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Ecological Regionalization of Suitable Trees, Shrubs and Herbages for Vegetation Restoration in the Farming-Pastoral Zone of Northern China 被引量:5
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作者 康慕谊 董世魁 +3 位作者 黄晓霞 熊敏 陈海 张新时 《Acta Botanica Sinica》 CSCD 2003年第10期1157-1165,共9页
To provide materials for the selection of plant species for vegetation restoration and reconstruction in the farming-pastoral zone in northern China, where the eco-environment has been already deteriorated by over-far... To provide materials for the selection of plant species for vegetation restoration and reconstruction in the farming-pastoral zone in northern China, where the eco-environment has been already deteriorated by over-farming and over-grazing, the suitable trees, shrubs and herbages were examined, screened and identified under the guidance of four principles of taking precedence for ecological conservation, being beneficial to economic production, matching species (trees, shrubs and herbages) with the site, and giving consideration to the integrity of local administrative division. According to the key ecological factors that determine species growth and distribution in the zone, i.e., the lowest daily mean temperature in a year, annual accumulated temperature, and water regimes represented by the moist index, the ratio between annual rainfall and accumulated temperature (>0 degreesC), as well as the soil type influenced by climate, surface substances and landform, the farming-pastoral zone was regionalized into seven parts: ( I) Western Songliao Plain and Da Hinggan Mountain Region; (II) Upper Liaohe River Sandy Region; (III) Mid-Eastern Nei Mongol Plateau and Northwestern Heibei Mountain Region; (IV) Luliang, Taihang and Yanshan Mountain Region; ( V) Ordos Plateau Sandy Region; (VI) Northern Shaanxi to Eastern Gansu Loess Plateau Region; and (VII) Mid Gansu to Eastern Qinghai Plateau Loess Region. And the suitable trees, shrubs and herbages for each region were selected and tabularly introduced in detail. 展开更多
关键词 farming-pastoral zone ecological regionalization suitable species for vegetation restoration northern China
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Timing of the Early Paleozoic Yangtze and Cathysian Convergence: Constraint from U-Pb Geochronology of Hydrothermal Zircons from Mafic Mylonite within the Shoucheng-Piaoli Ductile Shear Zone, Northern Guangxi 被引量:8
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作者 QIN Ya FENG Zuohai +2 位作者 HU Rongguo LI Saisai WANG Chunzeng 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第5期2030-2031,共2页
Objective The northern Guangxi region is in the southwestern part of the Southern China continent,which is located at the junction of the southwest section of the Early Paleozoic Yangtze block and Cathaysian block.A s... Objective The northern Guangxi region is in the southwestern part of the Southern China continent,which is located at the junction of the southwest section of the Early Paleozoic Yangtze block and Cathaysian block.A series of NNE-trending ductile shear zones are developed in this region,and these ductile shear zones are mostly previously suggested boundary faults of the Early Paleozoic Yangtze block and Cathaysian block,such as the Shoucheng–Piaoli ductile shear zone in Northern Guangxi (Meng Yuanku et al., 2016; Zhang Xuefeng et al., 2015). 展开更多
关键词 Pb Th northern Guangxi Timing of the Early Paleozoic Yangtze and Cathysian Convergence Constraint from U-Pb Geochronology of Hydrothermal Zircons from Mafic Mylonite within the Shoucheng-Piaoli Ductile Shear zone
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The Beila Ophiolite from the Bangong-Nujiang Suture Zone, Northern Tibetan Plateau 被引量:2
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作者 ZHAI Qingguo TANG Yue +2 位作者 HU Peiyuan XIAO Xuchang WANG Haitao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期51-,共1页
