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Relation between Economic Development Level and Resource and Environment Carrying Capacity of Central Area of Yunnan Province Based on Decoupling Analysis 被引量:4
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作者 程超 童绍玉 +2 位作者 彭海英 闫少凯 刘玲 《Agricultural Science & Technology》 CAS 2015年第12期2829-2832,共4页
Based on the decoupiing theory and method, an indicator system was built for the relation between economic development level and resource and environment carrying capacity. And the study was carried out on decoupling ... Based on the decoupiing theory and method, an indicator system was built for the relation between economic development level and resource and environment carrying capacity. And the study was carried out on decoupling degree and temporal changes of economic development level and resource and environment carrying ca- pacity in the central area of Yunnan Province. Results indicated that (i) the economic development level and resource and environment carrying capacity in the central area of Yunnan Province mainly experienced strong decoupling, weak decoupling, and ex- pansive negative coupling, and in general it was strong decoupling, and it took on re- verse "N" in temporal changes. (ii) Change rate of economic development level in the central area of Yunnan Province was greater than zero, but the amplitude of change was not large, while the change rate of resource and environment carrying capacity was negative in 2007-2008, and it was positive in the rest years; from 2007, it took on gradual expansion trend, and scissors difference gradually increased after experi- encing reverse "V" change. (iii) The strong decoupling was the main situation and it reached the peak value in T5 period and T6 pedod. 展开更多
关键词 The central area of Yunnan Province Economic development level Re- source and environment carrying capacity Decoupling analysis Scissors difference
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Geochemical characteristics of soil selenium and evaluation of Serich land resources in the central area of Guiyang City,China 被引量:9
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作者 Ziping Pan Shaolin He +3 位作者 Chaojin Li Wei Men Chengzhi Yan Fang Wang 《Acta Geochimica》 EI CAS CSCD 2017年第2期240-249,共10页
Based on the results of multipurpose regional geochemical surveys of the Guizhou Province, geochemical characteristics of soil Se and Se-rich land resources in the central area of Guiyang City were studied and evaluat... Based on the results of multipurpose regional geochemical surveys of the Guizhou Province, geochemical characteristics of soil Se and Se-rich land resources in the central area of Guiyang City were studied and evaluated.Major conclusions are as follows:(1) the Se content in surface soil of the central area of Guiyang City was 0.17–2.89 mg kg^(-1), and the average was 0.78 mg kg^(-1), which were respectively 2.6 and 3.9 times of the national background value of soil and the world background value of soil.The Se content in deep soil was 0.11–1.48 mg kg^(-1), and the average was 0.44 mg kg^(-1), which were respectively 1.5 and2.2 times of the national background value of soil and the world background value of soil. The soil Se content decreased with the increase in the soil depth on the vertical profile, and the surface soil had a higher Se content.(2)Distribution of Se content was mainly affected by parent material, physicochemical properties of soil and other components, soil type, and land use type. Parent material played a key role, as the soil Se content was mainly originated from parent rock and increased with the background value of Se in parent rock, physicochemical properties of soil and other components had certain influences upon the Se content. Se was shown to have a significant linear positive correlation with S and organic carbon but no significant correlation with p H value. Se content varied with different types of soil as follows: skeleton soil > yellow soil > paddy soil > limestone soil > purple soil. Land use type also hadcertain influences upon the soil Se content as follows: dry land > construction land > garden plot > grassland =garden plot > forest land.