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The Source of Groundwater Recharge Based on Entropy Theory in the Arid Areas of North China 被引量:1
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作者 CHEN Jiansheng XU Yi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第1期390-391,共2页
Objective Any natural system is constantly exchanging material, energy and information with the environment, and all tkese processes follow the basic law of thermodynamics, with no exception of groundwater recharge a... Objective Any natural system is constantly exchanging material, energy and information with the environment, and all tkese processes follow the basic law of thermodynamics, with no exception of groundwater recharge and discharge process. On the basis of the principle of the first law of thermodynamics, the reverse geochemical simulation method is widely used in the study of groundwater recharge, runoff and drainage process. However, some studies only consider the material conservation in theprocess, but ignore the probability of the transformation. 展开更多
关键词 the Source of Groundwater Recharge Based on Entropy theory in the Arid areas of north china
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Determination of active units with different kinematic property and their activity pattern in North China based on the data from GPS remeasurements 被引量:2
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作者 杨国华 韩月萍 张凤兰 《Acta Seismologica Sinica(English Edition)》 CSCD 2001年第1期1-11,共11页
Based on the high-accuracy data obtained from the GPS measurements carried out in 1992, 1995 and 1996, the isochronous active units with different kinematic property inside the North China area have been distinguished... Based on the high-accuracy data obtained from the GPS measurements carried out in 1992, 1995 and 1996, the isochronous active units with different kinematic property inside the North China area have been distinguished, 4 active units and 1 transition zone with distinct differential movement have been determined. They are Ordos-Yinshan unit, Yanshan unit, Shanxi-Hebei-Shandong (Jin-Ji-Lu) unit, Jiaodong-Liaoning-Shandong (Jiao-Liao-Lu) unit and Yanshan-Hebei (Yan-Ji) transition zone. The relative movements among the neighboring units in this period have been given. ① The compressive movement between Ordos-Yinshan unit and Yanshan unit is not obvious with an amount of 0.4(1.3 mm/a.②in-Ji-Lu unit moves E40(S off the Ordos-Yinshan unit and the magnitude is 4.4(1.0 mm/a. ③elative to the Yan-Ji transition zone of differential movement, Yanshan unit shifts W38(N with a value of 2.4(1.3 mm/a and Jin-Ji-Lu unit moves eastward 35( by south with an amount of 2.3(0.9 mm/a. ④Jin-Ji-Lu unit has a tensional left-lateral movement of 4.7(1.4 mm/a in the direction of E37(S relative to Yanshan unit. ⑤ Some area near Tanlu belt which is located in the southern part of Jin-Ji-Lu block has a southward movement 14( by west with a magnitude of 1.5(1.1 mm/a off the Jin-Ji-Lu unit. ⑥ Relative to Jin-Ji-Lu unit, Jiao-Liao-Lu unit has a trend of clockwise movement with a tensional right-lateral motion at the north end which neighbors Yanshan unit and a compressive motion at the south end. It should be noted that the errors given in the paper are obtained based on the divergence among the displacements of the sites in the unit, rather than the value calculated from the displacement error of the sites. The analyzed results indicate that: ① Shanxi tectonic zone and Yan-Ji transition zone are the major tectonic active zones to show the frame and magnitude of interior relative movement in North China area, and others are the secondary tectonic active zones; ② The complete horizontal deformation in the North China area is not homogeneous nor successive; ③ The kinetic model of North China area might be (mantle dragging plus boundary coupling(. 展开更多
关键词 GPS measurement north china area active unit horizontal movement deformation mechanism
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Active blocks and their deformations derived from the velocity field in North China 被引量:1
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作者 黄立人 杨国华 王敏 《Acta Seismologica Sinica(English Edition)》 CSCD 2003年第1期79-91,共13页