The Beila ophiolite is located in the middle part of the Bangong-Nujiang suture zone,northern Tibetan plateau.It is a complete ophiolite suite,and plays a key role in understanding the evolution of the Bangong-Nujiang... The Beila ophiolite is located in the middle part of the Bangong-Nujiang suture zone,northern Tibetan plateau.It is a complete ophiolite suite,and plays a key role in understanding the evolution of the Bangong-Nujiang suture zone,as well as the Meso-Tethys Ocean.The Beila ophiolite was composed of peridotite,serpentinite,gabbro,pillow basalt,and minor rodingite.Peridotites comprisemainlymedium–tocoarse–grained serpentinized harzburgites and minor plagioclase-bearing lherzolites and dunites.There are some felsic-ultramafic dykes within the peridotite and they are mainlypegmatoidal pyroxenites,coarse to fine-grained gabbros,and diabases.Gabbros included isotropic and cumulate gabbros,and they commonly contain minor pegmatoidal gabbros veins.Pillow basalts and basaltic andesites overlaid on the margin of the serpentinized peridotites.Rodingite occurs as lenses and/or dykes within the host serpentinized peridotites.Zircon SHRIMP U–Pb dating for two rodingite samples yielded the ages ranging from172 to 164 Ma.Whole-rock geochemical and zircon Hf isotopic data show that the Beila ophiolite shows SSZ-type ophiolite affinity.Finally,we suggest that the Beila ophiolite was generated in an initial subduction process at the middle Jurassic(164–172 Ma). 展开更多
关键词 The Beila Ophiolite from the Bangong-Nujiang Suture zone northern Tibetan Plateau
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Genesis of pyroxenite veins in supra-subduction zone peridotites:Evidence from petrography and mineral composition of Egiingol massif(Northern Mongolia) 被引量:1
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作者 Anas A.Karimov Marina A.Gornova +2 位作者 Vasiliy A.Belyaev Aleksander Ya.Medvedev Nikolay V.Bryanskiy 《China Geology》 2020年第2期299-313,共15页
Swarms of orthopyroxenite and websterite veins are found within Egiingol residual SSZ peridotite massif of Dzhida terrain(Central Asian Orogenic Belt,Northern Mongolia).The process of Egiingol pyroxenite veins formati... Swarms of orthopyroxenite and websterite veins are found within Egiingol residual SSZ peridotite massif of Dzhida terrain(Central Asian Orogenic Belt,Northern Mongolia).The process of Egiingol pyroxenite veins formation is investigated using new major and trace element analyses of pyroxenite minerals,calculations of closure temperatures and composition of equilibrium melt.The pyroxenites show abundant petrographic and geochemical evidence for replacement of the residual peridotite minerals by ortho-and clinopyroxene due to melt-rock interaction.Relics of peridotite olivines are found in pyroxenites,Cr#of spinel increases from peridotites to pyroxenites,and compositions of ortho-and clinopyroxene change from peridotite to pyroxenite.The authors show that calculated equilibrium melts for investigated pyroxenites are very similar to compositions of boninite lavas from the Dzhida terrain.Therefore,formation of pyroxenite veins most likely resulted from percolation of boninite melts through the Egiingol peridotites.Orthopyroxenite veins formed at first,followed by websterite veins.Thus,the authors assume that pyroxenite veins represent the channels for boninitic melts migration in supra-subduction environment. 展开更多
关键词 Pyroxenite vein BONINITE Partial melting Melt-rock interaction Supra-subduction zone peridotite Egiingol massif Dzhida terrain Central Asian Orogenic Belt northern Mongolia
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Co-seismic Coulomb stress changes on the northern Tanlu fault zone caused by the Tohoku-Oki M_(W)9.0 earthquake 被引量:1
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作者 Fei Chen Tai Liu +2 位作者 Yawen She Xing Huang Guangyu Fu 《Earthquake Science》 2020年第1期11-22,共12页
Based on the spherical earth dislocation theory and a fault slip model of the Tohoku-Oki M_(W)9.0 earthquake,the co-seismic Coulomb failure stress changes(ΔCFS)on the northern Tanlu fault zone at depths of 0–40 km a... Based on the spherical earth dislocation theory and a fault slip model of the Tohoku-Oki M_(W)9.0 earthquake,the co-seismic Coulomb failure stress changes(ΔCFS)on the northern Tanlu fault zone at depths of 0–40 km are calculated.By comparing two sets of results from the spherical earth dislocation theory and the semi-infinite space one,the effect of earth curvature on the calculation results is analyzed quantitatively.First,we systematically summarize previous researches related to the northern Tanlu fault zone,divide the fault zone as detailed as possible,give the geometric parameters of each segment,and establish a segmented structural model of the northern Tanlu fault zone.Second,we calculate the Coulomb stress changes on