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Hebei Museum
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作者 MENG JIAXIN 《China Today》 2025年第8期76-79,共4页
The rich historical and cultural legacy of Hebei Province is indispensable to Chinese civilization.Much of it has been well preserved in the Hebei Museum,which provides a window into Hebei’s vibrant heritage.
关键词 Chinese Civilization hebei Museum Historical Legacy PRESERVATION Cultural Heritage historical cultural legacy
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2025 Gaoyang Textile&Apparel Event:Boosting supply chain&industry upgrade in Beijing–Tianjin–Hebei region
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作者 Qiu Shuchen 《China Textile》 2025年第3期32-33,共2页
On May 21st,the launch ceremony of the 2025 Textile and Clothing"Optimization of Supply and Upgrade"event was held in Gaoyang,Hebei Province.The theme of the event is to promote the coordinated development a... On May 21st,the launch ceremony of the 2025 Textile and Clothing"Optimization of Supply and Upgrade"event was held in Gaoyang,Hebei Province.The theme of the event is to promote the coordinated development and supply-demand docking of the textile and clothing industry in the Beijing–Tianjin–Hebei Region.Representatives from the textile and clothing industries gathered in Gaoyang to discuss the coordinated development of regional industries.The Ministry of Industry and Information Technology,Industry Associations,and leaders of the three local governments jointly announced the official launch of the national industrial upgrading action. 展开更多
关键词 beijing tianjin hebei region industrial upgrading action industry upgrade supply chain TEXTILE coordinated development clothing supply demand docking
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Estimation of Soil Organic Carbon Stocks Utilizing Machine Learning Algorithms and Multi-source Geospatial Data in Coastal Wetlands of Tianjin and Hebei,China
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作者 YANG Rui LIU Mingyue +10 位作者 ZHANG Yongbin MAN Weidong TONG Jingfen LIU Dong ZHANG Qingwen KOU Caiyao LI Xiang LIU Yahui TIAN Di YIN Xuan HE Jiannan 《Chinese Geographical Science》 2025年第4期707-721,I0003,共16页
Coastal wetlands are crucial for the‘blue carbon sink’,significantly contributing to regulating climate change.This study util-ized 160 soil samples,35 remote sensing features,and 5 geo-climatic data to accurately e... Coastal wetlands are crucial for the‘blue carbon sink’,significantly contributing to regulating climate change.This study util-ized 160 soil samples,35 remote sensing features,and 5 geo-climatic data to accurately estimate the soil organic carbon stocks(SOCS)in the coastal wetlands of Tianjin and Hebei,China.To reduce data redundancy,simplify model complexity,and improve model inter-pretability,Pearson correlation analysis(PsCA),Boruta,and recursive feature elimination(RFE)were employed to optimize features.Combined with the optimized features,the soil organic carbon density(SOCD)prediction model was constructed by using multivariate adaptive regression splines(MARS),extreme gradient boosting(XGBoost),and random forest(RF)algorithms and applied to predict the spatial distribution of SOCD and estimate the SOCS of different wetland types in 2020.The results show that:1)different feature combinations have a significant influence on the model performance.Better prediction performance was attained by building a model using RFE-based feature combinations.RF has the best prediction accuracy(R^(2)=0.587,RMSE=0.798 kg/m^(2),MAE=0.660 kg/m^(2)).2)Optical features are more important than radar and geo-climatic features in the MARS,XGBoost,and RF algorithms.3)The size of SOCS is related to SOCD and the area of each wetland type,aquaculture pond has the highest SOCS,followed by marsh,salt pan,mud-flat,and sand shore. 展开更多
关键词 soil organic carbon stocks(SOCS) soil organic carbon density(SOCD) multivariate adaptive regression spline(MARS) extreme gradient boosting(XGBoost) random forest(RF) residual kriging(RK) feature optimization coastal wetlands Tianjin and hebei China
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Analysis on the Distribution Characteristics of Atmospheric Aerosol Particles in Hebei Area in the Cloudy Day Condition 被引量:3
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作者 孙玉稳 孙霞 +1 位作者 姜岩 李云川 《Meteorological and Environmental Research》 CAS 2010年第7期9-11,共3页
