因素和道路因素五个维度出发,选取18个综合评价指标,运用序关系分析法(Order Relation Analysis Method,G1)-指... 为克服单一赋权法的局限性,结合山区干线公路交通特征及交通安全评价指标的选取原则,从社会因素、驾驶因素、环境因素、管理因素和道路因素五个维度出发,选取18个综合评价指标,运用序关系分析法(Order Relation Analysis Method,G1)-指标相关性权重确定法(Criteria Importance Through Intercriteria Correlation,CRITIC)确定各评价指标的权重,并结合折中妥协多属性决策法(VlseKriterijumska Optimizacija I Kompromisno Resenje,VIKOR)对山区干线公路交通安全进行综合评价,提出了基于G1-CRITIC-VIKOR模型的山区干线公路交通安全综合评价及比选方法。以中国西部6条山区干线公路为例进行实证研究,结果表明,G1-CRITIC-VIKOR模型的评价效果与传统的秩和比(Rank-Sum Ratio,RSR)综合评价法及加权逼近理想解排序法(Technique for Order Preference by Similarity to Ideal Solution,TOPSIS)的评价结果基本一致,且评价效果明显优于后者,具有更好的辨识性,验证了该模型的可行性和科学性。 展开更多
关键词 安全工程 交通安全评价 山区干线公路 组合赋权 秩和比法 加权逼近理想解排序法
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Design philosophy and “Feng Gu”of landscape architecture in mountainous regions 被引量:1
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作者 Chunlan Du Tingting Fu +3 位作者 Xin Luo Bo Li Jin Zou Chang Li 《西部人居环境学刊》 2015年第A01期59-64,共6页
关键词 mountainous environment Landscape character Design method Adaptive component architecture
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SIGNIFICANCE AND CHARACTERISTICS OF OPHIOLITE SUITE IN LAJI SHAN, SOUTHERN QILIAN MOUNTAINS, QINGHAI PROVINCE,CHINA
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作者 Yang Weiran,Deng Qinglu,Wu Xiulin (China University of Geosciences,Wuhan 430074,China) 《地学前缘》 EI CAS CSCD 2000年第S1期130-131,共2页
Laji Shan is located in the eastern part of Qinghai Province,sandwiched between Xining and Hualong Basins.It is about 250km long and 10~20km wide from Riyueshan in the west to Minheguanting in the east.Laji Shan belo... Laji Shan is located in the eastern part of Qinghai Province,sandwiched between Xining and Hualong Basins.It is about 250km long and 10~20km wide from Riyueshan in the west to Minheguanting in the east.Laji Shan belongs to the Caledonian orogenic belt.Its basement consists of the rocks of Palaeo\|Protero zoic Hualong Group (Pt 1 hl ) and Neo\|Proterozoic Huangzhong Group (Pt\-3 h ).There are ptygmatic folds,closely linear type folds,strongly structural d ifferentiation and schistosity developed,suggesting that the basement underwent deep seated ductile deformation.The main part of Laji Shan is composed of Early\|Palaeozoic marine facies volcanic rocks and clastic sedimentary rocks,and suffered greenschist facies metamorphism and brittle\|ductile deformation.Others are composed of Ea rly\|Palaeozoic basic and ultrabasic rocks,intermediate\|acidic intruded rocks a nd dike rocks.Devonian molasse formation in Laji Shan is in uncomfortable contac t with underlying strata.Jurassic and Cretaceous systems are intermont basin dep osits,corresponding to a cover. 展开更多
关键词 OPHIOLitE SUitE Qinghai—Xizang PLATEAU QILIAN mountains Laji Shan
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Limiting drainage criterion for groundwater of mountain tunnel 被引量:1
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作者 程盼 赵炼恒 +2 位作者 李亮 邹金锋 罗伟 《Journal of Central South University》 SCIE EI CAS 2014年第12期4660-4668,共9页