(3) Taking 0.4 mg kg^(-1)B x(Se) <3.0 mg kg^(-1) as the standard for Se-rich soil, Se-rich soil of the study area covered an area of 2224 km^2 and 92.5% of the total area; the remaining is general soil. The study area had no Se-excess soil. Therefore, the central area of Guiyang City has a high proportion of Se-rich land, a large area of Serich land resources, and a moderate selenium enrichment strength, which have been rarely seen anywhere and provide advantageous resources for the development of Se-rich featured agriculture. 展开更多
关键词 central area of Guiyang SOILS SELENIUM Geochemical characteristics Evaluation of Se-rich landresource
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Hydrographic structure and circulation in the central area of the North Eastern Atlantic
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作者 Xu Jianping Second Institute of Oceanography, State Oceanic Administration, P. O. Box 1207, Hangzhou 310012, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第3期343-356,共14页
-On the basis of the hydrographic data observed within the Canary Basin in autumn 1985, temperature-salinity properties, distributions of water masses and barocltne flow field, as well as the volume transports in this... -On the basis of the hydrographic data observed within the Canary Basin in autumn 1985, temperature-salinity properties, distributions of water masses and barocltne flow field, as well as the volume transports in this area are described more detailly. The analyses indicate that the activity in the waters of the Canary Basin is mainly attributed to the interleaving and mixing between the originated water masses (e. g. Surface Water, North Atlantic Central Water, Mediterranean Water and Deep Water) and the modified water masses (Subpolar Mode Water, Labrador Sea Water and Antarctic Intermediate Water) from the outside of the study area and the variation of themselves. The east recirculation of the Subtropic Gyre in the North Atlantic consists of Azores Current and Canary Current.Azores Current is formed with several flow branches around the Azores Island, while the main flow lies at 35?N south of the Azores Island. It begins to diverge near the 15?W. The return flow found off the Portugal coast may be its northern branch. The southern invasion of the Labrador Sea Water and the Subpolar Mode Water are prevented by Azores front which serves an obvious boundary separating the North Western Atlantic (Central) Water and the North Eastern Atlantic (Central) Water. 展开更多
关键词 Hydrographic structure and circulation in the central area of the North Eastern Atlantic area
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Burial fluxes and sources of organic carbon in sediments of the central Yellow Sea mud area over the past 200 years 被引量:4
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作者 YANG Shu YANG Qian +3 位作者 LIU Sai CAI Deling QU Keming SUN Yao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第10期13-22,共10页
Long-term changes of composition, sources and burial fluxes of TOC (total organic carbon) in sediments of the central Yellow Sea mud area and their possible affecting factors are discussed in this paper. Firstly, si... Long-term changes of composition, sources and burial fluxes of TOC (total organic carbon) in sediments of the central Yellow Sea mud area and their possible affecting factors are discussed in this paper. Firstly, similarity analysis is employed to confirm that the carbon burial features resulted from two collected cores are typical in the central Yellow Sea mud area where YSWC (Yellow Sea Warm Current) is prevalent. On this basis, the burial flux of TOC here was considered to be 235.5-488.4 