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Volcanism at the Permian-Triassic Boundary in South China and Its Effects on Mass Extinction 被引量:21
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作者 Yin Hongfu, Huang Siji, Zhang Kexin, Yang Fengqing, Ding Meihua, Bi Xianmei and Zhang Suxin China University of Geosciences, Wuhan, Hubei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1989年第4期417-431,450-451,共17页
This paper discusses the clayrocks widespread at the Permian-Triassic boundary, which are mostly of volcanic origin. Volcanogenetic textures, structures and minerals such as high-temperature quartz are found in clayro... This paper discusses the clayrocks widespread at the Permian-Triassic boundary, which are mostly of volcanic origin. Volcanogenetic textures, structures and minerals such as high-temperature quartz are found in clayrocks at the Permian-Triassic boundary in many places. Thousands of microspherules have been collected from the Boundary clayrocks, many of which exhibit the typical features of the process from melting to cooling and solidification. indicating that they were formed by volcanic eruption or extraterrestrial impact. Volcanic effects on the Permian-Triassic mass extinction may be reflected in conodonts, algae and ammonoids. The Boundary clayrocks are found in many Permian-Triassic sections along the coast of Tethys. Their orighin remains to be studied. 展开更多
关键词 Volcanism at the Permian-Triassic Boundary in South china and Its effects on Mass Extinction MASS
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The causes and environmental effects of land use conversion during agricultural restructuring in Northeast China 被引量:6
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作者 刘彦随 甘红 +1 位作者 Jay GAO DENG Xusheng 《Journal of Geographical Sciences》 SCIE CSCD 2004年第4期488-494,共7页
During the last decade of the 20th century, extensive conversion inagricultural land use took place in Northeast China. The goal of this study is to ascertain itsspatial distribution and regional differentiation, dete... During the last decade of the 20th century, extensive conversion inagricultural land use took place in Northeast China. The goal of this study is to ascertain itsspatial distribution and regional differentiation, determine its causes, and analyze itsenvironmental impact. Especially we attempt to elucidate how institutional constraints havefacilitated the change at a time of agrarian restructuring when newly emerging free market washybridized with the former planned economy. Information on six categories of land use was mappedfrom interpretation of Landsat TM images recorded in 1990, 1995 and 2000. Most of land use changestook place during the first half of the decade, coinciding with abrupt and chaotic changes ingovernment directives. Farmland was changed mainly to woodland, water body and built-up areas whilewoodland and grassland were converted chiefly to farmland. Spatially, the change from farmland towoodland was restricted to the west of the study area. The change from grassland to farmland tookplace in the grazing and farming interlocked west. These chaotic and occasionally conflictingchanges were largely caused by lack of stability and consistency in agricultural land use policiespromulgated. They have exerted adverse impacts on the local environment, including land degradation,increased flooding, and modified climate regime. 展开更多
关键词 land use conversion agricultural restructuring remote sensing environmental effects northeast china
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First Surface-based Estimation of the Aerosol Indirect Effect over a Site in Southeastern China 被引量:2
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作者 Jianjun LIU Zhanqing LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第2期169-181,共13页
The deployment of the U.S. Atmospheric Radiation Measurement mobile facility in Shouxian from May to December 2008 amassed the most comprehensive set of measurements of atmospheric, surface, aerosol, and cloud variabl... The deployment of the U.S. Atmospheric Radiation Measurement mobile facility in Shouxian from May to December 2008 amassed the most comprehensive set of measurements of atmospheric, surface, aerosol, and cloud variables in China. This deployment provided a unique opportunity to investigate the aerosol-cloud interactions, which are most challenging and, to date, have not been examined to any great degree in China. The relationship between cloud droplet effective radius (CER) and aerosol index (AI) is very weak in summer because the cloud droplet growth is least affected by the competition for water vapor. Mean cloud liquid water path (LWP) and cloud optical depth (COD) significantly increase with increasing AI in fall. The sensitivities of CER and LWP to aerosol