By using the probe data of two sorties airplane in the middle and southern parts of Hebei Province in 2007 spring,the characteristics of atmospheric aerosol particles concentration and size distribution in the area in... By using the probe data of two sorties airplane in the middle and southern parts of Hebei Province in 2007 spring,the characteristics of atmospheric aerosol particles concentration and size distribution in the area in the cloudy day situation were analyzed.The results showed that the overall trend of aerosol particles concentration in the weather systems which included the south branch trough and North China low vortex was the decrease as the height increased.However,if the cirrostratus was in the high altitude,it increased as the height increased.In the bottom of inversion layer,there existed the obvious accumulation of aerosol and cloud droplet.Affected by the complex weather systems,the aerosol particle size distribution presented the multi-peak type for the disturbance of updraft or turbulence. 展开更多
关键词 hebei Atmospheric aerosol Particle size distribution OBSERVATION China
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Analysis on Vapour Field for the Drought Causes in Beijing,Tianjin and Hebei Districts in Recent Years 被引量:5
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作者 杨文霞 李宏宇 +1 位作者 李宗涛 房彬 《Agricultural Science & Technology》 CAS 2010年第1期117-121,共5页
The monthly variation,temporal-spatial distribution,transportation characteristics of vapour field at middle and lower atmosphere and their effects on drought in Beijing,Tianjin and Hebei districts were studied,which ... The monthly variation,temporal-spatial distribution,transportation characteristics of vapour field at middle and lower atmosphere and their effects on drought in Beijing,Tianjin and Hebei districts were studied,which have a guiding significance on predicting climate and arranging agricultural production in the district. 展开更多
关键词 BEIJING Tianjin and hebei district DROUGHT Vapour field
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Discussion on the Prevention and Control Countermeasures of Sudden Disasters on Protected Vegetable in Hebei Province 被引量:1
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作者 刘云 梁玉芹 +1 位作者 王灵敏 宋炳彦 《Agricultural Science & Technology》 CAS 2016年第3期511-515,共5页
Protected vegetable production made the traditional agriculture gradually get rid of the shackles of nature, broke the seasonal traditional agriculture and realized the anti season list of agricultural products. While... Protected vegetable production made the traditional agriculture gradually get rid of the shackles of nature, broke the seasonal traditional agriculture and realized the anti season list of agricultural products. While protected vegetables often encountered sudden disasters in production and were restricted with the conditions of low temperature and weak light. Aimed at the sudden disasters of protected vegetable production in Hebei Province,the countermeasures for disaster prevention and control were put forward from the aspects of variety selection, seedling treatment technology,grafting technique,cultivation and management,flower and fruit retention technology,application of exogenous substance,rational fertilization,transgenic technology and so on,in order to reduce production risks and cut loss,realize that protected vegetable production is safe,good-quality and efficient. 展开更多
关键词 hebei Province Protected vegetable Sudden disasters Prevention and control countermeasures
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Breeding of Hybrid Hebei Cashmere Goat
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作者 王振来 赵德明 《Animal Husbandry and Feed Science》 CAS 2009年第3期1-3,14,共4页
[Objective] To improve the performance of Hebei cashmere goats and thus promote the development of cashmere industry. [Method] Through grading hybridization, the F2 generation was obtained using Liaoning cashmere goat... [Objective] To improve the performance of Hebei cashmere goats and thus promote the development of cashmere industry. [Method] Through grading hybridization, the F2 generation was obtained using Liaoning cashmere goats as male parents and local cashmere goats as female parents. Then fixed cross was performed. After selection, the body size indexes, weight and cashmere yield were determined. The quality of cash mere, lambing rate, and net cashmere rate were also analyzed. [ Result] Compared with the local cashmere goats, the hybrid cashmere goats had robust physique and good body size indexes; the weight and cashmere yield increased significantly; cashmere fiber was longer significantly; the lambing rate and net cashmere rate were improved. [ Conclusion] After breeding, the cashmere goats have good quality and high yield of cashmere, and their performance is significantly improved. 展开更多