pmol/(cm^2.a) since the first industrial revolution, accounting for about 70%-90% among burial fluxes of TC (total carbon) in the sediments. Compared TOC/TC ratio in the two cores with that in other marine sediments worldwide, we suggest that the growth of calcareous/non-calcareous organisms and dissolution of IC (inorganic carbon) are important factors controlling the TOC/TC ratio in sediment. Results of two-end mixed model based on fi13C data indicate that marine-derived organic carbon (OCa) is the main part among total burial organic carbon which accounts for a ratio over 85%. Due to the high TOC/TC ratio in the two cores, TC in the sediments also mainly exists as OCa, and the proportion of OCa is about 60%-80%. Away from the shore and relatively high primary production in upper waters are the main reasons that OCa is predominant among all burial OC in sediments of the central Yellow Sea mud area. Burial of OC in this mud area is probably mainly influenced by the human activities. Although the economic development during the late 19th century caused by the first industrial revolution in China did not obviously increase the TOC burial fluxes in the sediments, the rise of industry and agriculture after the founding of new China has clearly increased the TOC burial flux since 1950s. Otherwise, we also realize that among TC burial fluxes, TIC account for about 10%-30% in sediments of the central Yellow Sea mud area, so its burial could not be simply ignored here. Distinct from TOC burial, long-term TIC burial fluxes variations relate with climate changes more closely: the East Asian summer monsoon may influence the strength of the Huanghe River (Yellow River) flood, which could further affect the transport of terrestrial IC from land to the central Yellow Sea as well as the burial of these IC in the sediments. 展开更多
关键词 the central Yellow Sea mud area organic carbon burial flux source long-term changes human activities
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Effects of Land Use Change on Eco-environment in Hilly Area of Central Sichuan Basin——A Case Study of Yanting County, Sichuan Province 被引量:2
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作者 Luo Huai-liang, Zhu Bo, Chen Guo-jie, Gao Mei-rongInstitute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, China College of Resources and Environment, Sichuan Normal University, Chengdu 610066, Sichuan, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03B期981-986,共6页
With the artificial alder and cypress mixed forest being planted, there has been a marked land use change since 1970s' in Hilly Area of Central Sichuan Basin, China. Data from meteorological observations or posts ... With the artificial alder and cypress mixed forest being planted, there has been a marked land use change since 1970s' in Hilly Area of Central Sichuan Basin, China. Data from meteorological observations or posts operated over long time, measurement and calculation of NPP (net primary production) and biomass of biological community, and analysis of soil organic matter content show that the artificial alder and cypress mixed forest has outstanding eco-environmental effect: adjusting local climate, raising soil fertility, alleviating menace of drought, and raising NPP and biomass of biological community. It is very beneficial for improving ecological environment to afforest artificial alder and cypress mixed forest in populous Hilly Area of Central Sichuan Basin, China. Key Words: land use/land cover change (LUCC); eco-environmental effect; Hilly Area of Central Sichuan Basin; the artificial alder and cypress mixed forest 展开更多
关键词 of as for Sichuan Province Effects of Land Use Change on Eco-environment in Hilly area of central Sichuan Basin A Case Study of Yanting County on ECO
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The difference analysis of physical-mechanical properties of sediments in the central South Yellow Sea and Zhe-Min coastal area in China 被引量:1
