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Spatial Morphology Evolution Characteristics Analysis of the Resident Population Distribution in Henan, China
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作者 Kaiguang Zhang Hongling Meng +1 位作者 Mingting Ba Danhuan Wen 《Journal of Geoscience and Environment Protection》 2024年第3期163-180,共18页
The population spatial distribution pattern and its evolving pattern play an important role in regional allocation of social resources and production factors, formulation of regional development plans, construction of... The population spatial distribution pattern and its evolving pattern play an important role in regional allocation of social resources and production factors, formulation of regional development plans, construction of a better life society, and promotion of regional economic development. Based on the resident population statistics data of Henan province from 2006 to 2021, with county as the basic study unit, the paper studies the spatial morphology characteristics and its evolution patterns of resident population distribution, by using spatial analysis methods such as population distribution center, standard deviation ellipse, and spatial auto correlation analysis. The results show that: the resident population spatial distribution shows unbalanced state, the population agglomeration areas mainly distribute in the northeast part and north part, where the resident population growth rate is significantly higher than other regions, over time, this trend is gradually becoming significant. The resident population distribution has a trend of centripetal concentration, with the degree and trend of centripetal gradually strengthening. The resident population distribution has obvious directional characteristics, but the significance is not high, the weighted resident population average center is approximately located at (4.13740˚N, 113.8935˚E), and the azimuth of the distribution axis is approximately 11.19˚. The population distribution has obvious agglomeration characteristics, with the built-up areas of Zhengzhou and Luoyang as their centers, where have a significant siphon effect on the surrounding population. The southern and southwestern regions in the province form a relatively stable belt area of Low-Low agglomeration areas. 展开更多
关键词 Resident Population spatial distribution spatial Morphology Temporal and spatial evolution Center Migration Standard Deviation Ellipse spatial Autocorrelation
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Spatial Distribution and Seasonal Variation of Hypoxic Zone in the Eastern Equatorial Indian Ocean
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作者 XIE Linping WANG Baodong +5 位作者 XIN Ming WANG Ying SUN Xia WEI Qinsheng LIU Lin YUAN Chao 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第4期918-929,共12页
The spatial distribution and seasonal variations of the hypoxic zone in the eastern equatorial Indian Ocean were investigated using survey data collected from four cruises from 2013 to 2018.Results showed that hypoxic... The spatial distribution and seasonal variations of the hypoxic zone in the eastern equatorial Indian Ocean were investigated using survey data collected from four cruises from 2013 to 2018.Results showed that hypoxic zone occurred all year round in the eastern equatorial Indian Ocean,and it spread southward in the shape of a double tongue at two depths with one at subsurface centered at a depth of 150 m and the other in intermediate water centered at a depth of 800 m.The southward expansion and maximum thickness of the hypoxic zone were greatest in the spring inter-monsoon and least in the summer monsoon.The hypoxic zone originated from the southward expansion of the hypoxic water in the Bay of Bengal and its spatial distribution was driven by southward output flux of mid-deep(100–1000 m)hypoxic water from the Bay of Bengal.The hypoxia southward expansion was blocked near the equator in the subsurface layer,because of mixing with multiple zonal circulations(e.g.,Wyrtki Jets and the equatorial undercurrent),which meant that the hypoxic zone extended over a smaller area than in the intermediate water.These new findings will contribute to an improved understanding of the hypoxic zone and will contribute to circulation research,particularly about intermediate circulation in the eastern equatorial Indian Ocean. 展开更多
关键词 hypoxic zone spatial distribution vertical structure seasonal variation eastern equatorial Indian Ocean
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Community structure and spatial distribution of macrobenthos in the shelf area of the Bering Sea 被引量:4
