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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:21
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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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大型城镇集中安置区搬迁移民生计资本组合对家庭收入影响机理的实证研究 被引量:1
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作者 汪磊 张薇薇 汪霞 《贵州财经大学学报》 CSSCI 北大核心 2024年第3期81-91,共11页
易地搬迁移民已成为防止规模性返贫的重要群体。当前,搬迁移民面临着就业市场风险增大,生计资本存量减少以及家庭增收困难等现实问题,优化移民生计资本内部结构,发挥生计资本间的组合效应,提升生计资本组合对移民家庭收入的贡献作用是... 易地搬迁移民已成为防止规模性返贫的重要群体。当前,搬迁移民面临着就业市场风险增大,生计资本存量减少以及家庭增收困难等现实问题,优化移民生计资本内部结构,发挥生计资本间的组合效应,提升生计资本组合对移民家庭收入的贡献作用是解决上述问题的重要途径。学界当前与易地搬迁相关的研究多聚焦分析移民生计资本对家庭总收入的作用机制,较少基于结构功能理论视角,从实证层面探讨生计资本组合对家庭不同收入来源的影响及其相互作用机制。本文以贵州省大型城镇集中安置区移民为研究对象,首先测算移民家庭生计资本,分别采用OLS和分位数回归分析生计资本与家庭收入之间的作用机理,然后采用多元线性回归模型测算生计资本间的互补效应和替代效应,构建了移民家庭收入与生计资本组合之间的矩阵分析模型,分别应用tobit和logit回归进行实证检验,并剖析了不同维度下不同生计资本组合对不同类型收入的影响。研究结果表明:(1)移民生计资本总量有助于提升家庭收入水平。在后搬迁时代,自然资本对家庭收入的边际贡献最小,而社会资本对家庭收入呈现负向影响。(2)五大资本中的人力资本与自然资本、物质资本、社会资本以及金融资本之间存在着普适性互补效应,金融资本与社会资本间存在替代效应。(3)互补性生计资本值越大,移民家庭工资收入和财产收入越高;互补性和替代性资本量均较低的家庭主要以获得转移性收入维持生计。 展开更多
关键词 大型城镇集中安置区 互补性生计资本 替代性生计资本 家庭收入结构
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抗VEGF药物联合全视网膜光凝治疗糖尿病视网膜病变的效果和预后分析 被引量:1
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作者 汤畴旺 张采华 郑上椿 《中国卫生标准管理》 2024年第12期141-144,共4页
目的探讨抗血管内皮生长因子(vascular endothelial growth factor,VEGF)药物联合全视网膜光凝(panretinal photocoagulation,PRP)治疗糖尿病视网膜病变的效果和预后分析。方法选取三明市第二医院2020年1月—2023年1月收治的50例糖尿病... 目的探讨抗血管内皮生长因子(vascular endothelial growth factor,VEGF)药物联合全视网膜光凝(panretinal photocoagulation,PRP)治疗糖尿病视网膜病变的效果和预后分析。方法选取三明市第二医院2020年1月—2023年1月收治的50例糖尿病视网膜病变者(78眼),以随机数字表法分为2组,各25例(39眼)。对照组患者给予PRP治疗,研究组给予抗VEGF药物联合PRP治疗。比较2组术前、术后恢复指标,统计患者治疗后的不良反应,评价治疗效果。结果术后,2组最佳矫正视力(best correct vision acuity,BCVA)优于术前,视网膜新生血管(retinal neovascularization,RNV)面积、中央视网膜厚度(central retinal thickness,CRT)低于术前,且研究组BCVA高于对照组;RNV面积、CRT低于对照组,差异有统计学意义(P<0.05);研究组并发症总发生率为5.13%,低于对照组的23.08%,差异有统计学意义(P<0.05);研究组治疗总有效率为94.97%,高于对照组的79.49%,差异有统计学意义(P<0.05)。结论糖尿病视网膜病变以抗VEGF药物联合PRP治疗可改善术后BCVA,减少RNV面积、CRT,降低并发症发生率,提升治疗效果。 展开更多
关键词 抗VEGF药物 全视网膜光凝 糖尿病视网膜病变 中央视网膜新生血管面积 治疗效果 预后效果
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2024年中央一号文件的突出亮点 被引量:10
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作者 姜长云 《农村金融研究》 北大核心 2024年第2期3-13,共11页
2024年中央一号文件以习近平新时代中国特色社会主义思想为指导,为2024年乃至今后一段时期的“三农”工作进行了系统部署和具体安排,呈现了一系列突出亮点。即:凸显了贯彻中央经济工作会议精神和深化对“三农”工作的规律性认识,明确了... 2024年中央一号文件以习近平新时代中国特色社会主义思想为指导,为2024年乃至今后一段时期的“三农”工作进行了系统部署和具体安排,呈现了一系列突出亮点。即:凸显了贯彻中央经济工作会议精神和深化对“三农”工作的规律性认识,明确了学习运用“千万工程”经验引领乡村全面振兴的要求,重视运用战略思维和改革创新,统筹强化软政策引领与硬政策支撑作用,坚持守正创新,确保国家粮食安全有新招,确保不发生规模性返贫底线更明确措施更有力,强调以坚持“三个提升”为重点建设宜居宜业和美乡村。 展开更多
