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Key Physical Factors Affecting Spatial-temporal Variation of Labile Organic Carbon Fractions by Biochar Driven in Mollisols Region of Northeast China
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作者 Zhao Wei Liang Fangyuan +4 位作者 Liang Ying Zhao Hongrui Hao Shuai Wang Hongyan Wang Daqing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期28-41,共14页
Biochar is widely used to improve soil physical properties and carbon sequestration. However, few studies focuse on the impact of maize stalk biochar on labile organic carbon(LOC) pool and the relationship between phy... Biochar is widely used to improve soil physical properties and carbon sequestration. However, few studies focuse on the impact of maize stalk biochar on labile organic carbon(LOC) pool and the relationship between physical properties and LOC fractions. A field positioning experiment was performed in Mollisols region of Northeast China to evaluate the influence of maize stalk biochar on the spatial distribution and temporal changes of physical properties and LOC fractions. Maize stalk biochar treatments included C1(1.5 kg·hm^(-2)), C2(3 kg·hm^(-2)), C3(15 kg·hm^(-2)), C4(30 kg·hm^(-2)), and CK(0). The results showed that maize stalk biochar increased soil water contents(SWC) and soil porosity(SP), but reduced bulk density(BD). Maize stalk biochar reduced dissolved organic carbon(DOC) contents in the 0-20 cm soil layer, ranging from 0.25 g·kg^(-1) to 0.31 g·kg^(-1) in harvest period, while increased in the 20-40 cm soil layer. In addition, the application of biochar had a significant impact on the spatial distribution and temporal change of SWC, BD, SP, DOC, hot-water extractable carbon(HWC), acid hydrolyzed organic carbon(AHC Ⅰ, Ⅱ), and readily oxidized organic carbon(ROC). High amounts of maize stalk biochar up-regulated the contents of soil organic carbon SOC, HWC, AHC Ⅰ, AHC Ⅱ, and ROC. In addition, SWC and SP were the key physical factors to affect LOC fractions. In conclusions, maize stalk biochar could improve physical properties, and then influence LOC fractions, and maize stalk biochar could be used as an organic amendment for restoring degraded soils governed by their rates of addition. 展开更多
关键词 maize stalk biochar labile organic carbon fraction Mollisols region soil physical property dissolved organic carbon
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Spheres of Urban Influence and Factors in Beijing-Tianjin-Hebei Metropolitan Region Based on Viewpoint of Administrative Division Adjustment 被引量:3
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作者 ZHU Jianhua CHEN Xi CHEN Tian 《Chinese Geographical Science》 SCIE CSCD 2017年第5期709-721,共13页
The coordinated development of Beijing, Tianjin and Hebei has been elevated as China's important strategy. And, the priority in considering how to bring the maximum effect of their coordinated development into pla... The coordinated development of Beijing, Tianjin and Hebei has been elevated as China's important strategy. And, the priority in considering how to bring the maximum effect of their coordinated development into play is to delineate the spheres of urban influence with regard to the cities in the Beijing-Tianjin-Hebei Metropolitan Region. By building an evaluation index system of urban comprehensive strength, this paper applies the principal component analysis method to determine centrality strength of the cities, and the breakpoint theory and weighted Voronoi diagram to identify the spheres of urban influence in all central cities of the region. Results show that 13 central cities within the region greatly differ in strength, which can be classified into four tiers and that the spheres of urban influence do not have a high goodness of fit with administrative jurisdiction scope. Cities like Beijing, Tianjin, Shijiazhuang and Handan have larger spheres of urban, spheres of urban influence in Tangshan and Qinhuangdao are basically consistent with their administrative jurisdiction scopes, and seven cities including Langfang and Baoding have smaller spheres of urban influence. So according to these cities' comprehensive strength and spheres of influence, the region can be divided into five plates: Beijing, Tianjin, Shijiazhuang, Tangshan and Handan. The major influence factors for inconsistency between spheres of urban influence and spheres of jurisdiction include difference in urban administrative ranking, small number of central cities with weak strength, discrepancy in the number of counties under jurisdiction, unreasonable spheres of jurisdiction and diversity in topographical conditions. In order to solve the imbalance in the spheres of urban influence and those of jurisdiction and better facilitate the coordinated development of the region, it is advised to adjust administrative areas so as to obtain more optimized urban spatial layout and more reasonable urban scale hierarchy system. 展开更多
关键词 spheres of urban influence urban comprehensive strength adjustment of administrative divisions weighted Voronoi diagram Beijing-Tianjin-Hebei Metropolitan region
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Study on the Improvement Strategies of Physical Environment for Square in Severe Cold Regions' Rural Areas 被引量:1