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作者 XU Yuanqin LI Ping +4 位作者 LI Peiying DU Jun LIU Lejun GAO Wei LIU Jie 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第7期77-85,共9页
The difference analysis of physical-mechanical properties of muddy sediments is made in the central South Yellow Sea and the Zhe-Min(Zhejiang Province to Fujian Province of China) coastal area. The results show that... The difference analysis of physical-mechanical properties of muddy sediments is made in the central South Yellow Sea and the Zhe-Min(Zhejiang Province to Fujian Province of China) coastal area. The results show that sediments in the two regions are both dominated by mud. There are perfect negative power function correlations between the water content and the density, the compression coefficient and the compression modulus; a good positive power function correlation between the liquid limit and the plastic limit, a perfect positive linear correlation between the water content and the void ratio, and a perfect polynomial function correlation between the miniature vane shear strength and the pocket penetration resistance. In general, compared with sediments in the Zhe-Min coastal area, sediments in the central South Yellow Sea possess high water content, high void ratio,low density, high plasticity, high compressibility, low shear strength. The causes of the differences between physical-mechanical properties of sediments are analyzed from the topographic features, material sources,hydrodynamic conditions, deposition rate, and material composition. Compared with the Zhe-Min coastal area,the central South Yellow Sea is far from the Mainland and low-lying; has poor hydrodynamic condition; the materials diffused to the area are less and dominated by fine clay, have the high content of smectite and organic matters. These factors lead to sediments of the central South Yellow Sea has the higher water content, the higher plasticity, the lower density, and the lower strength than sediments in the Zhe-Min coastal area. 展开更多
关键词 sediment Zhe-Min coastal area central South Yellow Sea physical-mechanical properties difference analysis
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Continental reconstruction and metallogeny of the Circum-Junggar areas and termination of the southern Central Asian Orogenic Belt 被引量:22
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作者 Wenjiao Xiao Min Sun M.Santosh 《Geoscience Frontiers》 SCIE CAS CSCD 2015年第2期137-140,共4页
Continental reconstructions in Central Asia are represented by orogenesis along some large orogenic belts in the Altaid collage (Fig. 1 ) or Central Asian Orogenic Belt (CAOB), which separate the East European and... Continental reconstructions in Central Asia are represented by orogenesis along some large orogenic belts in the Altaid collage (Fig. 1 ) or Central Asian Orogenic Belt (CAOB), which separate the East European and Siberian cratons to the north from the Tarim and North China cratons to the south ($eng0r et al,, 1993; Jahn et al., 2004; Windley et al., 2007; Qu et al., 2008; Xiao et al., 2010; Xiao and Santosh, 2014). The Altaid Collage was characterized by complex long tectonic and structural evolution from at least ca. 1.0 Ga to late Paleozoic-early Mesozoic with considerable continental growth (Khain et al., 2002; Jahn et al., 2004; Xiao et al., 2009, 2014; KrOner et al., 2014), followed by Cenozoic intracontinental evolution related to far-field effect of the collision of the In- dian Plate to the Eurasian Accompanying with these complex world-class ore deposits developed 2001; Goldfarb et al., 2003, 2014). Plate (Cunningham, 2005). geodynamic evolutions, many (Qin, 2000; Yakubchuk et al,2001; Goldfarb et al., 2003, 2014). 展开更多
关键词 Continental reconstruction and metallogeny of the Circum-Junggar areas and termination of the southern central Asian Orogenic Belt
