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Sedimentary Characteristics,Ages,and Environmental Significance of Gravel Deposits and Loess in Shandong,Eastern China:Regional Response to Global Change Since the Last Glacial Period
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作者 WANG Min KONG Fanbiao +6 位作者 KONG Xianglun CHEN Haitao WANG Jiawei MIAO Xiaodong JIA Guangju HAN Mei XU Shujian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期491-504,共14页
Investigation of rarely studied gravel layers found in the loess in Shandong Province,eastern China,reveals the fabric characteristics of two gravel layers(G1,G2)and the sedimentary characteristics of loess at the typ... Investigation of rarely studied gravel layers found in the loess in Shandong Province,eastern China,reveals the fabric characteristics of two gravel layers(G1,G2)and the sedimentary characteristics of loess at the typical and well-preserved Heiyu section(HY),where,to determine the paleoclimatic changes during Marine Isotope Stage 3a.Optically stimulated luminescence dates of the HY formation range from 0.26±0.02 ka to 39.00±2.00 ka.In addition,the ages of G1 and G2 were estimated using the Bayesian model to be 39.60-40.50 and 29.00-29.50 ka.G1 and G2 are mainly composed of fine and medium gravel,both of which were subangular to subrounded limestone,with gravel directions to NE and E.The average flow velocity,average depth,and flood peak flow of G1 are 1.10 m/s,0.49 m,and 37.04 m^(3)/s,respectively,calculated using the flow energy method,whereas those of G2 are 0.98 m/s,0.38 m,and 18.38 m^(3)/s,respectively.Analysis of climate proxy indices show that the sedimentary environment of the gravel and loess in HY might be a regional response to global change. 展开更多
关键词 PALEOENVIRONMENT GEOCHRONOLOGY gravel layer SEDIMENTOLOGY PLEISTOCENE shandong Province
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Analysis on the Development Model of Relic and Museum Tourism Products Based on ERP Analysis:A Case Study on Shandong Province
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作者 WANG Xia 《Journal of Landscape Research》 2024年第1期77-82,共6页
In recent years, the trend of people choosing relic and museum tourism during their vacationand leisure time is growing day by day, mainly because it touches people's feelings about historical relicsand cultural h... In recent years, the trend of people choosing relic and museum tourism during their vacationand leisure time is growing day by day, mainly because it touches people's feelings about historical relicsand cultural heritage. The development of relic and museum tourism products is not only the inheritanceof culture and the protection of cultural relics, but also the promotion of tourism consumption under thebackground of cultural tourism integration, which has promoted the development of regional economy.With the relic and museum tourism resources in Shandong Province as the research object, through theanalysis of its resources, market and products, this paper put forward three applicable modes of relic andmuseum tourism product development, including independent development, joint development, and artauthorization, and proposed specific suggestions around the three modes. 展开更多
关键词 ERP analysis Relic and museum tourism Product development shandong Province
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Characteristics of Dry and Wet Climate in Shandong Province Based on Standardized Precipitation Index
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作者 Ningxin ZHANG Fengling ZENG Fang LI 《Meteorological and Environmental Research》 2024年第3期6-15,共10页
Based on the monthly precipitation data of 116 meteorological stations in Shandong Province during 1970-2021,standardized precipitation index(SPI)was calculated,and the methods of linear fitting,mutation test and Morl... Based on the monthly precipitation data of 116 meteorological stations in Shandong Province during 1970-2021,standardized precipitation index(SPI)was calculated,and the methods of linear fitting,mutation test and Morlet wavelet analysis were used to analyze the change trend and temporal and spatial distribution characteristics of SPI index in the past 52 years.The results show that there were more normal years in Shandong Province,and the frequency reached 38.46%.There was severe drought in the 1980s and more wet years after 2003.SPI index showed an upward trend in spring,summer and winter but a weak arid trend in autumn.In addition,intense dry weather was more frequent in summer.Spatially,the climate was normal or humid in most areas of Shandong Province.The regions with more wet years were located in the central and northeast Shandong and the peninsula,while the climate was normal in the southwest and north of Shandong.The areas with more dry years were mainly located in the northwest of Shandong Province.There was mainly local and global drought in Shandong Province,and the arid area showed a decreasing trend.In the past 52 years,Shandong Province experienced quasi-4 times of alternation between dry and wet climate.The long period of 21 a was the first main period,and the climate would be still wet in Shandong Province in the future.In terms of mutation,the climate in Shandong Province became humid after 2003,and 2003 was the mutation point.After the abrupt change,the climate changed from gradually drying to wetting. 展开更多
