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重庆市嗜人按蚊的分布调查 被引量:2
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作者 蒋诗国 肖邦忠 +4 位作者 唐成田 王卫国 李心术 肖鹏 晏维 《中国寄生虫学与寄生虫病杂志》 CAS CSCD 北大核心 2000年第6期379-379,共1页
关键词 嗜人按蚊 分布 调查 重庆 分布区特征 分布范围
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Ecogeographical characteristics of forest soil animal in mountainous districts of the eastern China 被引量:1
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作者 袁兴中 刘红 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第1期63-66,共6页
In this paper ecogeographical characteristics of forest soil animal i n mountainous districts of the eastern China was analyzed, and results show that soil fauna was very rich in diversified forest habitat, moreover,... In this paper ecogeographical characteristics of forest soil animal i n mountainous districts of the eastern China was analyzed, and results show that soil fauna was very rich in diversified forest habitat, moreover, as times and spaces varied, their compositions and abundance changed obviously too. Forest so il animal decreased gradually in taxa and individual number from the tropics to cold-temperature zone, and they are higher in zonal forest habitat than in other ones on the same mountain. Forest soil animal also got gradually less with incr easing of depth in soil layer, and distributed principally in surface layer. The activities of human had strong affection on faunal composition and diversity of soil animal. On the tropics and subtropics mountains, forest soil animal are le ss in spring-summer than in autumn-winter, whereas they are more in summer-autum n than in winter-spring from warm-temperate zone to cold-temperate zone. 展开更多
关键词 Forest soil animal Faunal characteristics Ecogeographical distribution Eastern China
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Automatic detection of oceanic mesoscale eddies in the South China Sea 被引量:1
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作者 夏琼 申辉 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第5期1334-1348,共15页
This study focuses on the spatial and temporal distribution characteristics of mesoscale eddies in the South China Sea(SCS). An automatic eddy detection method,based on the geometry of velocity vectors,was adopted to ... This study focuses on the spatial and temporal distribution characteristics of mesoscale eddies in the South China Sea(SCS). An automatic eddy detection method,based on the geometry of velocity vectors,was adopted to obtain an eddy dataset from 21 years of satellite altimeter data. Analysis revealed that the number of anticyclonic eddies was nearly equal to cyclonic eddies; in the SCS,cyclonic eddies are generally stronger than anticyclonic eddies and anticyclonic eddies are larger and longer-lived than cyclonic eddies. Anticyclonic eddies tend to survive longer in the spring and summer,while cyclonic eddies have longer lifetimes in the autumn and winter. The characteristics and seasonal variations of eddies in the SCS are strongly related to variations in general ocean circulation,in the homogeneity of surface wind stress,and in the unevenness of bottom topography in the SCS. The spatial and temporal variation of mesoscale eddies in the SCS could,therefore,be an important index for understanding local hydrodynamics and regional climate change. 展开更多
关键词 South China Sea mesoscale eddies eddy detection ALTIMETER STATISTICS
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Characteristics of the May 12,2008 Wenchuan M_S8.0 Earthquake Sequence and Discussion on Relevant Problems 被引量:1
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作者 Jiang Haikun Li Mingxiao Wu Qiong Song Jin 《Earthquake Research in China》 2009年第1期34-47,共14页
The aftershock activity of the May 12, 2008 Wenchuan Ms8.0 Earthquake Sequence shows an obvious segmented feature. Most of the large aftershocks were distributed in the north and south parts of the aftershock zone. Th... The aftershock activity of the May 12, 2008 Wenchuan Ms8.0 Earthquake Sequence shows an obvious segmented feature. Most of the large aftershocks were distributed in the north and south parts of the aftershock zone. Thrusting was dominant with a small amount of strike-slip component in the south part. The aftershock activity decayed gradually, presenting the sequence features of a mainshock-aftershock pattern. The north part was the ending area of the malnshock fracture where strike-slipping was dominant, showing an obvious swarm feature. Therefore