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Bidding Scheme Design of Central Recreational Area for Xiaogan Linkong Economic Zone
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作者 WANG Ai'guo SUN Ti 《Journal of Landscape Research》 2016年第5期48-52,共5页
This paper elaborated the bidding scheme design of the Central Recreational Area in Linkong Economic Zone from the perspectives of site analysis, determination of properties, design theme and principle, scheme layout ... This paper elaborated the bidding scheme design of the Central Recreational Area in Linkong Economic Zone from the perspectives of site analysis, determination of properties, design theme and principle, scheme layout and conception, in order to explore the potential enlightenments of the scheme design process, and disclose significance of site analysis and its close relationship with the scheme design. 展开更多
关键词 Linkong Economic Zone central Recreational area Bidding scheme Water show Phoenix dancing
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Spatial and Temporal Distributions of Soil Organic Matter in the Mixed Plantations of Alder and Cypress in the Hilly Areas of Central Sichuan Basin
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作者 WU Pengfei ZHU BO +1 位作者 YANG Yuanli WANG Xiaoguo 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期1021-1027,共7页
The investigation was conducted on the spatial and temporal distributions of soil organic mater (SOM) in the mixed plantations of alder (Aluns crernastogyne) and cypress (Cupressus funebris ) (MPAC), which dis... The investigation was conducted on the spatial and temporal distributions of soil organic mater (SOM) in the mixed plantations of alder (Aluns crernastogyne) and cypress (Cupressus funebris ) (MPAC), which distributed in the hilly areas of central Sichuan Basin (HACSB). The results show that: (1) the spatial distribution of SOM among different sites at the same age are not significant before 15-year-old, but significant at 20-year-old, and not significant again after 25-year-old; (2) the SOM contents in 0-15 cm and 15-30 cm layers increase sharply from 10- to 15-year-old, and decline gradually from 15- to 30- year-old; the SOM contents of the 30-year-old PCP were 80. 38% and 78.42% higher than that of the 10-year-old, but 29.16% and 53.37% lower than that of 15-year-old in the 0-15 cm and 15-30 cm layers, respectively. The decrease of SOM contents would lead to the degradation of soil fertility and the decline of forest productivity. 展开更多
关键词 hilly areas of central Sichuan mixed plantations of alder and cypress soil organic matter spatial distributions temporal dynamics
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Sensitivity Assessment and Optimization Strategy of Climatic Environment in Central Urban Area of Beijing
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作者 YANG Xin GAO Wenwen LI Nana 《Journal of Landscape Research》 2021年第6期1-4,共4页
As one of the methods of urban environmental assessment,sensitivity assessment of urban climatic environment can accurately reflect the problem areas of current urban climate and built environment through visual means... As one of the methods of urban environmental assessment,sensitivity assessment of urban climatic environment can accurately reflect the problem areas of current urban climate and built environment through visual means,and help cities to carry out sustainable transformation and renewal in the stock era to optimize the living environment.Taking the central urban area of Beijing as the research object,the sensitivity of climatic environment was evaluated by meteorological data and built environment element data.The results showed that the distribution of sensitive units showed a centrifugal radiation pattern of"high in the center and low in the periphery".Block units with high climate sensitivity were mostly concentrated in Xicheng District and Dongcheng District,accounting for 93%of the total number of units.Further research showed that complex built environment and lack of elements to regulate climatic environment were the main reasons for the poor local climatic environment in the region with high climate sensitivity.Finally,a comprehensive evaluation of the remolding capacity,renewal potential and future development intensity of different grades of climate sensitive units was given.The results will provide scientific reference for urban renewal and reconstruction under climatic and environmental changes,so as to promote urban sustainable development and improvement of living environment. 展开更多