关键词 Standardized precipitation index shandong Province Dry and wet climate characteristics Trend analysis
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Analysis of the Characteristics and Development Direction of Services Trade in Shandong Province of China
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作者 Huiqian Yu 《Proceedings of Business and Economic Studies》 2024年第1期139-144,共6页
Shandong is a significant province for foreign trade in China;however,it still faces shortcomings in the development of its service trade,as outlined below.Firstly,the scale of service trade is limited.Shandong’s ser... Shandong is a significant province for foreign trade in China;however,it still faces shortcomings in the development of its service trade,as outlined below.Firstly,the scale of service trade is limited.Shandong’s service trade volume ranked sixth in China in 2022,lagging considerably behind Shanghai,Guangdong,Beijing,Zhejiang,and Jiangsu.Secondly,the proportion of service trade in Shandong compared to the overall national services trade volume falls below the national average,with the per capita scale even lower than the national average.Thirdly,Shandong’s service trade accounts for less than 10% of the province’s foreign trade,which is 3 percentage points below the national average.The insufficient development of Shandong’s service trade is mainly attributed to the weak performance of its own service industry and the limited scale of attracting foreign services investment.Accelerating the development of producer services in Shandong,promoting the intelligent upgrading of consumer services,and continuously promoting reform and opening up in the service sector will be conducive to achieving high-quality development of services trade in Shandong. 展开更多
关键词 shandong Services trade Productive services trade
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Sustainable Intensification and Large-scale Operation of Cultivated Land Use at the Farmers’ Scale:A Case Study of Shandong Province,China
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作者 LI Li LYU Xiao +2 位作者 ZHANG Anlu NIU Shandong PENG Wenlong 《Chinese Geographical Science》 SCIE CSCD 2024年第1期149-167,共19页
Sustainable intensification of cultivated land use(SICLU) and large-scale operations(LSO) are widely acknowledged strategies for enhancing agricultural performance.However,the existing literature has faced challenges ... Sustainable intensification of cultivated land use(SICLU) and large-scale operations(LSO) are widely acknowledged strategies for enhancing agricultural performance.However,the existing literature has faced challenges in precisely defining SICLU and constructing comprehensive indicators,which has hindered the exploration of factors influencing LSO within the SICLU framework.To address this gap,we integrated self-efficacy theory into the design of an index framework for evaluating SICLU.We subsequently employed econometric models to analyze the significant factors that impact LSO.Our findings reveal that SICLU can be divided into four key dimensions:intensive management,efficient output,resource conservation,and ecological environment optimization.Furthermore,it is crucial to incorporate belief-based cognitive factors into the index system,as farmers’ understanding of fertilizer and pesticide application significantly influences their willingness to engage in LSO.Moreover,we identify grain market turnover as the most influential factor in promoting LSO,with single-factor contribution rates reaching 70.9% for cultivated land transfer willingness and 62.5% for the total planting areas.Interestingly,unlike irrigation and agricultural machinery inputs,increased labor inputs correspond to larger planting areas for farmers.This trend may be attributed to reduced labor availability because of rural labor migration,whereas the reduction in irrigation and agricultural input is contingent on innovations in production practices and the transfer of cultivated land management rights.Importantly,SICLU dynamically influences LSO,with each index related to SICLU having an optimal range that fosters LSO.These insights offer valuable guidance for policymakers,emphasizing farmers as their central focus,with the adjustment of input and output factors as a means to achieve LSO as the ultimate goal.In conclusion,we propose research avenues for further enriching the SICLU framework to ensure that it aligns with the specific characteristics of regional agricultural development. 展开更多
关键词 sustainable intensification of cultivated land use(SICLU) SELF-EFFICACY status quo bias input and output Boosted Regression Tree willingness to transfer cultivated land cultivated land planting areas shandong China