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作者 Xin-Yu Zhang Hong Jin 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第4期18-23,共6页
To improve the comfortable physical environment for square in severe cold regions' rural areas. This paper applies the methods of questionnaires,field testing and statistical analysis to compare and analyze two di... To improve the comfortable physical environment for square in severe cold regions' rural areas. This paper applies the methods of questionnaires,field testing and statistical analysis to compare and analyze two different square cases of Qingyunpu in Liaoning Province,and conclude the main factors which affect the physical environmental comfort. The improvement strategies for physical environment of rural square are put forward from the aspects of site selection,road position,orientation,landscape design,and ground pavement material selection,aiming to provide the design basis for the physical environment of square in severe cold regions' rural areas. 展开更多
关键词 rural areas of severe cold regions SQUARES physical environment improvement strategies
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Effects of Straw and Biochar Returned to the Soil on Soil Physical Properties and pH Value in Cold Rice Region 被引量:1
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作者 Yuefeng CUI Hongru SHI +5 位作者 Aonan GUO Guocai SUN Guiyan WANG Jian WANG Wenjia HUANG Tiegang LU 《Asian Agricultural Research》 2021年第2期27-32,共6页
[Objectives]In order to explore the feasibility of using straw and biochar returned to the soil to improve soil physical properties and pH value in cold rice regions of China.[Methods]the effects of straw directly ret... [Objectives]In order to explore the feasibility of using straw and biochar returned to the soil to improve soil physical properties and pH value in cold rice regions of China.[Methods]the effects of straw directly returned to the soil and charred straw(biochar)returned to the soil on soil bulk density,porosity,temperature and pH value of cold paddy soil were studied in this paper.[Results]The results showed that compared with conventional production,straw(6 t/ha),a small amount of biochar(2 t/ha)and a large amount of biochar(40 t/ha)returned to the soil reduced paddy soil bulk density at different growth stages by 6.02%-11.86%,2.69%-6.67%and 8.58%-11.32%,respectively,increased total porosity by 7.41%-14.93%,3.19%-8.38%and 9.81%-14.27%,respectively,and increased aeration porosity by 22.28%-192.11%,17.80%-92.11%and 52.44%-157.11%,respectively.Straw and a small amount of biochar returned to the soil had no significant effect on soil temperature and pH value of paddy field,but a large amount of biochar returned to the soil could significantly increase soil temperature by 5.13%-8.79%and pH value by 3.15%-5.96%in the later stage of rice growth.[Conclusions]The straw and biochar returned to the soil could reduce soil bulk density,increase total porosity and aeration porosity,and only a large amount of biochar returned to the soil could significantly increase soil temperature and pH value. 展开更多
关键词 STRAW BIOCHAR Cold rice region Soil physical properties Soil pH value
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REFORM AND TEACHING QUALITY—EXEMPLIFICATION OF REGIONAL PHYSICAL GEOGRAPHY
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作者 李春芬 《Chinese Geographical Science》 SCIE CSCD 1992年第3期83-89,共7页
There are a number of factors involved in teaching quality. Among them teaching materials or textbooks are of primary importance, the presentation of which relies first of all on the viewpoint to structure the content... There are a number of factors involved in teaching quality. Among them teaching materials or textbooks are of primary importance, the presentation of which relies first of all on the viewpoint to structure the contents geographically. Whatever branch of geography you are teaching or in pursuit, geographical viewpoint is vitally important. This paper in discussing innovation of geographical education about these institutions with the course of regional physical geography as an example. The higher education of our discipline is in pressing need of innovation and thereby upgrading quality. 展开更多
关键词 TEACHING REFORM TEACHING QUALITY regionAL physical GEOGRAPHY
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Effects of cementation on physical properties of clastic rock-originated weathering crust reservoirs in the Kexia region,Junggar Basin,NW China
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作者 Changhai Gao Shida Meng +2 位作者 Jiahao Zhang Jian Wang Yifei Sun 《Energy Geoscience》 2023年第1期74-82,共9页