关键词 hebei cashmere goat Hybridization and breeding
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Magmatic Event at the End of the Archean in Eastern Hebei Province and Its Geological Implication 被引量:95
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作者 GENG Yuansheng LIU Fulai YANG Chonghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第6期819-833,共15页
By using the SHRIMP U-Pb and single zircon stepwise evaporation methods, the authors have obtained some results for granitoids from eastern Hebei Province. The Yuhuzhai hyperthene tonalitic granite was formed 2550 Ma ... By using the SHRIMP U-Pb and single zircon stepwise evaporation methods, the authors have obtained some results for granitoids from eastern Hebei Province. The Yuhuzhai hyperthene tonalitic granite was formed 2550 Ma ago, the Qingyangshu gabbroic gneiss 2536 Ma, the Yinmahe granodioritic gneiss near Lücao, Lulong County, 2533 Ma, the gabbro-dioritic gneiss near Longwan, Qianxi County, 2518-2515 Ma, the Qiuhuayu trondjemitic gneiss at Zunhua 2515 Ma, the Xiaoguanzhuang tonalitic gneiss at Zunhua 2495 Ma, and the Cuizhangzi gneiss in Qianxi County 2492 Ma. These geochronilogical data demonstrate that, though diverse in composition, type and origin, the granitic gneisses in eastern Hebei Province were emplaced and crystallized in a rather short period of magmatic activity. The formation of such a great amount of gneisses in this small time gap suggests that it was a critical crust accretion stage at the end of Neoarchean. The fact that granitoids of various types occurred at the same time implies a large-scale underplating (mantle plume) activity, which was then responsible for the crust accretion. 展开更多
关键词 ORTHOGNEISS magmatic event NEOARCHEAN zircon age eastern hebei Province
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A New Enantiornitine Bird with Four Long Rectrices from the Early Cretaceous of Northern Hebei,China 被引量:12
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作者 ZHENG Xiaoting ZHANG Zihui HOU Lianhai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第5期703-708,共6页
Paraprotopteryx gracilis, a new enantiornithine bird from the Early Cretaceous Yixian Formation in Fengning, northern Hebei Province is erected, based on the following characters: Yshaped furcula with a long hypoclei... Paraprotopteryx gracilis, a new enantiornithine bird from the Early Cretaceous Yixian Formation in Fengning, northern Hebei Province is erected, based on the following characters: Yshaped furcula with a long hypocleidum and a much narrow interclavicular angle, and the morphology of the sternum are different from other enantiornithines. Additionally, alular digit bearing the biggest manual claw extends distally to the distal end of the major metacarpal; the minor metacarpal is slender than the major metacarpal. Carpometacarpus only fused proximally; astragalus and calcaneum partially fused to one another but unfused to the tibia. This is the first record of Mesozoic birds in having four long rectrices, which may represent morphologically a secondary sexual character, an intermediate stage from elongated scale to branched feather, and possess functional advantage in supplementing the lifting surface to compensate the unskilled flight. 展开更多
关键词 Early Cretaceous Paraprotopteryx gracilis enantiornithine rectrices Fengning hebei Province
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Impact of the shrinking winter wheat sown area on agricultural water consumption in the Hebei Plain 被引量:18
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作者 WANG Xue LI Xiubin XIN Liangjie 《Journal of Geographical Sciences》 SCIE CSCD 2014年第2期313-330,共18页