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作者 WANG Jianjun HE Xuebao +6 位作者 LIN Heshan LIN Junhui HUANG Yaqin ZHENG Chengxing ZHENG Fengwu LI Rongguan JIANG Jinxiang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第6期74-81,共8页
Field investigations of marine macrobenthos were conducted at ten sites in the Bering Sea in July 2010. Altogether 90 species of macrobenthos belonging to 59 families and 78 genera were identified. Among them, 41 poly... Field investigations of marine macrobenthos were conducted at ten sites in the Bering Sea in July 2010. Altogether 90 species of macrobenthos belonging to 59 families and 78 genera were identified. Among them, 41 polychaetes, 16 mollusks, 23 crustaceans, three echinoderms, two cnidarians, one nemertean, one priapulid, two sipunculids, and one echiuran were identified. The average density and biomass of total macrobenthos were 984 ind./m2 and 1207.1 g/ma of wet weight, respectively. The predominant species in the study area were Scoloplos armiger, Eudorella pacifica, Ophiura sarsii, Heteromastus filiformis, Ennucula tenuis, and Harpiniopsis vadiculus by abundance, while the predominant species in this area was Echinarachnius parma by biomass. Hierarchical cluster analysis (Bray-Curtis similarity measure) revealed that two impor- tant benthic assemblages in the study area were CommunityA and Community B. CommunityA was stable and Community B was unstable, as shown by the Abundance/Biomass Comparisons (ABC) approach. The macrobenthic community structure in the shelf of the Bering Sea was characterized by its high abundance and biomass, high productivity but great heterogeneity. 展开更多
关键词 Bering Sea marine macrobenthos community structure spatial distribution DIVERSITY
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Temporal-spatial distribution and ore-forming material source of gold,copper and silver polymetallic ore deposits in the Fuping mantle structure zone 被引量:6
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作者 WANG Baode NIU Shuyin +6 位作者 SUN Aiqun LIU Yaming XIE Yan JIANG Xiaoping ZHAO Yongli GAO Yincang ZHAO Fuwang 《Chinese Journal Of Geochemistry》 EI CAS 2010年第3期270-277,共8页
This study was conducted following research on metallogenesis in the Zhangjiajie-Xuanhua and East Hebei mantle branch structure zones. The Fuping mantle branch structure zone is one where Au, Cu and Ag poly-metallic o... This study was conducted following research on metallogenesis in the Zhangjiajie-Xuanhua and East Hebei mantle branch structure zones. The Fuping mantle branch structure zone is one where Au, Cu and Ag poly-metallic ore resources are concentrated in North Hebei. However, there has existed a long-standing controversy on the temporal-spatial distribution of ore resources and their ore-forming material sources. In terms of age dating and the comprehensive analysis of S, Pb, O, C and Si isotopes, it is considered that the temporal-spatial distribution of ore resources in this mantle branch structure zone is obviously controlled by the Fuping mantle branch structure. In space there is developed such a metallogenic pattern as to be Ag, Pb and Zn polymetallic ore deposits with gold appearing inside and copper appearing outside. Metallogenesis is dated mainly at Yanshanian, the ore-forming materials were derived predominantly from the deep interior of the Earth, and ore-forming fluids were derived largely from Yanshanian magmatism. 展开更多
关键词 银多金属矿 成矿作用 多金属矿床 时空分布 物质来源 构造带 黄金
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General Patterns of Spatial Distribution of the Integral Characteristics of Benthic Macrofauna of the Northwestern Pacific and Biological Structure of Ocean
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作者 Igor V. Volvenko 《Open Journal of Ecology》 2014年第4期196-213,共18页
Horizontal (geographic) and vertical (geonemic) spatial distribution of the integral properties of a large multispecies assemblage (1306 species of fish and invertebrate with body size ≥ 1 cm) from northwest Pacific ... Horizontal (geographic) and vertical (geonemic) spatial distribution of the integral properties of a large multispecies assemblage (1306 species of fish and invertebrate with body size ≥ 1 cm) from northwest Pacific sea bottom is investigated. There are total number and biomass, average animal size (mean individual weight), species diversity (Shannon’s index) and its components: species richness and evenness (Pielou’s index), i.e. generalized parameters describing benthic macrofauna as a whole. Correlations of these parameters with distance from shore and depth have been found as well as very weak latitudinal zonality display in the region. Even such well-known generalization as Humboldt-Wallace’s law and Bergman’s rule has no noticeable manifestations here. Earlier similar, but not identical, regularities were discovered in the northwest Pacific pelagic water layer. Collation of what there is in the two different sea zones results in new supplements to Zenkevich-Bogorov’s concept of biological structure of the ocean. 展开更多