loading increases are not significantly different under different air mass conditions. There is a significant correlation between the changes in hourly mean AI and the changes in hourly mean CER, LWP, and COD. The aerosol first indirect effect (FIE) is estimated in terms of relative changes in both CER (FIEcER) and COD (FIEcoD) with changes in AI for different seasons and air masses. FIEcoD and FIEcER are similar in magnitude and close to the typical FIE value of - 0.23, and do not change much between summer and fall or between the two different air mass conditions. Similar analyses were done using spaceborne Moderate Resolution Imaging Spectroradiometer data. The satellite-derived FIE is contrary to the FIE estimated from surface retrievals and may have large uncertainties due to some inherent limitations. 展开更多
关键词 ground-based measurements aerosol indirect effect southeastern china
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Recent Progress in Studies on Land Cover Change and Its Regional Climatic Effects over China during Historical Times 被引量:10
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作者 郑景云 林珊珊 何凡能 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第4期793-802,共10页
The recent progresses on the reconstruction of historical land cover and the studies on regional climatic effects to temperature, precipitation, and the East Asian Monsoon across China were reviewed. Findings show tha... The recent progresses on the reconstruction of historical land cover and the studies on regional climatic effects to temperature, precipitation, and the East Asian Monsoon across China were reviewed. Findings show that the land cover in China has been significantly modified by human activities over the last several thousands years, mainly through cropland expansion and forest clearance. The cropland over traditional Chinese agricultural areas increased from 5.32×10^5 km^2 in the mid-17th century to 8.27×10^5 km^2 in the mid-20th century, while the forest area over the Chinese mainland had been reduced by 1.66×10^6 km^2 during the last 300 years. These changes of land cover have been detected as an important driving force of climate change by simulations of climatic effects based on various climate models (including RegCM3, RegCM2-NCC, RIEMS version1, MM5 version 2, and AGCM+SSiB) with reconstructed historical land cover data or by contrasting current land cover to potential natural vegetation. The human-induced land cover changes over China have led to the enhancement of the East Asian winter monsoon, as well as cooling in winter and warming in summer approximately since 1700. However, the simulation results on annual mean temperature, precipitation, and the East Asian summer monsoon varied from model to model, which cannot be simply attributed to certain forcing so far, but undoubtedly, using different land cover datasets in various simulations played a key role. Thus, developing different regional scales with high time resolution more accurate gridded historical land cover datasets on is needed in the future. 展开更多
关键词 climatic effects land cover change china historical climate
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Is the crop insurance program effective in China? Evidence from farmers analysis in five provinces 被引量:3
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作者 WANG Ke ZHANG Qiao +1 位作者 Shingo Kimura Suraya Akte 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第10期2109-2120,共12页
This paper aims to evaluate the effectiveness of the Chinese crop insurance program in terms of farmers' utility and welfare. A simulation model based on the power utility function was first developed to evaluate the... This paper aims to evaluate the effectiveness of the Chinese crop insurance program in terms of farmers' utility and welfare. A simulation model based on the power utility function was first developed to evaluate the effectiveness of crop insurance. Then, the Monte Carlo approach was used to generate the datasets of area, price, yield, cost, and income based on the characteristics of representative farmers, which were clustered and calibrated using the farm-level data of 574 individual farmers from five Chinese provinces. Finally, the effectiveness of Chinese crop insurance was evaluated by comparing the certainty equivalence(CE) of farmers' utility/welfare under alternative crop insurance scenarios. Government subsidy is a necessary premise for implementing the crop insurance program. The government should subsidize more than 50% of the crop insurance premium to motivate more farmers to participate in the program. The findings also show that the current crop insurance program in China has increased the farmers' welfare but still need to be improved to achieve the Pareto improvement and to make full use of the financial fund of the government. This paper is believed to not only extend academic research but also has significant implications for policymakers, especially in the context of rapid development of Chinese crop insurance with much issues such as rate, subsidy and coverage level needed to be improved. 展开更多