the northern Tanlu fault zone by using the spherical earth dislocation theory.The result shows the Coulomb stress changes are no more than 0.003 MPa,which proves the great earthquake did not significantly change the stress state of the fault zone.Finally,we quantitatively analyze the disparities between the results of semi-infinite space dislocation theory and the spherical earth one.The average disparity between them is about 7.7%on the northern Tanlu fault zone and is 16.8%on the Fangzheng graben,the maximum disparity on this graben reaches up to 25.5%.It indicates that the effect of earth curvature can not be ignored.So it’s necessary to use the spherical earth dislocation theory instead of the semi-infinite space one to study the Coulomb stress change in the far field. 展开更多
关键词 the northern Tanlu fault zone segmented structural model spherical earth dislocation theory the Tohoku-Oki M_(W)9.0 earthquake co-seismic Coulomb stress change(△CFS)
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Variability and Variation Characteristics of Climate in Northern Winter Wheat Zone during 1961-2004
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作者 NING Jin-hua1,SHEN Shuang-he2 1.Meteorological Training Center of Hunan Meteorological Bureau,Changsha 410125,China 2.Department of Applied Meteorological Science,Nanjing University of Information Science & Technology,Nanjing 210044,China 《Meteorological and Environmental Research》 CAS 2011年第7期30-34,共5页
[Objective] The research aimed to study the variability and variation characteristics of climate in northern winter wheat zone during 1961-2004.[Method] Based on the meteorological data (temperature,precipitation and ... [Objective] The research aimed to study the variability and variation characteristics of climate in northern winter wheat zone during 1961-2004.[Method] Based on the meteorological data (temperature,precipitation and sunshine) of 55 meteorological stations in northern winter wheat zone during 1961-2004 and the yield data of winter wheat,by using the linear regression,correlated coefficient and climatic tendency rate,the spatial and temporal evolution characteristics of agricultural climatic resources (sunshine hours,temperature and precipitation) in northern winter wheat zone were analyzed.[Result] The annual average temperature,precipitation and sunshine hours in northern winter wheat zone during 1961-2004 all presented certain zonal distribution in the space.The precipitation and temperature gradually decreased from south to north.The sunshine hours gradually increased from south to north.The annual average temperature overall presented rise trend in northern winter wheat zone in 44 years,but the rise rate had difference in the different areas.The rise of annual average temperature in the high-latitude zone was more obvious than that in the low-latitude zone.The annual rainfall overall presented decrease trend,and the tendency rate of annual precipitation had significant difference in the different areas.The decrease rates of rainfalls in the central and western areas were bigger than that in other areas.The annual sunshine hours overall presented decline trend.In most areas,the tendency rate of annual sunshine hours was negative.But there was certain difference in the different areas.The zones where the decrease amplitude was smaller scattered in the west,and included central Shaanxi,south of Shanxi and some areas in southeast of Shandong.The decrease amplitudes were bigger in south of Henan,northwest of Shandong and south of Hebei.[Conclusion] The research provided theoretical basis for understanding the historical evolution of climate in northern winter wheat zone. 展开更多
关键词 Climatic variability Variation characteristic northern winter wheat zone China
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The effects of the intertropical convergence zone on the easterly jet stream during Northern summer
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作者 Xu Liang Bao Chenglan Guangdong Institute of Tropical Marine Meteorology, Guangzhou, China Marine Environmental Forecasting Centre of SOA, Beijing, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1989年第2期209-215,共7页
In this paper, a strong 1TCZ process and an 1TCZ - absent process during FGGE in 1979 were selected for comparison to explore how they were subject to the influence of the evolution of the upper easterly jets.