关键词 BENTHIC MACRofAUNA spatial distribution INTEGRAL CHARACTERISTICS Biological structure NORTHWESTERN PACIFIC
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The Effect of Spatial Structure Character of Heat Source on the Ray Path and the Evolution of Wave Energy of Meridional Wave Train
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作者 徐祥德 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1991年第1期87-98,共12页
This paper studies correlations between the spatial structure character of thermal forcing and deformation and the amplitude of rays of meridional wave train. It is shown that if thermal forcing appears a meridional l... This paper studies correlations between the spatial structure character of thermal forcing and deformation and the amplitude of rays of meridional wave train. It is shown that if thermal forcing appears a meridional linear variation the rays of quasi-stationary planetary wave may propagate along oblique lines and if the meridional variability of heat source has second order term the rays show distinct deformation as a great circular route. Additionally, the inhomogeneous distribution may cause lower frequency oscillations in mid- and low-latitudes. The combination of zonal and meridional wave numbers and distributive character of heat source may form an inverse mechanism of variational trend of generized wave energy, reflecting in some degree the physical process of transition between meridional and zonal flow patterns. 展开更多
关键词 the Effect of spatial structure Character of Heat Source on the Ray Path and the evolution of Wave Energy of Meridional Wave Train PATH Wave
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SPATIAL STRUCTURE EVOLUTION OF SYSTEM OF RECREATION BUSINESS DISTRICT——A Case of Suzhou City 被引量:13
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作者 LILi-mei TAOWei 《Chinese Geographical Science》 SCIE CSCD 2003年第4期370-377,共8页
The growing attention on urban tourism was very widespread. There are two angles to study urban tourism: supply-side and demand-side. And the supply-side of the tourism remains very important. The RBD (Recreation Busi... The growing attention on urban tourism was very widespread. There are two angles to study urban tourism: supply-side and demand-side. And the supply-side of the tourism remains very important. The RBD (Recreation Business District) is a useful framework to understand the components of urban tourism and how they fit together. The paper begins with a review on the RBD and the spatial structure of tourism in urban areas and then attempts to develop a more general understanding of the spatial structure evolution of RBDs in a tourist-historic city-Suzhou. The spatial structures and functions of the RBDs in Suzhou are examined, based on field observations, interviews with city officials and industry leaders, and a review of available documents. The urban tourism of Suzhou has developed in a range of contexts, that various types of RBDs have emerged as a result of different urban development strategies. The spatial structure has evolved from the past "Single-cored Structure" to "Double-cored Structure" at present, and then to "Chain Structure" in the future. The spatial form and evolution of RBD in Suzhou are closely relative with its urban spatial expansion. Urban area dispersal is the prerequisite of the emergence of the RBD. Planning and constructing the RBD becomes a new impetus to urban growth or renewal. Finally, a number of strategies for planning and developing the RBD in Suzhou are suggested. The different RBDs should adopt different strategies. Intensification can be the possible strategy for the RBDs in the ancient city. Accreting with the urban theme park or engrafting on the Jinji Lake is suggested respectively for the RBD in the Suzhou New District and the Suzhou Industrial Park. 展开更多
关键词 苏州市 商业娱乐区 空间结构发展 苏州新区 苏州老城 苏州工业区
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Analysis of structural characteristics and spatial distribution of the national intangible cultural heritage in China and its policy implications 被引量:1
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作者 BaiCui Xu JingHu Pan 《Research in Cold and Arid Regions》 CSCD 2019年第5期389-406,共18页