关键词 central urban area of Beijing Climatic environment Sensitivity Optimization guideline
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Ecological Function Value of Tropical Forests in the Central Mountainous Areas of Hainan Island
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作者 Jing GAO Zuguang ZHOU 《Asian Agricultural Research》 2013年第11期103-105,108,共4页
The integrated value of the ecological function of tropical forests in the central mountainous areas of Hainan Island was 33.064 8 billion yuan/a in 2010(soil improvement,soil consolidation,soil nutrient maintenance,w... The integrated value of the ecological function of tropical forests in the central mountainous areas of Hainan Island was 33.064 8 billion yuan/a in 2010(soil improvement,soil consolidation,soil nutrient maintenance,water storage and moisture regulation,water purification,carbon sequestration,oxygen releasing,air purification,biodiversity conservation,eco-tourism),equivalent to 16.1%of GDP in Hainan Province this year(205.212 billion yuan).The tropical forests in the central mountainous areas of Hainan Island make great contribution to Hainan Island's ecology,and play an important role in maintaining the stability of the ecological environment in Hainan Island.Through the understanding of major ecological function value of tropical forests,it is necessary to make people cherish the tropical forests in the central ecological function conservation areas of Hainan Province,and spontaneously throw themselves into the ecological environment protection and construction,to promote the rapid and sustainable development of construction in Hainan Province as an international tourism island. 展开更多
关键词 central mountainous areas TROPICAL FORESTS Ecologi
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Thinking on Establishing Free Trade Area of Central Asia
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作者 Lunzhi He Ping Cai 《Chinese Business Review》 2003年第4期27-32,共6页
With the economic integration all over the world, it is necessary to establish the free trade area of central Asia, including Xinjiang. This paper analyses the demands on establishing free trade area in central Asia. ... With the economic integration all over the world, it is necessary to establish the free trade area of central Asia, including Xinjiang. This paper analyses the demands on establishing free trade area in central Asia. According to the present statues of Xinjiang and five countries of central Asia, the developmental patterns are suggested. Furthermore, some policies and suggestions are proposed about the existing problems. 展开更多
关键词 western development free trade area of central Asia developmental pattern suggestions
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Petrogenesis and Tectonics of the Naruo Porphyry Cu(Au) Deposit Related Intrusion in the Duolong Area,Central Tibet 被引量:11
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作者 DING Shuai CHEN Yuchuan +3 位作者 TANG Juxing ZHENG Wenbao LIN Bin YANG Chao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第2期581-601,共21页