关键词 In The effects of the intertropical convergence zone on the easterly jet stream during northern summer ITCZ
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Characteristics of Zhangsanying-Tongshanzi aeromagnetic anomaly zone and prospecting potential of iron deposits in northern Hebei,China
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作者 LI Wenyong LIU Yanxu +3 位作者 LU Wenfen MA Guoqing ZHANG Chongshan ZHAO Jiawei 《Global Geology》 2020年第2期99-115,共17页
Based on the latest high-precision aeromagnetic data,an aeromagnetic anomaly zone is identified at Zhangsanying--Tongshanzi in northern Hebei Province.By the potential field conversion processing,including the reducti... Based on the latest high-precision aeromagnetic data,an aeromagnetic anomaly zone is identified at Zhangsanying--Tongshanzi in northern Hebei Province.By the potential field conversion processing,including the reduction to the pole,vertical derivative,upward continuation and residual anomaly,the authors analyzed the characteristics of three typical aeromagnetic anomalies in Zhangsanying--Tongshanzi aeromagnetic anomaly zone and their geological origin.The methods include the forward and inversion methods,such as 2.5D optimization fitting and Euler deconvolution.Moreover,combined with the geological outcrop,known iron deposits,ground magnetic survey and verification,the authors studied the relationship between the aeromagnetic anomalies and iron deposits.The result shows that the Zhangsanying--Tongshanzi aeromagnetic anomaly zone is composed of 10 large magnetic anomalies with high amplitude and clear boundary.The aeromagnetic anomalies are comparable and intrinsically related to the ground magnetic anomalies and IP anomalies,indicating that the anomalies are caused by magnetite deposits.It has good magnetite prospecting potential in the Zhangsanying--Tongshanzi aeromagnetic anomaly zone. 展开更多
关键词 Zhangsanying-Tongshanzi aeromagnetic anomaly zone forward and inversion ground survey and verification prospecting potential iron deposit northern Hebei
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FLUID-ROCK INTERACTION AND MASS BALANCE IN DEFORMED ROCKS OF THE IRTISH TECTONIC ZONE,NORTHERN XINJIANG,CHINA
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《Geotectonica et Metallogenia》 1994年第Z2期31-33,共3页
关键词 ROCK FLUID-ROCK INTERACTION AND MASS BALANCE IN DEFORMED ROCKS OF THE IRTISH TECTONIC zone northern XINJIANG CHINA SiO MNO
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Geochemical characteristics of island-arc volcanic rocks in the Nan-Nam Pat-Phetchabun zone,northern Thailand
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作者 SHEN Shangyue FENG Qinglai +2 位作者 YANG Wenqiang ZHANG Zhibin Chongpom Chonglakmani 《Chinese Journal Of Geochemistry》 EI CAS 2010年第4期337-342,共6页