Based on the horizontal movement velocities and their error estimations of 144 GPS stations in North China de-duced from the results obtained from multiple GPS measurements carried out in the period of 1992~2001, the ... Based on the horizontal movement velocities and their error estimations of 144 GPS stations in North China de-duced from the results obtained from multiple GPS measurements carried out in the period of 1992~2001, the horizontal deformation in the area is studied. The movements, entire deformations, local deformations, activity patterns and intensities along the boundary zones are derived. And then the risk of strong earthquake in the area is estimated. In the research, the horizontal displacement observations can be considered as the sum of three parts. The first part is the entire motion following Eurasian plate, which can be derived from NUVAL-IA model; the second part is the relative motions and deformations between the sub-tectonic blocks in the studied area, which can be derived from a set of displacement observations determined by the expanded QUAD method in the paper; the third part is the local deformations and errors in the sub-tectonic blocks, which can be described as the inhomoge-neous strains of the block. The method and results are introduced in detail in the paper. 展开更多
关键词 north china area horizontal movement application of QUAD method
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Hydrogeochemical characteristics of groundwater and pore-water and the paleoenvironmental evolution in the past 3.10 Ma in the Xiong’an New Area,North China 被引量:3
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作者 Kai Zhao Jing-xian Qi +6 位作者 Yi Chen Bai-heng Ma Li Yi Hua-ming Guo Xin-zhou Wang Lin-ying Wang Hai-tao Li 《China Geology》 2021年第3期476-486,共11页
The groundwater level has been continuously decreasing due to climate change and long-time overexploitation in the Xiong’an New Area,North China,which caused the enhanced mixing of groundwater in different aquifers a... The groundwater level has been continuously decreasing due to climate change and long-time overexploitation in the Xiong’an New Area,North China,which caused the enhanced mixing of groundwater in different aquifers and significant changes in regional groundwater chemistry characteristics.In this study,groundwater and sediment pore-water in drilling cores obtained from a 600 m borehole were investigated to evaluate hydrogeochemical processes in shallow and deep aquifers and paleo-environmental evolution in the past ca.3.10 Ma.Results showed that there was no obvious change overall in chemical composition along the direction of groundwater runoff,but different hydrochemical processes occurred in shallow and deep groundwater in the vertical direction.Shallow groundwater(<150 m)in the Xiong’an New Area was characterized by high salinity(TDS>1000 mg/L)and high concentrations of Mn and Fe,while deep groundwater had better water quality with lower salinity.The high TDS values mostly occurred in aquifers with depth<70 m and>500 m below land surface.Water isotopes showed that aquifer pore-water mostly originated from meteoric water under the influence of evaporation,and aquitard pore-water belonged to Paleo meteoric water.In addition,the evolution of the paleoclimate since 3.10 Ma BP was reconstructed,and four climate periods were determined by theδ18O profiles of pore-water and sporopollen records from sediments at different depths.It can be inferred that the Quaternary Pleistocene(0.78‒2.58 Ma BP)was dominated by the cold and dry climate of the glacial period,with three interglacial intervals of warm and humid climate.What’s more,this study demonstrates the possibilities of the applications of pore-water on the hydrogeochemical study and further supports the finding that pore-water could retain the feature of paleo-sedimentary water. 展开更多
关键词 GROUNDWATER PORE-WATER HYDROGEOCHEMISTRY Stable oxygen isotope Paleoclimate change Paleoenvironmental reconstruction Hydrogeological survey engineering Xiong’an New Area north china
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Genetic Relationship of the 1780-1760 Ma Dykes and the Coeval Volcanics in the Lvliang Area, North China 被引量:1
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作者 YANG Shuyan PENG Peng +2 位作者 Qin Zhaoyuan WANG Xinping WANG Chong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期133-134,共2页