Large amount of groundwater discharging from tunnel is likely to cause destruction of the ecological environment in the vicinity of the tunnel, thus an appropriate drainage criterion should be established to balance t... Large amount of groundwater discharging from tunnel is likely to cause destruction of the ecological environment in the vicinity of the tunnel, thus an appropriate drainage criterion should be established to balance the tunnel construction and groundwater.To assess the related problems, an limiting drainage standard ranging from 0.5 to 2.0 m3/(m·d) was suggested for mountain tunnels based on survey and comparative analysis. After that, for the purpose of verifying the rationality of the standard, a calculated formula for dewatering funnel volume caused by drainage was deduced on the basis of the groundwater dynamics and experience method.Furthermore, the equation about the relationship between water discharge and drawdown of groundwater table was presented. The permeability coefficient, specific yield and groundwater table value were introduced, and then combined with the above equation, the drawdown of groundwater table under the proposed limiting drainage criterion was calculated. It is shown that the proposed drainage standard can reach the purpose of protecting ecological environment under the following two conditions. One is the permeability coefficient ranges from 10-4 to 10-5 m/s and the specific yield ranges from 0.1 to 0.001. The other is the permeability coefficient varies from 10-6 to 10-8 m/s and the specific yield varies from 0.1 to 0.01. In addition, a majority of common geotechnical layers are involved in the above ranges. Thus, the proposed limiting drainage standard which ranges from 0.5 to 2.0 m3/(m·d) for mountain tunnel is reasonable. 展开更多
关键词 mountain tunnel groundwater dewatering funnel limiting drainage criterion drawdown of groundwater table
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THE CLIMATIC STUDY OF CHANGBAI MOUNTAIN BY INTEGRATION OF REMOTE SENSING INFORMATION AND GEO-CODED IMAGES
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作者 Yang Meihua Department of Geography, Northeast Normal University Wang Yeqiao Changchun Inst. of Geography, Chinese Academy of Sciences 《遥感信息》 CSCD 1990年第A02期39-40,共2页
Ⅰ. INTRODUCTION Changbai Mountain is situated between E127°54′-128°08′, N40°58′-42°06′ about 2700 meters above sea level. It is the typical area of the mountainous climate in the monsoon area ... Ⅰ. INTRODUCTION Changbai Mountain is situated between E127°54′-128°08′, N40°58′-42°06′ about 2700 meters above sea level. It is the typical area of the mountainous climate in the monsoon area of the temperate zone on the globe. The well reserved primeval vertical distribution of natural landscape belts and the Natural Conservation of Changbai Mountains adopted by the UNESCO′s MAB Program cause the worldwide attention of geographers. Beside the complexity of the climatic structure itself, the mechanical effection of the high mountain body also effect the climate in the eastern part of China. In the mountain area where short of meteorological observation data, the climatic study by remote sensing is favorable for discovery and representation of climatic law in large area. 展开更多
关键词 the CLIMATIC STUDY OF CHANGBAI mountain BY INTEGRATIon OF REMOTE SENSING INFORMATIon AND GEO-CODED IMAGES GEO data body
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A STUDY ON THE SOIL RESPIRATION OF THE FORESTS ON GONGGA MOUNTAIN
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作者 Luo Ji 1, Dong Yunshe 2, Yang Qingwei 1 2.Institute of Geography, Chinese Academy of Sciences, Beijing 100101,China) 《地学前缘》 EI CAS CSCD 2000年第S1期400-400,共1页