it became the major area for large aftershocks. The modulation of the earth tide on aftershock activity is remarkable; most large aftershocks occur during the period of flood and neap tide. The time period around 16:00 was the dominant occurring time for large aftershocks. The p-value, a parameter of modified Omori formula, increases gradually with time, and reaches about 1 at the end. Based on previous study, the sequence patterns, magnitude of maximum aftershock, as well as the duration of aftershock activity has been discussed. The primary results also show that the magnitude difference between the maiushock and the maximum aftershock is proportional to the rupture size of the maiushock for huge earthquakes of about Ms8.0. This means that when the magnitudes of the earthquakes are nearly the same, large rupture size corresponds to sufficient energy release. 展开更多
关键词 May 12 2008 Wenchuan earthquake with Ms8.0 Segmentation features Sequence type Magnitude of maximum aftershock Duration of aftershock activity Rupture size
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The spatial distribution characteristics of shallow fissures of a landslide in the Wenchuan earthquake area 被引量:1
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作者 XU Xing-qian 《Journal of Mountain Science》 SCIE CSCD 2016年第9期1544-1557,共14页
Shallow fissures, being the main infiltration paths of fluid on the surface of a slope, played an important role in the whole process of a landslide. However, the spatial distribution characteristics of fissures in th... Shallow fissures, being the main infiltration paths of fluid on the surface of a slope, played an important role in the whole process of a landslide. However, the spatial distribution characteristics of fissures in the slope are difficult to be determined. In this study, we attempted to characterize the variation pattern of slope fissures along depth in the Wenchuan earthquake area in Sichuan Province by combining engineering geological investigation, geomorphologic analysis and geophysical investigation. The geophysical methods that were used in this study include Multichannel Analysis of Surface Wave(MASW), Ground Penetrating Radar(GPR) and Electrical Resistivity Tomography(ERT). The results suggested that geophysical parameters(shear wave velocity, electromagnetic signals attenuation and resistivity) could provide valuable information for the spatial network of shallow fissures. Through the verification by engineering geological survey and geophysical sensitivity analysis, this work highlighted that MASW was the most appropriate technique to delineate the propagation of shallow fissures in a gravel soil slope. 展开更多
关键词 Shallow fissures LANDSLIDE Wenchuanearthquake Geophysical prospecting
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Study on Body Form and Garment Size Series of the Middle Age and Aged People
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作者 刘瑜 郁进明 《Journal of Donghua University(English Edition)》 EI CAS 2003年第4期60-63,共4页
This paper was designed to analyze on the data, which was obtained from 'National Physique Fitness Investigation Report (2000)'. In order to get the typical body form and figure type of the middle age and aged... This paper was designed to analyze on the data, which was obtained from 'National Physique Fitness Investigation Report (2000)'. In order to get the typical body form and figure type of the middle age and aged people, it was focused on the body form data of this group (age 40 - 60). After calculation and analyzing, the distinguishing feature of body form and the distribution of figure type were deduced. Finally, the re-classification of body form for Chinese middle age and aged people was suggested. It as also suggested that a new garment size series especially for the middle age and aged should be built to fit for these people. This conclusion would be useful and significant to design and production for clothing company, especially that who take the aged people as their target consumer. 展开更多
关键词 Body form body form classification garment size and series middle age and aged people
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Spatial Distribution Characteristic of the b-value in Dabie-Sulu and Its Adjacent Areas
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作者 Wu Pingping Jia Jianpeng 《Earthquake Research in China》 CSCD 2016年第2期253-263,共11页