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Application of Immersive Media Technology in Ideological and Political Theory Courses Instruction at Shandong Vocational Colleges
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作者 Guoqing Liu Tingting Guo Ohamariah Samu 《Journal of Contemporary Educational Research》 2024年第5期187-193,共7页
This paper describes how virtual classrooms and out-of-classroom instruction can be used to help students in ideological and political theory courses strengthen their identities and improve the efficiency of their ass... This paper describes how virtual classrooms and out-of-classroom instruction can be used to help students in ideological and political theory courses strengthen their identities and improve the efficiency of their assignments.By using immersive media technology,the course is turned into a form of entertainment,enriched with content,and combined with methods such as digital video editing and manipulation to meet the needs of students in university ideological and political theory courses.Virtual reality technology can create realistic virtual environments created by computers,enabling students to perceive and manipulate a variety of virtual objects,interact with them,and create a sense of immersion in the virtual environment.Research has shown the potential benefits of using immersive media technologies and augmented reality in education.The potential of virtual reality in education has been increasingly emphasized and has been widely researched and applied. 展开更多
关键词 Immersive technology High school ideological and political program Virtual classroom shandong education
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A Comparative Study on the Communication of“Friendly Shandong”Official Account on Different Short Video Platforms
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作者 CHEN Fangying LI Xichao 《Journal of Landscape Research》 2023年第3期47-50,共4页
Taking“Friendly Shandong”official account as an example,the relevant data of the account on the four platforms of Tiktok,Kwai,Bilibili and Little Red Book were comparatively analyzed to study the influence of short ... Taking“Friendly Shandong”official account as an example,the relevant data of the account on the four platforms of Tiktok,Kwai,Bilibili and Little Red Book were comparatively analyzed to study the influence of short video on the communication of Shandong tourism image.The research mainly included two aspects:fan persona features and interactive effects.Through comparative study,it will provide a reference for the operation team of“Friendly Shandong”official account to spread the tourism image of Shandong with different platforms. 展开更多
关键词 Friendly shandong Short video platform COMMUNICATION Comparative study
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Optimum Application Rate of Nitrogen in Summer Peanut in Southern Shandong Area
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作者 Hongjie TANG 《Asian Agricultural Research》 2023年第3期34-36,共3页
[Objectives]To study the effect of nitrogen(N)on the growth demand of summer peanuts under a certain level of phosphorus and potassium fertilizers,and to carry out experiments on nitrogen fertilizer control of summer ... [Objectives]To study the effect of nitrogen(N)on the growth demand of summer peanuts under a certain level of phosphorus and potassium fertilizers,and to carry out experiments on nitrogen fertilizer control of summer peanuts.[Methods]Four treatments were set up in the experiment:no-nitrogen plot(N 0P_(4)K_(4)),optimized nitrogen plot(N_(7)P_(4)K_(4)),70%optimized nitrogen plot(N_(5)P_(4)K_(4)),130%optimized nitrogen plot(N 9P 4K 4),repeated 3 times,and arranged in random blocks.The area of the plot was 42 m^(2),ridges were set between the plots,and protective rows of more than 1 m were set around the experimental site.The types of fertilizers were urea,superphosphate,and imported potassium chloride,and the variety of peanuts was Linhua 5.Except for the level of fertilization,other agricultural operations were the same,and soil sampling tests,field records,and yield testing were carried out according to the requirements of the plan.[Results]On the basis of 60 kg/ha of phosphorus and potassium fertilizer application,the optimum economical fertilizer application rate and the highest application rate of pure nitrogen were about 115.20 and 131.25 kg/ha,respectively.[Conclusions]This study is expected to provide a certain basis for the high-quality and high-yield summer peanuts in southern Shandong area. 展开更多
关键词 Southern shandong area Summer peanut Nitrogen fertilizer Optimum application rate
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Spatiotemporal Characteristics of Droughts and Floods in Shandong Province,China and Their Relationship with Food Loss 被引量:1
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作者 YANG Wentong ZHANG Liyuan YANG Ziyu 《Chinese Geographical Science》 SCIE CSCD 2023年第2期304-319,共16页