关键词 crop insurance effectiveness evaluation expected utility model china
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The continental shelf wave of the East China Sea and its effect on the Kuroshio
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作者 Kong Xiangde, Yin Xunf u and Li Fanhua First Institute of Oceanography, State Oceanic Administration, Qingdao 266003, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第3期367-374,共8页
The free shelf wave theory is applied to the practical case of the continental shelf in the East China Sea to analyse the effects of the shelf wave on the Kuroshio. The results indicate that the shelf wave in lower fr... The free shelf wave theory is applied to the practical case of the continental shelf in the East China Sea to analyse the effects of the shelf wave on the Kuroshio. The results indicate that the shelf wave in lower frequency travels from north to south and its phase velocity is proportional to the Kuroshio's current velocity) the maximum current velocity of the Kuroshio lies at the continental margin. The analytical solutions obtained indicate that the hydrodynamic characters of the sea region over the shelf present band structure. The horizontal motion ( x -component) caused by the shelf wave at the margin may be one of the causes for generating wavy pattern of the Kuroshio's axis . 展开更多
关键词 The continental shelf wave of the East china Sea and its effect on the Kuroshio WAVE
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Geomorphological effects of plate movement during Quaternary in China' s tropics
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作者 ZHANGWeiqiang HUANGZhenguo 《Journal of Geographical Sciences》 SCIE CSCD 2004年第2期251-256,共6页
The eastern and western fronts of plate movement in Taiwan Island and Tibetan Plateau respectively are the two major sources of tectonic force for the morphogensis during Quaternary in China's tropics. Seven examp... The eastern and western fronts of plate movement in Taiwan Island and Tibetan Plateau respectively are the two major sources of tectonic force for the morphogensis during Quaternary in China's tropics. Seven examples of geomorphological effects of plate movement are enumerated to discuss the differentiation of tectonic landforms in space and time during Quaternary. The tectonic movement tends to be more active since middle Pleistocene. Some phenomena such as the arc-shape mountain systems, volcanism and crustal deformation imply that the juncture zone of eastern and western tectonic forces is located at about 110 o E. 展开更多
关键词 plate tectonic geomorphological effect china's tropics
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The Wolf Is Coming?——Multinationals's Entry and Effect on China's Manufacturing Industry
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作者 Xie Jing Master Erasmus University of Rotterdam,the Netherland 《China's Foreign Trade》 2008年第14期30-32,共3页
Nowadays,China has become the country that introduces the largest amount of foreign capital.Up to June 2008,the accumulative total number of foreign- invested enterprises in China is over 632 thousand:the total amount... Nowadays,China has become the country that introduces the largest amount of foreign capital.Up to June 2008,the accumulative total number of foreign- invested enterprises in China is over 632 thousand:the total amount of actual use of foreign capital is over US$582 billion.There are over 400 multination- als of top 500 investing in China,30 of which set up regional headquarters。 展开更多
关键词 Pro In The Wolf Is Coming Multinationals’s Entry and effect on china’s Manufacturing Industry USS
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Traditional cultural effect on modern management in China
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作者 薛本婷 《科教文汇》 2007年第11期153-154,共2页
  1.0 Summary   The report is stated the influence of traditional cultural and ideology arouse from old-time feudality system and Confucianism in modern management in China. The features of the culture provide ma...   1.0 Summary   The report is stated the influence of traditional cultural and ideology arouse from old-time feudality system and Confucianism in modern management in China. The features of the culture provide many implications to modern managers in evaluation, motivation and recruitment.…… 展开更多
关键词 Traditional cultural effect on modern management in china
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Glacier Changes and Their Effects on Northwest China