CO 2 is the key gas of the greenhouse ones, the effect of its radiation on temperature ascent is 60% of the total greenhouse gases. The elevating CO 2 concentration influences to a great extent the future climate wa... CO 2 is the key gas of the greenhouse ones, the effect of its radiation on temperature ascent is 60% of the total greenhouse gases. The elevating CO 2 concentration influences to a great extent the future climate warming in a regional or global scale. Forest is the main part of carbon cycling in the land ecosystem.. Monitoring CO 2 absorption and emission in the forest ecosystem play a non\| fungible role in study on the global change. Gongga Mountain is located in the southeast margin of the Tibetan Plateau, and there exist intact vertical vegetation zonality, which is advantageous for measuring soil CO\-2 emission on each vertical forest zonality and researching the ecological factors of soil respiration.The east slope of Gongga Mountain develops 5 natural forest vertical zones from lower to higher altitudes: secondary forest, ever\|greened and deciduous broad\|leaved mixed forest, broad\|leaved and coniferous mixed forest, coniferous forest and alpine shrubs. Based on the two\|year’s measurement, the soil respiration of each forest averaged: 5 488, 6 344, 5 912, 4 176 and 3 864μmol CO 2/(m 2·s); the flux of soil CO 2 emission was arranged: 208 628, 241 169, 224 746, 158 752 and 146 891kg CO 2/(hm 2·d), respectively. 展开更多
关键词 gongga mountain forest soil respiration CO 2 emission
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THE GLOBAL TECTONIC SYSTEMS AND A LATITUDINAL MOUNTAIN-PLATEAU CHAIN ON THE NORTH HEMISPHERE
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作者 Ma Zongjin(Institute of Geology,China Seismological Bureau,Beijing 100029,China) 《地学前缘》 EI CAS CSCD 2000年第S1期344-345,共2页
Three global tectonic systems that formed since the middle Jurassic (160Ma ago)are outlined based on the global map of the Cenozoic and Mesozoic tectonics edited by Ma Zongjin et al.(1996).They are the circum\|Pacific... Three global tectonic systems that formed since the middle Jurassic (160Ma ago)are outlined based on the global map of the Cenozoic and Mesozoic tectonics edited by Ma Zongjin et al.(1996).They are the circum\|Pacific tectonic system,the mid\|ocean ridge tectonic system and the intra\|continental tectonic system of the north hemisphere.The map shows that about 80% of the total length of the continental orogens are concentrate on the north hemisphere of the earth,of which a latitudinal mountain\|plateau chain occur within a zone between north latitude 20°and 50°.Seismic and volcanic activities demonstrate that the intracontinental tectonic system on the north hemisphere is still active.Whilst distribution of the continental deep\|focus earthquakes and almost ultra high\|pressure rock found so far over the World,that are assumed both related to recent or previous deep subduction of continent,along with this zone.The latitudinal mountain\|plateau chain is subdivided into four active tectonic region of Qinghai—Xizang(Tibet),Iranian,eastern mediterranean and North American,both characterized by an individual similar mountain\|plateau\|basin structure with major active boundaries or controlling faults (Fig.1).These active regions are all close to primary dynamic boundaries of continent\|continent collision.Solution of source mechanisms shows that regional tectonic stress field in these regions are dominated by a nearly NS or NNE—SSW direction compression