Late Permian-Early Triassic(P2-T1) volcanic rocks distributed on the eastern side of ocean-ridge and oceanic-island basalts in the Nan-Uttaradit zone were analyzed from aspects of petrographic characteristics,rock ass... Late Permian-Early Triassic(P2-T1) volcanic rocks distributed on the eastern side of ocean-ridge and oceanic-island basalts in the Nan-Uttaradit zone were analyzed from aspects of petrographic characteristics,rock assemblage,REE,trace elements,geotectonic setting,etc.,indicating that those volcanic rocks possess the characteristic features of island-arc volcanic rocks.The volcanic rock assemblage is basalt-basaltic andesite-andesite.The volcanic rocks are sub-alkaline,dominated by calc-alkaline series,with tholeiite series coming next.The chemical composition of the volcanic rocks is characterized by low TiO2 and K2O and high Al2O3 and Na2O.Their REE patterns are of the flat,weak LREE-enrichment right-inclined type.The trace elements are characterized by the enrichment of large cation elements such as K,Rb and Ba,common enrichment of U and Th,and depletion of Nb,Ta,Zr and Hf.The petrochemical plot falls within the field of volcanic rocks,in consistency with the plot of island-arc volcanic rocks in the Jinsha River zone of China.This island-arc volcanic zone,together with the ocean-ridge/oceanic island type volcanic rocks in the Nan-Uttaradit zone,constitutes the ocean-ridge volcanic rock-island-arc magmatic rock zones which are distributed in pairs,indicating that the oceanic crust of the Nan-Uttaradit zone once was of eastward subduction.This work is of great significance in exploring the evolution of paleo-Tethys in the Nan-Uttaradit zone. 展开更多
关键词 岛弧火山岩 地球化学特征 Al2O3含量 岩石学特征 洋岛玄武岩 玄武安山岩 钙碱性系列 泰国
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Develop an Air Emission Inventory for Potential Point Sources in Northern Key Economic Zone and Simulate Its Impacts on Air Quality in Hanoi City,Vietnam
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作者 Bang Quoc Ho Khue Vu +1 位作者 Nguyen Thoai Tam Le Ngoc Cau 《现代交通(中英文版)》 2022年第1期1-10,共10页
The Northern Key Economic region of Vietnam is a dynamic economic center that is an important economic locomotive of the North and the whole of Vietnam.In this area,large industrial parks are concentrated,attracting m... The Northern Key Economic region of Vietnam is a dynamic economic center that is an important economic locomotive of the North and the whole of Vietnam.In this area,large industrial parks are concentrated,attracting many large FDI projects.Key industries:cement production,cars-motorcycles,electronics,...Economic development entails environmental problems.The industrial sector has been identified as the number one driving force driving the growth of Hanoi city and neighboring provinces.Therefore,industrial development is one of the main causes of environmental pollution.In addition,the growth rate of industry in neighboring provinces significantly affects the air quality in Hanoi city.Some factories in Vinh Phuc,Hung Yen,Bac Ninh and Hai Duong provinces have large sources of gas emissions,potentially affecting air quality around Hanoi city.Monitoring results show that air pollution in Hanoi city is mainly caused by dust pollution,especially PM2.5 superfine dust.This is a very harmful dust to health;it is necessary to determine the cause and control solution.Therefore,the objectives of this study are:(1)inventory of potential emissions sources for industrial activities in the northern key economic region around Hanoi;(2)Simulate air spread by AERMOD model to get an overall picture of the industrial impact of surrounding provinces in Hanoi city;(3)Propose