This study firstly analyzed the shrinkage of winter wheat and the changes of crop- ping systems in the Hebei Plain from 1998 to 2010 based on the agricultural statistic data of 11 cities and meteorological data, inclu... This study firstly analyzed the shrinkage of winter wheat and the changes of crop- ping systems in the Hebei Plain from 1998 to 2010 based on the agricultural statistic data of 11 cities and meteorological data, including daily temperature, precipitation, water vapor, wind speed and minimum relative humidity data from 22 meteorological stations, and then calcu- lated the water deficit and irrigation water resources required by different cropping systems, as well as the irrigation water resources conserved as a result of cropping system changes, using crop coefficient method and every ten-day effective precipitation estimation method. The results are as follows. 1) The sown areas of winter wheat in the 11 cities in the Hebei Plain all shrunk during the study period. The shrinkage rate was 16.07% and the total shrinkage area amounted to 49.62×10^4 ha. The shrinkage was most serious in the Bei- jing-Tianjin-Tangshan metropolitan agglomerate, with a shrinkage rate of 47.23%. 2) The precipitation fill rate of winter wheat was only 20%-30%, while those of spring maize and summer maize both exceeded 50%. The irrigation water resources demanded by the winter wheat-summer maize double cropping system ranged from 400 mm to 530 mm, while those demanded by the spring maize single cropping system ranged only from 160 mm to 210 ram. 3) The water resources conserved as a result of the winter wheat sown area shrinkage during the study period were about 15.96×10^8 m^3/a, accounting for 27.85% of those provided for Beijing, Tianjin and Hebei by the first phase of the Mid-Route of the South-to-North Water Diversion Project. 展开更多
关键词 irrigation water resources winter wheat sown area shrinkage crop water consumption hebei Plain
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Analysis of air quality characteristics of Beijing–Tianjin–Hebei and its surrounding air pollution transport channel cities in China 被引量:18
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作者 Cuicui Xiao Miao Chang +2 位作者 Peikun Guo Meifeng Gu Yang Li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第1期213-227,共15页
Beijing–Tianjin–Hebei(BTH)and its surrounding areas are very important to air pollution control in China.To analyze the characteristics of BTH and its surrounding areas of China,we collected 5,641,440 air quality da... Beijing–Tianjin–Hebei(BTH)and its surrounding areas are very important to air pollution control in China.To analyze the characteristics of BTH and its surrounding areas of China,we collected 5,641,440 air quality data from 161 air monitoring stations and 37,123,000 continuous monitoring data from air polluting enterprises in BTH and surrounding cities to establish an indicator system for urban air quality portraits.The results showed that particulate matter with aerodynamic diameters of<2.5μm(PM2.5),particulate matter with aerodynamic diameters of<10μm(PM10)and SO2 improved significantly in 31 cities from2015 to 2018,but ozone deteriorated.Air quality in BTH and the surrounding areas showed obvious seasonal characteristics,among which PM2.5,PM10,SO2,and NO2 showed a"U"type distribution from January to December,while O3 had an"inverted U"distribution.The hourly changes in air quality revealed that peaks of PM2.5,PM10 and NO2 appeared from 8:00 to 10:00,while those for O3 appeared at 15:00–16:00.The exposure characteristics of the 31 cities showed that six districts in Beijing had the highest air quality population exposure,and that exposure levels in Zhengzhou,Puyang,Anyang,Jincheng were higher than the average of the 31 investigated cities.Additionally,multiple linear regression revealed a negative correlation between meteorological factors(especially wind and precipitation)and air quality,while a positive correlation existed between industrial pollution emissions and air quality in most of BTH and its surrounding cities. 展开更多
关键词 Beijing–Tianjin–hebei Air quality population exposure Seasonal index Hourly change Industrial pollution source emission Meteorology factors
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A New Ceratopsian from the Upper Jurassic Houcheng Formation of Hebei, China 被引量:9
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作者 ZHAO Xijin CHENG Zhengwu +1 位作者 XU Xing Peter J. MAKOVICKY 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第4期467-473,共7页