Based on an investigation of four published batches listing 3, 140 national intangible cultural heritage(ICH) projects in China and using GIS and some quantitative analysis methods, the spatial structure was investiga... Based on an investigation of four published batches listing 3, 140 national intangible cultural heritage(ICH) projects in China and using GIS and some quantitative analysis methods, the spatial structure was investigated and the characteristics and distribution discussed. The distribution of ICHs in China is agglomerative and spatially dependent. From the view of ICH type, each type is distributed in different places, for different reasons, with history being the most important one we found. Nationwide, high-density cores are located in the Beijing-Tianjin-Hebei region and the Yangtze River Delta region. High densities of ICH are concentrated in flat, water-rich regions where broad-leaved forests dominate plains and low mountain areas-areas that have fertile soil, pleasant weather, a long history of culture, ethnic agglomeration, and development. This paper suggests that development of the ICH should be based on discovering unknown items, to break the existing pattern of strong cohesion and high density, and to seek a balanced development of the whole. 展开更多
关键词 NATIONAL INTANGIBLE culture heritage ICH spatial structure influencing factor GEOGRAPHICAL distribution China
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Temporal and spatial distribution of Au-Ag polymetallic ore deposits and source of ore-forming materials in the Zhangjiakou-Xuanhua mantle-branch metallogenetic zone 被引量:5
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作者 王宝德 吴新国 +2 位作者 牛树银 孙爱群 胡华斌 《Chinese Journal Of Geochemistry》 EI CAS 2007年第2期123-131,共9页
The Zhangjiakou-Xuanhua area is a mineral resource-concentrated area for gold-silver polymetallic ore deposits. The temporal and spatial distribution and origin of mineral resources have been argued for a long time. B... The Zhangjiakou-Xuanhua area is a mineral resource-concentrated area for gold-silver polymetallic ore deposits. The temporal and spatial distribution and origin of mineral resources have been argued for a long time. Based on the comprehensive studies of geochronology and sulfur, lead, oxygen, carbon and noble gas isotopes, it is considered that the temporal and spatial distribution of mineral resources in this area is obviously controlled by the Zhangjiakou-Xuanhua mantle branch structure, as is reflected by the occurrence of gold deposits in the inner parts and of Ag-Pb-Zn polymetallic ore deposits in the outer parts. The mineralization took place mainly during the Yanshanian period. Ore-forming materials came largely from the deep interior of the Earth, and hydrothermal fluids were derived predominantly from Yanshanian magmatism. 展开更多
关键词 张家口-宣化幔枝构造 成矿带 金-银多金属矿床 时空分布 成矿物质 来源
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RESEARCH ON THE SPATIAL STRUCTURE OF KARST MASSIF——Taking the Basin of the Houzhai Subterranean Stream in Puding Country for Example
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作者 张兆干 张建新 +1 位作者 杨剑民 申屏 《Chinese Geographical Science》 SCIE CSCD 1998年第3期65-72,共0页
I.INTRODUCTIONUptothepresent,severaltheoreticalandimportantpracticalproblemshavebeensolvedinkarstgeomorpholo... I.INTRODUCTIONUptothepresent,severaltheoreticalandimportantpracticalproblemshavebeensolvedinkarstgeomorphology.However,alongw... 展开更多
关键词 KARST MASSIF spatial structure geomorphic evolution SUBTERRANEAN STREAM Puding
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Spatial distribution of aloricate ciliates in the stratified water of the Cosmonaut and Cooperation Seas in the Southern Ocean
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作者 LI Jingyuan LI Haibo +2 位作者 WANG Chaofeng ZHANG Wuchang XIAO Tian 《Advances in Polar Science》 CSCD 2022年第4期313-325,共13页
Aloricate ciliates are the main component of microzooplankton.They play important roles in the circulation of materials and flow of energy in marine pelagic ecosystems.To determine the distribution pattern and structu... Aloricate ciliates are the main component of microzooplankton.They play important roles in the circulation of materials and flow of energy in marine pelagic ecosystems.To determine the distribution pattern and structure of the aloricate ciliate community in vertically stratified waters of the Southern Ocean,we collected data on aloricate ciliates in the Cosmonaut and Cooperation Seas during the 36th Chinese National Antarctic Research Expedition.The ranges of aloricate ciliate abundance and biomass were 5-3097 ind·L^(-1)and 0.01-11.40μg C·L^(-1),respectively.Vertically,the average abundance of aloricate ciliates decreased from the surface to 200 m,while biomass was highest in the 50-m layer.The importance of aloricate ciliates<20μm increased along the depth gradient.Their contribution to total abundance increased from 13.04%in the surface layer to 73.71% in the 200-m layer.This is the first study to explore the distribution characteristics of the aloricate ciliate community in a stratified water column of the Southern Ocean.Our results will be helpful for understanding the variation in the pelagic community in waters of the Southern Ocean with intensified stratification. 展开更多