The 1780-1760 Ma Taihang dyke swarm and the coeval Xiong’er volcanic province are the most widespread magmatic events occurring post the amalgamation of the two North China cratons.It has been debated whether
关键词 north china Genetic Relationship of the 1780-1760 Ma Dykes and the Coeval Volcanics in the Lvliang Area PB
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RESPONSE OF TRIASSIC SEQUENCE STRATIGRAPHY OF LOWER YANGTZE TO THE COLLISION BETWEEN THE YANGTZE PLATE AND THE NORTH CHINA PLATE 被引量:1
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作者 CHENG Rihui WANG Pujun LIU Wanzhu TANG Huafeng BAI Yunfeng KONG Qingying SONG Weihai 《Geotectonica et Metallogenia》 2005年第2期174-184,共11页
The characteristics of the Triassic sequences developed in the Lower Yangtze area display some great changes in both environment and climate. The change of environment was a transition from marine to continent via alt... The characteristics of the Triassic sequences developed in the Lower Yangtze area display some great changes in both environment and climate. The change of environment was a transition from marine to continent via alternating environments. The change of climate was a transition from tropic (torrid) to warm and wet climate via subtropic dry climate. The type variations of the sequences were from the marine sequences to the continental sequences, corresponding to the changes of environments and climates. Sequence 1 is a type II of sequence of mixed elastic and carbonate sediments; sequence 2 is a type I of sequence of carbonate platform; sequence 3 is a type I of sequence of carbonate tidal flat-salt lagoon, sequence 4 is a type iI of sequence of lacustrine within marine layers, and sequence 5 is a sequence of lacustrine-swamp. The development, distribution and preservation of those sequences reveal the tectonic controls and their changes in the background. The collision between the Yangtze plate and the North China plate was a great geological event in the geological history, but the timing of the collision is still disputed. However, the characteristics of Triassic sequence stratigraphy and sea level changes in the Lower Yangtze area responded to this collision. The collision started at the beginning of middle Triassic and the great regression in the Lower Yangtze area started 22Ma earlier than those in the world. The tectonic conditions occurred before and during the collision controlled the development of sequences and type changes. 展开更多
关键词 Yangtze plate north china plate Lower Yangtze area TRIASSIC sequence RESPONSE
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THE POSSIBILITIES AND REALITIES ON THE REMANAGEMENT OF DESERTIFIED LANDS IN THE TRANSITIONAL ZONE BETWEEN THE DRY-FARMING AREA AND THE GRAZING AREA IN NORTH CHINA
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作者 朱震达 刘恕 杨有林 《Chinese Geographical Science》 SCIE CSCD 1991年第1期32-43,共12页
The desertification process is rapidly developing at present and 61.5% of the land area in the zone are already desertified.Among the desertified lands, 26.9% are seriously desertified, 25% most seriously desertified ... The desertification process is rapidly developing at present and 61.5% of the land area in the zone are already desertified.Among the desertified lands, 26.9% are seriously desertified, 25% most seriously desertified and 47.4% are the lands where desertification is under way. They are caused by over-reclamation for farming, over-grazing, unreasonable collection of firewood,the destruction of vegetation and the misuse of water resources. Under the ecological environment in semi-arid zone,the degraded environment process possesses the ability of restoring to its original status as soon as the interruption of excessive human activities are eliminated. The fencing- and-self-cultivating method is an effective measure adopted universally in semi-arid zone to cure the desertified lands.The desertified lands can be readjusted and controlled easily if other controlling measures are supplemented. The fundamental ways to control desertification are to utilize rationally the resources, to readjust the existing 展开更多
关键词 desertified lands the transitional zone BETWEEN the dry-larming area and the GRAZinG area remanagement north china.