Cements are widely developed in clastic rock-originated weathering crust(CWC)reservoirs in the Kexia region along the northwestern margin of the Junggar Basin and significantly affect reservoir physical properties and... Cements are widely developed in clastic rock-originated weathering crust(CWC)reservoirs in the Kexia region along the northwestern margin of the Junggar Basin and significantly affect reservoir physical properties and oil and gas distribution in this area.Focusing on the CWC reservoirs at the top of both the Permian Jiamuhe Formation and the Triassic Karamay Formation,this study analyzed the types and characteristics of cements in the reservoirs and explored their effects on reservoir physical properties based on thin sections,SEM images,XRD results,and tests of physical properties.The main results are as follows.The cements in the CWC reservoirs in Kexia region mainly consist of carbonate minerals(41.5%),clay minerals(27.8%)and zeolite minerals(30%),as well as small amount of siliceous minerals.Among them,the carbonate minerals are dominated by siderite and calcite,the clay minerals mainly include kaolinite,interstratified illite/smectite(I/S)and chlorite,and the zeolite minerals primarily comprise heulandite and laumontite.These different types of multiphase cements are generally paragenetic or associated and affect reservoir physical properties to different degrees.Specifically,the carbonate and clay cements of the early diagenetic stage reduced the reservoirs’average porosity from 21%to 15%.The dissolution of some carbonate and zeolite cements in the early A substage of the middle diagenetic stage restored the average porosity to 18%,and the cementation in the late A substage decreased the average porosity to 13%again,of which about 4%was reduced by carbonate cements.The average porosity of the CWC reservoirs gradually decreased to the current value of approximately 10%in the B substage of the middle diagenetic stage.The impact of cementation on the CWC reservoirs can reach as far as 70 m below the unconformity.Moreover,the types and contents of cements vary with their depth below the unconformity surface,leading to the development of multiple zones with high cement content and the differentiated oil and gas distribution. 展开更多
关键词 Clastic rock-originated weathering crust Cementation characteristic physical properties Pore evolution Kexia region Junggar Basin
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Inter-administrative region coordination in the new urban district construction: A case study of Gui-An New District
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作者 ZENG Yu-hang LIU Yan-yu 《Ecological Economy》 2015年第3期243-250,共8页
The construction of the new urban district is one of the main strategies to extend the urban space in China. In recent years, with the performance of the national balanced development strategy of the regional economic... The construction of the new urban district is one of the main strategies to extend the urban space in China. In recent years, with the performance of the national balanced development strategy of the regional economics, the inter-administrative regional construction of the new urban district has been a tendency aiming to remove the administrative division barrier and facilitate the regional economic development. However, problems also arise in the new urban district under the background of the inter-administrative region such as the predicament caused by the ubiquitous regional economic cooperation and competition as well as the public governance, the lack of the management main body qualifi cation and the monotonous means of coordination. Referring to the experiences of the US in the inter-administrative region administration in the metropolitan area, the author is to put forward countermeasures and suggestions from such two aspects as the management system and the working mechanism. 展开更多
关键词 URBAN new dstrict inter-administrative region coor
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Assessing performance of cross-administrative environment governance based on PSR model:An empirical analysis of the Beijing-Tianjin-Hebei region
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作者 SI Lin-bo LI Xue-ting 《Ecological Economy》 2019年第4期242-256,共15页
As an effective environment governance tool,environment governance performance evaluation is an important content and method to promote the modernization of environment governance system and governance ability.The env... As an effective environment governance tool,environment governance performance evaluation is an important content and method to promote the modernization of environment governance system and governance ability.The environmental pollution of the Beijing-Tianjin-Hebei region has typical cross-administrative characteristics.Based on the analysis of the major environmental pollution problems in the Beijing-Tianjin-Hebei region,according to the international environment governance PSR model,a performance evaluation system that applies to the environment governance of Beijing-Tianjin-Hebei region is established.Meanwhile,the principal component analysis method is applied to conduct an empirical analysis of the environmental governance panel data for the 13 major cities in the Beijing-Tianjin-Hebei region from 2014 to 2016.The results show that most of the cities in the Beijing-Tianjin-Hebei region attach great importance to reduction of emission and pollutants,continuously alleviating the stress of environmental governance.However,the overall improvement of the environment governance performance in Beijing-Tianjin-Hebei region has presented a polarization imbalance.There is a clear tendency for subjective biases in the implementation of environment governance and a lack of comprehensive and systematic governance.According to the environment governance performance evaluation result of Beijing-Tianjin-Hebei region,the cross-administrative regional environment governance should improve the environment governance performance evaluation system as soon as possible,strengthen the consistency of the environment governance objectives,and implement comprehensive and systematic governance for the regional environment. 展开更多