关键词 aloricate ciliates spatial distribution community structure STRATIFICATION Southern Ocean
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The Analysis of Spatial-Temporal Evolution of City Accessibility Based on Highway Network in Henan Province in China
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作者 Mingting Ba Hongling Meng +1 位作者 Kaiguang Zhang Yanmin Sun 《Journal of Transportation Technologies》 2021年第2期296-310,共15页
Accessibility is an important tool</span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;&qu... Accessibility is an important tool</span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">to evaluate the maturity of a regional traffic network structure</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> which </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">describes the traffic convenience in the traffic</span><span style="font-family:Verdana;"> network. </span><span style="font-family:Verdana;">The paper defines a new accessibility index by using the resident pop</span><span style="font-family:Verdana;">ulation weighted average value of the sum of inverse of the traveling time </span><span style="font-family:Verdana;">distance and time threshold coming from ordinary traffic network, and then uses this accessibility index to analyze the spatial-temporal characteristics of Henan highway network, as well as its evolution patterns from 2005 to 2020. The results show that with the expansion and improvement of Henan highway network, city accessibility level has been significantly improved, spatial convergence is obvious, the cities in the north central are always High-High aggregation area, the cities in the south are always Low-Low aggregation area, gradually forming the characteristics of Northwest high and Southeast low, relative balance between East and West. There is some non-conforming phenomenon in highway mileage growth and improvement of the city accessibility levels, but this situation is being weakened, the highway network layout is gradually rationalized, the spatial distribution of city accessibility and that of population are beginning to converge. 展开更多
关键词 Highway Network ACCESSIBILITY Inverse of Time Distance spatial distribution spatial-Temporal evolution spatial Aggregation Henan Province
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Community structure and spatial-temporal variation of netzphytoplankton in the Bering Sea in summer
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作者 WANG Yu XIANG Peng +4 位作者 YE Youyin LIN Gengming YANG Qingliang LIN Heshan LIN Mao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第4期99-107,共9页
Marine biodiversity is changing in response to altered physical environment, subsequent ecological changes as well as anthropogenic disturbances. In this study, phytoplankton samples in situ collected in the Bering Se... Marine biodiversity is changing in response to altered physical environment, subsequent ecological changes as well as anthropogenic disturbances. In this study, phytoplankton samples in situ collected in the Bering Sea in July of 1999 and 2010 were analyzed to obtain phytoplankton community structure and spatial-temporal variation between the beginning and end of this decade, and the correlation of phytoplankton community dynamics and environmental factors was investigated. A total of 5 divisions, 58 genera and 153 species of phytoplankton belonging to 3 ecological groups were identified. The vast majority of phytoplankton consisted of diatoms accounting for 66.7% of the total species and 95.2% of the total abundance. Considering differentiation in spatial extent and phytoplankton sample types, there were subtle changes in species composition, large altering in abundance and significant variation in spatial distribution between two surveys. The abundance peak area was located at the Bering Strait while sub peak was found at the Bering Sea Basin. The boreal-temperate diatom was the dominant flora, which was subsequently replaced by eurythermal and frigid-water diatom. Phytoplankton community in the Bering Sea was not a simplex uniform