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Discussion on the dynamic mechanism of Great North China area based on the observed stress data
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作者 冯向东 魏东平 陈棋福 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2005年第1期1-11,124,共12页
Based on the constrained data from the observed stress orientation and the observed stress regime, the tectonic stress fields of the Great North China area has been simulated by using the pseudo-3D finite element meth... Based on the constrained data from the observed stress orientation and the observed stress regime, the tectonic stress fields of the Great North China area has been simulated by using the pseudo-3D finite element method. The results indicate that the stress fields in this area are basically controlled by the push forces coming from the Pacific Plate and from the Tibet Plateau, and the WNW-ward action from the Pacific Plate play a more important role in North China plain block. In addition to that, the stress field in this area is also partly formed by the extension action from the mantle upwelling in perpendicular at the basin margins. 展开更多
关键词 Great north china area stress regime finite element method dynamic simulation
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Mapping Spatial and Temporal Variations of Leaf Area Index for Winter Wheat in North China 被引量:13
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作者 YANG Peng WU Wen-bin +3 位作者 TANG Hua-jun ZHOU Qing-bo ZOU Jin-qiu ZHANG Li 《Agricultural Sciences in China》 CAS CSCD 2007年第12期1437-1443,共7页
Leaf area index (LAI) is an important parameter in a number of models related to ecosystem functioning, carbon budgets, climate, hydrology, and crop growth simulation. Mapping and monitoring the spatial and temporal... Leaf area index (LAI) is an important parameter in a number of models related to ecosystem functioning, carbon budgets, climate, hydrology, and crop growth simulation. Mapping and monitoring the spatial and temporal variations of LAI are necessary for understanding crop growth and development at regional level. In this study, the relationships between LAI of winter wheat and Landsat TM spectral vegetation indices (SVIs) were analyzed by using the curve estimation procedure in North China Plain. The series of LAI maps retrieved by the best regression model were used to assess the spatial and temporal variations of winter wheat LAI. The results indicated that the general relationships between LAI and SVIs were curvilinear, and that the exponential model gave a better fit than the linear model or other nonlinear models for most SVIs. The best regression model was constructed using an exponential model between surface-reflectance-derived difference vegetation index (DVI) and LAI, with the adjusted R2 (0.82) and the RMSE (0.77). The TM LAI maps retrieved from DVILAI model showed the significant spatial and temporal variations. The mean TM LAI value (30 m) for winter wheat of the study area increased from 1.29 (March 7, 2004) to 3.43 (April 8, 2004), with standard deviations of 0.22 and 1.17, respectively. In conclusion, spectral vegetation indices from multi-temporal Landsat TM images can be used to produce fine-resolution LAI maps for winter wheat in North China Plain. 展开更多
关键词 leaf area index (LAI) winter wheat spectral vegetation index (SVI) Landsat TM north china Plain
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Street Space in Traditional Settlements in Mountainous Area of North China 被引量:2
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作者 彭鹏 刘丽 《Journal of Landscape Research》 2010年第11期1-5,共5页
With mountainous area of North China as the research objective,the study analyzed street space in traditional settlements in mountainous area of North China from the perspective of form,structure and culture,hoping to... With mountainous area of North China as the research objective,the study analyzed street space in traditional settlements in mountainous area of North China from the perspective of form,structure and culture,hoping to find some methods and laws that could be served as the reference for the design of living environment in future. 展开更多
关键词 Mountainous area of north china TRADITIONAL SETTLEMENTS STREET SPACE
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Earthquake-controlling Processes of Detachment Zones in Eastern North China 被引量:1
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作者 SUNAiqun NIUShuyin +2 位作者 SHAOJi'an HOUQuanlin ZHANGJianzhen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期283-290,共8页