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作者 Xu Junli Liu Shiyin Feng Tong 《Meteorological and Environmental Research》 CAS 2017年第6期15-19,26,共6页
Though being considered strategically important in matters of national defense based on its abundance of natural resources,Northwest China is one of the most ecologically vulnerable areas in the country. As one of the... Though being considered strategically important in matters of national defense based on its abundance of natural resources,Northwest China is one of the most ecologically vulnerable areas in the country. As one of the region's important water sources,glaciers have gone through major changes due to climate change. An analysis of research results over the past 60 years reveals that the glaciers have been retreating in general to some degree in large river basins in Northwest China,but the rate of retreating varied largely among different regions,ranging from 0. 01% ·a^(-1) to 0. 75% ·a^(-1). Specifically,glaciers around the Lantsang River Basin and the Altay Mountains have been retreating fastest. The retreat of glaciers has already caused an increase in runoff in mountainous areas of Northwest China. Meanwhile,increases in the frequency of glacial flash floods and in the flood discharge will further enhance the probability of glacial lake outburst floods and ensuing disasters. 展开更多
关键词 GLACIER CHANGE GLACIER RUNOFF effectS NORTHWEST china
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Implementation Effect of Farmland Protection in Urumqi-Changji Economic Zone,China 被引量:2
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作者 LI Jiang-nan 《Asian Agricultural Research》 2010年第7期30-34,38,共6页
A multi-level evaluation index system is established with farmland protection as the target layer,farmland quantity,farmland quality andfarmland sustainable development as the criterion layer.And the index layer inclu... A multi-level evaluation index system is established with farmland protection as the target layer,farmland quantity,farmland quality andfarmland sustainable development as the criterion layer.And the index layer includes the quantity change of farmland,per capita farmland area,multiple cropping index,total grain yield,unit grain yield,per capita grain security coefficient,and unit machinery dynamical input.Both expert eval-uation method and factor analysis method are used to determine the weight of index.According to the data in farmland area,grain yield and eco-nomic development in Urumqi-Changji Economic Zone in the years 1996-2007,a comprehensive evaluation model of intensive farmland use inUrumqi-Changji Economic Zone is established after data standardization.The overall implementation effect of farmland protection policy is ana-lyzed by integrating the farmland quantity,farmland quality and sustainable development.Result shows that implementation effect of farmland pro-tection shows an upward trend in general in Urumqi-Changji Economic Zone in the years 1996-2007,with a fluctuation in the years 2000-2003and a stable rising phase from 2004 till now.The maximum value is 0.779 in the year 2007;the minimum value is 0.242 in the year 1996;and themean value in the years 1996-2007 is 0.454.Farmland protection at first strictly controls the farmland quantity,then pays attention to farmlandquality,and finally focuses on the sustainable use of farmland. 展开更多
关键词 Farmland protection Implementation effect Urumqi-Changji Economic Zone china
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Relevance Theory-based Cognitive Study on the Communication Effect of “China's Stories”
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作者 Yang Xiaohong Wu Lingwei 《Contemporary Social Sciences》 2017年第6期23-32,共10页
Telling the story of China and transmitting the voice of China has become a strategy to promote the national image and cultural soft power of China. Since its implementation in 2013, China has ushered in a significant... Telling the story of China and transmitting the voice of China has become a strategy to promote the national image and cultural soft power of China. Since its implementation in 2013, China has ushered in a significant change in communication ideas and approaches. This strategy also enriches the communication genres of "China's stories" and more importantly enhances its communication effect. In this context, it is necessary to understand and study the significance of this strategic practice, assess the value realization of "China's stories" during the communication process, and thereby establish a basis for future communication of more "China's stories." Based on the factors of relevance theory, this paper analyzes the ideas of and approaches to effective communication of "China's stories" and proposes corresponding strategies. 展开更多