community but composed of deep-ocean assemblage and neritic assemblage. The deep-ocean assemblage was located in the northwestern Pacific Ocean and Bering Sea Basin, dominated by boreal-temperate species(Neodenticula seminae, Thalassiothrix longissima, Amphiprora hyperborean, Chaetoceros atlanticus, Thalassiosira trifulta, etc.) and eurychoric species(Thalassionema nitzschioides, Ch. compressus, Rhizosolenia styliformis, etc.), and characterized by low abundance, even interspecies abundance allocations, diverse dominant species and high species diversity. The neritic assemblage was distributed on the continental shelf and slope of Bering Sea and was mainly composed of frigid-water species(Th.nordenski?ldii, Ch. furcellatus, Ch. socialis, Bacteriosira fragilis, etc.) and eurythermal and euryhaline species(L.danicus, Ch. curvisetus, Coscinodiscus curvatulus, etc.), and it was characterized by high abundance, uneven interspecies allocations, prominent dominant species and low species diversity. Spatial-temporal variation of species composition and abundance of phytoplankton in the Bering Sea was directly controlled by surface circulation,nutrient supply and ice edge. 展开更多
关键词 Bering Sea phytoplankton community structure spatial and temporal variation distribution environment changes
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Spatial Distribution and Tectonic Evolution of Ultrahigh-P(UHP) and High-P(HP) Metamorphic Belts in Central and Eastern China
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作者 J.G.Liou W.G.Ernst +7 位作者 Xiaomin WANG Ruyuan ZHANG E.Eide Jun LIU S.Maruyama Leslie Ames Gaozhi ZHOU Yuanjun LIU 《资源环境与工程》 2016年第B04期76-88,共13页
关键词 UHP spatial distribution and Tectonic evolution of Ultrahigh-P and High-P HP Metamorphic Belts in Central and Eastern China
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The Evolution Characteristics of Spatial Layout of Ancient Chinese Capitals: A Case Study of Sui,Tang and Northern Song Dynasties With Important Changes in the Historical Development of Feudal Society
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作者 LIN Yuzhen 《Journal of Landscape Research》 2020年第1期45-48,共4页
Imperial city and outer city are the most important differentiation of the spatial structure of ancient Chinese capitals.The relationship between city and Guo changed from the original spatial structure mode of "... Imperial city and outer city are the most important differentiation of the spatial structure of ancient Chinese capitals.The relationship between city and Guo changed from the original spatial structure mode of "respecting the west" and "sitting in the west and facing the east" to the spatial structure mode of "sitting in the north and facing the south" and the three outer cities in the east,south and west surrounding the imperial city after the Wei,Jin,Southern and Northern Dynasties,and gradually changed from the original "multi palace" system to the "single palace" system.Finally,a "heavy city" capital spatial structure with the outer city around the imperial city and the imperial city around the palace city,and the central axis of the chessboard format was formed.During the Tang and Song Dynasties,it was a period of great change in the history of feudal society in China.Through the investigation of the evolution characteristics of the spatial form of capital cities in the Tang and Song Dynasties,the track of the transformation of social ideology,political system,economic structure and many other fields in the Tang and Song Dynasties was made clear. 展开更多
关键词 Ancient capital Tang and Song Dynasties spatial structure evolution
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Population structure and distribution pattern of Taxus cuspidata in Muling region of Heilongjiang Province, China 被引量:9
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作者 ZU Yuan-gang CHEN Hua-feng WANG Wen-jie NIE Shao-quan 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第1期80-82,共3页
An investigation was conducted on distribution pattern, site condition and population structure of yew Taxus cuspidata Sieb. et Zucc. in Muling Forest Bureau of Heilongjiang Province, China in April, 2005. Results sho... An investigation was conducted on distribution pattern, site condition and population structure of yew Taxus cuspidata Sieb. et Zucc. in Muling Forest Bureau of Heilongjiang Province, China in April, 2005. Results showed that yew is mainly distributed under the main storey of natural mixed forest of conifer and broadleaf, the soil moisture content of the yew site is high (40%-60%), the pH value of soil is relatively lower (4.7-5.5), and that the population structure of wild yew is not rational, belonging to the degeneration population, which is one of the reasons leading to the population decline. Although the site conditions of Muling area are suitable for the growth of wild yew, the population of wild yew shows a decline tendency, due to the fact that the middle-sized adult yew trees have been cut, young yews are often grazed by wildlife, and that the trunks of adult yew tend to be hollow. 展开更多