A new ceratopsian taxon Xuanhuaceratops niei gen. et sp. nov. is erected based on four fragmentary specimens collected from the Late Jurassic Houcheng Formation, Hebei Province, China. Xuanhuaceratops shares a number ... A new ceratopsian taxon Xuanhuaceratops niei gen. et sp. nov. is erected based on four fragmentary specimens collected from the Late Jurassic Houcheng Formation, Hebei Province, China. Xuanhuaceratops shares a number of derived features with, and is closely related to, another probable Late Juarassic ceratopsian Chaoyangsaurus youngi, from which it differs in only possessing a single premaxlllary tooth as well as in details of quadrate and scapular morphology. We hypothesize that these two taxa represent a primitive lineage of Ceratopsia that is basal to the psittacosauridneoceratopsian diversity, and propose the name Chaoyangsauridae for it. 展开更多
关键词 Houcheng Formation JURASSIC hebei Chaoyangsauridae CERATOPSIA
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Estimated cancer incidence and mortality in Hebei province,2012 被引量:8
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作者 Yutong He Di Liang +5 位作者 Daojuan Li Jingbo Zhai Junqing Zhu Jing Jin Denggui Wen Baoen Shan 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2016年第3期286-300,共15页
Objective: This study estimates the numbers of new cancer cases and cancer deaths in Hebei province using incidence and mortality data from 9 population-based cancer registries in 2012. Methods: The data of new diag... Objective: This study estimates the numbers of new cancer cases and cancer deaths in Hebei province using incidence and mortality data from 9 population-based cancer registries in 2012. Methods: The data of new diagnosed cancer cases and cancer deaths in 2012 were collected from 9 population-based cancer registries of Hebei province in 2015. All the data met the National Central Cancer Registry of China (NCCR) criteria of data quality. The pooled data analysis was stratified by areas (urban/ rural), gender, age group (0, 1-4, 5-9, 10-14 85+) and cancer type. New cancer cases and deaths in Hebei province were estimated using age-specific rates and corresponding provincial population in 2012. The 10 most common cancers in different groups and the cumulative rates were calculated. Chinese population census in 2000 and Segi's population were used for age-standardized incidence/mortality rates. Results: All cancer registries covered 4,986,847 populations, 6.84% of Hebei provincial population (2,098,547 in urban and 2,888,300 in rural areas). The percentage of cases morphologically verified (MV%) and death certificate-only cases (DCO%) were 76.40% and 4.72%, respectively. The mortality to incidence rate ratio (M/I) was 0.64. In 2012, it is estimated that there were about 187,900 new diagnosed cancer cases and 119,800 cancer deaths in Hebei province. The incidence rate of cancer was 258.12/100,000 (275.75/100,000 in males, 239.78/100,000 in females), and the age-standardized incidence rates by Chinese standard population (ASIRC) and by world standard population (ASIRW) were 210.65/100,000 and 208.50/100,000, with the cumulative incidence rates (0-74 years old) of 24.46%. The cancer incidence and ASIRC were 256.99/100,000 and 211.32/100,000 in urban areas and 258.94/100,000 and 209.99/100,000 in rural areas, respectively. The cancer mortality rate was 164.63/100,000 (201.85/100,000 in males, 125.92/100,000 in females). Age- standardized mortality rates by Chinese standard population (ASMRC) and by world standard population (ASMRW) were 137.30/100,000 and 137.39/100,000 with the cumulative mortality rate (0-74 years old) of 14.58%, respectively. The cancer mortality rate in rural areas (167.16/100,000) was higher than that in urban areas (161.16/100,000). The most common cancers were lung cancer, stomach cancer, breast cancer, esophageal cancer, liver cancer and colorectal cancer, which accounted for 72.31% of all cancer cases. Lung cancer, stomach cancer, liver cancer, esophageal cancer and colorectal cancer were the major causes of cancer death in Hebei province, which accounted for 75.24% of all cancer deaths. The cancer spectrum differs between urban and rural, males and females in both incidence and mortality rates. Conclusions: The most common cancers were lung cancer, stomach cancer, esophageal cancer, breast cancer, liver cancer and eolorectal cancer in Hebei province. 展开更多
关键词 Cancer registry CANCER INCIDENCE MORTALITY hebei province
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Vegetation NPP Distribution Based on MODIS Data and CASA Model——A Case Study of Northern Hebei Province 被引量:20
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作者 YUAN Jinguo NIU Zheng WANG Chenli 《Chinese Geographical Science》 SCIE CSCD 2006年第4期334-341,共8页