关键词 relevance theory china’s stories communication effect cognitive study
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China Hammers Out Effective Steps to Protect Its Wetlands
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《Bulletin of the Chinese Academy of Sciences》 2000年第4期192-192,共1页
The Chinese government will step up its efforts to stop the country’s wetlands from shrinking, said Ma Fu, Deputy Director of the State’s Forestry Administration, while announcing the newly drafted the Action Plan f... The Chinese government will step up its efforts to stop the country’s wetlands from shrinking, said Ma Fu, Deputy Director of the State’s Forestry Administration, while announcing the newly drafted the Action Plan for National Wetlands Conservation on November 8th in Beijing. 展开更多
关键词 china Hammers Out effective Steps to Protect Its Wetlands
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RELATIVE SEA LEVEL RISE AND ITS EFFECTS ON ENVIRONMENT AND RESOURCES IN CHINAS COASTAL AREAS 被引量:2
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作者 杨桂山 《Chinese Geographical Science》 SCIE CSCD 1995年第2期104-115,共12页
Due to global climate warming and natural and man-made land subsidence etc., relative sea level rise in the coastal plains of China will exceed 2-3 times over the golbal mean value during the first half part of the 21... Due to global climate warming and natural and man-made land subsidence etc., relative sea level rise in the coastal plains of China will exceed 2-3 times over the golbal mean value during the first half part of the 21st century. It will result in a series of adverse impacts on evolution of natural environment and socioeconomic development of the coastal area. This paper analyses environmental and resource effects induced by relative sea level rise in China's coastal areas on the basis of rough estimate of future relative sea level rise. These effects include inundating tidal flat and wetlands and increase in inundated risk of coastal habitable land,exacerbating storm surge. coastal erosion, flooding and salt water intrusion hazards.as well as endangering land. water. tourism and living resources and their utilization. 展开更多
关键词 china’s COASTAL areas. RELATIVE SEA LEVEL RISE environmental effect resource effect
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Family Planning and its Effects On the Lives of Women in China
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《China Population Today》 1998年第Z2期19-20,共2页
关键词 Family Planning and its effects On the Lives of Women in china
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Marked Effect in Handling Patent Disputes by China's Patent Administrative Organs
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作者 He Li 《China's Foreign Trade》 1997年第9期13-13,共1页
In handling patent disputes, China observes an operational method of mutual cooperation and coordination through two channels: judicial adjudication and administrative settlement. Over the past decade, practice has pr... In handling patent disputes, China observes an operational method of mutual cooperation and coordination through two channels: judicial adjudication and administrative settlement. Over the past decade, practice has proved that the specific way of handling patent disputes by patent administrative organs has played an important role in the prompt resolu tion of patent disputes, protecting the legitimate rights and interests of patent- 展开更多
关键词 Marked effect in Handling Patent Disputes by china’s Patent Administrative Organs
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Crust-Mantle Structure and Coupling Effects on Mineralization : An Example from Jiaodong Gold Ore Deposits Concentrating Area, China 被引量:17
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作者 YangLiqiang DengJun +2 位作者 ZhangZhongjie WangGuangjie WangJianping 《Journal of China University of Geosciences》 SCIE CSCD 2003年第1期42-51,共10页
Based on the results of two dimension velo city structure, 1∶100 000 aeromagnetic anomaly, 1∶200 000 bouguer gravity anom aly and seismic anisotropy of Jiaodong and neighboring region in Shandong, China , the info... Based on the results of two dimension velo city structure, 1∶100 000 aeromagnetic anomaly, 1∶200 000 bouguer gravity anom aly and seismic anisotropy of Jiaodong and neighboring region in Shandong, China , the information of geophysical field was divided into two parts: deep and sh allow focus fields. And then, the information of two different fields was c ombined with that of deep seated geology and ore deposit features. The syntheti c result was adopted to analyze three dimension structure, to probe into crust mantle coupling effects of mineralization and dynamics of ore formation system . 展开更多
关键词 geophysical field crust mantle structure coupling effect dynamics of mineralization Jiaodong area of china.