关键词 Taxus cuspidata Sieb. et Zucc. YEW Population structure spatial distribution pattern Site conditions
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Standing stock and community structure of photosynthetic picoplankton in the northern South China Sea 被引量:3
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作者 NINGXiuren LIWKW +2 位作者 CAIYuming LIUChenggang SHIJunxian 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第2期57-76,共20页
The investigation on community structure of standing stock of photosynthetic picoplankton: Synechococcus (Syn), Prochlorococcus (Pro) and Picoeukaryotes (Euk) and their environmental regulation mechanisms in the north... The investigation on community structure of standing stock of photosynthetic picoplankton: Synechococcus (Syn), Prochlorococcus (Pro) and Picoeukaryotes (Euk) and their environmental regulation mechanisms in the northern South China Sea was carried out in the summer of 1999. The results showed that the average abundances of Syn, Pro and Euk in the study sea areas were (5.0±7.6)×104 cell/cm3 (51%), (4.6±4.2)×104 cell /cm3 (47%) and (1.8±1.1)×103 cell/cm3 (2%) respectively, and those of their carbon biomass were (12.5±18.9) ?滋g/dm3 (74%), (2.7±2.5) ?滋g/dm3 (16 %) and (1.7±1.0) ?滋g /dm3 (10%). The most of high values of Syn appeared in the estuaries, coastal zone and continental shelf in the sea area to the east of Leizhou Peninsula and Hainan Island where nutrients were rich, and those appeared in the Beibu Gulf were the second, while those appeared in continental slope and open sea were tens times lower than the above those. Its distribution in water column was mainly above the thermocline and its abundance below it sharply decreased. Two different populations of Pro were found, the surface population and deep one. The distribution pattern of the former was similar to that of Syn; while with marked difference from that of the former, the abundance and biomass of the latter markedly increased towards outer sea, continental slope and open sea where nutrients were poor; the high values in the water column mainly appeared at the bottom of euphotic zone and above the nitrocline, where it often vigorously grow. The distribution difference of Euk in the various sea areas is not as obvious as those of Syn and Pro, but it was high in coastal and shelf waters and low in continental slope and open sea. The high values in the water column were mostly appeared at the bottom of euphotic zone. This difference of distribution pattern for the three type of photosynthetic picoplankton depends on environmental effects and their ecophysiological differences. 展开更多
关键词 SYNECHOCOCCUS PROCHLOROCOCCUS photosynthetic picoeukaryotes cell abundance biomass community structure spatial distribution
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Population structure and spatial pattern analysis of Quercus aquifolioides on Sejila Mountain,Tibet,China 被引量:1
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作者 Zhiqiang Shen Jie Lu +4 位作者 Min Hua Xiaoqin Tang Xingle Qu Jingli Xue Jiangping Fang 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第2期400-409,共10页
Understanding population structure provides basic ecological data related to species and ecosystems.Our objective was to understand the mechanisms involved in the maintenance of Quercus aquifolioides populations.Using... Understanding population structure provides basic ecological data related to species and ecosystems.Our objective was to understand the mechanisms involved in the maintenance of Quercus aquifolioides populations.Using a 1 ha permanent sample plot data for Q.aquifolioides on Sejila Mountain,Tibet Autonomous Region(Tibet),China,we analyzed the population structure of Q.aquifolioides by combining data for diameter class,static life table and survival curve.Simultaneously,the spatial distribution of Q.aquifolioides was studied using Ripley’s L Function in point pattern analysis.The results showed:(1) Individuals in Q.aquifolioides populations were mainly aggregated in the youngest age classes,that accounted for94.3% of the individuals; the older age classes had much smaller populations.Although the youngest age classes(ClassesⅠ and Ⅱ) had fewer individuals than Class Ⅲ,the total number of individuals in classes Ⅰ and Ⅱ was also greater than in classes Ⅳ to Ⅸ.In terms of tree height,fewsaplings,more medium-sized saplings and few large-sized trees were found.The diameter class structure of Q.aquifolioides populations formed an atypical ‘pyramid’type; the population was expanding,but growth was limited,tending toward a stable population.