Mastering the pattern of food loss caused by droughts and floods aids in planning the layout of agricultural production,determining the scale of drought and flood control projects,and reducing food loss.The Standardiz... Mastering the pattern of food loss caused by droughts and floods aids in planning the layout of agricultural production,determining the scale of drought and flood control projects,and reducing food loss.The Standardized Precipitation Evapotranspiration Index is calculated using monthly meteorological data from 1984 to 2020 in Shandong Province of China and is used to identify the province’s drought and flood characteristics.Then,food losses due to droughts and floods are estimated separately from disaster loss data.Finally,the relationship between drought/flood-related factors and food losses is quantified using methods such as the Pearson correlation coefficient and linear regression.The results show that:1)there is a trend of aridity in Shandong Province,and the drought characteristic variables are increasing yearly while flood duration and severity are decreasing.2)The food losses caused by droughts in Shandong Province are more than those caused by floods,and the area where droughts and floods occur frequently is located in Linyi City.3)The impact of precipitation on food loss due to drought/flood is significant,followed by potential evapotranspiration and temperature.4)The relationship between drought and flood conditions and food losses can be precisely quantified.The accumulated drought duration of one month led to 1.939×10^(4)t of grain loss,and an increase in cumulative flood duration of one month resulted in1.134×10^(4)t of grain loss.If the cumulative drought severity and average drought peak increased by one unit,food loss due to drought will increase by 1.562×10^(4)t and 1.511×10^(6)t,respectively.If the cumulative flood severity and average flood peak increase by one unit,food loss will increase by 8.470×103t and 1.034×10^(6)t,respectively. 展开更多
关键词 drought disaster flood disaster food loss Pearson correlation Standardized Precipitation Evapotranspiration Index shandong China
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Good Wine Needs No Bush——Exclusive Interview with Rita Kung,Investor,Board Member and CEO of Shandong Mystic Island Winery
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作者 Ada Wang 《China's Foreign Trade》 2023年第5期44-44,共1页
Rita Kung is the board member and CEO of Shandong Mystic Island Winery.From working in an international metropolis to living in a quiet village,from being a senior manager to the CEO of a winery,from having little kno... Rita Kung is the board member and CEO of Shandong Mystic Island Winery.From working in an international metropolis to living in a quiet village,from being a senior manager to the CEO of a winery,from having little knowledge of wine culture to being very familiar with the industry,Rita has always taken changes in her career in her stride.She always believes that in order to start or develop a business,once the direction is clear,we must put our whole hearts into the operation and remain patient. 展开更多
关键词 ISLAND shandong WINE
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Preliminary Research on Biological Characteristics of Scopula subpunctaria in Shandong Tea Region
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作者 Ling HAN Yingsan XIA 《Plant Diseases and Pests》 CAS 2023年第4期24-27,共4页
[Objectives]The paper was to observe the life history and living habits of Scopula subpunctaria in Shandong tea region.[Methods]The occurrence period and duration of each insect state,as well as duration of each insta... [Objectives]The paper was to observe the life history and living habits of Scopula subpunctaria in Shandong tea region.[Methods]The occurrence period and duration of each insect state,as well as duration of each instar larvae in various generations were investigated and statistically analyzed.[Results]There were 6 generations of S.subpunctaria per year in Shandong tea region.Different from southern tea region,S.subpunctaria survived the winter as pupae and larvae in tea trees in Shandong,and the duration of overwintering eggs was greatly affected by temperature.The generations of S.subpunctaria overlapped seriously.[Conclusions]The results provide a basis for the comprehensive treatment of S.subpunctaria in Shandong tea region. 展开更多
关键词 shandong tea region Scopula subpunctaria Life history Living habits
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Hospitable Shandong,Meet the Sea Along the Yellow River
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《China & The World Cultural Exchange》 2023年第9期20-21,共2页
From July 21 to 27,the Yellow River Tourism Overseas Promotion Season 2023 launched the"Shandong Overseas Promotion Week"to present"Meet the Sea along the Yellow River"Shandong Cultural Tourism Pho... From July 21 to 27,the Yellow River Tourism Overseas Promotion Season 2023 launched the"Shandong Overseas Promotion Week"to present"Meet the Sea along the Yellow River"Shandong Cultural Tourism Photo Exhibition and Shandong Cultural Tourism Promotional Video to the global public. 展开更多