关键词 cross-administrative GOVERNANCE BEIJING-TIANJIN-HEBEI region environment GOVERNANCE PERFORMANCE evaluation PSR model
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ANALYSIS ON SPATIAL DIFFERENCE OF LAND USECHANGE BASED ON PHYSICAL AND CULTURALLANDSCAPE ATTRIBUTES──A Case Study at Mongolian AutonomousCounty of Qian Gorlos, Jilin Province 被引量:3
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作者 HUANG Fang, LIU Xiang-nan, XU Hong-mei, ZHANG Shu-wen, ZHANG Yang-zhen (Changchun Institute of Geography, the Chinese Academy of Sciences, Changchun 130021, P. R. China School of Urban and Environmental Science, Northeast Normal University, Changchun 13 《Chinese Geographical Science》 SCIE CSCD 2001年第1期50-56,共7页
Land use changes are regarded as landscape pattern change driven by many interactive natural and social-economic factors. Different combination of physical geographical elements induced the difference of spatio-tempor... Land use changes are regarded as landscape pattern change driven by many interactive natural and social-economic factors. Different combination of physical geographical elements induced the difference of spatio-temporal pattern of land use change. There are four physical geographical regions in Mongolian Autonomou County of Qian Gorlos of Jilin Province. Based on spatial analysis and statistical analysis, we conclude that the primary pattern of land use and the tendency of land use changes are all different in four physical geographical regions. During 1987 – 1996, the dominant land use change processes were from grassland or forest to arableland, from unused land to paddy and grassland to unused land. Though land use change is mainly affected by social and economic condition in short period, the composite characters of physical geographical elements controls land use dynamic process. The relationship between land use dynamic process and the character of physical geographical units differ in different regions. Possible human impacts on land use change are explored with application of buffer areas of series distance along main roads and radius around main settlements. A few models are built to describe the relationship between land use spatial change rates and distance to road and settlements. According to our result, the relationship with the proximity to roads was a negative liner function, with the change rate decreasing rapidly when moving away from roads. Within a distance of less 7.5km from main traffic lines, land use changes occur red more. The bulk of grassland was apt to be opened up for cultivation around the settlements and the transformation from dryland to paddy occurred within the distance of 1km away from settlements. 展开更多
关键词 land use change physical geographic region land use dynamic process effective coefficient cultural landscape variable
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Banded Iron Formations (BIFs) and Associated Sediments Do Not Reflect the Physical and Chemical Properties of Early Precambrian Seas
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作者 Zeev Lewy 《International Journal of Geosciences》 2012年第1期226-236,共11页
Ring-in-ring structures in Australian Early Precambrian banded iron formation (BIF) were identified as bubbling mud wavelets, which lithified during temporary exposure, contradicting the alleged BIF deep ocean origin.... Ring-in-ring structures in Australian Early Precambrian banded iron formation (BIF) were identified as bubbling mud wavelets, which lithified during temporary exposure, contradicting the alleged BIF deep ocean origin. Least altered BIFs consist of alternating chert laminae with, and without iron oxides (or carbonates). They were precipitated during on-and-off periods of ferrous iron oxidation controlled by microbial oxygenic photosynthetic activity during solar illumination, which stopped during darkness as characterizing the Polar Regions, thus forming genuine annual varves. This polar environment is further corroborated by the magnetite-hematite-magnetite microcrystal layers in the iron-rich laminae reflecting mid-spring-summer-autumn changes in solar radiation, and by diamictite at the end of the sequence deposited from melting glaciers when the continental plate shifted to lower latitudes. BIF sequences in various countries comprise evaporates. They attest to intensive evaporation of the warm hydrothermal solution in restricted shallow lakes under the freezing dry climate up to silica (geyserite) precipitation referred to chert. The existence of oceans, mid-ocean-ridges and island arcs during the Early Precambrian results from the misinterpreted oceanic origin of BIFs and the Phanerozoic occurrences of the associated mafic-ultramafic basalt flows (Greenstone Belt). 展开更多