Net Primary Productivity (NPP) is one of the important biophysical variables of vegetation activity, and it plays an important role in studying global carbon cycle, carbon source and sink of ecosystem, and spatial a... Net Primary Productivity (NPP) is one of the important biophysical variables of vegetation activity, and it plays an important role in studying global carbon cycle, carbon source and sink of ecosystem, and spatial and temporal distribution of CO2. Remote sensing can provide broad view quickly, timely and multi-temporally, which makes it an attractive and powerful tool for studying ecosystem primary productivity, at scales ranging from local to global. This paper aims to use Moderate Resolution Imaging Spectroradiometer (MODIS) data to estimate and analyze spatial and temporal distribution of NPP of the northern Hebei Province in 2001 based on Carnegie-Ames-Stanford Approach (CASA) model. The spatial distribution of Absorbed Photosynthetically Active Radiation (APAR) of vegetation and light use efficiency in three geographical subregions, that is, Bashang Plateau Region, Basin Region in the northwestern Hebei Province and Yanshan Mountainous Region in the Northern Hebei Province were analyzed, and total NPP spatial distribution of the study area in 2001 was discussed. Based on 16-day MODIS Fraction of Photosynthetically Active Radiation absorbed by vegetation (FPAR) product, 16-day composite NPP dynamics were calculated using CASA model; the seasonal dynamics of vegetation NPP in three subreglons were also analyzed. Result reveals that the total NPP of the study area in 2001 was 25.1877 × 10^6gC/(m^2.a), and NPP in 2001 ranged from 2 to 608gC/(m^2-a), with an average of 337.516gC/(m^2.a). NPP of the study area in 2001 accumulated mainly from May to September (DOY 129-272), high NIP values appeared from June to August (DOY 177-204), and the maximum NPP appeared from late July to mid-August (DOY 209-224). 展开更多
关键词 NPP distribution MODIS data CASA model Northvrn hebei Province
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Spatial-temporal evolution of vegetation evapotranspiration in Hebei Province,China 被引量:5
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作者 WANG Qian-feng TANG Jia +6 位作者 ZENG Jing-yu QU Yan-ping ZHANG Qing SHUI Wei WANG Wu-lin YI Lin LENG Song 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第9期2107-2117,共11页
Evapotranspiration (ET) is the sum of soil or water body evaporation and plant transpiration from the earth surface and ocean to the atmosphere, and thus plays a significant role in regulating carbon and water resou... Evapotranspiration (ET) is the sum of soil or water body evaporation and plant transpiration from the earth surface and ocean to the atmosphere, and thus plays a significant role in regulating carbon and water resource cycles. The time-series data set from the remote sensing MOLDS product (MOD16) was used to study the spatial-temporal evolution of vegetation evapotranspiration in salinized areas during 2000-2014 by analyzing the variability, spatial patterns and Mann-Kendall (MK) nonparametric trends for the time series. The results indicate that inter-annual and intra-annual variations of ET across various vegetated areas show seasonal changes, with the abnormal months identified. The Cultivated land displays a greater degree of spatial heterogeneity and the spatial pattern of ET in the area covered by broadleaved deciduous forests corresponds to a higher ET rate and increased water consumption. Awidespread decline of ET is observed only in cultivated areas. However, agricultural cultivation doesn't worsen water shortage and soil salinization problems in the region, and water shortage problems are worsening for other vegetated areas. This research provides a basis of reference for the reasonable allocation of water resources and restructuring of vegetation patterns in salinized areas. 展开更多
关键词 EVAPOTRANSPIRATION hebei Province MODIS spatial pattern VEGETATION spatial-temporal evolution
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Atmospheric Circulation and Dynamic Mechanism for Persistent Haze Events in the Beijing–Tianjin–Hebei Region 被引量:68
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作者 Ping WU Yihui DING Yanju LIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第4期429-440,共12页