关键词 shandong YELLOW EXHIBITION
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Promotion of Shandong Culture and Tourism to Open a Window for the Spanish People to Understand China
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作者 An Sheng 《China & The World Cultural Exchange》 2023年第5期18-20,共3页
On May 9,the Cultural and Tourist Promotion Activity,"Hometown of Confucius,Hospitable Shandong"as well as"Tea for Harmony:Yaji Cultural Salon"Shandong Special Activity,co-sponsored by Shandong Pro... On May 9,the Cultural and Tourist Promotion Activity,"Hometown of Confucius,Hospitable Shandong"as well as"Tea for Harmony:Yaji Cultural Salon"Shandong Special Activity,co-sponsored by Shandong Provincial Department of Culture and Tourism,Network of International Culturalink Entities and Foreign Affairs Office of Shandong Provincial People's Government,was successfully held in China Cultural Center in Madrid,Spain. 展开更多
关键词 shandong HARMONY OPEN
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Study on Influence of the COVID-19 Epidemic on Tourism Consumption Structure in Shandong Province
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作者 Dongmei ZHANG Qinglin DAI 《Agricultural Biotechnology》 2023年第6期66-70,共5页
At the end of 2019,the sudden outbreak of the COVID-19 epidemic brought great challenges to the world,and China's tourism industry suffered an unprecedented heavy blow.Exploring the impact of the epidemic on touri... At the end of 2019,the sudden outbreak of the COVID-19 epidemic brought great challenges to the world,and China's tourism industry suffered an unprecedented heavy blow.Exploring the impact of the epidemic on tourism consumption structure has become a research focus in the post-epidemic era.In this study,based on Shandong Tourism Statistics Handbook from 2018 to 2020,taking Shandong Province as an example,the changes of total tourism revenue and tourism consumption structure in Shandong Province before and after the COVID-19 epidemic were compared to predict the development of tourism in Shandong Province in the post-epidemic era and find out existing problems,and optimization paths were put forward for the development of tourism in Shandong Province in the post-epidemic era. 展开更多
关键词 COVID-19 epidemic shandong Province Tourism consumption structure Post-pandemic era
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The Impact of Internships on the Skill Acquisition Among Nursing Students in Vocational Colleges of Shandong Province
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作者 Shugang Wang Hariharan N Krishnasamy 《Journal of Contemporary Educational Research》 2023年第10期92-97,共6页
This research investigates the impact of internships on skill acquisition among nursing students in vocational colleges in Shandong Province.By employing a mixed-methods approach involving surveys and interviews,the s... This research investigates the impact of internships on skill acquisition among nursing students in vocational colleges in Shandong Province.By employing a mixed-methods approach involving surveys and interviews,the study re-veals the positive influence of internships on students’clinical competencies,professional qualities,and readiness for the workforce.Survey findings indicate heightened practical capabilities and increased confidence among students.Interviews emphasize the pivotal role of mentors in guiding skills development and professional growth.However,challenges such as resource constraints and workload imbalances during internships are also highlighted.These insights contribute to the en-hancement of nursing education and the preparation of competent nursing professionals in the region. 展开更多
关键词 INTERNSHIP Nursing students Skill acquisition Vocational colleges shandong
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Soil Quality Evaluation and Technology Research on Improving Land Capability——A Case Study on Huanghuaihai Plain in Shandong Province 被引量:2
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作者 王存龙 祝德成 +4 位作者 蒋文惠 赵西强 王红晋 喻超 伊飞 《Agricultural Science & Technology》 CAS 2014年第11期1960-1966,共7页
Based on the geochemical data obtained from the national project about the prevention and control of soil contamination, this paper explored the properties of soil chemical elements in Huanghuaihai Plain, Shandong Pro... Based on the geochemical data obtained from the national project about the prevention and control of soil contamination, this paper explored the properties of soil chemical elements in Huanghuaihai Plain, Shandong Province. The results showed that among the grade-one nutritive elements in soil, organic matter, nitrogen and phosphorus were relatively deficient while potassium was rich. Meanwhile, as the grade-two nutritive elements, calcium oxide and magnesium oxide were relatively short and sulfur’s content was abundant. About the other beneficial and