The Duolong area is the most important part of the Western Bangong-Nujiang Suture Zone porphyry Cu(Au) metallogenic belt, in Tibet, China. Here new detailed data are presented from LAICP-MS zircon U-Pb, whole-rock g... The Duolong area is the most important part of the Western Bangong-Nujiang Suture Zone porphyry Cu(Au) metallogenic belt, in Tibet, China. Here new detailed data are presented from LAICP-MS zircon U-Pb, whole-rock geochemical, and in-situ zircon Hf isotope analyses for igneous rocks in the large Naruo deposit(2.51 Mt of Cu and 82 t of Au) which is located ~2 km NE of the Duolong(Duobuza and Bolong) super-large gold-rich porphyry copper deposit. We integrated our results with previous research of other porphyry deposits in the Duolong area and have identified the timing, geodynamic setting, and petrogenesis of the mineralization-associated magmatic events. Based on the measurements, the Duolong area porphyry Cu(Au) deposit formations are associated with Early Cretaceous intermediate-felsic magmatism, which is consistent with U-Pb zircon ages of 120 Ma. All the main intrusive rocks in the ore-concentrated area have similar lithogeochemical characteristics; they show a relative enrichment in both light rare earth elements(LREEs) and large-ion lithophile elements(LILEs: Rb, Ba, K, etc.) and relative depletion in both heavy rare earth elements(HREEs) and high field strength elements(HFSEs: Nb, Ta, Zr, Hf, etc.). Moreover, the granite porphyry shows positive εHf(t) values between 1.38–7.37 suggesting that magmas were potentially derived from the partial melting of a depleted mantle wedge that had been metasomatized by subducted slab-derived fluids or melts. This paper points out that the formation of the porphyry-epithermal Cu(Au) deposit in the Duolong area was dominated by northward subduction of the Bangongco Tethys Plate beneath the Qiangtang block in the Early Cretaceous(124–114 Ma), when the subducted oceanic crust reached 50–70 km underground and generated different degrees of phase transformation, which lead to a melt produced by dehydration of amphibole minerals, a metasomatized mantle wedge, and induced mantle partial melting that produced the magma. Those deposits occurred in a continental arc tectonic setting, which is similar to the continental margin arc environment of the ocean-continent subduction setting of the Andes metallogenic belt in South America. 展开更多
关键词 geochemical signatures zircon U-Pb Hf isotope Duolong area continental arc depleted mantle central Tibet Proto-Tethys
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完善强农惠农富农支持制度的历史逻辑、理论逻辑和现实逻辑
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作者 钟钰 《新疆师范大学学报(哲学社会科学版)》 北大核心 2025年第3期28-38,共11页
党的二十届三中全会提出“完善强农惠农富农支持制度”,首次把强农惠农富农上升到制度层面,充分彰显了党中央对“三农”工作的高度重视,为加快农业农村现代化提供了强有力的制度保障。深刻领悟完善强农惠农富农支持制度的逻辑内涵,对推... 党的二十届三中全会提出“完善强农惠农富农支持制度”,首次把强农惠农富农上升到制度层面,充分彰显了党中央对“三农”工作的高度重视,为加快农业农村现代化提供了强有力的制度保障。深刻领悟完善强农惠农富农支持制度的逻辑内涵,对推进农业农村现代化、加快建设农业强国具有重要的现实指导意义。文本按照科学研究方法论的论证要求,从历史逻辑、理论逻辑和现实逻辑系统阐释强农惠农富农支持制度。历史逻辑侧重诠释强农惠农富农的对象与支持内容,理论逻辑侧重准确解构强农惠农富农的内涵认知,现实逻辑关注强农惠农富农对于当前“三农”工作的必要性和针对性。 展开更多
关键词 党的二十届三中全会 “三农” 强农惠农富农 支持制度
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耦合“现状—趋势”的城市地表热环境评估
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作者 艾合麦提·那麦提 曾坚 +1 位作者 宋苑震 刘祥 《灾害学》 北大核心 2025年第1期80-85,共6页
针对城市地表热环境评估较少考虑动态变化趋势的问题,该文提出了一种新的耦合“现状—趋势”的城市地表热环境评估方法。采用非参数趋势检验法分析多年地表温度的演变趋势,有效识别地表温度的升高、未变化和降低趋势,并通过与现状地表... 针对城市地表热环境评估较少考虑动态变化趋势的问题,该文提出了一种新的耦合“现状—趋势”的城市地表热环境评估方法。采用非参数趋势检验法分析多年地表温度的演变趋势,有效识别地表温度的升高、未变化和降低趋势,并通过与现状地表温度的耦合叠加,深入挖掘现状地表温度高且呈升高趋势等热环境问题严重且紧迫的关键区域,从而实现对城市热环境状况的全面评估。以天津市中心城区为例的实证研究结果表明,该文所提出的评估方法能够有效地识别具有热环境持续恶化潜能的区域,同时也能揭示长期存在高温状况的重点区域。研究结果为城市规划与热环境精准管理提供科学评估工具,助力制定改善策略,提升热环境质量。 展开更多
关键词 地表热环境评估 地表温度 演变趋势 耦合评估 天津市中心城区
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浅谈GIS技术在避难场所选址中的应用
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作者 杨舒 杨振华 +1 位作者 田茗瑜 王琨 《科学技术创新》 2025年第1期84-87,共4页
随着GIS技术的不断发展,GIS技术在选址领域的优势日益显著,目前已成为该领域研究使用的重要技术手段。本文以包头市中心城区现有的中小学操场作为紧急避难场所的备选点,应用LA模型理论,运用GIS空间分析和网络分析方法,构建紧急避难场所... 随着GIS技术的不断发展,GIS技术在选址领域的优势日益显著,目前已成为该领域研究使用的重要技术手段。本文以包头市中心城区现有的中小学操场作为紧急避难场所的备选点,应用LA模型理论,运用GIS空间分析和网络分析方法,构建紧急避难场所配置模型,讨论其作为紧急避难场所的选址情况,并进行数量优化。最终从102个备选点中确定55个点作为紧急避难场所选址点。本研究可为城市防震减灾规划的紧急避难场所区位优化提供理论基础。 展开更多