corresponding to a local plate motions and a global compressive zone.Correlation between the formation of the continental latitudinal mountain\|plateau chain on north hemisphere and the oceanic plate tectonics is discussed using the information of the “Map of Magnetic Lineations of the World’s Ocean Basins (Cande et al.,1989)”and the Cenozoic and Mesozoic tectonic evolution in the continents.Total 49 accretion units formed during 6 accretion stages of the ocean spreading in three chief oceans (the Pacific,the India and the Atlantic)si nce 160Ma ago,are subdivided.The distinguished oceanic accretion tectonics in combination with the geometrical and kinematics data of adjust continental f ragments allowed outline of the development of the continental latitudinal tecto nic zone of north hemisphere.Whilst,two global asymmetrical geodynamic systems of north\|south an east\|west direction,that may be composed of meridional conve ction,latitudinal convection and inertial flow resulting from the variation of the Earth’s rotational velocity,are used to discuss on the two global geodynamic systems in which the intracontinental latitudinal tectonic zone developed. 展开更多
关键词 global asymmetrical system geodynamics mountain\| plateau chain seismotectonic system latitudinal tectonic zone
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Crustal anisotropy of Taihang Mountain Range using azimuthal variation of receiver functions 被引量:6
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作者 田宝峰 李娟 姚振兴 《地震学报》 CSCD 北大核心 2008年第4期355-366,441,共12页
摘要探讨了利用接收函数方位变化研究各向异性复杂地区速度结构的可能性。详细介绍了具有任意对称轴方向的横向各向同性系统中介质响应的计算过程,并将利用接收函数方位变化研究地壳各向异性的方法应用于华北太行山地区。结果表明,研... 摘要探讨了利用接收函数方位变化研究各向异性复杂地区速度结构的可能性。详细介绍了具有任意对称轴方向的横向各向同性系统中介质响应的计算过程,并将利用接收函数方位变化研究地壳各向异性的方法应用于华北太行山地区。结果表明,研究台站下方地壳具有明显的各向异性特征,其中地表盖层表现为8%-15%的慢轴型各向异性;深部地壳各向异性略小,表现为3%-5%的快轴型各向异性特征,不同台站获得的各向异性对称轴的方向及深度分布不具有明显的一致性,区域构造环境的变化可能是导致地壳各向异性存在的原斟。 展开更多
关键词 接收函数 各向异性 方位变化 太行隆起地区
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秦岭大坪峪川金丝猴(Rhinopithecus roxellana)种群生存力分析 被引量:2
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作者 王程亮 王晓卫 +2 位作者 赵海涛 任轶 李保国 《生态学报》 CAS CSCD 北大核心 2016年第23期7724-7731,共8页
小种群的保护已成为保护生物学中一个重要的问题,鉴于小种群极易灭绝的特性,寻找制约小种群存活的关键因子,形成快速拯救的措施,是目前对于小种群进行保护十分迫切的任务。根据秦岭大坪峪地区2个川金丝猴(Rhinopithecus roxellana)种群... 小种群的保护已成为保护生物学中一个重要的问题,鉴于小种群极易灭绝的特性,寻找制约小种群存活的关键因子,形成快速拯救的措施,是目前对于小种群进行保护十分迫切的任务。根据秦岭大坪峪地区2个川金丝猴(Rhinopithecus roxellana)种群连续5a的观察数据,参照群体大小、配偶体制、迁移扩散、环境容纳量、死亡率、灾害的发生频率等种群参数,并结合川金丝猴其他种群的研究结果,利用旋涡模型(Vortex 10.0),对猴群未来100a内的数量动态进行了模拟分析。结果表明,在没有个体迁移的情况下,大坪峪种群种群100a间灭绝概率为95.8%和93%;当存在个体迁移和扩散的情况,灭绝概率为2%和0.4%。因此种群间个体迁移是秦岭大坪峪川金丝猴种群数量动态的限制因子。鉴于此,增加川金丝猴大坪峪种群间的个体交流,能够保证本群川金丝猴长期生存所需的遗传多样性。同时,增加秦岭川金丝猴各种群间的个体交流,建立群间的生境走廊对这一世界性濒危物种的长期存活具有重要的现实意义。 展开更多
关键词 秦岭山脉 川金丝猴 种群生存力分析(PVA) 迁移
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Klein-Gordon-Maxwell系统解的存在性和多解性
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作者 陈丽珍 李安然 李刚 《工程数学学报》 CSCD 北大核心 2019年第6期647-657,共11页
Klein-Gordon-Maxwell系统具有很强的物理背景,它提供了带电粒子物质和它所产生的电磁场之间作用的“二元模型”描述.根据这个模型,粒子物质是一个非线性场方程的孤波解,且电磁场的作用是由场方程与麦克斯韦方程耦合的衡量电位描述的.... Klein-Gordon-Maxwell系统具有很强的物理背景,它提供了带电粒子物质和它所产生的电磁场之间作用的“二元模型”描述.根据这个模型,粒子物质是一个非线性场方程的孤波解,且电磁场的作用是由场方程与麦克斯韦方程耦合的衡量电位描述的.本文利用变分方法和临界点理论研究一类Klein-Gordon-Maxwell系统解的存在性和多重性.首先,利用山路引理,我们证明了系统非平凡解的存在性,其中一个解是非负的,一个解是非正的.其次,运用喷泉定理,文中证明系统在非线性项满足一定条件下无穷多高能量解的存在性.本文所得结果推广了以前的结论. 展开更多
关键词 Klein-gordon-Maxwell系统 山路引理 喷泉定理 高能量解
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