关键词 Early PRECAMBRIAN BIF NON-MARINE POLAR regions physical and Chemical Control
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CWRF-based ensemble simulation of tropical cyclone activity near China and its sensitivity to the model physical parameterization schemes
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作者 Wenru Shi Haishan Chen Xin-Zhong Liang 《Atmospheric and Oceanic Science Letters》 CSCD 2021年第1期22-26,共5页
To evaluate the downscaling ability with respect to tropical cyclones(TCs)near China and its sensitivity to the model physics representation,the authors performed a multi-physics ensemble simulation with the regional ... To evaluate the downscaling ability with respect to tropical cyclones(TCs)near China and its sensitivity to the model physics representation,the authors performed a multi-physics ensemble simulation with the regional Climate-Weather Research and Forecasting(CWRF)model at a 30 km resolution driven by ERA-Interim reanalysis data.The ensemble consisted of 28 integrations during 1979-2016 with varying CWRF physics configurations.Both CWRF and ERA-Interim can generally capture the seasonal cycle and interannual variation of the TC number near China,but evidently underestimate them.The CWRF downscaling and its multi-physics ensemble can notably reduce the underestimation and significantly improve the simulation of the TC occurrences.The skill enhancement is especially large in terms of the interannual variation,which is most sensitive to the cumulus scheme,followed by the boundary layer,surface and radiation schemes,but weakly sensitive to the cloud and microphysics schemes.Generally,the Noah surface scheme,CAML(CAM radiation scheme as implemented by Liang together with the diagnostic cloud cover scheme of Xu and Randall(1996))radiation scheme,prognostic cloud scheme,and Thompson microphysics scheme stand out for their better performance in simulating the interannual variation of TC number.However,the Emanuel cumulus and MYNN boundary layer schemes produce severe interannual biases.Our study provides a valuable reference for CWRF application to improve the understanding and prediction of TC activity. 展开更多
关键词 Tropical cyclone Ensemble simulation physical parameterization schemes regional downscaling
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What are the underlying causes and dynamics of land use conflicts in metropolitan junction areas?A case study of the central Chengdu–Chongqing region in China
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作者 TIAN Junfeng WANG Binyan +1 位作者 QIU Cheng WANG Shijun 《Regional Sustainability》 2024年第3期81-98,共18页
Land use conflicts(LUCs),as a spatial manifestation of the conflicts in the human-land relationships,have a profound impact on regional sustainable development.For China’s metropolitan junction areas(MJAs),the existe... Land use conflicts(LUCs),as a spatial manifestation of the conflicts in the human-land relationships,have a profound impact on regional sustainable development.For China’s metropolitan junction areas(MJAs),the existence of“administrative district economies”has made the issue of LUCs more prominent.Based on a case study of the central Chengdu–Chongqing region,we conducted an exploratory spatial data analysis of the evolutionary process of regional LUCs.Furthermore,structural equation modeling was utilized to analyze the dynamic mechanism of LUCs in MJAs,with a particular emphasis on exploring the influences of administrative boundary.The results showed that from 2010 to 2020,LUCs in the central Chengdu–Chongqing region continued to worsen,and the spatial process conflict and spatial structure conflict indices increased by more than 30.0%.The intensification of LUCs in the central Chengdu–Chongqing region from 2010 to 2020 was mainly the result of the deterioration of conflicts in evaluation units with low conflict levels.LUCs in China’s metropolitan areas generally presented a circular gradient distribution,weakening from the core to the periphery,but there were some strong isolated conflict zones in the outer regions.LUCs in China’s MJAs were the result of interactions among multiple factors,e.g.,natural environment,socio-economic development,policy and institutional processes,and administrative boundary effects.Administrative boundary affected the flow of socio-economic elements,changing the supply-and-demand competition of stakeholders for land resources,consequently exerting an indirect influence on LUCs.This study advances the theory of the dynamic mechanism of LUCs,and provides theoretical support for the governance of these conflicts in transboundary areas. 展开更多
关键词 Land use conflicts Urban agglomerations administrative boundary Land resources Structural equation modeling(SEM) Central Chengdu-Chongqing region
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Actively Promoting Regional Space Cooperation——Vice Administrator, Loan Enjie headed a delegation to attend the Second Asia-Pacific Conference on Multilateral Cooperation in Space Technology and Applications
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作者 Zhang Lihui 《Aerospace China》 1995年第1期14-15,共2页