solutions to manage air quality for the city in the coming time.Simulation results for pollutants with the highest concentration of NOx for 1 hour,24 hours and the average of the year is 7.94;1.02;0.222(μg/m3);of CO for 1 hour and 8 hours are 27.616;8.89(μg/m3);of SO2 for 1 hour,24 hours and the average of the year is 4.005;0.288;0.038(μg/m3);of PM2.5 for 1 hour,24 hours and the average of the year is 0.32;0.023;0.003(μg/m3);of PM10 in 1 hour,24 hours and year average are 1.03;0.074;0.098(μg/m3). 展开更多
关键词 Air Pollution Air Emission Inventory northern Key Economic zone(NKEC) Potential Sources Industry HANOI
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Pre-drill Seismic Prediction Method for Formation Pressure for the Baiyun Sag in Deep-water Zone in Northern Part of the South China Sea
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作者 Guo Zhifeng Liu Zhen +3 位作者 Lv Rui Liu Guochang Zhang Gongcheng Shen Huailei 《石油地球物理勘探》 EI CSCD 北大核心 2012年第A02期119-126,共8页
关键词 石油 地球物理勘探 地质调查 油气资源
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南海北部水合物区HD109站位沉积物及孔隙水特征对甲烷渗漏的响应:来自元素和钡同位素的记录 被引量:1
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作者 朱碧 艾鑫宇 +1 位作者 葛璐 杨涛 《地质学报》 EI CAS CSCD 北大核心 2024年第9期2607-2618,共12页
甲烷渗漏活动及甲烷厌氧氧化作用(AOM)不仅导致特定自生矿物的形成,更会引起沉积物-孔隙水体系中元素和同位素组成的变化。本研究对南海北部水合物赋存区HD109站位开展了沉积物-孔隙水的Ba同位素及微量元素特征研究,综合分析了沉积物-... 甲烷渗漏活动及甲烷厌氧氧化作用(AOM)不仅导致特定自生矿物的形成,更会引起沉积物-孔隙水体系中元素和同位素组成的变化。本研究对南海北部水合物赋存区HD109站位开展了沉积物-孔隙水的Ba同位素及微量元素特征研究,综合分析了沉积物-孔隙水的氧化还原敏感元素(Mo、U)、Ba及Ba同位素特征对古今硫酸盐-甲烷转换带(SMTZ)及甲烷渗漏事件的指示。HD109站位孔隙水元素变化特征显示了清晰的地球化学分带,由上至下包括Fe-Mn还原带、硫酸盐还原带和硫酸盐-甲烷过渡带。沉积物Ba元素特征显示现今SMTZ上方有较为明显的钡峰(Ba/Al高值)发育,沉积物浅部Mo、U富集层位及相邻层位Ba/Al值特征综合指示了浅部古钡峰及古SMTZ的存在,代表沉积历史上甲烷渗漏通量较高事件。孔隙水δ^(138/134)Ba值普遍高于海洋颗粒钡及碎屑钡的δ^(138/134)Ba值,反映了沉积物中成岩重晶石溶解的贡献,其中,现代钡峰附近孔隙水具有明显的δ^(138/134)Ba峰值,显示孔隙水δ^(138/134)Ba对自生重晶石沉淀过程有较显著的响应。 展开更多
关键词 甲烷渗漏 Ba同位素 硫酸盐-甲烷转换带 南海北部
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黔北—滇东二叠纪锰矿主要成矿规律与成矿区带划分 被引量:1
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作者 刘志臣 周琦 +3 位作者 杨瑞东 杜远生 陈登 肖林 《矿产综合利用》 CAS 2024年第1期62-72,共11页
这是一篇地球科学领域的论文。锰矿为我国十分紧缺的战略矿产之一。黔北-滇东地区是我国二叠纪锰矿最典型的分布区,在全球晚古生代也较为少见,该区锰矿资源丰富,找矿潜力巨大,称为“遵义式锰矿”。研究表明,该区锰矿产于二叠纪茅口晚期... 这是一篇地球科学领域的论文。锰矿为我国十分紧缺的战略矿产之一。黔北-滇东地区是我国二叠纪锰矿最典型的分布区,在全球晚古生代也较为少见,该区锰矿资源丰富,找矿潜力巨大,称为“遵义式锰矿”。研究表明,该区锰矿产于二叠纪茅口晚期,分布严格受黔北裂谷盆地控制,锰矿在地堑盆地中心喷溢沉积成矿,在地垒区则无锰矿分布,矿体空间展布方向与盆地展布方向基本一致。其中,黔北遵义-黔西地区锰矿在空间上分布于盆地相区,并可分为中心相、过渡相、边缘相等三个锰矿相带,进一步指示了锰矿具体成矿位置,显示了锰矿受盆地中心控制非常明显的特点。在划分的遵义-宣威锰矿成矿带的基础上,详细划分出遵义-黔西锰矿成矿亚带中深溪—八里、龙坪—兴隆、团溪—尚稽、黔西4个锰矿矿集区,以及水城-宣威锰矿成矿亚带中水城—纳雍、格学2个锰矿矿集区。该研究成果对寻找黔北—滇东二叠纪隐伏锰矿床,开展成矿预测,具有重要的意义。 展开更多
关键词 地球科学 二叠纪锰矿 成矿规律 成矿区带 黔北—滇东
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太原盆地交城断裂带北段工程避让范围研究
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作者 曾金艳 李宏伟 +1 位作者 陈文 李自红 《大地测量与地球动力学》 CSCD 北大核心 2024年第9期919-925,共7页
在系统分析和整理交城断裂带北段探测成果的基础上,采用地质探槽剖面法、经验统计法及数值模拟法,预测评估交城断裂带北段在发生最大潜在震级M_(S)7.2地震时的同震地表破裂带宽度,探讨不同方法结果的精度和可靠性,并提出采用综合加权方... 在系统分析和整理交城断裂带北段探测成果的基础上,采用地质探槽剖面法、经验统计法及数值模拟法,预测评估交城断裂带北段在发生最大潜在震级M_(S)7.2地震时的同震地表破裂带宽度,探讨不同方法结果的精度和可靠性,并提出采用综合加权方法确定交城断裂带北段地表破裂带宽度。在此基础上综合考虑探测方法精度、断层上下盘效应等影响因素,确定交城断裂带北段工程避让区为F_(1)^(1)迹线西侧外延15.0m至F_(1)^(2)迹线东侧外延86.9m范围。该结果对交城断裂带沿线的国土规划利用、建(构)筑抗震设计具有一定的指导意义,该方法可为同类研究提供借鉴。 展开更多
关键词 交城断裂带北段 地质探槽剖面法 经验公式法 数值模拟法 地表破裂带