The Tanlu (Tancheng-Lujiang) fault is one of the major structures in eastern China, which cuts across different blocks and controls the tectonic activity. Using the seismic data from the China Earthquake Networks Ce... The Tanlu (Tancheng-Lujiang) fault is one of the major structures in eastern China, which cuts across different blocks and controls the tectonic activity. Using the seismic data from the China Earthquake Networks Center, we investigate the spatial variations of the b-value in the Dabie-Sulu (Jiangsu-Shandong) organic belt by calculating the b-value of each grid (1~ xl~) from 1970 to 2010. The study shows that: the b-value is smaller in the Tanlu fault and its adjacent area, which might suggest that the major earthquake recurrence period is relatively long due to the lower frequency of small earthquake activity. In both sides of Tanlu fault, the b-value is higher at the edge of Sulu block and the eastern part of Dabie orogenic belt. The b values are higher in North China central orogenic belt, and small earthquake activity which occurred along the central orogenic belt is frequent. Additionally, combined with geological and geophysical study, we find that the b-value has a certain correspondence relationship with the lithologic distribution, which informs us that seismic activity features are closely related to the inhomogeneous media in the crust. 展开更多
关键词 Tanlu(Tancheng-Lujiang) fault b-value Earthquake activity Earthquakefrequency
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Distribution characteristics of China's key cultural relic tourism resources and suggestions to its development and protection
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作者 YU Zhong-yuan LI Bo BI Hua 《Ecological Economy》 2010年第4期447-456,共10页
SPSS13.0 was used to process the data of the 1-6 batch of key cultural relic conservation units promulgated by the State Administration of Cultural Heritage of China;and multi-element evaluation method was used to cal... SPSS13.0 was used to process the data of the 1-6 batch of key cultural relic conservation units promulgated by the State Administration of Cultural Heritage of China;and multi-element evaluation method was used to calculate the composite distribution index.The spatial distribution of cultural relics of provinces in China can be divided into four grades,namely:very rich areas,rich areas,poor areas and very poor areas;the article analyzes the characteristics of cultural resources in spatial and temporal distribution.The paper holds that(1)the distribution of China's cultural relic tourism resources is relatively concentrated,different sharply from region to region,with more Han nation's heritage,less relics of the ethnic minorities;(2) Henan,Hebei,Shaanxi,Shanxi Province are the main regions with heavy distribution of cultural resources;(3) relics appeared in specific time periods in China's history.Ming and Qing Dynasties,Sui,Tang and Five Dynasties,Song,Liao and Jin,the Western Han,Shang and Zhou dynasties,the New Stone Age are the major periods producing more cultural relics.This paper also analyzes relationships of the emergence of cultural relics with production technology,specific historical process,specific geographical location,political system,religion,national culture,customs,architectural styles and techniques of the traditional cultural educational system.Finally,the paper discusses the development and protection of heritage. 展开更多
关键词 Cultural relic resources Distributional characteristics Development and protection
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北京地区FLEXPART模式适用性初步研究 被引量:14
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作者 李岩 安兴琴 +2 位作者 姚波 周凌晞 左洪超 《环境科学学报》 CAS CSCD 北大核心 2010年第8期1674-1681,共8页
FLEXPART是挪威大气研究所开发的拉格朗日粒子扩散模式.为客观地评价该模式在北京地区的适用性,以北京上甸子大气本底站为例,模拟了CO浓度变化及其源区分布特征,并与该站实测CO浓度和2006年排放源清单进行了比对.结果表明:①模式模拟的C... FLEXPART是挪威大气研究所开发的拉格朗日粒子扩散模式.为客观地评价该模式在北京地区的适用性,以北京上甸子大气本底站为例,模拟了CO浓度变化及其源区分布特征,并与该站实测CO浓度和2006年排放源清单进行了比对.结果表明:①模式模拟的CO浓度变化趋势可以较好地反映上甸子地区CO浓度的日变化规律,CO浓度的模拟值与实测值的相关系数在春夏两季分别达到0.42和0.41;②春夏两季北京市污染气团主要源地分布在西-西南和西西南-南-南南东扇区,模式结果较好地体现了北京及周边地区CO源区的分布特征.初步研究表明,FLEXPART模式在北京地区是基本适用的. 展开更多
关键词 FLEXPART模式 上甸子大气本底站 CO浓度 分布特征
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The vertical distribution characteristics of integral turbulence statistics in the atmospheric boundary layer over an urban area in Beijing 被引量:7
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作者 LIU Yang LIU HuiZhi WANG Lei 《Science China Earth Sciences》 SCIE EI CAS CSCD 2017年第8期1533-1545,共13页