A Chinese delegation of 24 persons headed by Mr. Luan Enjie, Vice Administrator of China National Space Administration (CNSA) attended the Second Asia-Pacific Conference on Multilateral Cooperation in Space Technology... A Chinese delegation of 24 persons headed by Mr. Luan Enjie, Vice Administrator of China National Space Administration (CNSA) attended the Second Asia-Pacific Conference on Multilateral Cooperation in Space Technology and Applications held at Islamabad, the Capital of Pakistan from April 22 to 26, 1995. Following the First AsiaPacific Workshop held in Beijing in December, 1992, and the First Asia-Pacific Conference on Multilateral Cooperation in 展开更多
关键词 Asia Loan Enjie headed a delegation to attend the Second Asia-Pacific Conference on Multilateral Cooperation in Space Technology and Applications Vice administrator Actively Promoting regional Space Cooperation
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Multi-year Simulations and Experimental Seasonal Predictions for Rainy Seasons in China by Using a Nested Regional Climate Model (RegCM_NCC). Part Ⅰ: Sensitivity Study 被引量:40
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作者 丁一汇 史学丽 +6 位作者 刘一鸣 刘艳 李清泉 钱永甫 苗蔓倩 翟国庆 高昆 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2006年第3期323-341,共19页
A modified version of the NCAR/RegCM2 has been developed at the National Climate Center (NCC), China Meteorological Administration, through a series of sensitivity experiments and multi-year simulations and hindcast... A modified version of the NCAR/RegCM2 has been developed at the National Climate Center (NCC), China Meteorological Administration, through a series of sensitivity experiments and multi-year simulations and hindcasts, with a special emphasis on the adequate choice of physical parameterization schemes suitable for the East Asian monsoon climate. This regional climate model is nested with the NCC/IAP (Institute of Atmospheric Physics) T63 coupled GCM to make an experimental seasonal prediction for China and East Asia. The four-year (2001 to 2004) prediction results are encouraging. This paper is the first part of a two-part paper, and it mainly describes the sensitivity study of the physical process paraxneterization represented in the model. The systematic errors produced by the different physical parameterization schemes such as the land surface processes, convective precipitation, cloud-radiation transfer process, boundary layer process and large-scale terrain features have been identified based on multi-year and extreme flooding event simulations. A number of comparative experiments has shown that the mass flux scheme (MFS) and Betts-Miller scheme (BM) for convective precipitation, the LPMI (land surface process model I) and LPMII (land surface process model Ⅱ) for the land surface process, the CCM3 radiation transfer scheme for cloud-radiation transfer processes, the TKE (turbulent kinetic energy) scheme for the boundary layer processes and the topography treatment schemes for the Tibetan Plateau are suitable for simulations and prediction of the East Asia monsoon climate in rainy seasons. Based on the above sensitivity study, a modified version of the RegCM2 (RegCM_NCC) has been set up for climate simulations and seasonal predictions. 展开更多
关键词 regional climate model sensitivity experiment physical process parameterization MEI-YU
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Sedimentary Facies and Distribution of Reservoir Rocks from the Feixianguan Formation in the Daxian-Xuanhan Region, NE Sichuan 被引量:11
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作者 MA Yongsheng MOU Chuanlong +2 位作者 GUO Xusheng YU Qian TAN Qinyin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第1期137-151,共15页
The Lower Triassic Feixianguan Formation in the Daxian-Xuanhan region, northeastern Sicbuan is interpreted to be a carbonate platform intermediate between the West Hubei-East Cbongqing marine basin and Guangyuan-Wangc... The Lower Triassic Feixianguan Formation in the Daxian-Xuanhan region, northeastern Sicbuan is interpreted to be a carbonate platform intermediate between the West Hubei-East Cbongqing marine basin and Guangyuan-Wangcang marine basin. Outcrops, well logs and seismic data have disclosed that three sedimentary facies can be identified for the formation: open platform, platform exposed shoal and restricted platform facies. During the early stage of deposition of the Feixianguan Formation, there existed a sedimentary framework all the same as the Late Permian one: open platform in the west, and platform exposed shoal, restricted platform and open platform eastwards. The gradual increase of the shoal area permitted eastward migration of the shoal facies. During the deposition of the third member of the Feixianguan Formation, the study area was invaded by temporary transgressions. Till the deposition of the fourth member of the formation, the study area was prevailed over the unified restricted platform deposits, as indicated by the sedimentary model for the typical carbonate platform shoal deposits. The reservoir rocks in the Feixianguan Formation consist mostly of solution opening dolostone, and the rock types are assembled by oolitic dolostone, residual oolitic dolostone and sucrosic residual oolitic medium- to