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渤海和黄海北部工程设计冰厚变化趋势分析
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作者 王安良 赵倩 +3 位作者 隋俊鹏 唐茂宁 王慧 刘煜 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2024年第4期659-664,共6页
针对渤海和黄海北部沿岸风电、光伏和核电等新兴能源中的工程海冰设计问题,本文研究了重现期冰厚及其在大气候背景下的变化趋势。本文分析72 a冰级时间序列表明渤海和黄海北部总体冰情等级呈明显下降趋势;在此影响下,基于20 a渤海和黄... 针对渤海和黄海北部沿岸风电、光伏和核电等新兴能源中的工程海冰设计问题,本文研究了重现期冰厚及其在大气候背景下的变化趋势。本文分析72 a冰级时间序列表明渤海和黄海北部总体冰情等级呈明显下降趋势;在此影响下,基于20 a渤海和黄海北部海冰多源观测数据和精细化海冰数值预报资料,研究发现不同重现期冰厚较之前海冰区划值存在不同程度的降低。此外,不同场址设计冰厚受当地海洋环境条件影响较大,单一参考海冰区划值可能存在较大误差。研究表明:针对特定作业地点的工程设计冰厚,需要有针对性地开展精细化评估并考虑大气候背景变化的影响,才能为相关工程海冰参数设计提供更加可靠的依据。 展开更多
关键词 渤海 黄海北部 工程海冰 冰情 设计厚度 变化趋势 重现期 海冰区划
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先秦时期北方地区民族交错地带的变迁及特点
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作者 李春梅 《内蒙古社会科学》 CSSCI 北大核心 2024年第1期130-136,共7页
先秦时期,长城以南、黄河中下游以北地区是北方各族与华夏民族交往交流交融的主要发生地。这一区域具有开放包容、丰富多元的文化样态及其文化积淀,并呈现出局部稳定和整体波动的变迁过程。近两千年的交往互动,使各民族及其文化发展都... 先秦时期,长城以南、黄河中下游以北地区是北方各族与华夏民族交往交流交融的主要发生地。这一区域具有开放包容、丰富多元的文化样态及其文化积淀,并呈现出局部稳定和整体波动的变迁过程。近两千年的交往互动,使各民族及其文化发展都得到了相应的回报,为更大规模、更大范围、更多民族的融合奠定了深厚的经济、政治、人文基础。到战国中后期,秦赵燕长城修筑后,该区域皆被纳入中原王朝的管辖范围。 展开更多
关键词 先秦 北方地区 民族交错地带
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新疆北部城市碳排放时空分异与碳平衡分区
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作者 冶建明 翟梦瑶 +1 位作者 陈志新 李禹慷 《上海国土资源》 2024年第1期93-101,共9页
研究城市土地利用碳排放时空格局与碳平衡分区,对实现碳减排和“双碳”目标至关重要。以新疆北部46个县市为研究区,利用土地利用与能源数据,通过碳排放系数法计算2000—2020年土地利用碳排放,分析碳排放量时空演变情况,对各县市进行碳... 研究城市土地利用碳排放时空格局与碳平衡分区,对实现碳减排和“双碳”目标至关重要。以新疆北部46个县市为研究区,利用土地利用与能源数据,通过碳排放系数法计算2000—2020年土地利用碳排放,分析碳排放量时空演变情况,对各县市进行碳平衡分区。结果表明:(1)碳排放量呈总体上升趋势,2016—2020年呈现指数型上升的趋势,碳吸收量缓慢下降,碳排放强度先下降后上升,碳排放量远大于碳吸收量。(2)碳排放主要来源于建设用地,天山北坡城市为主要碳排放城市,碳吸收主要来源于草地与林地,伊犁河谷地区、阿尔泰山南部等地城市为主要碳吸收城市。(3)碳排放空间相关性逐渐减弱,热点区集中分布在克拉玛依市附近,冷点区集中分布在伊犁州与阿勒泰地区。(4)依据经济承载力系数、生态承载力系数以及碳排放量划分为碳汇功能区、碳汇优化区、低碳经济区、碳源优化区和高碳控制区五个碳平衡分区。 展开更多
关键词 土地利用碳排放 时空格局 碳平衡分区 新疆北部
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基于多层次探测研究茅山断裂带北延段空间展布特征及第四纪活动性
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作者 孟科 张鹏 +2 位作者 范小平 王琛 汪晴慧 《地震科学进展》 2024年第9期559-569,共11页
本文介绍了从深至浅完成对茅山断裂北延立体式综合探测方法。使用重力场资料解译和大地电磁勘探初步定位断裂,随后通过浅层地震勘探进行精确定位,最后根据跨断点的小间距钻孔联合地质剖面探测法捕获了上断点并研判其第四纪活动性。研究... 本文介绍了从深至浅完成对茅山断裂北延立体式综合探测方法。使用重力场资料解译和大地电磁勘探初步定位断裂,随后通过浅层地震勘探进行精确定位,最后根据跨断点的小间距钻孔联合地质剖面探测法捕获了上断点并研判其第四纪活动性。研究发现:①茅山断裂带继续向北延伸入镇江市区,茅山断裂带北延段切割深度至少延伸至中地壳区域;②茅山断裂带北延段浅部区域表现出正断性质,倾向东,走向北东,视倾角约为60°,视断距约为3~5 m;③钻孔联合地质剖面探测结果显示,断点两侧基岩面落差较小,上覆第四纪地层未发现较大的起伏,未见第四纪有明显活动迹象,综合判断茅山断裂带北延段为前第四纪断裂。本项研究初步表明,茅山断裂在地理空间上可能与江苏陆域历史上两次显著的地震事件存在联系。这一发现为进一步研究该地区的发震构造特征和地震活动规律提供了新的视角,并可能对今后的相关研究有所启发。 展开更多
关键词 茅山断裂带北延段 第四纪活动性 浅层地震勘探 钻孔联合剖面
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Vegetation-Climate Relationship and Its Application in the Division of Vegetation Zone in China 被引量:38
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作者 方精云 宋永昌 +1 位作者 刘鸿雁 朴世龙 《Acta Botanica Sinica》 CSCD 2002年第9期1105-1122,共18页