Turbulence data(2008–2012) from a 325 m meteorological tower in Beijing, which consisted of three layers(47,140, and 280 m), was used to analyze the vertical distribution characteristics of turbulent transfer over Be... Turbulence data(2008–2012) from a 325 m meteorological tower in Beijing, which consisted of three layers(47,140, and 280 m), was used to analyze the vertical distribution characteristics of turbulent transfer over Beijing city according to similarity theory. The conclusions were as follows.(1) Normalized standard deviations of wind speeds/ui * were plotted as a function only of a local stability parameter. The values under near-neutral conditions were 2.15, 1.61, and 1.19 at 47 m, 2.39, 1.75,and 1.21 at 140 m, and 2.51, 1.77, and 1.30 at 280 m, showing a clear increase with height. The normalized standard deviation of wind components fitted the 1/3 law under unstable stratification conditions and decreased with height under both stable and unstable conditions.(2) The normalized standard deviation of temperature fitted the.1/3 law in the free convection limit, but was quite scattered with different characteristics under near-neutral conditions. The normalized standard deviations of humidity and the CO2 concentration fitted the.1/3 law under unstable conditions, and remained constant under near-neutral and stable stratification. The normalized standard deviation of scalars, i.e., temperature, humidity, and CO2 concentration, all increased with height.(3) Compared with momentum, and the water vapor and CO2 concentrations, the turbulence correlation coefficient for heat was smaller under near-neutral conditions, but larger under both stable and unstable conditions. A dissimilarity between heat, and the water vapor and CO2 concentrations was observed in urban areas. The relative correlation coefficients between heat and each of momentum, humidity, and CO2 concentration(|rwT/ruw|, |rwT/rwc| and |rwT/ruq|) in the lower layers were always larger than in higher layers, except for the relative correlation coefficient between heat and humidity in an unstable stratification. Therefore, the ratio between heat and each of momentum, humidity, and CO2 concentration decreased with height. 展开更多
关键词 Urban boundary layer Local similarity theory Integral turbulence statistics
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Global vulnerability to agricultural drought and its spatial characteristics 被引量:2
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作者 WU JianJun GENG GuangPo +3 位作者 ZHOU HongKui LIU JingHui WANG QianFeng YANG JianHua 《Science China Earth Sciences》 SCIE EI CAS CSCD 2017年第5期910-920,共11页
As an important part of agricultural drought risk, agricultural drought vulnerability helps effectively prevent and alleviate drought impacts by quantifying the vulnerability as well as identifying its spatial distrib... As an important part of agricultural drought risk, agricultural drought vulnerability helps effectively prevent and alleviate drought impacts by quantifying the vulnerability as well as identifying its spatial distribution characteristics. In this study, global agricultural cultivation regions were chosen as the study area; six main crops(wheat, maize, rice, barley, soybean,sorghum) were selected as the hazard-affected body of agricultural drought. Then, global vulnerability to agricultural drought was assessed at a 0.5° resolution and finally, its distribution characteristics were revealed. The results indicated that the area percentages of different grades of global vulnerability to agricultural drought from low to very high were 38.96%, 28.41%,25.37%, and 7.26%, respectively. This means that the total area percentage of high and very high vulnerability zones exceeded30% of the study area. Although high and very high vulnerability zones were mainly distributed in arid and semi-arid regions,approximately 40% of those above were distributed in humid and semi-humid regions. In addition, only about 15% of the population in this study was located in the high vulnerability regions. Among the vulnerability factors, water deficit during the growing season and the irrigation area ratio are the key factors affecting regional vulnerability. Therefore, the vulnerability could be reduced by adjusting crop planting dates and structures as well as by improving irrigation level and capacity. 展开更多
关键词 Drought Vulnerability Agriculture Spatial distribution Globe
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