coarse-grained dolostone. The deep and shallow dual laterologs show relatively high resistivity, clear amplitude differences and time difference saltation of acoustic waves in some intervals. The seismic responses are indicated by low-frequency and highly variable amplitudes and chaotic reflection configurations. The reservoir rocks are characterized by high porosity-high permeability and medium porosity-medium permeability, showing a marked correlation between porosity and permeability. Solution openings are extremely developed in the reservoir rocks, including cast pores, intergranular solution openings, intercrystal pores, intercrystal solution openings, solution openings (caves) and minute fissures. Macropores and coarse pore throats are common. The reservoir rocks are apparently controlled by sedimentary facies in distribution patterns. Vertically, they occur dominantly in the second and first members of the Feixianguan Formation, and laterally in the platform exposed shoals and restricted platforms, where good natural gas potential is expected. 展开更多
关键词 Daxian-Xuanhan region Feixianguan Formation carbonate platform exposed shoal physical property distribution of reservoir rocks
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Progress in polar upper atmospheric physics research in China 被引量:4
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作者 LIU Ruiyuan YANG Huigen 《Advances in Polar Science》 2012年第2期55-71,共17页
The Chinese Antarctic Great Wall, Zhongshan, Kunlun and Arctic Yellow River stations have unique geographical locations, well suited to carry out polar upper atmospheric observations. This paper reviews the tremendous... The Chinese Antarctic Great Wall, Zhongshan, Kunlun and Arctic Yellow River stations have unique geographical locations, well suited to carry out polar upper atmospheric observations. This paper reviews the tremendous history of nearly 30 years of Chinese polar expeditions and major progress in polar upper atmospheric physics research. This includes the polar upper atmospheric physics conjugate observation system at Zhongshan Station in the Antarctic and Yellow River Station in the Arctic, and original research achievements in polar ionospheric fields, aurora and particle precipitation, the polar current system, polar plasma convection, geomagnetic pulsations and space plasma waves, inter-hemispheric comparisons of the space environment, space weather in polar regions, power spectrum of the incoherent scatter radar, ionospheric heating experiments and polar meso- spheric summer echoes, polar ionosphere-magnetosphere numerical simulation and others. Finally, prospects for Chinese polar upper atmospheric physics research are outlined. 展开更多
关键词 upper atmospheric physics space physics geospace polar region IONOSPHERE AURORA
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Comparison of WRF Model Physics Parameterizations over the MENA-CORDEX Domain 被引量:3
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作者 George Zittis Panos Hadjinicolaou Jos Lelieveld 《American Journal of Climate Change》 2014年第5期490-511,共22页
We investigated the performance of 12 different physics configurations of the climate version of the Weather, Research and Forecasting (WRF) Model over the Middle East and North Africa (MENA) domain. Possible combinat... We investigated the performance of 12 different physics configurations of the climate version of the Weather, Research and Forecasting (WRF) Model over the Middle East and North Africa (MENA) domain. Possible combinations among two Planetary Boundary Layer (PBL), three Cumulus (CUM) and two Microphysics (MIC) schemes were tested. The 2-year simulations (December 1988-November 1990) have been compared with gridded observational data and station measurements for several variables, including total precipitation and maximum and minimum 2-meter air temperature. An objective ranking method of the 12 different simulations and the selection procedure of the best performing configuration for the MENA domain are based on several statistical metrics and carried out for relevant sub-domains and individual stations. The setup for cloud microphysics is found to have the strongest impact on temperature biases while precipitation is most sensitive to the cumulus parameterization scheme and mainly in the tropics. 展开更多
关键词 WRF physics PARAMETERIZATIONS regional Climate Modeling Sensitivity MENA CORDEX
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Regional difference and dynamic mechanism of locality of the Chinese farming-pastoral ecotone based on geotagged photos from Panoramio 被引量:1
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作者 WANG Fang LI Yixi +1 位作者 DONG Ying ZHU Xiaohua 《Journal of Arid Land》 SCIE CSCD 2018年第2期316-333,共18页