Distribution of vegetation is closely coupled with climate; the climate controls distribution of vegetation and the vegetation type reflects regional climates. To reveal vegetation_climate relationships is the foundat... Distribution of vegetation is closely coupled with climate; the climate controls distribution of vegetation and the vegetation type reflects regional climates. To reveal vegetation_climate relationships is the foundation for understanding the vegetation distribution and theoretically serving vegetation regionalization. Vegetation regionalization is a theoretical integration of vegetation studies and provides a base for physiogeographical regionalization as well as agriculture and forestry regionalization. Based on a brief historical overview on studies of vegetation_climate relationships and vegetation regionalization conducted in China, we review the principles, bases and major schemes of previous vegetation regionalization and discuss on several contentious boundaries of vegetation zones in the present paper. We proposed that, under the circumstances that the primary vegetation has been destroyed in most parts of China, the division of vegetation zones/regions should be based on the distribution of primary and its secondary vegetation types and climatic indices that delimit distribution of the vegetation types. This not only reveals the closed relationship between vegetation and climate, but also is feasible practically. Although there still are divergence of views on the name and their boundaries of the several vegetation zones, it is commonly accepted that there are eight major vegetation regions in China, i.e. cold temperate needleleaf forest region, temperate needleleaf and broadleaf mixed forest region, warm temperate deciduous broadleaf forest region, subtropical evergreen broadleaf forest region, tropical monsoon forest and rain forest region, temperate steppe region, temperate desert region, and Qinghai_Xizang (Tibetan) Plateau high_cold vegetation region. Analyzing characteristics of vegetation and climate of major vegetation boundaries, we suggested that: 1) Qinling Mountain_Huaihe River line is an important arid/humid climatic, but not a thermal climatic boundary, and thus can not also be regarded as the northern limit of the subtropical vegetation zone; 2) the northern limit of subtropical vegetation zone in China is along the northern coast of the Yangtze River, from Hangzhou Bay, via Taihu Lake, Xuancheng and Tongling in Anhui Province, through by southern slope of the Dabie Mountains, to Wuhan and its west, coinciding with a warmth index ( WI ) value of 130-140 ℃·month; 3) the tropical region is limited in a very small area in southeastern Hainan Island and southern edge of Taiwan Island; and 4) considering a significant difference in climates between the southern and northern parts of the warm temperate zone, we suggested that the warm temperate zone in China is divided into two vegetation regions, deciduous broadleaf woodland region and deciduous and evergreen broadleaf mixed forest region, the Qinling Mountain_Huaihe River line being as their boundary. We also claimed that the zonal vegetation in North China is deciduous broadleaf woodland. Finally, we emphasized the importance of dynamic vegetation regionalization linked to climate changes. 展开更多
关键词 China dynamic vegetation regionalization arid/humid climate northern limit of subtropical zone Qinling Mountain_Huaihe River line thermal climate vegetation_climate relationship vegetation regionalization vegetation zone
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