关键词 GIS空间分析 公共设施区位配置模型(LA模型) 包头市中心城区 紧急避难场
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城市文化遗产片区保护与活化的全要素治理路径研究——以广州市传统中轴线地区连片保护规划为例
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作者 朱晖 李哲林 +1 位作者 李璐颖 刘垚 《中国名城》 2025年第2期34-41,共8页
立足新时期历史文化保护规划全域全要素统筹要求,在规划范式转型背景下,梳理总结传统历史文化街区保护规划编制内容在体系整合、资源统筹、规划实施层面存在的局限性,从全要素治理角度提出兼具技术方法、社会治理、社会服务维度的历史... 立足新时期历史文化保护规划全域全要素统筹要求,在规划范式转型背景下,梳理总结传统历史文化街区保护规划编制内容在体系整合、资源统筹、规划实施层面存在的局限性,从全要素治理角度提出兼具技术方法、社会治理、社会服务维度的历史片区保护规划编制框架。以广州市传统中轴线地区连片保护规划为例,探索要素与格局新统筹、保护与活化政策新补充、工作机制与数字技术新尝试,建立关联统筹有形与无形遗产、自然与人文景观、管控与协调的全域全要素保护规划体系,通过制定面向活化利用难点的精细化管理实施细则实现社会治理功能,基于政策创新与数字化管理支持实现从规划目标到设计落地实施的全过程公共服务,以期为城市遗产区域的历史文化特色风貌保护、管控与高质量发展提供有效路径。 展开更多
关键词 文化遗产片区 遗产保护与活化 全域全要素 广州市传统中轴线地区
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湘中紫云山花岗岩和暗色包体的源区及其地质意义:来自全岩地球化学及Sr-Nd同位素的证据
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作者 鲁玉龙 肖荣 +5 位作者 彭建堂 黄建中 李欢 王鹏 冷家豪 刘洋 《岩石学报》 SCIE EI CAS 北大核心 2025年第1期135-150,共16页
湘中紫云山花岗质岩体形成于晚三叠世,近年来因其周边众多金属矿床的发现而备受关注。岩体内含有丰富的暗色包体(MMEs),为研究其源区和形成过程提供了一个重要的窗口。本文对紫云山暗色包体进行了全岩主、微量元素分析,并对紫云山花岗... 湘中紫云山花岗质岩体形成于晚三叠世,近年来因其周边众多金属矿床的发现而备受关注。岩体内含有丰富的暗色包体(MMEs),为研究其源区和形成过程提供了一个重要的窗口。本文对紫云山暗色包体进行了全岩主、微量元素分析,并对紫云山花岗岩和暗色包体进行了Sr-Nd同位素分析。暗色包体主要为闪长质-花岗闪长质,SiO_(2)含量在55.24%~68.72%(平均为63.758%),K_(2)O含量为1.22%~6.33%(平均值为2.76%),属于钙碱性系列至高钾钙碱性系列岩石。暗色包体的(^(87)Sr/^(86)Sr)i值为0.714943~0.720623,ε_(Nd)(t)值为-9.53~-6.5,t DM2为1.53~1.78 Ga;主体花岗岩的(^(87)Sr/^(86)Sr)_(i)值为0.718160~0.724384,ε_(Nd)(t)值为-7.4~-8.2,二阶段模式年龄t DM2为1.60~1.67Ga;补体花岗岩的(^(87)Sr/^(86)Sr)_(i)值为0.735888~0.745734,ε_(Nd)(t)值为-10.1~-10.9,二阶段模式年龄t_(DM2)值为1.82~1.89Ga。研究表明:紫云山花岗岩主要来源于变杂砂岩熔融的壳源岩浆,并混合了部分富集幔源岩浆;其中主体花岗岩相较补体花岗岩含有较多的幔源组分,而紫云山暗色包体主要来源于富集地幔。紫云山花岗岩和暗色包体可能是印支期华南板块受周缘板块碰撞挤压后岩石圈伸展减薄,底侵的高温幔源岩浆注入到壳源长英质岩浆房后,两者混合不均的产物。在湘中地区,印支晚期花岗岩与其附近的金(锑)、钨等矿床存在密切的时、空联系,可能具有良好的成矿潜力;该区印支晚期花岗岩的成岩-成矿作用的强度远超传统认识,在找矿过程中需加以重视。 展开更多
关键词 SR-ND同位素 岩浆源区 成矿效应 暗色包体 湘中
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川中地区金秋气田侏罗系沙一段有利含气区预测
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作者 关旭 李建海 +4 位作者 唐青松 韦滕强 张少敏 王小娟 朱讯 《大庆石油地质与开发》 北大核心 2025年第1期131-141,共11页
针对金秋气田沙溪庙组一段(沙一段)河道砂体普遍致密化、物性差且非均质性强的问题,通过正演模拟优选多种叠前属性,运用三维透视和人工智能反演开展砂体边界、储层和含气性预测,优选致密气开发有利区。结果表明:沙一段Ⅲ、Ⅳ砂组河道最... 针对金秋气田沙溪庙组一段(沙一段)河道砂体普遍致密化、物性差且非均质性强的问题,通过正演模拟优选多种叠前属性,运用三维透视和人工智能反演开展砂体边界、储层和含气性预测,优选致密气开发有利区。结果表明:沙一段Ⅲ、Ⅳ砂组河道最发育,河道集中在西部近物源区,向东宽度明显变窄,Ⅱ砂组和Ⅴ砂组次之,Ⅰ砂组河道数量最少。沙一段储层受分流河道控制明显,Ⅲ砂组和Ⅳ砂组储层厚度普遍大于8 m,呈连片状集中分布在西部JQ8井区,或呈条带状局限分布于东部JQ5H井区,Ⅱ砂组和Ⅴ砂组储层厚度为6~8 m,分别位于西部JQ8井区河道交汇处和东部JQ5H井区分流河道内部。通过人工智能有监督的学习,预测各砂组有利含气区,Ⅲ和Ⅳ砂组含气饱和度高,气藏集中分布在JQ8、JQ5H井区河道交汇处,Ⅱ砂组气藏呈窄条状分布在JQ8和JQ5H井区河道发育区,Ⅴ砂组则局限分布在QL7和JH5井区分流河道内。Ⅲ、Ⅳ砂组河道和储层厚度大,含气饱和度高,是致密气开发重点目的层。研究成果可以为川中地区金秋气田沙一段致密气高效开发提供地质依据。 展开更多
关键词 砂体预测 地震属性 致密砂岩气藏 沙一段 金秋气田 川中地区
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Research on the Green Planning in Rural Settlements of Hui Nationality in Central Ningxia
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作者 李晓玲 《Journal of Landscape Research》 2010年第3期1-4,共4页
Targeted at the residence status in rural settlements of Hui people in central Ningxia Hui Nationality Autonomous Region, this research revealed that the construction of new countryside and the transformation of old c... Targeted at the residence status in rural settlements of Hui people in central Ningxia Hui Nationality Autonomous Region, this research revealed that the construction of new countryside and the transformation of old countryside all have to be on the basis of present topography, landform, environment, social-economic level, education, religion, customs, living habits and so on. The primary goal of this research was to find a method of ecology, low energy consumption and sustainable development to bring the green planning implementation strategies, to provide guidance for sustainable planning in the rural settlements of Hui Nationality in central Ningxia. 展开更多
关键词 The rural areas of central Ningxia Settlements of Hui Nationality Green planning Sustainable development
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