In this study, regional persistent haze events(RPHEs) in the Beijing–Tianjin–Hebei(BTH) region were identified based on the Objective Identification Technique for Regional Extreme Events for the period 1980–201... In this study, regional persistent haze events(RPHEs) in the Beijing–Tianjin–Hebei(BTH) region were identified based on the Objective Identification Technique for Regional Extreme Events for the period 1980–2013. The formation mechanisms of the severe RPHEs were investigated with focus on the atmospheric circulation and dynamic mechanisms. Results indicated that:(1) 49 RPHEs occurred during the past 34 years.(2) The severe RPHEs could be categorized into two types according to the large-scale circulation, i.e. the zonal westerly airflow(ZWA) type and the high-pressure ridge(HPR) type. When the ZWA-type RPHEs occurred, the BTH region was controlled by near zonal westerly airflow in the mid–upper troposphere.Southwesterly winds prevailed in the lower troposphere, and near-surface wind speeds were only 1–2 ms^-1. Warm and humid air originating from the northwestern Pacific was transported into the region, where the relative humidity was 70% to 80%, creating favorable moisture conditions. When the HPR-type RPHEs appeared, northwesterly airflow in the mid–upper troposphere controlled the region. Westerly winds prevailed in the lower troposphere and the moisture conditions were relatively weak.(3) Descending motion in the mid-lower troposphere caused by the above two circulation types provided a crucial dynamic mechanism for the formation of the two types of RPHEs. The descending motion contributed to a reduction in the height of the planetary boundary layer(PBL), which generated an inversion in the lower troposphere. This inversion trapped the abundant pollution and moisture in the lower PBL, leading to high concentrations of pollutants. 展开更多
关键词 Beijing–Tianjin–hebei region regional persistent haze events atmospheric circulation dynamic mechanism
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Important Events and Chronological Framework of the Early Precambrian Granulite Terrain,Northwestern Hebei Province 被引量:3
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作者 Geng Yuansheng, Liu Dunyi and Song BiaoInstitute of Geology, Chinese Academy of Geological Sciences, 26 Baiwanzhuang,Beijing 100037, China 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1997年第4期466-479,共14页
Based on the chronological data and relevant geological evidence, the chronological framework of the major geological events of the granulite terrain in northwestern Hebei Province and its adjacent areas has been esta... Based on the chronological data and relevant geological evidence, the chronological framework of the major geological events of the granulite terrain in northwestern Hebei Province and its adjacent areas has been established. Basic lava eruption occurred in the span of 2868-2932 Ma, resulting in the formation of the early crust. The TTG magma emplacement took place c.2761 Ma ago. Subsequently basic magma intruded into the supracrustal rocks at 2650 Ma, resulting in crustal thickening. The thickening was enhanced at 2561-2503 Ma by the widespread intrusions of granodioritic magma. In the period of 2477-2461 Ma charnockite intruded, accompanied by regional granulite facies metamorphism. The second stage of granulite facies metamorphism occurred c. 2300 Ma ago, and finally pink granite intrusions at 2144-2087 Ma resulted in the formation of a granite zone. 展开更多
关键词 geological event Early Precambrian GEOCHRONOLOGY GRANULITE northwestern hebei
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Process and mechanism of arable land change in Hebei Province during the past 50 years 被引量:3
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作者 XU Yue-qing (Institute of Geographical Sciences and Natural Resources Research, CAS, Beijing 100101, China College of Resource and Environment Science, Hebei Normal University, Shijiazhuang 050016, China ) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第4期47-52,共6页