Cross-regional locality research reflects the influences of natural environment and the human activities due to the abundant land types and the multiple landscape combinations in related regions. The Chinese farming-p... Cross-regional locality research reflects the influences of natural environment and the human activities due to the abundant land types and the multiple landscape combinations in related regions. The Chinese farming-pastoral ecotone is a typical large-scale region but few studies were conducted. This research contributed to the understanding of cross-regional locality of the Chinese farming-pastoral ecotone from different scales, including national, sectional, and provincial administrative units by utilizing geotagged photos(GTPs) obtained from the Panoramio website. The major results were as follows:(1) the locality elements of the Chinese farming-pastoral ecotone included 52 free nodes classified into 8 types of scene attributes;(2) there were huge differences between locality elements of different regions, and there was a negative correlation between the similarity degree of elements of different provinces and their spatial distances;(3) the Chinese farming-pastoral ecotone could be divided into the northern, central and southern sections, whose localities had differences in element constitution, association structure and the strength of elements, system stability and the anti-interference capability; and(4) the evolution of the localities of the northern and central sections was mainly influenced by human activities, while the locality of southern section retained more natural features. On a theoretical level, this research aimed to establish the research methodology of locality from the perspective of open data on the web with strong operability and replicability. On a practical level, this research could enrich the structuring recognition of the locality of the Chinese farming-pastoral ecotone and the comprehension of its dynamic mechanism. The results provide a reference for locality differentiation protection and the development of a cross-regional scale. 展开更多
关键词 administrative units geotagged photos LANDSCAPE LOCALITY NETWORKS regional differences
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EVOLUTION AND DIFFERENTIATION OF THE PHYSICO-EOGRAPHICAL ENVIRONMENT OF THE QINGHAI-XIZANG (TIBETAN) PLATEAU 被引量:1
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作者 Zheng Du Li BinGyuan(InstitUte of Geography, CAS, BejiNg 100101People’s Repubilc of CHina) 《Journal of Geographical Sciences》 SCIE CSCD 1994年第Z1期34-47,共14页
The intense uplift of the Qinghai-Xizang Plateau givesrise to drastic changes of natural environment and distinctdifferentiation of the Plateau proper. This paper focuses on theevolution of subtropical environment at ... The intense uplift of the Qinghai-Xizang Plateau givesrise to drastic changes of natural environment and distinctdifferentiation of the Plateau proper. This paper focuses on theevolution of subtropical environment at low altitude to frigidenvironment at high altitude of the region since Pliocene and thechanges effected by cold-warm amplitude bf global change. Bycomparative study on the structure-type of the altitudinal belt, adistributional model diagram with close relevance to highlanduplift effect has been generalized. Based on regjonaldifferentiation of the Qinghai-Xizang Plateau, a number ofstriking geo-ecological phenomena such as moisture corridor, dryvalleys and high cold-arid core area are investigated anddiscussed. 展开更多
关键词 paleogeographical environmental evolution structure-type altitudinal belt physical regional differentiation Qinghai-Xizang Plateau
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Regional Interdependence: A Model That Needs to Be Integrated in the Functional Evaluation and Physiotherapy Treatment—Part 1 被引量:2
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作者 Luca Collebrusco Rita Lombardini Giovanna Censi 《Open Journal of Therapy and Rehabilitation》 2016年第3期117-124,共8页
Background: Rehabilitation is increasing the need to use codes in order to make both a functional diagnosis and a therapeutic intervention as correct and targeted as possible. Thus, it is very important to integrate t... Background: Rehabilitation is increasing the need to use codes in order to make both a functional diagnosis and a therapeutic intervention as correct and targeted as possible. Thus, it is very important to integrate the model of Regional Interdependence (RI) in the classical rehabilitation evaluation methods, since it will be of help for understanding, solving dysfunctional problems, and improving the patient management, which is often difficult given the fact that there is no concordance on functional tests and timing of treatments. The RI should be added to the functional evaluation each time that a patient presents symptoms in a specific location, which interest also distal regions. This is due to the functional and anatomical connections of the myofascial system, vascular, autonomic nervous system (ANS), the peripheral nervous system (PNS) and the neuro-immunoendocrine system. The RI can be summarized into three groups that are correlated when it comes to applying it practically: upper, bottom and front quadrant. Adding the concept of RI to the clinical and therapeutically practice, it would have positive effects on improving the quality of life and allocate better health’s resources. The aim of this paper is to make the functional assessment in clinical practice faster and more standardized. 展开更多
关键词 physical Therapy regional Interdependence REHABILITATION NUTRITION
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