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Remote Sensing Assessment of Ecological Effects of Marine Ranching in the Eastern Guangdong Waters, China 被引量:1
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作者 Yanfeng Wang Jing Yu Pimao Chen 《Journal of Geoscience and Environment Protection》 2018年第12期101-113,共13页
This study aims to assess ecological effects of the construction of marine ranching in the eastern Guangdong waters. Variations in sea surface temperature (SST), chlorophyll a concentration (Chl-a), catch per unit eff... This study aims to assess ecological effects of the construction of marine ranching in the eastern Guangdong waters. Variations in sea surface temperature (SST), chlorophyll a concentration (Chl-a), catch per unit effort (CPUE), biodiversity, biomass and density of benthos were compared during the pre- (August in 2011) and post- (August in 2013) marine ranching. These were based on satellite remote sensing and survey data. Results showed that the ratio of Nitrogen (N): Phosphorus (P) was closed to 16, Chl-a increased from 7.5 - 12.3 mg·m-3 to 10.4 - 16.2 mg·m-3, and CPUE increased from 2.1 - 5.5 kg·h-1 to 5.8 - 14.5 kg·h-1. The species number of fish, crustaceans, cephalopods and shellfish increased by 25, 3, 2 and 3 respectively. Shannon-Wiener biodiversity index of fish, crustaceans, cephalopods and shellfish increased by 0.5, 0.4, 0.1 and 1.0 respectively. Both biomass and density of benthos increased also. The construction of marine ranching in the eastern Guangdong had restored the habitat to some extent, and played positive effects in the conservation and proliferation of fishery resources in local area. 展开更多
关键词 Marine RANCHING ECOLOGICAL effects Remote Sensing EASTERN GUANGDONG WATERS china
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Employment Effect of the Resource-abundant Industrial Cluster in Southwestern Region of Guangxi Zhuang Autonomous Region of China——A Case of Chongzuo City 被引量:2
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作者 MA Chang-gang ZHANG Jing-song 《Asian Agricultural Research》 2011年第1期99-103,共5页
Taking Chongzuo City of Guangxi Zhuang Autonomous Region as an example, the employment effect of the resource-abundant industrial cluster in southwestern Guangxi Province is analyzed according to the data from the Cho... Taking Chongzuo City of Guangxi Zhuang Autonomous Region as an example, the employment effect of the resource-abundant industrial cluster in southwestern Guangxi Province is analyzed according to the data from the Chongzuo Statistical Yearbook , Guangxi Statistical Yearbook from 2003 to 2008 and the data from the relevant sections of Chongzuo City, and the four employment effects of industrial cluster--the spatial expansion effect of employment chain, optimizing effect of employment structure, the multiplier effect of employment absorption and the effect of improving the quality of labors and the degree of the intensity of employment and location quotient of employment. Results show that the employment absorption of sugar industry in Chongzuo City is stable and upward slightly, and it shows strong employment effect; the sugar industry in Chongzuo is not only competitive, but also has a great share of market in employment, so it owns strong absorption of employment. The countermeasures for improving the employment level of resource-abundant and industrial cluster in southwest of Guangxi Province are put forward, including elongating industrial chain and widening employment space; strengthening various kinds of formal and informal training to improve the employment capability of laborers; laying stress on industrial structure and optimizing the employment structure; strengthening the construction of the industrial economic zone towards ASEAN(Association of Southeast Asian Nations), and fully displaying the regional advantages of the offshore border. 展开更多
关键词 Resource abundant Industrial cluster Employment effect Employment intensity Location quotient of employment china
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中国对东盟直接投资的减贫效应——基于东盟八国面板数据的实证分析
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作者 吴崇伯 李岚睿 《厦门大学学报(哲学社会科学版)》 CSSCI 北大核心 2024年第4期103-115,共13页
减贫合作是新时期中国—东盟全面战略伙伴关系行动计划的核心要务。东盟国家面临不同程度的贫困问题,亟待提升减贫韧性。基于对外直接投资视角,结合2003—2019年东盟八国面板数据,实证检验了中国对外直接投资与东盟国家贫困水平之间的... 减贫合作是新时期中国—东盟全面战略伙伴关系行动计划的核心要务。东盟国家面临不同程度的贫困问题,亟待提升减贫韧性。基于对外直接投资视角,结合2003—2019年东盟八国面板数据,实证检验了中国对外直接投资与东盟国家贫困水平之间的关系。研究发现,中国对外直接投资显著降低了东盟国家的贫困率、贫困深度和贫困强度,增强了其减贫韧性。异质性检验表明,政治互信、地理距离、营商环境、经济发展水平等因素,显著影响了减贫效应。据此,高质量共建“一带一路”下,双方应优化益贫式增长路径,改善投资环境,推进基础设施互联互通,加强数字经济等重点领域投资,以此加快东盟的减贫进程。 展开更多
关键词 东盟 贫困治理 中国对外直接投资 减贫效应
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