Hebei Province is one of the regions with most densely population, fastest economic growth and most intensive land use in China. The contradiction of land shortage sharpened by high-speed economic development with pop... Hebei Province is one of the regions with most densely population, fastest economic growth and most intensive land use in China. The contradiction of land shortage sharpened by high-speed economic development with population growth has become a serious problem, which has restricted regional sustainable development.This paper revealed the basic process, regional differences of change and the gravity center of arable land area according to the long-series statistical data of arable land during the past 50 years. On the basis of the above mentioned, the major driving forces that influence the changes of the arable land are discussed. The research results indicate that there is a trend of obvious fluctuating decrease in arable land area during the last 50 years. The changes of arable land area undergo the process from increase to sharp decrease to gently decrease. The regional disparity of change in arable land area is very notable and the gravity center of arable land area moves to the northeast 49.22 km. Regarding the decrease in arable land, the direct driving forces include adjustments of agricultural structure and reclamation, and indirect driving forces include advance in technology, economic interest and population growth etc. 展开更多
关键词 decrease in arable land area changing process mechanism hebei Province
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Research on ground fissure origins and mechanisms in Hebei Plain,P.R.China 被引量:5
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作者 QI Jian-feng TIAN Meng-ke +1 位作者 CHI Xiu-cheng WANG Cheng-zhen 《Journal of Groundwater Science and Engineering》 2016年第3期188-196,共9页
Ground fissure hazards frequently emerge in Hebei Plain, which damage roads, dams, buildings and farmland. The paper reviews and analyses current state of knowledge and research into ground fissure and geological envi... Ground fissure hazards frequently emerge in Hebei Plain, which damage roads, dams, buildings and farmland. The paper reviews and analyses current state of knowledge and research into ground fissure and geological environment in Hebei Plain. It is shown that the level of research and investigation is in some aspects insufficient. Knowledge is lacking in the use of corresponding geological concept models for specific ground fissures, three-dimensional numerical simulations of ground fissures caused by pumping through soil with pre-existing fractures, numerical simulations of ground fissures caused by dislocation in intersection faults, and the failure criterion and the constitutive relationship of rock and soil. Furthermore, we put forward geological concept models for ground fissure formation following the dislocation of a buried intersection fault, over-exploitation of groundwater and its compound origin mechanisms in order to provide scientific evidence for the quantitative analysis. 展开更多
关键词 hebei Plain Ground fissures Formation mechanisms Numerical simulation Problem analysis
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Experimental Evidence for Hyperfiltration of Saline Water through Compacted Clay Aquitard in the Hebei Plain 被引量:2
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作者 Ying Wang Zongyu Chen +1 位作者 Baoqian Duan Jingli Shao 《Journal of Earth Science》 SCIE CAS CSCD 2014年第6期1076-1082,共7页
It becomes an increasing concern that groundwater quality in exploited deep confined aquifer may deteriorate due to brackish water leakage from its overlying saline aquifer in Hebei Plain. However, the monitoring data... It becomes an increasing concern that groundwater quality in exploited deep confined aquifer may deteriorate due to brackish water leakage from its overlying saline aquifer in Hebei Plain. However, the monitoring data show that the TDS does not significantly change in the exploited aquifer. Some physics or chemistry processes must have taken place in aquitards during brackish leakage. The semi-permeable membrane function of clay aquitard during the process of hyperfiltration(reverse osmosis) should be one of the most important processes. To confirm and test this hyperfiltration mechanism, a series of experiments were performed in which Na Cl solutions were hydraulically forced through different clay sampled from aquitard. The solution 7 g/L in NaC l was forced through at 20 °C by a fluid pressure of 0.5 kN. The results show that hyperfiltration indeed happens in caly aquitard. Semi-permeability is quantified by the reflection coefficient σ. The mean rejection coefficients(σ) for clay samples #1, #2 and #3 were estimated to be 0.063, 0.164 and 0.040, respectively. This behavior of clay was well explained with the theory of the diffuse double layer. The hyperfiltration effect is to the great extent responsible for the chemical process in the aquitard. 展开更多
关键词 clay membrane reverse osmosis HYPERFILTRATION AQUIFER SALT hebei Plain
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