The basin-and-range area in eastern North China is known for frequent occurrence of earthquakes, their great magnitudes and heavy losses thereby incurred. Seismic studies in the past usually emphasized the intersectio... The basin-and-range area in eastern North China is known for frequent occurrence of earthquakes, their great magnitudes and heavy losses thereby incurred. Seismic studies in the past usually emphasized the intersections, inflexions and branches of the faults. However, the intensities of many great earthquakes in this area do not show linear distribution, and the epicenters are horizontally dispersed at certain depths instead of along the strike of faults. Based on the sub-mantle plume studies made by authors in the past decade, it is thought that there exists an uplifted sub-mantle plume under the fault depression area in North China. The uplifting and intrusion of mantle materials caused the upper crust to be faulted, while low-velocity and high-velocity layers are alternatively distributed in the middle crust under the influence of the mantle and the lower crust. The middle and lower crust materials were detached from the top of the sub-mantle plume to the surroundings while the sub-mantle plume materials were detached outward. When the detached middle and lower crust come to the boundary of fault basins in the upper crust, they will be obstructed by the orogenic zone and the detachment will go slower. The shearing between them will cause the stress to accumulate and release alternatively, so that earthquakes occurred frequently in the areas of sub-mantle plume and its surroundings. 展开更多
关键词 sub-mantle plume detachment belt earthquake-controlling structure low-velocity and high-conductivity zones north china basin-and range area
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Optimizing groundwater recharge plan in North China Plain to repair shallow groundwater depression zone, China 被引量:2
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作者 Rui-fang Meng Hui-feng Yang +4 位作者 Xi-lin Bao Bu-yun Xu Hua Bai Jin-cheng Li Ze-xin Liang 《Journal of Groundwater Science and Engineering》 2023年第2期133-145,共13页
The North China Plain is one of the main grain producing areas in China. However, overexploitation has long been unsustainable since the water supply is mainly from groundwater. Since 2014,the South-to-North Water Div... The North China Plain is one of the main grain producing areas in China. However, overexploitation has long been unsustainable since the water supply is mainly from groundwater. Since 2014,the South-to-North Water Diversion Project's central route has been charted to the integrated management of water supply and over-exploitation, which has alleviated the problem to a certain extent. Although the Ministry of Water Resources has made many efforts on groundwater recharge since 2018 most of which have been successful, the recharge has not yet been sufficiently focused on the repair of shallow groundwater depression zones. It still needs further optimization. This paper discusses this particular issue,proposes optimized recharge plan and provides the following recommendations:(1) Seven priority target areas are selected for groundwater recharge in alluvial and proluvial fans in the piedmont plain, and the storage capacity is estimated to be 181.00×10~8 m~3;(2) A recharge of 31.18×10~8 m~3/a is required by 2035 to achieve the repair target;(3) It is proposed to increase the recharge of Hutuo River, Dasha River and Tanghe River to 19.00×10~8 m~3/a and to rehabilitate Gaoliqing-Ningbailong Depression Zone;increase the recharge of Fuyang River, Zhanghe River and Anyang River to 7.05×10~8 m~3/a and rehabilitate Handan Feixiang-Guangping Depression Zone;increase the recharge of Luanhe River by 0.56×10~8 m~3/a and restore Tanghai Depression Zone and Luanan-Leting Depression Zone;moderately reduce the amount of water recharged to North Canal and Yongding River to prevent excessive rebound of groundwater;(4) Recharge through well is implemented on a pilot basis in areas of severe urban ground subsidence and coastal saltwater intrusion;(5) An early warning mechanism for groundwater quality risks in recharge areas is established to ensure the safety. The numerical groundwater flow model also proves reasonable groundwater level restoration in the depression zones by 2035. 展开更多
关键词 north china Plain Groundwater recharge Groundwater depression zone Recharge target areas Storage capacity Recharge source Recharge effectiveness
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Analysis on Variations of the Temperature and Precipitation in North Slope Area of the Western Tianshan in Recent 50 Years
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作者 YAO Fu-long,LI Hai-bing College of Chemistry and Biological Sciences,Yili Normal University,Yining 835000,China 《Meteorological and Environmental Research》 CAS 2011年第11期17-22,共6页
[Objective] The research aimed to analyze variation characteristics of the temperature and precipitation in north slope area of the Western Tianshan in recent 50 years.[Method] According to temperature and rainfall da... [Objective] The research aimed to analyze variation characteristics of the temperature and precipitation in north slope area of the Western Tianshan in recent 50 years.[Method] According to temperature and rainfall data from 1961 to 2010 at three meteorological stations in north slope area of the Western Tianshan,climate change in the zone in recent 50 years was analyzed by using linear trend analysis method and 5-year sliding average method.[Result] The temperature in north slope area of the Western Tianshan showed significant warming trend.The annual average temperature significantly increased at 0.3 ℃/10 a in recent 50 years.But rise rates of the temperature in different seasons were different:autumn> winter> spring> summer.The annual rainfall in north slope area of the Western Tianshan in recent 50 years overall presented relative increase trend.Seen from annual rainfall,it significantly increased at 16.9 mm/10 a.Seen from seasonal rainfall,except in autumn,rainfalls in other three seasons in the past 50 years all showed significant increase trends,with amplitude of 3.2-11.2 mm/10 a.The largest increase amplitude was in summer.After a small precipitation peak in the 1980s,autumn rainfall slightly declined in the past 20 years.[Conclusion] The climate in north slope area of the Western Tianshan become warm and wet. 展开更多