关键词 中央一号文件 “三农”工作 推进乡村全面振兴 “千万工程”
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回顾与启示:中央苏区图书馆事业的成功实践
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作者 张芳 冯晓霞 《图书馆》 CSSCI 2024年第7期107-112,共6页
中央苏区图书馆事业为苏区文化建设作出了重要贡献,对中国图书馆的发展意义重大。文章从组织领导、服务对象、服务体系、馆藏资源、制度建设等方面回顾总结了中央苏区图书馆建设的成功实践,指出坚持党对图书馆事业的领导、服从和服务于... 中央苏区图书馆事业为苏区文化建设作出了重要贡献,对中国图书馆的发展意义重大。文章从组织领导、服务对象、服务体系、馆藏资源、制度建设等方面回顾总结了中央苏区图书馆建设的成功实践,指出坚持党对图书馆事业的领导、服从和服务于党的中心工作、树立“读者至上”的服务理念、传承弘扬苏区精神等,对做好新时代图书馆工作具有重要的启示意义。 展开更多
关键词 中央苏区 图书馆事业 组织领导 服务体系 制度建设
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城-景环游:滨江环湖城市中心区的形态优化研究
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作者 史北祥 张芷晗 +2 位作者 娄莺 崔澳 陈旭阳 《中国园林》 CSCD 北大核心 2024年第6期49-55,共7页
滨江环湖城市中心区因其自然形态与城市形态相互融合,具有湖面水体开阔、观景点位自由、界面环形观览、视廊通透绵长的观赏特点。作为滨水中心区的典型类型,如何依托其滨江环湖的双重特点进行设计优化是当前研究的重点。聚焦滨江环湖城... 滨江环湖城市中心区因其自然形态与城市形态相互融合,具有湖面水体开阔、观景点位自由、界面环形观览、视廊通透绵长的观赏特点。作为滨水中心区的典型类型,如何依托其滨江环湖的双重特点进行设计优化是当前研究的重点。聚焦滨江环湖城市中心区,基于国内外相关研究对其景观要素进行梳理并总结出4类特征,即前景开阔、动态观览、环形画卷、视野通透。进而结合其景观特征分别从点景、叠景、透景3个维度进行标志高层、观赏界面、景观视廊的设计优化。以重庆市万州中心区作为实证案例,对滨水界面进行设计优化,依托功能和类型合理布局标志建筑,结合自然要素打造城市超级视廊,以期为滨江环湖城市中心区形态优化提供设计方法及策略参考,提升城市空间品质。 展开更多
关键词 风景园林 形态优化 视觉景观 滨江环湖中心区 观景特征
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川中龙女寺地区中二叠统茅口组储层特征及其主控因素
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作者 彭军 刘芳兰 +4 位作者 张连进 郑斌嵩 唐松 李顺 梁新玉 《石油与天然气地质》 EI CAS CSCD 北大核心 2024年第5期1337-1354,共18页
近年来,川中龙女寺地区JT1井和MX145井等多口钻井在中二叠统茅口组获得高产工业气流,展现出茅口组良好的勘探开发潜力,但由于储层特征及其发育主控因素不清楚,严重制约了龙女寺地区茅口组进一步的油气勘探。以川中龙女寺地区茅口组储层... 近年来,川中龙女寺地区JT1井和MX145井等多口钻井在中二叠统茅口组获得高产工业气流,展现出茅口组良好的勘探开发潜力,但由于储层特征及其发育主控因素不清楚,严重制约了龙女寺地区茅口组进一步的油气勘探。以川中龙女寺地区茅口组储层为对象,开展储层岩性、物性和孔喉结构等地质特征及地球化学特征研究,提出了川中龙女寺地区中二叠统茅口组优质储层主控因素。研究结果表明:(1)龙女寺地区茅口组储层岩性为白云岩及灰岩2类,晶粒白云岩、角砾白云岩和颗粒灰岩为主要储层岩石类型。白云岩储层可划分为3大类、6个亚类,灰岩储层可划分为4大类、5个亚类。(2)晶间孔、非选择性溶孔和溶洞为茅口组储层主要储集空间类型,裂缝-孔洞型储层的构造-溶蚀缝、洞体系储集空间大,分布广泛且连通性好,为有利储层。(3)茅口组储层具有“沉积作用-白云石化作用构建骨架,岩溶作用-构造作用叠加改造”的形成与发育模式。沉积作用、白云石化作用和构造作用是优质储层的主要控制因素,角砾白云岩为优质储集岩。 展开更多
关键词 主控因素 演化模式 储层特征 茅口组 中二叠统 龙女寺地区 四川盆地中部
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中央苏区农业科技的研究与推广
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作者 庞振宇 《农业考古》 北大核心 2024年第1期54-62,共9页
发展农业生产不仅需要开展土地革命来激发苏区群众的积极性,还需要以农业科技的研究与推广来提高农业生产力水平。在中央苏区,中国共产党和苏维埃政府创办农事试验场、农业学校和农产品展览所,研究农业科学技术,在选育优良品种、改良土... 发展农业生产不仅需要开展土地革命来激发苏区群众的积极性,还需要以农业科技的研究与推广来提高农业生产力水平。在中央苏区,中国共产党和苏维埃政府创办农事试验场、农业学校和农产品展览所,研究农业科学技术,在选育优良品种、改良土壤、防治病虫害、兴修水利、改良农具、植树造林等方面积极推广新技术和新经验,取得了很好的成效。农业科技的研究与推广,在解决中央苏区粮食安全等方面发挥了重要作用,这是中国共产党领导农业科技事业的开端。 展开更多
关键词 苏区 农业科技 研究机构 成效
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