trace nutri-tive elements, iron oxide, manganese, molybdenum and boron were deficient, but the content of chlorine was high, hardly lack. The main barriers to improving land productivity were soil salinization and soil heavy metal contamination. The values of soil integrated fertility index that most of the soil in the study area is middle-lower fertilized. Specifical y, the low fertility area and lower fertility area are 6 1604 and 1 244 km2 respectively, occupying about 97.43% and 1.97% of the total area. The moderate fertility soil has an area of 172 km2, occupying about 0.27% of the total area. The higher fertility soil covers an area of 128 km2, while the high fertility area of only 76 km2. This article proposed scientific fertilization, elimination of soil obsta-cle, remediation of heavy-metal-contaminated soil and other effective measures to improve land productivity according to the basic investigation results, which provides a good technological support for the planning and development of good-quality and high-benefit agriculture. 展开更多
关键词 Soil fertility soil-water-plant land productivity improvement Huanghuaihai Plain in shandong Province
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Spatial Agglomeration and Diffusion of Population Based on a Regional Density Function Approach:A Case Study of Shandong Province in China
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作者 Xiaohan Zhao Yanbin Chen 《Journal of Geographical Research》 2023年第3期61-80,共20页
Population density functions have long been used to describe the spatial structure of regional population distributions.Several studies have been conducted to examine the population distribution in Shandong Province,C... Population density functions have long been used to describe the spatial structure of regional population distributions.Several studies have been conducted to examine the population distribution in Shandong Province,China,but few have applied regional density functions to the analysis.Therefore,based on the 2000,2010,and 2020 population censuses,this study used monocentric and polycentric regional density functions to study the characteristics of population agglomeration and diffusion in Shandong.This is followed by an in-depth discussion based on population growth rate data and hot-and cold-spot analyses.The results showed that the Shandong Province population was spatially unevenly distributed.Population growth rates were higher in urban centers and counties,with more significant changes in population size in the eastern coastal areas than in the inland areas.As verified in this study,the logarithmic form of the single-center regional density function R2 was greater than 0.8,which was in line with the population spatial structure of Shandong Province.During the study period,the estimated population density of the regional center and the absolute value of the regional population density gradient both increased,indicating a clear and increasing trend of centripetal agglomeration of regional centers over the study period.Overall,the R2 value of the multicenter region density function was higher than that of the single-center region density function.The polycentric regional density function showed that the population density gradient of some centers had a downward trend,which reflected the spatial development trend of outward diffusion in these centers.Meanwhile,the variation in the estimated population density and the population density gradient exhibited differences in the central population distribution patterns at different levels. 展开更多
关键词 Regional density functions Population spatial structure shandong Province
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Petrogenesis of Mesozoic High-Mg Diorites in Western Shandong: Evidence from Chronology and Petro-geochemistry 被引量:24
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作者 Yang Chenghai Xu Wenliang +3 位作者 Yang Debin Liu Changchun Liu Xiaoming Hu Zhaochu 《Journal of China University of Geosciences》 SCIE CSCD 2005年第4期297-308,共12页
The high-Mg diorites, widely occurring in western Shandong, have important implications in the study of the relationship between the Mesozoic magmatism and the nature of the lithosphere and its thinning period in the ... The high-Mg diorites, widely occurring in western Shandong, have important implications in the study of the relationship between the Mesozoic magmatism and the nature of the lithosphere and its thinning period in the eastern North China craton (NCC). The Tietonggou and Jinling intrusions are typically representatives. LA-ICP-MS zircon U-Pb dating, major and trace element and Sr-Nd isotopic compositions of the Mesozoic intrusive rocks from western Shandong, eastern China, were analyzed. The weighted mean 106^pb/ 238^U ages from LA-ICP-MS zircon U-Pb dating results for early norite-diorite, late pyroxene-diorite from the Tietonggou intrusion and biotite-diorite from the Jinling intrusion are (131.4±4.9) Ma(n=15), (134. 5±2.3) Ma(n=13), and (132.8±4. 