关键词 Climate change TEMPERATURE PRECIPITATION north slope area of the Western Tianshan china
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Slope runoff study in situ using rainfall simulator in mountainous area of North China
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作者 于静洁 杨聪 +4 位作者 刘昌明 宋献方 胡珊珊 李发东 唐常源 《Journal of Geographical Sciences》 SCIE CSCD 2009年第4期461-470,共10页
Simulated rainfall is a valid tool to examine the runoff generation on the slope.13 simulated rainfall experiments with different rainfall intensities and durations are completed in a 5 m ×10 m experimental plot ... Simulated rainfall is a valid tool to examine the runoff generation on the slope.13 simulated rainfall experiments with different rainfall intensities and durations are completed in a 5 m ×10 m experimental plot in mountainous area of North China.Simultaneously,rainfall,surface runoff,soil-layer flow,mantel-layer flow and soil moisture are monitored respectively.From the results,it is found that the hydrographs in all layers have the characteristics of rapid rise and fall.The recessions of surface flow and soil-layer flow are much faster than that of mantel-layer flow.Surface flow,the main contributor,makes up more than 60% of the total runoff in the study area.It even exceeds 90% in the cases of high intensity rainfall events.Runoff coefficient(ratio of total runoff to rainfall amount) is mainly influenced by rainfall amount,rainfall intensity and antecedent soil moisture,and the relationship can be well expressed by a multiple linear regression function α = 0.002P + 0.182i + 4.88Wa-0.821.The relation between the rainfall intensity and the lag time of three flows(surface runoff,soil-layer flow and mantel-layer flow) is shown to be exponential.Then,the result also shows that the recession constant is 0.75 for surface runoff,is 0.94 for soil-layer and mantel-layer flow in this area.In this study area,the dominant infiltration excess runoff is simulated by Horton model.About 0.10 mm/min percolation is observed under the condition of different rainfall intensities,therefore the value is regarded as the steady infiltration rate of the study area. 展开更多
关键词 simulated rainfall slope plot runoff generation process mountainous area of north china
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The Human Rights Legislation Practices of the Communist Party of China During the War of Liberation
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作者 化国宇 吕圣旺 XU Chao(译) 《The Journal of Human Rights》 2021年第3期364-373,共10页
During the War of Liberation,the liberated areas,under the leadership of the Communist Party of China,kept deepening and developing the concepts and ideas of protecting human rights,promulgated a series of human right... During the War of Liberation,the liberated areas,under the leadership of the Communist Party of China,kept deepening and developing the concepts and ideas of protecting human rights,promulgated a series of human rights laws and related administrative programs,and put them into practice.The contents included not only the political rights of citizens but also their economic,social,and cultural rights,with emphasis on the protection of the rights to subsistence and development.The human rights legislation in the liberated areas has a wartime and class-based nature due to its social environment.It reflects the transition of the Communist Party of China from a revolutionary party to a ruling party on the historical stage.It played an important role in directing,advancing,and promoting the progress of democracy and the rule of law at that time and accumulated experience for the human rights legislation after the founding of the People’s Republic of China.History proves that the Communist Party of China has always been a political party dedicated to fighting for the human rights of the Chinese people,and only the Communist Party of China can lead China’s human rights development to a deeper level. 展开更多
关键词 the Communist Party of china human rights legislation in the liberated areas Constitutional Principles of the Shaanxi-Gansu-Ningxia Border Region Outline of china’s Land Law
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Exploration and development of continental tight oil in China 被引量:2
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作者 HU Suyun ZHU Rukai +3 位作者 WU Songtao BAI Bin YANG Zhi CUI Jingwei 《Petroleum Exploration and Development》 2018年第4期790-802,共13页