(2) Mortality of Q.aquifolioides increased continuously with age; life expectancy decreased over time,and the survivorship curve was close to a Deevey I curve.(3) The spatial distribution pattern of Q.aquifolioides varied widely across different developmental stages.Saplings and medium-sized tree showed aggregated distributions at the scales of 0–33 m and 0–29 m,respectively.The aggregation intensities of saplings and medium-sized trees at small scales were significantly stronger than that of large-sized trees.However,large-sized trees showed a random distribution at most scales.(4) No correlation was observed among saplings,medium-and large-sized trees at small scales,while a significant and negative association was observed as the scale increased.Strong competition was found among saplings,medium-and large-sized trees,while no significant association was observed between medium-and largesized trees at all scales.Biotic interactions and local ecological characteristics influenced the spatial distribution pattern of Q.aquifolioides populations most strongly. 展开更多
关键词 Point pattern analysis Population structure Quercus aquifolioides Sejila Mountain spatial distribution pattern
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Eco-spatial Structure of Urban Agglomeration 被引量:5
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作者 GUO Rongchao MIAO Changhong +1 位作者 LI Xuexin CHEN Deguang 《Chinese Geographical Science》 SCIE CSCD 2007年第1期28-33,共6页
In terms of ecological theory, this paper makes a comprehensive analysis of the mutualism and co- evolutionary mechanism between the eco-spatial structure and socio-economic development of the urban agglomeration, and... In terms of ecological theory, this paper makes a comprehensive analysis of the mutualism and co- evolutionary mechanism between the eco-spatial structure and socio-economic development of the urban agglomeration, and maps out optimized modes of the eco-spatial structure of the urban agglomeration. The analysis is a case study of the urban agglomeration on different levels of global, national, provincial and local scales, on the basis of those conclusions are drawn: 1) Within the scope of the urban agglomeration, the cities should be reasonably sized and appropriately densified; the spatial combination of the urban agglomeration ought to be orderly, and its eco-spatial structure ought to be optimized and efficient; the relationship between the economic society and eco-spatial environment ought to be that of mutual benefit and co-evolution. 2) “The mode of corridor group network” is a certain trend evoked from the spatial structure of urban agglomeration. 3) The eco-spatial structure of urban agglomeration under “the mode of corridor group network” can further increase the environmental capacity of urban agglomeration, and is in favor of the harmonious relationship between man and nature. 展开更多
关键词 城市群 经济-空间结构 互动理论 协同进化理论 经济走廊组网
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Model of Shipping Noise in the Deep Water: Directional Density and Spatial Coherence Functions
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作者 肖鹏 杨坤德 雷波 《China Ocean Engineering》 SCIE EI CSCD 2016年第4期591-601,共11页
The shipping noise properties in the deep ocean are studied. Shipping noise exhibits the strong dual-horned directionality features in the flat-seabed ocean, and its directional density can be modeled by a Von Mises d... The shipping noise properties in the deep ocean are studied. Shipping noise exhibits the strong dual-horned directionality features in the flat-seabed ocean, and its directional density can be modeled by a Von Mises distribution. With the explicit expression for the directional density function, the spatial coherence functions of shipping noise are also derived, and the relative features are studied. The research result shows that the properties of shipping noise are different from the ambient noise of other sources, and it can be used for the sonar array design. The model is well matched with the experimental result, and it can be extended to the situations when the ambient noise exhibits the dual-horned structure. 展开更多
关键词 shipping noise dual-horued structure Von Mises distribution directional density spatial coherence
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