2) Ma(n=12), respectively, implying that they were formed in the Early Cretaceous. The weighted mean 207^pb/ 204^Pb ages for round zircons from late pyroxene-diorite in the Tietonggou intrusion is ( 2 513 ± 54) Ma( n= 8), suggesting that the basement of the North China craton should exist in the research area. The high-Mg diorites are characterized by enrichment in MgO, Na20, and light rare earth elements (LREE), and they are poor in heavy rare earth elements (HREE) and high field strength elements (HFSE), being similar to adakite. The existence of the mantle peridotite xenoliths with a high-Mg feature for these intrusive rocks implies that their primary magma should be derived from the upper mantle. However, Sr-Nd isotopic composi- tions (Is: 0.704 75--0.707 15;ENd (130 Ma) values: --3.95 to -- 13.30), depletion in HFSE, and the occurrence of Archean inherited zircons suggest that crustal materials could be involved in the derivation of the primary magma. The compositional difference between the diorites from the Tietonggou and Jinling intrusions could be attributed to those of magma sources and degrees of partial melting. The Early Cretaceous high-Mg diorites are considered to have been formed by the mixed melting of the delaminated lithosphere (lithospheric mantle + crust) and asthenosphere, based on their geochemistry, the mantlederived xenoliths, and the Early Mesozoic lithospheric evolutionary history of the eastern North China craton. 展开更多
关键词 high-Mg diorite CHRONOLOGY get chemistry MESOZOIC western shandong.
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Analysis of the Impact of Off-farm Employment of Agricultural Labor on Grain Production in Shandong Province and Henan Province 被引量:3
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作者 朱琳 刘彦随 《Agricultural Science & Technology》 CAS 2012年第7期1609-1615,共7页
[Objective] This study aimed to investigate the impact of off-farm employment of agricultural labor on grain production. [Method] Impact of off-farm employment of agricultural labor on grain production was investigate... [Objective] This study aimed to investigate the impact of off-farm employment of agricultural labor on grain production. [Method] Impact of off-farm employment of agricultural labor on grain production was investigated based on path analysis by using data from 200 counties and cities in Shandong Province and Henan Province in 2000 and 2008. [Result] Off-farm employment of agricultural labor affects grain production through agricultural land use patterns, off-farm employment of agricultural labor has negative impacts on grain production through multiple cropping index and positive impacts through the proportion of grain planting area. The positive impacts were greater in 2008. [Conclusion] Prerequisite of the positive impacts of off-farm employment on grain production is the substitution of agricultural mechanization development and agricultural technology advancement for agricultural labor. Orderly land circulation and scale land use should be promoted to avoid the lack of agricultural labor due to off-farm employment. 展开更多
关键词 Off-farm employment of agricultural labor Grain Production Path Analysis shandong Province Henan Province
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The Variation of Extreme Temperature and Precipitation in Shandong Province during 1961-2008 被引量:5
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作者 薛德强 王兴堂 《Meteorological and Environmental Research》 CAS 2010年第5期51-57,共7页
We drew on data of daily average temperature,average maximum temperature,average minimum temperature and precipitation from 78 meteorological stations during 1961-2008 of Shandong Province,analyzed the variation of ex... We drew on data of daily average temperature,average maximum temperature,average minimum temperature and precipitation from 78 meteorological stations during 1961-2008 of Shandong Province,analyzed the variation of extreme temperature and precipitation events.The results showed that although extreme cold days decreased by 0.23 d/a on average,after the average temperature steadily passed 10 ℃ in spring,it would still appear 1-2 days of frost,wheat and fruit trees would still suffer frozen injury every year in the central Shandong and the inland of Shandong Peninsula.Although the number of annual extreme hot days has an increasing trend obviously in Shandong and increased by 0.19 days a year.After 2000,aimed at the days of daily maximum temperature ≥ 35 ℃,the mean value and standard deviation of daily maximum temperature in summer decreased comparing with the normal year in West Shandong,and decreased by 1-3 days.In recent 50 years,the extreme precipitation trend increased,but not statistically significant.The number of light rain days has a decreasing trend and decreased by 0.17 days every year,in contrast,the frequency of downpour has an increasing trend. 展开更多
关键词 Extreme temperature Extreme precipitation Late frost The days of maximum temperature shandong Province China
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