Based on the investigation of tight oil exploration and development in North America, the successful cases of tight oil exploration and development in North America are summarized. The geological differences between c... Based on the investigation of tight oil exploration and development in North America, the successful cases of tight oil exploration and development in North America are summarized. The geological differences between continental tight oil in China and marine tight oil in North America is analyzed to explore the technical strategies for the industrial development of continental tight oil in China. The experiences of large-scale exploration and profitable development of tight oil in North America can be taken as references from the following 6 perspectives, namely exploring new profitable strata in mature exploration areas, strengthening the economic evaluation of sweet spots and focusing on the investment for high-profitability sweet spots, optimizing the producing of tight oil reserves by means of repetitive fracturing and 3 D fracturing, optimizing drilling and completion technologies to reduce the cost, adopting commodity hedging to ensure the sustainable profit, and strengthening other resources exploration to improve the profit of whole project. In light of the high abundance of tight oil in China, we can draw on successful experience from North America, four suggestions are proposed in sight of the geological setting of China's lacustrine tight oil:(1) Evaluating the potential of tight oil resources and optimizing the strategic area for tight oil exploration;(2) selecting "sweet spot zone" and "sweet spot interval" accurately for precise and high efficient development;(3) adopting advanced tight oil fracturing technology to realize economic development;(4) innovating management system to promote the large-scale profitable development of tight oil. 展开更多
关键词 CONTinENTAL TIGHT OIL sweet-spot area sweet-spot interval profitable exploration and development china north AMERICA
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Analysis of the influence of collection purification filtration system of channel upon groundwater quality about freeway
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作者 QIN Ren-jie ZHANG Bao-jing LIU Zhao-hui 《Journal of Environmental Science and Engineering》 2009年第7期1-5,共5页
At present, it is usually used the method that elevating the height of embankment to design passages of freeway to avoid transverse traffic disturbance in plain areas of China. But when design low embankment, it is di... At present, it is usually used the method that elevating the height of embankment to design passages of freeway to avoid transverse traffic disturbance in plain areas of China. But when design low embankment, it is difficulty for drainage or setting passages and culverts. Hengshui to Darning freeway in Hebei provence (Heng-Da freeway) is one section of Dalian to Guangzhnu freeway. This paper analyzes the characteristic of climate, geology, hydrology and low water table, good permeability stratum soil and its little and mass rain fall and deep drinking water well in the plain areas of North China when design low embankment of Heng-Da freeway, puts forward the drainage methods of water collecting filtration system to solve the drainage problem of passages and culverts, aiming at the type and the measures of the pollution on the surface, the channel collection purification infiltration system of highway uses the single composite technology of aerobic and oxygen to digest - precipitation-absorption of artificial materials percolation of soil to deal with the pollution of the rain on the road (the composite technology use the vermiculite as the material of infiltration), which be controlled in the drinking range of the water standard. It not only efficiently solved the problem of water collected in the channel, but also supplied the groundwater. It has reached the environment-friendly road construction purpose of the sustainable development of highway construction, "environment friendly" and "resource conservation". 展开更多
关键词 plain areas of north china FREEWAY low embankment VERMICULITE collection purification infiltration system
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Toward a Security Community in Asia? The Limits of Constructivism, Developmental Statism, Liberalism, and Realism
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作者 Sorpong Peou 《International Relations and Diplomacy》 2022年第1期1-24,共24页
This article asks whether a regional security community has emerged in Asia with the potential to grow mature and seeks to make a contribution to the ongoing debate on this controversial topic.It advances the argument... This article asks whether a regional security community has emerged in Asia with the potential to grow mature and seeks to make a contribution to the ongoing debate on this controversial topic.It advances the argument that states in this broad region are far from being able to develop a security community for reasons different from those provided by political realists,developmental statists,liberals,and constructivists(social,discursive,and emancipationist).The role of Association of Southeast Asia(ASEAN)and that of China provide excellent test cases for the theoretical proposition that the building of a successful regional security community requires at least two necessary conditions:liberal democracy and regional democratic leadership,which remain absent in Asia. 展开更多
关键词 regional security community ASIA ASEAN china European Union north America CONSTRUCTIVISM LIBERALISM political realism liberal democracy regional democratic leadership
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Seasonal Variation and Meteorological Control of CO_2 Flux in a Hilly Plantation in the Mountain Areas of North China 被引量:4
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作者 黄辉 张劲松 +3 位作者 孟平 伏玉玲 郑宁 高峻 《Acta meteorologica Sinica》 SCIE 2011年第2期238-248,共11页
The carbon cycle of terrestrial ecosystems is an important scientific issue in global climate change research.Plantation forest plays an important role in terrestrial carbon budget in China.In this study,eddy covarian... The carbon cycle of terrestrial ecosystems is an important scientific issue in global climate change research.Plantation forest plays an important role in terrestrial carbon budget in China.In this study,eddy covariance flux data measured at Xiaolangdi forest ecosystem research station(XLD) in 2007 and 2008 are used to analyze the seasonal variation and meteorological control of CO2 flux in a 30-yr-old mixed plantation.The plantation forest mainly consists of Quercus variabilis,Platycladus orientalis,and Robinia pseudoacacia.The results show that the seasonal variations of net ecosystem exchange of CO2(NEE),gross primary production(GPP),and ecosystem respiration(Re) display single-peak curves.The maximum of carbon sequestration appears during May and June each year.The relative contribution of carbon release from ecosystem respiration to GPP varied slightly between 2007 and 2008.The relationship between NEE and photosynthetic active radiation(Qp) accords with the rectangular hyperbola model on diurnal scale,and shows a good linear correlation on monthly scale.The ecosystem photosynthetic parameters:the maximum photosynthetic rate(Pmax),the ecosystem photosynthetic photonyield(α),and the daytime ecosystem respiration(Rd) exhibit seasonal variations.Pmax reaches the maximum in August each year,with small interannual difference.The interannual differences of α and Rd are obvious,which is attributed to the changes of meteorological factors,such as solar radiation,vapor pressure deficit(D),precipitation,etc.Parameters Re,GPP,and NEP(net ecosystem production) have obvious exponential relations with temperature on monthly scale.There is a hysteresis in the response of GPP and NEP to temperature,i.e.,the carbon sequestration is not the maximum when the temperature reaches the peak value.The Q10 values were 1.37 and 1.45 in 2007 and 2008,respectively.On monthly scale,Re,GPP,and NEE increase as D increases,but rise slowly and even decrease when D is higher than 1.5 kPa. 展开更多
关键词 hilly area of north china PLANTATION eddy covariance CO2 flux meteorological factors
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Change of winter wheat planting area and its impacts on groundwater depletion in the North China Plain 被引量:9
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作者 WU Xifang QI Yongqing +3 位作者 SHEN Yanjun YANG Wei ZHANG Yucui KONDOH Akihiko 《Journal of Geographical Sciences》 SCIE CSCD 2019年第6期891-908,共18页
The North China Plain is one of the most water-stressed areas in China. Irrigation of winter wheat mainly utilizes groundwater resources, which has resulted in severe environmental problems. Accurate estimation of cro... The North China Plain is one of the most water-stressed areas in China. Irrigation of winter wheat mainly utilizes groundwater resources, which has resulted in severe environmental problems. Accurate estimation of crop water consumption and net irrigation water consumption is crucial to guarantee the management of agricultural water resources. An actual crop evapotranspiration(ET) estimation model was proposed, by combining FAO Penman-Monteith method with remote sensing data. The planting area of winter wheat has a significant impact on water consumption; therefore, the planting area was also retrieved. The estimated ET showed good agreement with field-observed ET at four stations. The average relative bias and root mean square error(RMSE) for ET estimation were –2.2% and 25.5 mm, respectively. The results showed the planting area and water consumption of winter wheat had a decreasing trend in the Northern Hebei Plain(N-HBP) and Southern Hebei Plain(S-HBP). Moreover, in these two regions, there was a significant negative correlation between accumulated net irrigation water consumption and groundwater table. The total net irrigation water consumption in the N-HBP and S-HBP accounted for 12.9×10~9 m^3 and 31.9×10~9 m^3 during 2001–2016, respectively. Before and after 2001, the decline rate of groundwater table had a decreasing trend, as did the planting area of winter wheat in the N-HBP and S-HBP. The decrease of winter wheat planting area alleviated the decline of groundwater table in these two regions while the total net irrigation water consumption was both up to 28.5×10~9 m^3 during 2001–2016 in the Northwestern Shandong Plain(NW-SDP) and Northern Henan Plain(N-HNP). In these two regions, there was no significant correlation between accumulated net irrigation water consumption and groundwater table. The Yellow River was able to supply irrigation and the groundwater table had no significant declining trend. 展开更多
关键词 north china PLAin PLANTinG area WinTER wheat remote sensing net IRRIGATION water consumption
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